- Last Update On : 2013-01-01
The most commonly used breast cancer mucin assay is designated CA 15.3. CA 15.3 is not specific for breast cancer because levels are also increased in patients with gastric, colorectal, lung, pancreas, ovarian, uterine, and cervical cancers. Levels are also elevated in a few healthy women, 10% of patients with benign breast diseases, and 40% of patients with inflammatory liver diseases. CA 15.3 levels are not elevated during pregnancy or lactation.
CA 15.3 is not very sensitive in detecting early breast cancer; only 5 to 30% of patients with stage I and II cancer have elevated levels. CA 15.3 is not very useful in the differential diagnosis of breast masses, since it is elevated in some benign breast diseases and often not elevated in early breast cancer. CA 15.3 levels do not correlate with known prognostic factors, such as histologic grade, receptor status, or age. It does not have prognostic value for predicting which patients with metastatic disease will respond to thera