Cancer Antigen CA 27.29


For: ,

Quest Diagnostics Test Code: 29493

CA 27.29 is used for monitoring patients for metastatic breast cancer.

Cancer antigen (CA) 27.29 is a type of glycoprotein that is typically found on the surface of epithelial cells, like breast cancer cells. When there is breast cancer, there is rapid growth of breast cells, which sheds CA 27.29 into the bloodstream and can be measured. Because of this, it is helpful in guiding the efficacy of treatment in women with breast cancer. However, because this increase in CA 15-3 production is not present in all women with breast cancer, it is not a useful screening tool or for diagnosis to detect breast cancer in women. Therefore, the test is mainly used as a surveillance tool in women who already have a diagnosis and are on treatment to see if the treatment is effective or to detect metastatic disease.

This test is performed in following conditions such as:

• In people who already have breast cancer diagnosed, this is to help determine cancer characteristics and treatment options
• Women with breast cancer who are on treatment like radio or chemotherapy


There are no special requirements for this test.


Specimen Collected
  • Blood
Estimated Time Taken

The typical turnaround for this test is 2-4 business days.