Tumor Markers

Key Information

Evaluating tumor volume in the body; primarily used for monitoring recurrence

CEA (Carcinoembryonic Antigen)

A blood test measuring the presence of an antigen in malignancies arising in endodermal (embryonic) or gastrointestinal tissue. CEA assay is nonspecific for identifying a primary site, but it does indicate the presence of malignancy. Smokers may have an elevated CEA without malignant disease.

Normal range: < 2.5 ng/ml. Normal range may vary somewhat according to institutional experience. Levels > 10 ng/ml suggest extensive disease and levels > 20 ng/ml suggest metastatic disease.

TPA (Tissue Polypeptide Antigen)

An antigen marker for cancers of gynecologic sites, bladder, and lung; nonspecific to ovarian cancer; elevated levels indicate presence of malignancy

Estrogen Receptor Assay (ERA)

A laboratory test to determine the responsiveness of the tumor to endocrine therapy or to removal of the ovaries. Tumors which are negative for estrogen receptors rarely respond to hormone manipulation; about 55 % of ER positive tumors will respond to endocrine therapy. The unit of measurement is femtomoles (fmoles) per milligram of tumor.

Types of ERA:

• Quantified (measured in femtomoles or fmoles)
• Immunohistochemical—a qualitative measurement of the observed number of hormone responsive cells, reported as positive or negative.

Test results—negative: 3 fmoles or less. ERA may not be performed if tumor is less than 1.0 cm in size or if tumor is completely in situ.

Progesterone Receptor Assay (PRA)

A laboratory test to determine the responsiveness of the tumor to endocrine therapy or to removal of the ovaries. Progesterone receptor assay increases the reliability of estrogen receptor assay results: a positive progesterone receptor assay indicates greater likelihood that the patient will respond to hormone therapy. The unit of measurement is femtomoles (fmoles) per milligram of tumor.

• Quantified (measured in femtomoles or fmoles)
• Immunohistochemical—a qualitative measurement of the observed number of hormone responsive cells, reported as positive or negative.

Test results—negative: 5 fmoles or less. Test may not be performed if tumor is less than 1.0 cm in size or if tumor is completely in situ.

For Placental Tumors

Beta Subunit HCG (human chorionic gonadotropin)

A serum test used as a tumor marker for choriocarcinoma. When the presence of B-H CG is detected in serum it always indicates a malignancy. Also called: ß-HCG, beta-HCG, beta chain H-CG. Note: Observe the date of the beta-HCG study carefully. Record a pre-operative study only. Beta-HCG is also used as a marker postoperatively to monitor residual tumor and the effectiveness of therapy. In patients with choriocarcinoma who have had a hysterectomy and oophorectomy, the presence of beta-HCG will confirm the patient has residual cancer that requires further treatment. However, when beta-HCG does not exist in the serum, the presence of active cancer cannot be excluded, especially in patients who have been previously treated.
Normal range: 0 ng/m l.

Liver Function Tests (LFT)

A series of blood chemistry tests measuring enzymes excreted by the liver during abnormal functioning due to metastases, obstruction or other conditions. Also called: liver panel. A liver panel may
contain any of the following tests. If any one of these tests is outside the normal range of values, the test should be reported as abnormal.

Click here to view the Tumor Markers page of the Diagnostic Tests module for more information.