Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (779 page)

   
Normal value:
<38.6 U/mL

   Use

   As an aid in monitoring patients previously treated for stage II or III breast cancer.

   Interpretation

Increased In

   One third of early stage I and II breast cancers and two thirds of later stage III and IV breast cancers

   Associated malignancies: colon, gastric, hepatic, lung, pancreatic, ovarian, and prostate cancers

   Benign conditions: breast, liver, and kidney disorders; ovarian cysts, tuberculosis, sarcoidosis, endometriosis, SLE, lactation, and pregnancy

   Limitations

   Lacks predictive value in early-stage breast cancer and thus has no role in screening for or diagnosis of the malignancy.

   The concentration of CA 27.29 in a given specimen can vary because of differences in assay methods and reagent specificity. Values obtained with different assay methods should not be used interchangeably.

   Levels of CA 27.29 should not be interpreted as absolute evidence of the presence or the absence of malignant disease. Measurements of CA 27.29 should always be used in conjunction with other diagnostic procedures.

CANCER ANTIGEN-125 (CA-125), SERUM

   Definition

   CA-125 is a large glycoprotein (200–1,000 kDa) found on the surface of many ovarian cancer cells and in some normal tissues. It is a product of the
MUC16
gene.