Glossary of Terms

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Abscess

An enclosed collection of pus in tissues, organs, or confined spaces in the body. An abscess is a sign of infection and is usually swollen and inflamed.


Achalasia

Achalasia is a rare disorder that makes it difficult for food and liquid to pass into your stomach. Achalasia occurs when the food tube (esophagus) loses the ability to squeeze food down, and the muscular valve between the esophagus and stomach doesn't fully relax.


Achlorhydria

A lack of hydrochloric acid in the digestive juices in the stomach. Hydrochloric acid helps digest food.


Adenocarcinoma

Cancer that begins in glandular (secretory) cells. Glandular cells are found in tissue that lines certain internal organs and makes and releases substances in the body, such as mucus, digestive juices, or other fluids. Most cancers of the breast, pancreas, lung, prostate, and colon are adenocarcinomas.


Adventitia

The outermost connective tissue covering of any organ, vessel, or other structure not covered by a serosa; instead, the covering is properly derived from without (i.e., from the surrounding connective tissue) and does not form an integral part of such organ or structure.


Aflatoxins

A harmful substance made by certain types of mold (Aspergillus flavus and Aspergillus parasiticus) that is often found on poorly stored grains and nuts. Consumption of foods contaminated with aflatoxin is a risk factor for primary liver cancer.


Agnogenic

Refers to a disease or condition of unknown cause or origin. Synonym: idiopathic.


Algorithm

A set of rules that solve a problem in a finite number of steps.


Amitotic

Relating to or marked by amitosis -- an unusual form of nuclear division, in which the nucleus simply constricts, rather like a cell without chromosome condensation or spindle formation. Partitioning of daughter chromosomes is haphazard.


Amoeboid

Resembling an amoeba specifically in moving or changing in shape by means of protoplasmic flow.


Ampulla

A sac-like enlargement of a canal or duct.


Amylase

An enzyme that helps the body digest starches.


Anal Verge

The external or (lower) distal boundary of the anal canal. It is where the anal tube turns outward to blend with the perianal skin, junction between the skin of the anal canal and the perianal skin.


Anaplasia

Lack of differentiated features in a cancer cell, characterized by cellular pleomorphism (variation in size and shape of cells and their nuclei), enlarged and hyperchromatic nuclei, prominant nucleoli, atypical mitoses, and bizarre cells, including giant cells.


Anastomosis

A procedure to connect healthy sections of tubular structures in the body after the diseased portion has been surgically removed.


Anemia

A condition in which the number of red blood cells is below normal.


Aneuploid

Having a chromosome number that is not an exact multiple of the haploid number.


Angiosarcoma

A type of cancer that begins in the cells that line blood vessels or lymph vessels. Cancer that begins in blood vessels is called hemangiosarcoma. Cancer that begins in lymph vessels is called lymphangiosarcoma.

Angiosarcomas are uncommon malignant neoplasms characterized by rapidly proliferating, extensively infiltrating anaplastic cells derived from blood vessels and lining irregular blood-filled spaces. Specialists apply the term angiosarcoma to a wide range of malignant endothelial vascular neoplasms that affect a variety of sites. Angiosarcomas are aggressive and tend to recur locally, spread widely, and have a high rate of lymph node and systemic metastases.


Anomaly

A marked deviation from normal standard. In anatomic terms, an incorrectly formed or placed organ. A congenital anomaly is one that is present at birth, such as an improperly developed heart value.


Anorexia

An abnormal loss of the appetite for food. Anorexia can be caused by cancer, AIDS, a mental disorder or other diseases.

Anorexia nervous is the eating disorder that is marked by an intense fear of gaining weight, a refusal to maintain a health weight and a distorted body image. People with anorexia nervosa have an abnormal loss of appetite for food, try to avoid eating, and eat as little as possible.


Antibody

A protein made by plasma cells (a type of white blood cell) in response to an antigen (a substance that causes the body to make a specific immune response). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen. An antibody is a type of immunoglobulin.


Antigen

Any substance that causes the body to make an immune response against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body. Body tissues and cells, including cancer cells, also have antigens on them that can cause an immune response. These antigens can also be used as markers in laboratory tests to identify those tissues or cells.


Antrectomy

Removal of the walls of an antrum, such as removing the pyloric antrum of the stomach.


Antrum

A general term for cavity or chamber which may have specific meaning in reference certain organs or sites in the body. The antrum of the stomach (gastric antrum) is a portion before the outlet which is lined by mucosa which does not produce acid. The paranasal sinuses can be referred to as the frontal antrum, ethmoid antrum, and maxillary antrum.


Aorta

The largest artery in the body, the aorta arises from the left ventricle of the heart, goes up (ascends) a little way, bends over (arches), then goes down (descends) through the chest and through the abdomen to where ends by dividing into two arteries called the common iliac arteries that go to the legs.

Anatomically, the aorta is traditionally divided into the ascending aorta, the aortic arch, and the descending aorta. The descending aorta is, in turn, subdivided into the thoracic aorta (that descends within the chest) and the abdominal aorta (that descends within the belly).

The aorta gives off branches that go to the head and neck, the arms, the major organs in the chest and abdomen, and the legs. It serves to supply them all with oxygenated blood. The aorta is the central conduit from the heart to the body.


Aplasia

Lacking in cell production, as in aplastic anaemia (anemia).


Ascites

Abnormal buildup of fluid in the abdomen that may cause swelling. In late-stage cancer, tumor cells may be found in the fluid in the abdomen. Ascites also occurs in patients with liver disease.


Atelectasis

Failure of the lung to expand (inflate) completely. This may be caused by a blocked airway, a tumor, general anesthesia, pneumonia or other lung infections, lung disease, or long-term bedrest with shallow breathing. Sometimes called a collapsed lung.


Atrophy

A decrease in muscle bulk due to a lack of exercise, as when a limb is in a cast for a prolonged period. Stimulation of nerves with a mild electric current can keep muscular tissue viable until full activity can return. In severe cases, the muscle fibers are actually lost and replaced with connective tissue.


Atypia

State of being not typical or normal. In medicine, atypia is an abnormality in cells in tissue.


Axon

A nerve fiber in the peripheral nervous system that conducts impulses away from the cell body.

Axons are covered by a myelin sheath and neurilemma, which is a membranous sheath that covers the axon directly or covers the myelin sheath when it is present. The myelin sheath increases the speed of the nerve impulse conduction and insulates and maintains the axon. The neurilemma assists in the regeneration of injured axons.

Axon endings are the terminal portions of the axons.
Axon terminals are the endings of the axons.


B

Bacteria

A large group of single-cell microorganisms. Some cause infections and disease in animals and humans. The singular of bacteria is bacterium.


Barium enema

A procedure in which a liquid that contains barium sulfate is put through the anus into the rectum and colon. Barium sulfate is a silver-white metallic compound that helps show pictures of the colon, rectum, and anus on an x-ray.


Barrett esophagus

A condition in which the cells lining the lower part of the esophagus have changed or been replaced with abnormal cells that could lead to cancer of the esophagus. The backing up of stomach contents (reflux) may irritate the esophagus and, over time, cause Barrett esophagus.


Basal Cell Carcinoma

Cancer that begins in the lower part of the epidermis (the outer layer of the skin). It may appear as a small white or flesh-colored bump that grows slowly and may bleed. Basal cell carcinomas are usually found on areas of the body exposed to the sun. Basal cell carcinomas rarely metastasize (spread) to other parts of the body. They are the most common form of skin cancer.


Basement membrane

A microscopic anatomic structure in most organs that forms the deep boundary of the mucosal surface. Tumor invasion or penetration through the basement membrane indicates that the tumor is no longer in situ and has become invasive or localized.


Basophil

A type of immune cell that has granules (small particles) with enzymes that are released during allergic reactions and asthma. A basophil is a type of white blood cell and a type of granulocyte.


Benzene

A chemical that is used widely by the chemical industry, and is also found in tobacco smoke, vehicle emissions, and gasoline fumes. Exposure to benzene may increase the risk of developing leukemia.


B-cells

A type of white blood cell that makes antibodies. B cells are part of the immune system and develop from stem cells in the bone marrow. Also called B lymphocyte.


Biopsy

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include are incisional biopsy and excisional biopsy.


Billroth operation I (Billroth I anastomosis)

Excision of the pylorus with end-to-end anastomosis of stomach and duodenum.


Billroth operation II (Billroth II anastomosis)

Resection of the pylorus with the greater part of the lesser curvature of the stomach, closure of the cut ends of the duodenum and stomach, followed by a gastrojejunostomy.


Blood cell count with Differential

A measure of the number of red blood cells, white blood cells, and platelets in the blood, including the different types of white blood cells (neutrophils, lymphocytes, monocytes, basophils, and eosinophils). The amount of hemoglobin (substance in the blood that carries oxygen) and the hematocrit (the amount of whole blood that is made up of red blood cells) are also measured. A blood cell count with differential is used to help diagnose and monitor many different conditions, including anemia and infection.


Bloom Syndrome

A rare, inherited disorder marked by height that is shorter than average, a narrow face with redness and a rash, a high-pitched voice, and fertility problems. Patients with this disorder have an increased risk of cancer, especially leukemia and osteosarcoma (bone cancer). Bloom syndrome is caused by changes in a protein that normally helps cells make copies of the DNA. Changes in this protein cause many breaks, rearrangements, and other mutations in the DNA. It is a type of autosomal recessive genetic disease. Synonym: Bloom-Torre-Machacek syndrome


BPH (Benign Prostatic Hyperplasia)

A benign (not cancer) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine.


BRCA1

BRCA1 or "Breast Cancer 1," is a genetic mutation that is present in about two-thirds of heritable breast cancers and a smaller number of heritable ovarian cancers. Only about 5% of the female breast cancer in the world is attributable to having the BRCA1 mutation.

This is a gene on chromosome 17 that normally helps to suppress cell growth. A person who inherits certain mutations (changes) in a BRCA1 gene has a higher risk of getting breast, ovarian, prostate, and other types of cancer.


BRCA2

BRCA2 or "Breast Cancer 2," is a genetic mutation that is present in both male and female heritable breast cancer, heritable ovarian cancer, and heritable prostate cancer. Less than 5% of cancers of the male and female breast, ovary, and prostate are attributable to the BRCA2 mutation.

This is a gene on chromosome 13 that normally helps to suppress cell growth. A person who inherits certain mutations (changes) in a BRCA2 gene has a higher risk of getting breast, ovarian, prostate, and other types of cancer.


Brenner tumor

Brenner tumors are comprised of solid to partly cystic epithelial nests surrounded by stroma composed of bundles of tightly packed spindle-shaped cells. The epithelial cells are polygonal and of squamoid type, with pale, eosinophilic cytoplasm and oval nuclei with distinct nucleoli and longitudinal grooving, which is commonly described as "coffee-bean" in appearance.


Burkitt's Lymphoma

An aggressive (fast-growing) type of B-cell non-Hodgkin lymphoma that occurs most often in children and young adults. The disease may affect the jaw, central nervous system, bowel, kidneys, ovaries, or other organs. There are three main types of Burkitt lymphoma (sporadic, endemic, and immunodeficiency related). Sporadic Burkitt lymphoma occurs throughout the world, and endemic Burkitt lymphoma occurs in Africa. Immunodeficiency-related Burkitt lymphoma is most often seen in AIDS patients. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Bypass

A surgical procedure in which the doctor creates a new pathway for the flow of body fluids.


C

CA 125 (Cancer Antigen 125)

A CA-125 test measures the amount of the cancer antigen 125 (CA-125) in a person’s blood. CA-125 is a protein that is a biomarker or tumor marker. It is found in greater concentration in cancer cells, particularly ovarian cancer cells.

Cancer types that can cause higher than normal levels of CA-125 include:
Ovarian cancer
Endometrial cancer Fallopian tube cancer
Pancreatic cancer
Stomach cancer
Esophageal cancer
Colon cancer
Liver cancer
Breast cancer
Lung cancer
Cancers that have spread to the peritoneum (the abdomen's lining)

The CA-125 test helps doctors:
Monitor ovarian cancer and other cancers to determine if they are responding to treatment Monitor patients with ovarian and other cancers post-treatment to check for cancer recurrence To an extent, screen for ovarian cancer in women who are at high risk for developing the disease


Cachexia

Loss of body weight and muscle mass, and weakness that may occur in patients with cancer, AIDS or other chronic disease.

Symptoms include weight loss, fatigue, weakness and significant loss of appetite in individuals who are not trying to lose weight.


Calcium

A mineral needed for healthy teeth, bones, and other body tissues. It is the most common mineral in the body. A deposit of calcium in body tissues, such as breast tissue, may be a sign of disease.


Cancer

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems.

There are several main types of cancer.

  • Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs.
  • Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.
  • Leukemia is a cancer that starts in blood-forming tissue, such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood.
  • Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system.
  • Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

Cancer Control

Actions taken to reduce the frequency and impact of cancer; any effort to provide information and procedures to help reduce the financial and medical burden of cancer in a population.

Cancer Control programs are specific efforts to reduce the amount or severity of a particular type of cancer.

Cancer Control also uses proven prevention, early detection, diagnosis, treatment, and continuing care intervention strategies to reduce cancer incidence, morbidity, and mortality in defined populations.


Cancer Prevention

Cancer prevention research involves the development and evaluation of strategies for reducing cancer incidence. Such strategies could be aimed at preventing the initiation of the neoplastic process or at avoiding the progression to malignancy of already initiated cells. These efforts, which may be multidisciplinary and multifactorial, can involve a broad range of studies at the molecular, cellular, organismal and population levels.


Carbohydrate

A sugar molecule. Carbohydrates can be small and simple (for example, glucose) or they can be large and complex (for example, polysaccharides such as starch, chitin or cellulose).


Carcinoid tumor

A slow-growing type of tumor usually found in the gastrointestinal system (most often in the small intestine and rectum), and sometimes in the lungs or other sites. Carcinoid tumors may spread to the liver or other sites in the body, and they may secrete substances such as serotonin or prostaglandins, causing carcinoid syndrome.


Carcinogenesis

The process by which normal cells are transformed into cancer cells.


Carcinogen

Any substance that causes cancer.


Carcinoma

Cancer that begins in the skin or in tissues that line or cover internal organs.


Casefinding

The systematic process of identifying all cases of a disease eligible to be included in the registry database for a defined population, such as patients of a hospital or residents of a state.

There are several types of casefinding:

  1. Active casefinding is performed by registry personnel who screen the source documents themselves.
  2. Passive casefinding is performed by other healthcare professionals whom the registry relies on to notify the registrar of potentially reportable cases. Also known as self-reporting.
  3. Combination casefinding is the use of active review by the registrar for critical casefinding sources and passive review of other sources as provided by reliable participants in other departments.

Casefinding Cycle

The systematic process of identifying all cases of a disease eligible to be included in the registry database for a defined population, such as patients of a hospital or residents of a state.


Catecholamine

A type of neurohormone (a chemical that is made by nerve cells and used to send signals to other cells). Catecholamines are important in stress responses. High levels cause high blood pressure which can lead to headaches, sweating, pounding of the heart, pain in the chest, and anxiety.

Examples of catecholamines include: dopamine, epinephrine (adrenaline), and norepinephrine (noradrenaline).


Cauterize

To destroy tissue using a hot or cold instrument, an electrical current, or a chemical that burns or dissolves the tissue. This process may be used to kill certain types of small tumors or to seal off blood vessels to stop bleeding.


CEA (Carcino-Embryonic Antigen)

A substance that may be found in the blood of people who have colon cancer, other types of cancer or diseases, or who smoke tobacco. Carcinoembryonic antigen levels may help keep track of how well cancer treatments are working or if cancer has come back. It is a type of tumor marker.


Celiac Disease

A digestive disease that is caused by an immune response to a protein called gluten, which is found in wheat, rye, barley, and oats. Celiac disease damages the lining of the small intestine and interferes with the absorption of nutrients from food. A person with celiac disease may become malnourished no matter how much food is consumed.


Centriole

A cylinder-shaped organelle composed of microtubules and found in the nucleus of a cell. During nuclear division it forms the spindle, which ensures that the duplicated chromosomes are equally divided between the daughter cells.


Cephalic

Of or relating to the head.


Chediak-Higashi Syndrome

A generalized cellular disorder which affects all granule-containing cells resulting in recurrent infections and ocular, neurological, and skin manifestations.


Chemotherapy

Chemotherapy is the treatment of cancer with drugs that can destroy cancer cells. These drugs often are called "anticancer" drugs. Anticancer drugs destroy cancer cells by stopping them from growing or multiplying. Healthy cells can also be harmed, especially those that divide quickly. Harm to healthy cells is what causes side effects. These cells usually repair themselves after chemotherapy.


Cholangiocarcinoma

A rare type of cancer that begins in cells that line the bile ducts. A bile duct is a tube that carries fluid called bile from the liver and the gallbladder to the small intestine. Cholangiocarcinoma may be found in the bile ducts inside the liver (intrahepatic) or outside the liver (extrahepatic). Cancer that forms in the area where the right and left bile ducts meet outside the liver is called Klatskin tumor. It is the most common type of cholangiocarcinoma.


Cholecystokinin

A hormone secreted especially by the duodenal mucosa that regulates the emptying of the gallbladder and secretion of enzymes by the pancreas and that has been found in the brain.


Choriocarcinoma

A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta). Almost all choriocarcinomas form in the uterus after fertilization of an egg by a sperm, but a small number form in a testis or an ovary. Choriocarcinomas spread through the blood to other organs, especially the lungs.

A type of gestational trophoblastic disease.


Chorion (adj. chorionic)

The highly vascular outer embryonic membrane of reptiles, birds, and mammals that in placental mammals is associated with the allantois in the formation of the placenta.


Chromatin

A complex of nucleic acid and basic proteins (as histone) in eukaryotic cells that is usually dispersed in the interphase nucleus and condensed into chromosomes in mitosis and meiosis.


Chromosome

A part of the cell that carries genes. Genes give instructions that tell the cell what to do. The cell has 46 chromosomes, 22 pairs of chromosomes plus two sex chromosomes. Females have two "X" chromosomes. Males have one "X" and one "Y" chromosome.


Chronic Myelogenous Leukemia (CML)

A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Chyme

The semifluid mass of partly digested food expelled by the stomach into the duodenum and moves through the intestines during digestion.


Cilium (pl. cilia)

A minute, short hairlike process often forming part of a fringe; especially : one on a cell that is capable of lashing movement and serves especially in free unicellular organisms to produce locomotion or in higher forms a current of fluid.


Cirrohsis

A type of chronic, progressive liver disease in which liver cells are replaced by scar (fibrous) tissue and nodules. The scar tissue and nodules lead to loss of liver function.

Cirrhosis is commonly caused by chronic alcoholism, hepatitis B, hepatitis C and fatty liver disease. There are other causes, some of which are idiopathic (unknown cause).


Classification Scheme

A logical system for the arrangement of knowledge. A fully developed classification scheme specifies categories of knowledge and provides the means to relate the categories to each other and to specify in the classification number all or the most important of the aspects and facets of a subject.


Colposcopy

A lighted magnifying instrument used to check the cervix, vagina, and vulva for signs of disease.

The procedure is a colposcopy. During colposcopy, an instrument called a speculum is inserted into the vagina to widen it so that the cervix can be seen more easily. A vinegar solution may be used to make abnormal tissue easier to see with the colposcope. Tissue samples may be taken using a spoon-shaped instrument called a curette and checked under a microscope for signs of disease. Colposcopy may be used to check for cancers of the cervix, vagina, and vulva, and changes that may lead to cancer.


Computerized Axial Tomography (CT)

A procedure that uses a computer linked to an x-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create 3-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. A CT scan may be used to help diagnose disease, plan treatment, or find out how well treatment is working.


Confidentiality

The concept of maintaining the privacy of personal information obtained in the process of work.


Conization

A procedure in which a cone-shaped piece of abnormal tissue is removed from the cervix. A scalpel, a laser knife, or a thin wire loop heated by an electric current may be used to remove the tissue. The tissue is then checked under a microscope for signs of disease. Cone biopsy may be used to check for cervical cancer or to treat certain cervical conditions. Types of cone biopsy are LEEP (loop electrosurgical excision procedure) and cold knife conization (cold knife cone biopsy).


Connective Tissue

The supporting or framework tissue of the body, formed of fibrous and ground substance with more or less numerous cells of various kinds; it is derived from the mesenchyme, and this in turn from the mesoderm; the varieties of connective tissue are: areolar or loose; adipose; dense, regular or irregular, white fibrous; elastic; mucous; and lymphoid tissue; cartilage; and bone; the blood and lymph may be regarded as connective tissues the ground substance of which is a liquid.


Core Biopsy

Similar to needle biopsy, but a larger needle is used because actual tissue is removed, rather than a tiny sampling of cells. A sample of the tumor is removed, but not the whole tumor. The types of core biopsies include ultrasound-guided core biopsy and stereotactic biopsy.


Corpus Callosum

A band-like structure deep in the brain that contains fibers which connect the two halves of the cerebral hemispheres.


Corpus luteum

The zona granulosa and theca cells remaining in the ovary after ovulation and some surrounding capillaries and connective tissue evolve into the corpus luteum.


Cortex

The external or outer surface layer of an organ, as distinguished from the core, or medulla, of the organ. In some organs, such as the adrenal glands, the cortex has a different function than the medulla.


Cranium

The bones that form the head. The cranium is made up of cranial bones (bones that surround and protect the brain) and facial bones (bones that form the eye sockets, nose, cheeks, jaw, and other parts of the face). An opening at the base of the cranium is where the spinal cord connects to the brain.

Part of the axial skeleton, which is made up of 80 bones.

The cranium contains the following bones: frontal, occipital, sphenoid, ethmoid, 2 temporal, and 2 parietal bones. They are joined together by suturae and are immovable.


Crohn's disease

A condition in which the gastrointestinal tract is inflamed over a long period of time. Regional enteritis usually affects the small intestine and colon. Symptoms include fever, diarrhea, stomach cramps, vomiting, and weight loss. Regional enteritis increases the risk of colorectal cancer and small intestine cancer. It is a type of inflammatory bowel disease (IBD).


Cryptorchidism

A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, into the scrotum. Cryptorchidism may increase the risk for development of testicular cancer. Also called undescended testicles.


Cryosurgery

A procedure in which an extremely cold liquid or an instrument called a cryoprobe is used to freeze and destroy abnormal tissue. A cryoprobe is cooled with substances such as liquid nitrogen, liquid nitrous oxide, or compressed argon gas. Cryosurgery may be used to treat certain types of cancer and some conditions that may become cancer.


Culdoscopy

The introduction of a viewing tube through the end of the vagina into the cul-de-sac. The cul-de-sac is also called the rectouterine pouch, an extension of the peritoneal cavity between the rectum and back wall of the uterus.


Cutaneous

Pertaining to the skin, dermal, dermic.


CXR

An x-ray of the structures inside the chest. An x-ray is a type of high-energy radiation that can go through the body and onto film, making pictures of areas inside the chest, which can be used to diagnose disease.


Cystic

Relating to a cyst -- any closed cavity or sac that is lined by epithelium often contains liquid or semi-solid material.


Cytogenetics

The branch of genetics that studies the structure of DNA within the cell nucleus. This DNA is condensed during cell division and forms chromosomes. Cytogenetic studies focus on the number and morphology of chromosomes using chromosome banding techniques, or fluorescently labeled probes. Cytogenetics may be part of the initial diagnostic workup for multiple myeloma.


Cytology

The microscopic review of cells in body fluids obtained from aspirations, washings, scrapings, and smears; usually a function of the pathology department. The cytology report is the documentation of the microscopic examination of cells in body fluids and their diagnosis.


Cytoplasm

The fluid inside a cell but outside the cell's nucleus. Most chemical reactions in a cell take place in the cytoplasm.


Cytotoxic Agent

A substance that kills cells, including cancer cells. These agents may stop cancer cells from dividing and growing and may cause tumors to shrink in size.


D

Data Set

A list of data elements that must be collected to meet the minimal needs of a group's goals, often with an additional list of elements that are recommended for the most effective operation.

An optional data set is the nonrequired items that enhance registry reporting and analysis; also called supplemental data set.

A required data set is the minimum set of information mandated by an organization.


Death Clearance

The process of linking death certificates from a state's vital statistics office with registry records to obtain death data for previously registered cancer cases.


Dendrite

Any of the usually branching protoplasmic processes that conduct impulses toward the body of a nerve cell.


De novo

In cancer, the first occurrence of cancer in the body.


Diapedesis

Passage of blood cells (especially white blood cells) through intact capillary walls and into the surrounding tissue.


Diaphragm muscle

Muscle of respiration. It originates in the xiphoid process, costal cartilages and lumbar vertebrae and inserts into the central tendon. Its main function is increasing the vertical diameter of the thorax.

Other muscles of respiration are: External intercostals, Internal intercostals, and Quadratus lumborum.


Diarrhea

Frequent, loose, and watery bowel movements. Common causes include gastrointestinal infections, irritable bowel syndrome, medicines, and malabsorption.


Diethylstilbestrol (DES)

A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. Diethylstilbestrol may increase the risk of uterine, ovarian, or breast cancer in women who took it. It also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to diethylstilbestrol before birth.


Differentiation

Describes how much or how little a tumor resembles the normal tissue from which it arose; also called grade.

Differentiation is often categorized as the following:

  1. Well differentiated-closing resembling normal cells.
  2. Moderately differentiated.
  3. Poorly differentiated.
  4. Undifferentiated-having no resemblance to normal cells. Also known as anaplastic.

Diploid

Individual or cell having two complete sets of chromosomes.


Disease Index

A computerized listing of patients seen in a hospital (inpatient and outpatient) organized by discharge diagnosis code. For example: unspecified hypertension is coded 401.9 (in ICD-9, but is I10 in ICD-10) and malignant neoplasm of the central portion of the female breast is coded 174.1 (in ICD-9, but is C50.1 in ICD-10).


Disease Registry

An organized system for the collection, storage, analysis, and interpretation of data on persons with the particular disease of concern.

Distal

Refers to positions farther away from the origin, a reference point, source or attachment.

Diverticulum

A small sac-like structure that sometimes forms in the walls of the intestines, diverticula can trap particles of food (especially small seeds and undigested grains) and become very inflammed and painful (this condition is called diverticulitis).

DNA

The molecular basis of heredity; encodes the genetic information responsible for the development and function of an organism and allows for transmission of that genetic information from one generation to the next. The DNA molecule is structured as a double-stranded helix held together by weak hydrogen bonds between purine-pyrimidine nucleotide base pairs: adenine (A) paired with thymine (T), and guanine (G) paired with cytosine (C).

Dorsal

Pertaining to, or situated near, the back, or dorsum, of an animal or of one of its parts.

Down Syndrome

A disorder caused by the presence of an extra chromosome 21 and characterized by mental retardation and distinguishing physical features.

Dysphagia

Difficulty in swallowing.

Dysplasia

Cells that look abnormal under a microscope but are not cancer.

E

Echography

Echography (ultrasound, ultrasonography or sonography) is a diagnostic test using high frequency sound waves that is utilized by many medical specialties.


Electrolyte

A substance that, when dissolved in a suitable solvent or when fused, becomes an ionic conductors. These are mainly ions such as sodium potassium, ammonium chloride, bicarbonate, phosphate, and sulfate. Levels vary with diet and other factors.


Embolism

A block in an artery caused by blood clots or other substances, such as fat globules, infected tissue, or cancer cells.


Embryo

Early stage in the development of a plant or an animal. In vertebrate animals (have a backbone or spinal column), this stage lasts from shortly after fertilization until all major body parts appear. In particular, in humans, this stage lasts from about 2 weeks after fertilization until the end of the seventh or eighth week of pregnancy.


Endocrine

Refers to tissue that makes and releases hormones that travel in the bloodstream and control the actions of other cells or organs. Some examples of endocrine tissues are the pituitary, thyroid, and adrenal glands.


Endocytosis

Incorporation of substances into a cell by phagocytosis or pinocytosis.


Endoplasmic Reticulum

A network of sac-like structures and tubes in the cytoplasm (gel-like fluid) of a cell. Proteins and other molecules move through the endoplasmic reticulum. The outer surface of the endoplasmic reticulum can be smooth or rough. The rough endoplasmic reticulum has many ribosomes on its outer surface and makes proteins the cell needs. The smooth endoplasmic reticulum makes other substances that the cell needs, such as lipids (fats) and carbohydrates (sugars). The endoplasmic reticulum is a cell organelle.


Endoscopic ultrasound-guided fine needle aspiration

A procedure to take a sample of tissue for examination under a microscope. An endoscope with an ultrasound probe and a biopsy needle at the end is inserted through the mouth into the esophagus. An endoscope is a thin, tube-like instrument that has a light and a lens for viewing. The ultrasound probe is used to bounce high-energy sound waves off internal organs and tissues to make a picture on a monitor. This picture helps the doctor see where to place the biopsy needle.


Endothelial Cell

The main type of cell found in the inside lining of blood vessels, lymph vessels, and the heart.


Endothelium

A special name given to the epithelium that lines the circulatory system. This system is lined with a single layer of squamous-type cells.

Endothelium lines the blood vessels and the lymphatic vessels.


Enzyme

A protein that speeds up chemical reactions in the body. Enzymes help speed up chemical reactions in the body and take part in many cell functions, including cell signaling, growth, and division.

An enzyme inhibitor is substance that blocks the action of an enzyme. In cancer treatment, enzyme inhibitors may be used to block certain enzymes that cancer cells need to grow.


Eosinophilia

A condition in which the number of eosinophils (a type of white blood cell) in the blood is greatly increased. Eosinophilia is often a response to infection or allergens (substances that cause an allergic response).


Epidermis

The epidermis is the outer layer of the skin. It is composed of stratified squamous epithelium. It has several layers. The cells of each of these layers change as they move from the basal layer up to the surface of the skin.

  1. Cornified (horny) cell layer (stratum corneum): An outer layer of overlapping flattened scale-like (squamous) remnants of cells which have lost their nuclei and which are filled with keratin, a water-insoluble protein.
  2. Clear-cell layer (stratum lucidum): A thin transparent layer consisting of a substance called eleidin, a precursor of keratin.
  3. Granular-cell layer (stratum granulosoma): A layer of cells containing granules of keratohyalin, an earlier precursor of kertain.
  4. Prickle-cell layer (stratum spinosum).
  5. Basal-cell layer (stratum basale): A layer of actively dividing columnar cells attached to a basement membrane (basal lamina) which marks the junction of the dermis and epidermis.

The keratinized surface-cell remnants are continually worn away or shed while new cells are being formed by the lower layers of the epidermis. As they are formed, they are pushed outward to the surface, gradually flattened, and become filled with keratin. Keratin is a term derived from the Greek work keras meaning "horny."

Melanocytes (pigment cells), located primarily in the basal layer of the epidermis, produce melanin (a dark pigment). The presence of melanin is one of the factors which determine skin color. All individuals except albinos have some melanin in their skins. It is vital for protection against the harmful effect of ultravoilet radiation.


Epithelium

A thin layer of tissue that covers organs, glands, and other structures within the body.


Erythrocyte

A type of blood cell that is made in the bone marrow and found in the blood. Erythrocytes contain a protein called hemoglobin, which carries oxygen from the lungs to all parts of the body. Checking the number of erythrocytes in the blood is usually part of a complete blood cell (CBC) test. It may be used to look for conditions such as anemia, dehydration, malnutrition, and leukemia. Also called RBC and red blood cell.


Erythropoietin

A substance that is naturally produced by the kidneys, and that stimulates the bone marrow to make red blood cells. When erythropoietin is made in the laboratory, it is called epoetin alfa or epoetin beta.


Estrogen

A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones. Estrogens can also be made in the laboratory. They may be used as a type of birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other conditions.


Excisional Biopsy

A surgical procedure in which an entire lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.


Exocytosis

The release of cellular substances (as secretory products) contained in cell vesicles by fusion of the vesicular membrane with the plasma membrane and subsequent release of the contents to the exterior of the cell.


Exophthalmus

An abnormal protrusion of the eyeball(s).


F

Familial adenomatous polyposis

An inherited condition in which numerous polyps (growths that protrude from mucous membranes) form on the inside walls of the colon and rectum. It increases the risk of colorectal cancer.


Fanconi Anemia (congenital pancytopenia)

A rare inherited disorder in which the bone marrow does not make blood cells. It is usually diagnosed in children between 2 and 15 years old. Symptoms include frequent infections, easy bleeding, and extreme tiredness. People with Fanconi anemia may have a small skeleton and brown spots on the skin. They also have an increased risk of developing certain types of cancer.


Fascia

Fascia, a connective tissue, is the packing material of the body. It envelopes the muscles, bones and joints and holds us together supporting the body structure and giving us our shape. Fascia organizes and separates: it provides protection and autonomy for the individual muscles and viscera. It joins and bonds these separate entities and establishes spatial relationships. Chemically it is the collagen in the fascia that enables it to change.


Fertilization

The process of union of two gametes whereby the somatic chromosome number is restored and the development of a new individual is initiated.


Fetus

In humans, an unborn baby that develops and grows inside the uterus (womb). The fetal period begins 8 weeks after fertilization of an egg by a sperm and ends at the time of birth.


Fibroblast

A connective tissue cell that makes and secretes collagen proteins.


Fibrosis

Refers to the presence of scar tissue or collagen fibers in any tissue. In the liver, fibrosis or scarring of the liver damages the architecture and thus the functionality of the organ. Fibrosis, combined with the liver's ability to regenerate, causes cirrhosis (regeneration within the scar tissue).


Fistula

An abnormal opening or passage between two organs or between an organ and the surface of the body. Fistulas may be caused by injury, infection, or inflammation, or may be created during surgery.


Flagellum

A long tapering process that projects singly or in groups from a cell and is the primary organ of motion of many microorganisms.


Flow Cytometry

A method of measuring the number of cells in a sample, the percentage of live cells in a sample, and certain characteristics of cells, such as size, shape, and the presence of tumor markers on the cell surface. The cells are stained with a light-sensitive dye, placed in a fluid, and passed in a stream before a laser or other type of light. The measurements are based on how the light-sensitive dye reacts to the light.


Foramen Magnum

Opening in a bone through which blood vessels, nerves, and/or ligaments pass.


Fossa (pl. fossae)

An anatomical pit, groove, or depression.


Free Radicals

A type of unstable molecule that is made during normal cell metabolism (chemical changes that take place in a cell). Free radicals can build up in cells and cause damage to other molecules, such as DNA, lipids, and proteins. This damage may increase the risk of cancer and other diseases.


Freestanding Facility

A diagnosing or treatment facility (which may or may not be affiliated with or owned by a hospital) that maintains its own patient records. Usually freestanding facilities are in a separate building, such as a surgery or radiation oncology center, and have their own management structure.


Fulguration

A procedure that uses heat from an electric current to destroy abnormal tissue, such as a tumor or other lesion. It may also be used to control bleeding during surgery or after an injury. The electric current passes through an electrode that is placed on or near the tissue. The tip of the electrode is heated by the electric current to burn or destroy the tissue. Fulguration is a type of electrosurgery.


G

Gamma Globulin

Blood plasma proteins like antibodies and complement.


Gamma Ray

A highly energized, deeply penetrating photon that radiates from the nucleus during fission and frequently accompanies radioactive decay.


Ganglion (pl. ganglia)

Non-cancerous, fluid-filled cysts are common masses or lumps in the hand and usually found on the back of the wrist.


Gastrectomy

An operation to remove all (total gastrectomy) or part (partial gastrectomy) of the stomach.


Gastropylorectomy

Excision of the pylorus.


Gastrostomy

The operation of making a permanent opening into the stomach, for the introduction of food. This is done through a gastrotomy tube, which is a tube inserted through the wall of the abdomen directly into the stomach. It allows air and fluid to leave the stomach and can be used to give drugs and liquids, including liquid food, to the patient. Giving food through a gastrostomy tube is a type of enteral nutrition.


Gene

The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.


Glossitis

Inflammation of the tongue.


Glucagon

A hormone produced by the pancreas that increases the level of glucose (sugar) in the blood by increasing the rate of glycogen breakdown in the liver. Produced by the islets of Langerhans.


Glucose

A type of sugar; the chief source of energy for living organisms.


Glycoprotein

A protein that has sugar molecules attached to it.


Goblet Cell

Unicellular glands that secrete mucus. They are interspersed among the epithelial cells that make up mucus membranes.


Goiter

An enlargement of the thyroid gland. It may be caused by too little iodine in the diet or by other conditions. Most goiters are not cancer.

The resulting bulge on the neck may become extremely large, but most simple goiters are brought under control before this happens. Occasionally a simple goiter may cause some difficulty in breathing and swallowing.


Golgi Apparatus

A stack of small flat sacs formed by membranes inside the cell’s cytoplasm (gel-like fluid). The Golgi apparatus prepares proteins and lipid (fat) molecules for use in other places inside and outside the cell. The Golgi apparatus is a cell organelle.


Gonagotropin (adj. Gonadotropic)

A hormone made by a part of the brain called the hypothalamus. Gonadotropin-releasing hormone causes the pituitary gland in the brain to make and secrete the hormones luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In men, these hormones cause the testicles to make testosterone. In women, they cause the ovaries to make estrogen and progesterone.


Granule

A small quantity of a solid substance, smaller than a grain.


Growth Factor

A substance that promotes the growth of cells. Growth factors include epidermal growth factor (EGF), fibroblast growth factor (FGF), erythropoietin (EPO), hematopoietic cell growth factor (HCGF), platelet-derived growth factor (PDGF), stem cell factors, and neurotrophins. Growth factor is produced by normal cells during embryonic development, tisue growth, and wound healing. Tumors, however, produce large amounts of growth factors.


H

HEENT

A HEENT examination is portion of a physical examination, it concerns the Head, Eyes, Ears, Nose and Throat.


Hematocrit

The amount of whole blood that is made up of red blood cells. It depends on the number and size of red blood cells. A hematocrit test is usually part of a complete blood count (CBC). It may be used to check for conditions such as anemia, dehydration, malnutrition, and leukemia.


Hematologic Cancer

Cancer that begins in blood-forming tissue, such as the bone marrow, or in the cells of the immune system. Examples of hematologic cancer are leukemia, lymphoma, and multiple myeloma.


Hemigastrectomy

Excision of the distal one-half of the stomach.


Hemorrhage

In medicine, loss of blood from damaged blood vessels. A hemorrhage may be internal or external, and usually involves a lot of bleeding in a short time.


Hematogenous

Originating in the blood or spread through the bloodstream.


Hemotopoiesis (Adj. Hematopoietic)

The formation of blood or of blood cells in the living body.


Heparin

A substance that slows the formation of blood clots. Heparin is made by the liver, lungs, and other tissues in the body and can also made in the laboratory. Heparin may be injected into muscle or blood to prevent or break up blood clots. It is a type of anticoagulant.


Hepatic flexure

The hepatic flexure is situated between the ascending and the transverse part of the colon, beneath the liver.


Hepatocyte

An epithelial cell of the liver responsible for the synthesis, degradation, and storage of a variety of materials.


Hepatosplenomegaly (HSM)

The simultaneous enlargement of the liver and the spleen.


Hernia

The bulging of an internal organ through a weak area or tear in the muscle or other tissue that holds it in place. Most hernias occur in the abdomen. Hernias may be caused by muscle weakness or straining due to heavy lifting. Hernias can cause extreme pain. Treatment is surgery to remove the hernia.

There are several different types of hernias, including:

  1. Congenital diaphragmatic hernia-a birth defect that needs surgery.
  2. Hiatal hernia-small opening in the diaphragm that allows the upper part of the stomach to move up into the chest.
  3. Incisional hernia-due to a scar.
  4. Inguinal hernia-This is the the most common type and occurs in the groin.
  5. Umbilical hernia-occurs around the belly button.

Hiatal Hernia

A hiatal hernia is a condition in which the upper part of the stomach bulges through an opening in the diaphragm. The diaphragm is the muscle wall that separates the stomach from the chest. The diaphragm helps keep acid from coming up into the esophagus. When there is a hiatal hernia, it's easier for the acid to come up. The leaking of acid from the stomach into the esophagus is called gastroesophageal reflux disease (GERD) .


Hilum

A notch in or opening from a bodily part suggesting the hilum of a bean.


Histamine

A substance that has many effects in the body. It is released from some types of white blood cells during allergic reactions. It causes small blood vessels to dilate (widen) and become leaky, which can cause tissues to swell. It also causes smooth muscles to contract, gastric acid to be made, and the heart rate to increase. Histamine is used in tests for allergies, asthma, and gastric acid secretion. It is a type of neurotransmitter.


Hodgkin Lymphoma

A cancer of the immune system that is marked by the presence of a type of cell called the Reed-Sternberg cell. The two major types of Hodgkin lymphoma are classical Hodgkin lymphoma and nodular lymphocyte-predominant Hodgkin lymphoma. Symptoms include the painless enlargement of lymph nodes, spleen, or other immune tissue. Other symptoms include fever, weight loss, fatigue, or night sweats. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Hypodermis

Loose subcutaneous or connective tissue that is found beneath the skin.

Types of cells found in the hypodermis are: fibroblasts, adipose cells and macrophages.


Hofmeister-Finsterer Operation

Partial gastrectomy with closure of a portion of the lesser curvature and retrocolic anastomosis of the remainder to the jejunum.


Hormonal therapy

Treatment that adds, blocks, or removes hormones. For certain conditions (such as diabetes or menopause), hormones are given to adjust low hormone levels. To slow or stop the growth of certain cancers (such as prostate and breast cancer), synthetic hormones or other drugs may be given to block the body’s natural hormones. Sometimes surgery is needed to remove the gland that makes a certain hormone. It is also called hormone therapy, hormone treatment or endocrine therapy.


Hyaline

Transparent or nearly so and usually homogeneous.


Hydatidiform Mole

A slow-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta) after fertilization of an egg by a sperm. A hydatidiform mole contains many cysts (sacs of fluid). It is usually benign (not cancer) but it may spread to nearby tissues (invasive mole). It may also become a malignant tumor called choriocarcinoma. Hydatidiform mole is the most common type of gestational trophoblastic tumor.


Hypochromic Anemia

Generic term for any type of anemia in which there is a decrease in the number of red blood cells. The red blood cells have less color than normal when examined under a microscope. This is usually due to not enough hemoglobin, which carries oxygen to the red blood cells. The most common causes of anemia are iron deficiency and thalassemia.


I

ICD-9-CM

ICD-9-CM - International Classification of Diseases, Ninth Revision, Clinical Modification. ICD-9-CM is a clinically modified statistical classification system that arranges diseases and injuries into groups according to established criteria. It is based on the ICD-9, which was designed for the classification of morbidity and mortality information for statistical purposes, and published by the World Health Organization (WHO).


ICD-O

The worldwide standard coding system for cancer diagnoses, now in its third edition (ICD-O-3) used worldwide for assigning morbidity and mortality codes to health records and death certificates.


Idiopathic

Describes a disease of unknown cause.


Islets of Langerhans

A pancreatic cell that produces hormones (e.g., insulin and glucagon) that are secreted into the bloodstream. These hormones help control the level of glucose (sugar) in the blood.


Immune System

A complex system of cellular and molecular components having the primary function of distinguishing self from not self and defense against foreign organisms or substances.

The primary cellular components are lymphocytes and macrophages, and the primary molecular components are antibodies and lymphokines; granulocytes and complement system are also involved in immune responses, although they are not always considered as part of the immune system per se.


Immunoglobulin

A protein that is made by B cells and plasma cells (types of white blood cells) and helps the body fight infection. Some immunoglobulins may be found in higher than normal amounts in patients with certain conditions or certain types of cancer, including multiple myeloma and Waldenstrom macroglobulinemia. Measuring the amount of specific immunoglobulins in the blood and urine may help diagnose cancer or find out how well treatment is working or if cancer has come back. Some immunoglobulins may be used as tumor markers.


Immunosuppression

Suppression of the body's immune system and its ability to fight infections and other diseases. Immunosuppression may be deliberately induced with drugs, as in preparation for bone marrow or other organ transplantation, to prevent rejection of the donor tissue. It may also result from certain diseases such as AIDS or lymphoma or from anticancer drugs.


Immunotherapy

A type of biological therapy that uses substances to stimulate or suppress the immune system to help the body fight cancer, infection, and other diseases. Some types of immunotherapy only target certain cells of the immune system. Others affect the immune system in a general way. Types of immunotherapy include cytokines, vaccines, bacillus Calmette-Guerin (BCG), and some monoclonal antibodies.


Incidence

The rate at which a certain event occurs (e.g., the number of new cases of a specific disease occurring during a certain period).

The most important reason for disease registries (such as cancer registries) is determining incidence, for without incidence it is impossible to evaluate the descriptive epidemiology of disease within a population, between populations, and over time.


Incisional Biopsy

A surgical procedure in which a portion of a lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope to check for signs of disease.


Infrared

Denoting thermal radiation of wavelength greater than that of the red end of the spectrum (the recorded band of wavelengths of electromagnetic vibrations of variable light).


Infundibulum

Any of various funnel-shaped organs or parts.


Insulin

A hormone made by the islet cells of the pancreas. Insulin controls the amount of sugar in the blood by moving it into the cells, where it can be used by the body for energy.


Intraepithelial

Within the layer of cells that forms the surface or lining of an organ.


Ionizing radiation

A type of radiation made (or given off) by x-ray procedures, radioactive substances, rays that enter the Earth's atmosphere from outer space, and other sources. At high doses, ionizing radiation increases chemical activity inside cells and can lead to health risks, including cancer.


Ipsilateral

On the same side of the body as another structure or a given point.


Isotope

A form of a chemical element in which the atoms have the same number of protons (part of the nucleus of an atom) but with a different number of neutrons (part of the nucleus of an atom). For example, carbon 12, carbon 13, and carbon 14 are isotopes of carbon. They all have six protons in the nucleus, but each has different number of neutrons. Isotopes may be used in certain medical tests and procedures.

Examples of radioactive isotopes commonly used for isotope-imaging studies are gallium, iodine and technetrium.


K

Kahler Disease

A fatal condition with occurrence of multiple malign tumours disease (multiple myeloma) in the bone marrow, causing disturbances of its function. AKA: Kahler-Bozzolo disease, Bence Jones syndrome, Huppert disease, MacIntyre syndrome, Rustitskii disease, von Rustitskii syndrome.


Kaposi sarcoma

A type of cancer in which lesions (abnormal areas) grow in the skin, lymph nodes, lining of the mouth, nose, and throat, and other tissues of the body. The lesions are usually purple and are made of cancer cells, new blood vessels, and blood cells. They may begin in more than one place in the body at the same time. Kaposi sarcoma is caused by Kaposi sarcoma-associated herpes virus (KSHV). In the United States, it usually occurs in people who have a weak immune system caused by AIDS or by drugs used in organ transplants. It is also seen in older men of Jewish or Mediterranean descent, or in young men in Africa.


Keratin

Type of protein found on epithelial cells, which line the inside and outside surfaces of the body. Keratins help form the tissues of the hair, nails, and the outer layer of the skin. They are also found on cells in the lining of organs, glands, and other parts of the body. The cells are called keratinocytes.

Certain keratins may be found in higher than normal amounts in patients with different types of epithelial cell cancers, including lung, breast, colorectal, bladder, and head and neck cancers. Measuring the amount of specific keratins in the blood may help to plan cancer treatment or find out how well treatment is working or if cancer has come back.

A keratin is a type of tumor marker.


Klinefelter Syndrome

A genetic disorder in males caused by having one or more extra X chromosomes. Males with this disorder may have larger than normal breasts, a lack of facial and body hair, a rounded body type, and small testicles. They may learn to speak much later than other children and may have difficulty learning to read and write. Klinefelter syndrome increases the risk of developing extragonadal germ cell tumors and breast cancer.


L

Lamina Propria

The lamina propria is composed of areolar connective tissue, contains blood vessels, nerves, and, in some regions, glands. It lies just under the epithelium of a mucous membrane.

Once a tumor has broken through the basement membrane into the lamina propria, it can spread by way of the lymphatics and the blood vessels to the other parts of the body.


Leiomyosarcoma

A malignant (cancer) tumor of smooth muscle cells that can arise almost anywhere in the body, but is most common in the uterus, abdomen, or pelvis.


Lesion

An area of abnormal tissue. A lesion may be benign (not cancer) or malignant (cancer).


Leukemia

Cancer that starts in blood-forming tissue, such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the bloodstream.


Ligament

A white, shiny, flexible band of fibrous tissue that binds joints together and connects various bones and cartilage.


Linitis Plastica

A rare type of stomach cancer that begins in the lining of the stomach and spreads to the muscles of the stomach wall. This causes the wall of the stomach to become thick, hard, and rubbery, which leads to trouble digesting food.


Liposarcoma

A rare cancer of the fat cells.


Liver Function Tests (LFTs)

A blood test to measure the blood levels of certain substances released by the liver. A high or low level of certain substances can be a sign of liver disease.


Lumen

The cavity or channel within a tube or tubular organ such as a blood vessel or the intestine.


Lye

A strong caustic alkaline solution of potassium salts, obtained by leaching wood ashes. It is much used in making soap, etc.


Lymph Node

A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels.


Lymphadenopathy (LAD)

Disease or swelling of the lymph nodes.


Lymphangiogram

An x-ray of the lymphatic system. A dye is injected into a lymphatic vessel and travels throughout the lymphatic system. The dye outlines the lymphatic vessels and organs on the x-ray.


Lymphedema

A condition in which extra lymph fluid builds up in tissues and causes swelling. It may occur in an arm or leg if lymph vessels are blocked, damaged, or removed by surgery.


Lymphocyte

A type of immune cell that is made in the bone marrow and is found in the blood and in lymph tissue. The two main types of lymphocytes are B lymphocytes and T lymphocytes. B lymphocytes make antibodies, and T lymphocytes help kill tumor cells and help control immune responses. A lymphocyte is a type of white blood cell.


Lymphocytopenia

Low levels of B-cells, T-cells, and natural killer (NK) cells, which together constitute 30% of white blood cells. B-lymphocytes and T-lymphocytes are responsible for the adaptive immune response, which enables immune system cells to attach to specific antigens on the cell surfaces of infectious organisms, tumors, and other foreign substances.


Lymphoid

Refers to a different cell line of white blood cells (see also myeloid).

Cells derived from stem cells of the lymphoid lineage: large and small lymphocytes, plasma cells.

Lymphoid cells reflect the location from which they derive. These types of cells are found in lymph nodes, GI tract lymphoid tissue, bone marrow.


Lysosome

A sac-like compartment inside a cell that has enzymes that can break down cellular components that need to be destroyed.


M

Macrophage

A phagocytic tissue cell of the reticuloendothelial system that may be fixed or freely motile, is derived from a monocyte, and functions in the protection of the body against infection and noxious substances.


Magnetic Resonance Imaging (MRI)

A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones.


Malaise

Malaise is a generalized feeling of discomfort, illness, or lack of well-being. Malaise is a symptom that can occur with almost any health condition. It may start slowly or quickly, depending on the type of disease. Fatigue (feeling tired) occurs with malaise in many diseases.


Mammography

Mammography is a technique for the detection of breast cancer. In this procedure, several -ray views are taken of one or both breasts and the radiographs are examined for the presence of a lesion. When a lesion is detected, the radiologist often can determine quite accurately whether it is malignant or benign.

Mammography is important because very small, early cancers can be diagnosed with this technique before they are large enough to palpate. Mammograms of the opposite breast should be recorded as well as those of the involved breast. The findings of a mammographic examination will be reported on an x-ray report.


Margin

The edge or border of the tissue removed in cancer surgery. The margin is described as negative or clean when the pathologist finds no cancer cells at the edge of the tissue, suggesting that all of the cancer has been removed. The margin is described as positive or involved when the pathologist finds cancer cells at the edge of the tissue, suggesting that all of the cancer has not been removed.


Mast cell

Cells that play an important role in the body's allergic response. Mast cells are present in most body tissues, but are particularly numerous in connective tissue, such as the dermis (innermost layer) of skin. In an allergic response, an allergen stimulates the release of antibodies, which attach themselves to mast cells. Following subsequent allergen exposure, the mast cells release substances such as histamine (a chemical responsible for allergic symptoms) into the tissue.


Master Patient Index File

The alphabetized, computerized list or card file that includes every patient, alive and dead, who has been accessioned into the registry since the reference date.


Matrix

Ground substance in which things are embedded or that fills a space (as for example the space within the mitochondrion). most common usage is for a loose meshwork within which cells are embedded (e.g. Extracellular matrix), although it may also be used of filters or absorbent material.


Mediastinum

The area between the lungs. The organs in this area include the heart and its large blood vessels, the trachea, the esophagus, the thymus, and lymph nodes but not the lungs.


Megakaryocyte

The giant cell of bone marrow; it is a large cell with a greatly lobulated nucleus, and is generally supposed to give rise to blood platelets.


Melanocytes

A cell in the skin and eyes that produces and contains the pigment called melanin.


Melanoma

Melanoma is the most serious type of skin cancer. Often the first sign of melanoma is a change in the size, shape, color, or feel of a mole. Most melanomas have a black or black-blue area. Melanoma may also appear as a new mole. It may be black, abnormal, or "ugly looking."

Thinking of "ABCDE" can help you remember what to watch for:

  • Asymmetry - the shape of one half does not match the other.
  • Border - the edges are ragged, blurred or irregular.
  • Color - the color is uneven and may include shades of black, brown and tan.
  • Diameter - there is a change in size, usually an increase.
  • Evolving - the mole has changed over the past few weeks or months.

Melatonin

A hormone made by the pineal gland (tiny organ near the center of the brain). Melatonin helps control the body’s sleep cycle, and is an antioxidant. It is also made in the laboratory and sold as a supplement.


Meningioma

Memingiomas, a type of neuroepitheliomatous neoplasms, arise in the meninges, the membranes that envelop the brain and spinal cord: dura mater, pia mater, and arachnoid. These are slow growing tumors and are most always benign. They are rare in children. Meningiomas tend to occur along the superior sagittal sinus, along the sphenoid ridge or in the vicinity of the optic chiasm.


Mesentery

The membranes, or one of the membranes (consisting of a fold of the peritoneum and inclosed tissues), which connect the intestines and their appendages with the dorsal wall of the abdominal cavity. The mesentery proper is connected with the jejunum and ilium, the other mesenteries being called mesoccum, mesocolon, mesorectum, etc.


Mesothelioma

A benign (not cancer) or malignant (cancer) tumor affecting the lining of the chest or abdomen. Exposure to asbestos particles in the air increases the risk of developing malignant mesothelioma.


Metabolism

The chemical changes that take place in a cell or an organism. These changes make energy and the materials cells and organisms need to grow, reproduce, and stay healthy. Metabolism also helps get rid of toxic substances.


Mitochondrion

Any of various round or long cellular organelles of most eukaryotes that are found outside the nucleus, produce energy for the cell through cellular respiration, and are rich in fats, proteins, and enzymes.


Mitosis

The process by which a single parent cell divides to make two new daughter cells. Each daughter cell receives a complete set of chromosomes from the parent cell. This process allows the body to grow and replace cells.

This process starts at mitosis (M-phase) and ends with mitosis. In between are the G-1, S, and G-2 phases. The duration of S, M and G-2 are relatively constant in different tissues.

Between the mitosis phase and the S-phase is a gap (G-1) where production of RNA, proteins and enzymes needed for DNA synthesis occurs. The duration of G-1 varies and determines the length of the cell cycle.

The S-phase is when DNA synthesis occurs.

Between the S-phase and M-phase is a second gap (G-2). Cells are thought to prepare for mitosis in G-2 when specialized proteins and RNA are produced. G-0 is a dormant phase.


Molecule

The smallest particle of a substance that has all of the physical and chemical properties of that substance. Molecules are made up of one or more atoms. If they contain more than one atom, the atoms can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms.


Morbidity

Refers to having a disease or a symptom of disease, or to the amount of disease within a population. Morbidity also refers to medical problems caused by a treatment.


Motor

In medicine, having to do with the movement of body parts.


Mucosa (pl. mucosae)

The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach). Glands in the mucosa make mucus (a thick, slippery fluid).

The mucosa consists of a surface epithelium, a lamina propria, and, in most of the length of the gastrointestinal tract (lower esophagus, stomach, small intestine, colon, and rectum), a muscularis mucosae.


Muscularis Propria

The muscular wall typically made up of two layers of smooth muscle, an inner circular layer and an outer longitudinal layer. It constitutes the wall of the organ.


Myasthenia Gravis (Grave's Disease)

Characterized by the easy tiring of muscles, or muscle weakness. It usually begins in the facial muscles. It is caused by the abnormal destruction of acetylcholine receptors at the neuromuscular junction. This is an autoimmune disorder caused by antibodies that attack acetylcholine receptors.


Mycosis

Any disease caused by a fungus.


Mycosis Fungoides

A type of non-Hodgkin lymphoma that first appears on the skin and can spread to the lymph nodes or other organs such as the spleen, liver, or lungs. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Myelin

The fatty substance that covers and protects nerves.


Myeloid

Having to do with or resembling the bone marrow. May also refer to certain types of hematopoietic (blood-forming) cells found in the bone marrow. Sometimes used as a synonym for myelogenous; for example, acute myeloid leukemia and acute myelogenous leukemia are the same disease.


Myelodysplasia

Covers a group of disorders that result in the inability to produce enough healthy mature blood cells. Those disorders include: acute myeloid leukemia, anemia, chronic myelomonocytic leukemia, leukopenia, myelodysplastic syndromes, refractory anemia, refractory anemia with excess blasts, refractory anemia with ring sideroblasts, and thrombocytopenia.


Myometrium

The muscular outer layer of the uterus.


N

Nausea

A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.


Necrosis

The pathologic death of a cell or group of cells in contact with living cells.


Needle-localized biopsy

A procedure that uses very thin needles or guide wires to mark the location of an abnormal area of tissue so it can be surgically removed. An imaging device is used to place the wire in or around the abnormal area. Needle localization is used when the doctor cannot feel the mass of abnormal tissue.


Neoplasia

Abnormal and uncontrolled cell growth, which may be benign or cancerous, that serves no purpose.


Neoplasm

A "new growth" of the body's own cells, a proliferation of cells no longer under normal physiologic control. These may be "benign" or "malignant."


Nephron

The nephron is the functional unit of the kidney that is responsible for the actual purification and filtration of the blood. About one million nephrons are in the cortex of each kidney, and each one consists of a renal corpuscle and a renal tubule which carry out the functions of the nephron.


Neurilemmomas

Neurilemmomas are a type of nerve sheath tumor that arise from the neur- (nerve) (e)ilemma (covering) which is the thin membrane covering the peripheral nerves, also called the sheath of Schwann. These tumors are usually benign, but may occasionally occur in a malignant form.


Neuroblastoma

Neuroblastoma, a type of neuroepitheliomatous neoplasm, is dervied from the embryonic nerve tissue (neuroblasts) arising primarily in the autonomic nervous system and adrenal medulla, but not in the brain or spinal cord.

Neuroblastoma most often occurs in children younger than 5 years of age. It is thought to begin before birth. It is usually found when the tumor begins to grow and cause signs or symptoms.


Neuroendocrine

Descriptive of cells that release a hormone into the circulating blood in response to a neural stimulus. Such cells may comprise a peripheral endocrine gland (e.g., the insulin-secreting beta cells of the islets of Langerhans in the pancreas and the adrenaline-secreting chromaffin cells of the adrenal medulla); others are neurons in the brain (e.g., the neurons of the supraoptic nucleus that release antidiuretic hormone from their axon terminals in the posterior lobe of the hypophysis).


Neurofibromatosis (Von Recklinghausen disease)

Neurofibromatosis is a genetic disorder of the nervous system. It mainly affects how nerve cells form and grow. It causes tumors to grow on nerves. You can get neurofibromatosis from your parents, or it can happen because of a mutation (change) in your genes. Once you have it, you can pass it along to your children. Usually the tumors are benign, but sometimes they can become cancerous.

There are three types of neurofibromatosis:

  • Type 1 (NF1) causes skin changes and deformed bones. It usually starts in childhood. Sometimes the symptoms are present at birth.
  • Type 2 (NF2) causes hearing loss, ringing in the ears, and poor balance. Symptoms often start in the teen years.
  • Schwannomatosis causes intense pain. It is the rarest type.

Doctors diagnose the different types based on the symptoms. Genetic testing is also used to diagnose NF1 and NF2. There is no cure. Treatment can help control symptoms. Depending on the type of disease and how serious it is, treatment may include surgery to remove tumors, radiation therapy, and medicines.


Neuroglia

Any of the cells that hold nerve cells in place and help them work the way they should. The types of neuroglia include oligodendrocytes, astrocytes, microglia, and ependymal cells.


Neuron

The nerve cell (neuron) is the basic structural and functional unit of the nervous system. Each neuron consists of a cell body which contains a large nucleus surrounded by cytoplasm and processes called dendrites and axons. These process are peculiar to neurons and are responsible for the conduction and transmission of neural information.


Neutron

A neutron is a subatomic particle found in the nucleus of every atom except that of simple hydrogen. The particle derives its name from the fact that it has no electrical charge; it is neutral.


NK (Natural Killer) Cells

A type of immune cell that has granules (small particles) with enzymes that can kill tumor cells or cells infected with a virus. A natural killer cell is a type of white blood cell.

NK cells, like killer T-cells, attack and kill cancer cells and cells infected by microorganisms. NK cells can react against and destroy another cell without prior sensitization to that cell.

Natural killer (NK) cells are part of our first line of defense against cancer cells and virus-infected cells. NK cells are small lymphocytes that originate in the bone marrow.


Non-Hodgkin Lymphoma

Any of a large group of cancers of lymphocytes (white blood cells). Non-Hodgkin lymphomas can occur at any age and are often marked by lymph nodes that are larger than normal, fever, and weight loss. There are many different types of non-Hodgkin lymphoma. These types can be divided into aggressive (fast-growing) and indolent (slow-growing) types, and they can be formed from either B-cells or T-cells. B-cell non-Hodgkin lymphomas include Burkitt lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma, follicular lymphoma, immunoblastic large cell lymphoma, precursor B-lymphoblastic lymphoma, and mantle cell lymphoma. T-cell non-Hodgkin lymphomas include mycosis fungoides, anaplastic large cell lymphoma, and precursor T-lymphoblastic lymphoma. Lymphomas that occur after bone marrow or stem cell transplantation are usually B-cell non-Hodgkin lymphomas. Prognosis and treatment depend on the stage and type of disease. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Notochord

An axial mesodermal tissue found in embryonic stages of all chordates and protochordates, often regressing as maturity is approached. Typically a rod shaped mass of vacuolated cells. It lies immediately below the nerve cord and may provide mechanical strength to the embryo.


Nuclear Medicine

A branch of medicine that uses small amounts of radioactive substances to make pictures of areas inside the body and to treat disease. In cancer, the radioactive substance may be used with a special machine (such as a PET scanner) to find the cancer, to see how far it has spread, or to see how well a treatment is working. Radioactive substances may also be used to treat certain types of cancer, such as thyroid cancer and lymphoma.


O

Omentum

A free fold of the peritoneum, or one serving to connect viscera, support blood vessels, etc. The great, or gastrocolic, omentum forms, in most mammals, a great sac, which is attached to the stomach and transverse colon, is loaded with fat, and covers more or less of the intestines. The lesser, or gastrohepatic, omentum connects the stomach and liver and contains the hepatic vessels. The gastrosplenic omentum, or ligament, connects the stomach and spleen.


Oncologist

A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer treatment.

There are several types of oncologists:

  1. Gynecologic oncologist-Specializes in the treatment of women with GYN cancers, such as uterine or ovarian cancer.
  2. Hematologist-oncologist-Specializes in the diagnosis and treatment of cancers of the blood, such as leukemias, lymphomas, and myelomas.
  3. Medical oncologist-Specializes in treating cancer patients with chemotherapy.
  4. Pediatric oncologist-Specializes in the treatment of children with cancer.
  5. Radiation oncologist-Specializes in treating cancer patients with radiation.
  6. Surgical oncologist-Specializes in treating cancer patients with surgery.

Osmosis

Movement of a solvent through a semipermeable membrane (as of a living cell) into a solution of higher solute concentration that tends to equalize the concentrations of solute on the two sides of the membrane.


Osmotic

Having to do with osmosis (the passage of a liquid through a membrane from a less concentrated solution to a more concentrated one). This causes the more concentrated solution to become diluted, and makes the concentrations in both solutions more equal. Osmotic also refers to a type of laxative that increases the amount of water in the large intestine, which softens the stool to help it pass more easily.


P

Palliative

Palliative means "relief of symptoms." Most often, palliation is the relief of pain.


Pallor

Unnatural lack of color in the skin (as from bruising or sickness or emotional distress)


Pancytopenia

An abnormal deficiency in all blood cells (red blood cells and white blood cells and platelets); usually associated with bone marrow tumor or with aplastic anemia


Panniculitis

Inflammation of subcutaneous fat. Symptoms include skin nodules, which are tender and systemic signs such as weight loss and fatigue.


Pap Smear

A procedure in which a small brush or spatula is used to gently remove cells from the cervix so they can be checked under a microscope for cervical cancer or cell changes that may lead to cervical cancer. A Pap smear may also help find other conditions, such as infections or inflammation. It is sometimes done at the same time as a pelvic exam and may also be done at the same time as a test for certain types of human papillomavirus (HPV).

George Nicolas Papanicolaou, a Greek physician, anatomist, and cytologist in the United States was the inventor of the pap smear, which was named after him.


Papilla (pl. papillae)

Projections of the lamina propria covered with epithelium; produces the rough surface of the tongue.


Parenchyma

The parenchyma is the functional portion of an organ, in contrast to its framework or stroma. For example, the parenchyma of the kidney contains all of the structures which filter and remove waste products from the blood. In general, malignancies tend to arise in the parenchyma of an organ.


Parietal Peritoneum

The peritoneum is a thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal viscera. It is composed of layer of mesthelium supported by a thin layer of connective tissue. Parietal peritoneum is that portion that lines the abdominal and pelvic cavities.


Pathogen

A specific causative agent (such as a bacterium or virus) of disease.


Patency

The state of being freely open or exposed.


Perichondrium

A membrane around the surface of cartilage.


Peritoneum

The serous membrane lining the interior abdominal cavity and investing (covering) the abdominal viscera.


Petechiae

Pin-head-sized sites of bleeding in the skin. This type of bleeding results from a very low platelet count. The small punctate hemorrhages are frequently seen on the legs, feet, trunk and arms. They evolve from red to brown and are eventually disappear. They stop developing when the platelet count increases.


Peyer's patch

Aggregated lymphatic follicles found in the wall of the small intestine.


pH

A measure of acidity and alkalinity of a solution. The measure is a number on a scale on which a value of 7 represents neutrality and lower numbers indicate increasing acidity and higher numbers increasing alkalinity. On the scale, each unit of change represents a tenfold change in acidity or alkalinity.


Phagocyte

A type of immune cell that can surround and kill microorganisms, ingest foreign material, and remove dead cells. It can also boost immune responses. Monocytes, macrophages, and neutrophils are phagocytes. A phagocyte is a type of white blood cell.


Pheochromocytoma

Tumor that forms in the center of the adrenal gland (gland located above the kidney) that causes it to make too much adrenaline. Pheochromocytomas are usually benign (not cancer) but can cause high blood pressure, pounding headaches, heart palpitations, flushing of the face, nausea, and vomiting.


Phenotype

The observable characteristics in an individual resulting from the expression of genes; the clinical presentation of an individual with a particular genotype.


Philadelphia Chromosome

An abnormality of chromosome 22 in which part of chromosome 9 is transferred to it. Bone marrow cells that contain the Philadelphia chromosome are often found in chronic myelogenous leukemia and sometimes found in acute lymphocytic leukemia.


Placenta

The organ that nourishes the developing fetus in the uterus.


Plasma

The liquid component of blood that transports blood cells throughout the body along with nutrients, waste products, antibodies, proteins, and chemical messengers such as hormones.


Plasmacytoma

Localized bone tumor consisting of monoclonal plasma cells. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Platelet

A tiny, disc-shaped piece of cell that is found in the blood and spleen. Platelets are pieces of very large cells in the bone marrow called megakaryocytes. They help form blood clots to slow or stop bleeding and to help wounds heal. Having too many or too few platelets or having platelets that don’t work as they should can cause problems. Checking the number of platelets in the blood may help diagnose certain diseases or conditions. Also called thrombocyte.


Pleomorphic

Occurring in various distinct forms. In terms of cells, having variation in the size and shape of cells or their nuclei.


Pleura

A thin layer of tissue that covers the lungs and lines the interior wall of the chest cavity. It protects and cushions the lungs. This tissue secretes a small amount of fluid that acts as a lubricant, allowing the lungs to move smoothly in the chest cavity while breathing.


Pleural Effusion

An abnormal collection of fluid between the thin layers of tissue (pleura) lining the lung and the wall of the chest cavity.


Plicae Circulares

Plicae circulares are macroscopically visible, crescent-shaped folds of the mucosa and submucosa. Plicae circulares extend around one-half to two-thirds of the circumference of the lumen of the small intestine.


Polypectomy

Surgery to remove a polyp.


Polyvinylchloride

A carcinogenic polymer used in plastics and is commonly known as PVC.


Primary Site

The anatomic site where the original tumor is located. Primary cancer is usually named after the organ in which it starts. For example, cancer that starts in the breast is always breast cancer even if it spreads (metastasizes) to other organs such as bones or lungs.


Process

Any marked prominence or projecting part.


Progesterone

A type of hormone made by the body that plays a role in the menstrual cycle and pregnancy. Progesterone can also be made in the laboratory. It may be used as a type of birth control and to treat menstrual disorders, infertility, symptoms of menopause, and other conditions.


Prognosis

The likely outcome or course of a disease; the chance of recovery or recurrence.


Prolactin

A hormone produced by the anterior lobe of the pituitary gland that is concerned with initialization and maintenance of lactation in the mammary glands. This hormone stimulates the ovary to release the developed ovum and prepares the uterus for implantation of a fertilized ovum. It also stimulates formation of the corpus luteum in the ovary, which secretes progesterone and readies the mammary glands for milk secretion.


Proliferation

Proliferating is the multiplying or increasing in number. In biology, cell proliferation occurs by a process known as cell division.

The proliferating index measures the number of cells in a tumor that are dividing (proliferating). May be used with the S-phase fraction to give a more complete understanding of how fast a tumor is growing.


Proptosis

Forward displacement (bulging) of an organ, typically the eyeball(s).


Protein

A molecule made up of amino acids. Proteins are needed for the body to function properly. They are the basis of body structures, such as skin and hair, and of other substances such as enzymes, cytokines, and antibodies.


Proton

A small, positively charged particle of matter found in the atoms of all elements. Streams of protons generated by special equipment can be used for radiation treatment.


Psoriasis

A chronic disease of the skin marked by red patches covered with white scales.


Puberty

The time of life when a child experiences physical and hormonal changes that mark a transition into adulthood. The child develops secondary sexual characteristics and becomes able to have children. Secondary sexual characteristics include growth of pubic, armpit, and leg hair; breast enlargement; and increased hip width in girls. In boys, they include growth of pubic, face, chest and armpit hair; voice changes; penis and testicle growth, and increased shoulder width.


Puerperium

The period between childbirth and the return of the uterus to its normal size.


Purpura

Hemorrhage under a surface that is about 1.0 cm. in diameter.


Pyelogram

X-ray study of the kidney especially showing the pelvis (urine-collecting basin) of the kidney and the ureter.


R

Radioactive Isotope

A radioactive form of iodine, often used for imaging tests or to treat an overactive thyroid, thyroid cancer, and certain other cancers. For imaging tests, the patient takes a small dose of radioactive iodine that collects in thyroid cells and certain kinds of tumors and can be detected by a scanner. To treat thyroid cancer, the patient takes a large dose of radioactive iodine, which kills thyroid cells. Radioactive iodine is also used in internal radiation therapy for prostate cancer, intraocular (eye) melanoma, and carcinoid tumors. Radioactive iodine is given by mouth as a liquid or in capsules, by infusion, or sealed in seeds, which are placed in or near the tumor to kill cancer cells.


Radiotherapy

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiotherapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body.


Refractory

In medicine, describes a disease or condition that does not respond to treatment.


Reportable List

Identifies all diagnoses and types of cases to be included in the cancer registry database and should also specify which diagnoses are nonreportable.


Reportable Malignancies

Tumors required to be reported. Typically, in most cancer registries, the reportable tumors are those that are listed in the International Classification of Diseases for Oncology, Third Edition which have a behavior defined as in situ (behavior code = /2) or invasive (behavior code = /3).


Retroperitoneal

Located behind the peritoneum, the membrane that lines the abdominopelvic walls and forms a covering for the internal organs.


Residual Disease

Cancer cells that remain after attempts to remove the cancer have been made.


Reticuloendothelial system

The reticuloendothelial (RE) system consists of those specialized connective tissue cells that do phagocytosis. Three types of cells fit into this category.

The first types are the RE cells that line the liver (Kupffer's cells) and those that line the spleen and bone marrow.

The second type are the macrophages . These cells are also referred to as histiocytes or "resting, wandering" cells, because they are fixed in tissue until they must wander to an invader and devour it. Any pahgocytic cells of the re system can be called a macrophage.

The third type of cell is a neuroglia which does support and a microglia cells. This is a phagocytic cell found in the central nervous system. Other types of neuroglia cells do support.


Retinoblastoma

Cancer that forms in the tissues of the retina (the light-sensitive layers of nerve tissue at the back of the eye). Retinoblastoma usually occurs in children younger than 5 years. It may be hereditary or nonhereditary (sporadic).


Rhabdomyosarcoma

Rhabdomyosarcoma tumors arise from a cell called a "rhabdomyoblast", which is a primitive muscle cell. Instead of differentiating into striated muscle cells, the rhabdomyoblasts grow out of control. Since this type of muscle is located throughout the body, the tumors can appear at numerous locations.


Ribosome

In biology, a structure found inside cells that is involved in making proteins. Ribosomes help link amino acids together to form proteins.


Roentgen

The international unit of x- or gamma-radiation, abbreviated r or R; named after the German physicist, Wilhelm Roentgen, who discovered roentgen ray in 1895.


Rubric

A rubric is a chart or template which specifies the criteria to be used to evaluate an assignment.


S

Serum

The clear liquid part of the blood that remains after blood cells and clotting proteins have been removed. Serum is essentially blood plasma from which fibrinogen has been removed in the process of clotting.


Sarcoma

A type of cancer that begins in bone or in the soft tissues of the body, including cartilage, fat, muscle, blood vessels, fibrous tissue, or other connective or supportive tissue. Different types of sarcoma are based on where the cancer forms. For example, osteosarcoma forms in bone, liposarcoma forms in fat, and rhabdomyosarcoma forms in muscle. Treatment and prognosis depend on the type and grade of the cancer (how abnormal the cancer cells look under a microscope and how quickly the cancer is likely to grow and spread). Sarcoma occurs in both adults and children.


Sclerosis

A hardening within the nervous system, especially of the brain and spinal cord, resulting from degeneration of nervous elements such as the myelin sheath.


Sebaceous

Of, relating to, or being fatty material.


Sézary Disease

Sézary syndrome is an aggressive form of a type of cancer called cutaneous T-cell lymphoma. Cutaneous T-cell lymphomas occur when certain immune cells, called T cells, become cancerous; these cancers characteristically affect the skin, causing different types of skin lesions. In Sézary syndrome, the cancerous T cells are called Sézary cells and are found in the skin, lymph nodes, and blood. A characteristic of Sézary cells is an abnormally shaped nucleus, described as cerebriform. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.


Shared Follow-up

Shared follow-up is the act or process of sharing information or contacting the patient at least once per year to ascertain vial status, cancer status, and other information.


Sideroblast

An erythroblast having granules of ferritin


Signet Ring

The early stage of trophozoite development of the malaria parasite in the red blood cell; the parasite cytoplasm stains blue around its circular margin, and the nucleus stains red in Romanowsky stains, while the central vacuole is clear, giving the ringlike appearance.


Sinoatrial Node

The beginning of the conduction system of the heart. The sinoatrial node (SA node) initiates each cardiac cycle and sets the pace for the heart rate.

The SA node is located in the superior wall of the right atrium. It can be modified by nerve impulses from the autoimmune nervous system; sympathetic impulses will speed it up and parasympathetic impulses will restore or slow it down. Thyroid hormones and epinephrine carried by the blood will also affect the SA node (pacemaker).

Once an impulse is initiated by the SA node, the impulse spreads out over both atria, causing them to contract simultaneously.


Sister Mary Joseph node (Sister Joseph node)

A malignant intra-abdominal neoplasm metastatic to the umbilicus.


Sphincter

A ring-shaped muscle that relaxes or tightens to open or close a passage or opening in the body. Examples are the anal sphincter (around the opening of the anus) and the pyloric sphincter (at the lower opening of the stomach).


Splenomegaly

Enlargement of the spleen.


Squamous cell carcinoma

Cancer that begins in squamous cells. Squamous cells are thin, flat cells that look like fish scales, and are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the lining of the respiratory and digestive tracts. Most cancers of the anus, cervix, head and neck, and vagina are squamous cell carcinomas.


Staging

Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from the original site to other parts of the body. It is important to know the stage of the disease in order to plan the best treatment.


Stem Cell

A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells.


Stenosis

A narrowing, as in aortic stenosis (narrowing of the aortic valve in the heart), pulmonary stenosis (narrowing of the pulmonary valve in the heart), pyloric stenosis (narrowing of the outlet of the stomach), spinal stenosis (narrowing of the vertebral canal, often with impingement upon the spinal cord).From the Greek "stenos" meaning narrow.


Stereotactic Biopsy

A biopsy procedure that uses a computer and a 3-dimensional scanning device to find a tumor site and guide the removal of tissue for examination under a microscope. This approach is often used to diagnose brain tumors or other disorders. CT or MRI guidance is used.


Steroid

Any of a group of lipids (fats) that have a certain chemical structure. Steroids occur naturally in plants and animals or they may be made in the laboratory. Examples of steroids include sex hormones, cholesterol, bile acids, and some drugs.


Stromal Cells

Connective tissue cells of an organ found in the loose connective tissue. These are most often associated with the uterine mucosa and the ovary as well as the haematopoietic system and elsewhere.


Subcutis

The deepest layer of the dermis.


Sulcus

A groove or furrow, as one of the grooves on the surface of the cerebrum in mammals.


Surgicel

A hemostatic agent (blood-clot-inducing material) made of an oxydized cellulose polymer. It is used mostly to control bleeding.


T

T-cells

A type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells. They are produced in the bone marrow and mature in the thymus. T-cells produce a number of substances that regulate the immune response.

T-cells are the most common type of lymphocyte. T-cells divide into at least three sub-populations on the basis of function.

  1. Cytotoxic or killer cell T-lymphocytes.
  2. Helper T-lymphocytes.
  3. Suppressor T-lymphocytes.

Technetium

A silvery-grey metallic element, artificially produced by bombardment of molybdenum by deuterons: used to inhibit corrosion in steel. The radioisotope technetium (Tc99m), with a half-life of six hours, is used in radiotherapy.


Teratoma

A type of germ cell tumor that may contain several different types of tissue, such as hair, muscle, and bone. Teratomas occur most often in the ovaries in women, the testicles in men, and the tailbone in children. Not all teratomas are malignant.


Testosterone

A hormone made mainly in the testes (part of the male reproductive system). It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. Testosterone may also be made in the laboratory and is used to treat certain medical conditions.


Tetraploid

Having four times the haploid number of chromosomes in the cell nucleus.


Thoracentesis

Removal of fluid from the pleural cavity through a needle inserted between the ribs.


Thyroxine

A hormone that is made by the thyroid gland and contains iodine. Thyroxine increases the rate of chemical reactions in cells and helps control growth and development. Thyroxine can also be made in the laboratory and is used to treat thyroid disorders. Also called L-3,5,5’-tetraiodothyronine, T4, and thyroxin.


Tinnitus

A disorder in which a person hears noises such as buzzing, ringing, clicking, or the sound of a pulse, when no outside sound is causing them. Tinnitus may have many different causes, and may be a symptom of another disease or condition. It may be caused by certain tumors and anticancer drugs.


Toluene

A strong-smelling, colorless liquid used to make gasoline and other types of fuel, paint, paint thinner, fingernail polish, glue, and rubber. Being exposed to toluene may cause headache, tiredness, confusion, weakness, memory loss, nausea, loss of appetite, hearing and color vision loss, dizziness, loss of consciousness, kidney damage, and death.


Trephine

A surgical tool used to cut out circular pieces of bone or other tissue.


Triiodothyronine

A thyroid hormone.


Tumor Markers

A substance found in tissue, blood, or other body fluids that may be a sign of cancer or certain benign (noncancerous) conditions. Most tumor markers are made by both normal cells and cancer cells, but they are made in larger amounts by cancer cells. A tumor marker may help to diagnose cancer, plan treatment, or find out how well treatment is working or if cancer has come back. Examples of tumor markers include CA-125 (in ovarian cancer), CA 15-3 (in breast cancer), CEA (in colon cancer), and PSA (in prostate cancer).


U

Ultrasound

A procedure that uses high-energy sound waves to look at tissues and organs inside the body. The sound waves make echoes that form pictures of the tissues and organs on a computer screen (sonogram). Ultrasound may be used to help diagnose diseases, such as cancer. It may also be used during pregnancy to check the fetus (unborn baby) and during medical procedures, such as biopsies.


Umbilical Cord

A cord arising from the navel that connects the fetus with the placenta.


V

Vagus Nerve

A pair of nerves that carries sensory information from the throat and windpipe to the brain, and controls the muscles of the throat, windpipe, heart, lungs, stomach, bowels and part of the ear. Originates in the medulla oblongata.


Vascular

Relating to the veins and arteries that carry substances, e.g., blood, throughout the body.


Venous

Venous refers to the system or veins by which blood is returned to the lungs for oxygenation.


Vertigo

Illusion of movement; sensation that the external world is revolving around an individual (objective vertigo) or that the individual is revolving in space (subjective vertigo).


Villus (pl. villi)

A tiny hair-like projection, often on the surface of mucous membranes. The plural is villi.


Virchow node (jugular gland, signal node)

A firm supraclavicular lymph node, especially on the left side, sufficiently enlarged that it is palpable from the cutaneous surface.

Lymph node is so termed because it may be the first recognized presumptive evidence of a malignant neoplasm in one of the viscera. A signal node that is known to contain a metastasis from a malignant neoplasm is sometimes designated by an old eponymn, Troisier ganglion.


Virus

In medicine, a very simple microorganism that infects cells and may cause disease. Because viruses can multiply only inside infected cells, they are not considered to be alive.


Viscosity

The resistance offered by a fluid (liquid or gas) to flow. The viscosity is a characteristic property and is a measure of the combined effects of adhesion and cohesion. Hyperviscosity syndrome: Blood too thick to flow properly.


Vitamin

A nutrient that the body needs in small amounts to function and stay healthy. Sources of vitamins are plant and animal food products and dietary supplements. Some vitamins are made in the human body from food products. Vitamins are either fat-soluble (can dissolve in fats and oils) or water-soluble (can dissolve in water). Excess fat-soluble vitamins are stored in the body’s fatty tissue, but excess water-soluble vitamins are removed in the urine. Examples are vitamin A, vitamin C, and vitamin E.


W

WNL

A standard abbreviation for W ithin N ormal L imits.


Waldenstrom's Macroglobulinemia

An indolent (slow growing) type of non-Hodgkin lymphoma marked by abnormal levels of IgM antibodies in the blood and an enlarged liver, spleen, or lymph nodes. For more information, see the hematopoietic database at https://seer.cancer.gov/seertools/hemelymph/.

This is a clinical diagnosis, not a pathology diagnosis. Most cases are associated with lymphoplasmacytic lymphoma, but occasionally it is associated with other subtypes of non-Hodgkin lymphoma.


Waldeyer ring

The lymphoid ring of the nasopharynx. A ring of lymphoid tissue that encircles the nasopharynx and oropharynx. It is formed by the lymphatic tissue of the pharynx, the palatine tonsil, and the lingual tonsil, as well as other collections of lymph tissue in the area.


Wilms Tumor

A disease in which malignant (cancer) cells are found in the kidney, and may spread to the lungs, liver, or nearby lymph nodes. Wilms tumor usually occurs in children younger than 5 years old.


X

Xeroderma Pigmentosum

A genetic condition marked by an extreme sensitivity to ultraviolet radiation, including sunlight. People with xeroderma pigmentosum are not able to repair skin damage from the sun and other sources of ultraviolet radiation, and have a very high risk of skin cancer.