Review: What Is Cancer?

Here is what we have learned from What Is Cancer?:

• The American Cancer Society defines cancer as "a group of diseases characterized by uncontrollable growth and spread of abnormal cells. If the spread is not controlled, it can result in death."
• Cancer does not refer to a single disease. Rather, it consists of more than 100 different diseases.
• A few cancer-related terms are introduced: cancer, neoplasia, tumor, neoplasm, and growth. Neoplasia, a synonym of cancer, is often used by medical professionals. Neoplasm is a synonym for tumor, which literally means "new growth." Several other terms referring to abnormal cell growth which are not cancer include: hyperplasia, metaplasia, and dysplasia.
• Cell biology of cancer defines the differences between normal cells and cancer cells. Normal, healthy cells carry out specific functions of the body and the cells' growth is controlled by a complicated biochemical mechanism of the body. Cancer cells grow in an uncontrollable manner and are unable to recognize their own natural boundaries due to faulty gene mutations in the cancer cells.
• Although scientists have not yet pinpointed an exact cause for cancer, many factors have been identified that are likely to cause development of cancer in the body. These factors are called "cancer risk factors" and include smoking, diet, genetics, occupation, environment, and infectious agents.