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Tumor Markers

Key Information

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

CA-125 (Cancer Antigen-125)

A tumor marker useful for monitoring ovarian cancer by measuring an antigen to epithelial neoplasms circulating in blood serum.

Normal range:
0 - 35 U/mL. Normal range may vary somewhat according to institutional experience. Levels above 35 suggest the presence of ovarian tumor.

CEA (Carcinoembryonic Antigen)

A blood test measuring the presence of an antigen in malignancies arising in entodermal (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.

For germ cell tumors

Alpha-fetoprotein: A serum test used as a tumor marker for teratoma or embryonal carcinoma of the ovary. Elevated alpha-fetoprotein levels are not found in other histologies of ovarian cancer, although they may be found in patients with hepatocellular cancer. Note: Observe the date of an alpha-fetoprotein study carefully. Record a pre-operative study only. Alpha-fetoprotein is also used as a marker postoperatively to monitor residual tumor. Also called: aFP, AFP, alpha-fetoglobulin.

Normal range:
Adults: < 15 ng/ml.

Beta Subunit HCG (Human Chorionic Gonadotropin):

A serum test used as a tumor marker for germ cell ovarian carcinoma. When the presence of B-HCG is detected in serum it always indicates a malignancy. Also called: ?-HCG, beta-HCG, beta chain HCG. 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 germ cell ovarian cancer who have had an 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/ml.

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