CA 27.29 is a protein that has increased its concentration in some situations, mainly in the recurrence of breast cancer, and is therefore considered a tumor marker.
This marker has practically the same characteristics as the CA 15.3 marker, however it is more advantageous with respect to the early diagnosis of recurrence and non-response to treatment against breast cancer.
What is it for
The CA 27-29 exam is usually requested by the physician to follow patients previously diagnosed with stage II and stage III breast cancer who have already started treatment. Thus, this tumor marker is required to identify early breast cancer recurrence and response to treatment, with 98% specificity and 58% sensitivity.
Although it has good specificity and sensitivity regarding the identification of recurrence, this marker is not specific when it comes to the diagnosis of breast cancer and should be used in conjunction with other tests, such as the CA 15-3 marker, AFP and CEA, and mammography. See the exams that detect breast cancer.
How is done
The CA 27-29 examination is done by collecting a small blood sample at a suitable facility, and the sample should be sent to the laboratory for analysis.
The reference value depends on the analysis methodology, which may vary according to the laboratories, with the normal reference value being less than 38 U / mL.
What may be the result changed
Results above 38 U / mL are usually indicative of recurrence of breast cancer or possibility of metastasis. In addition, it may indicate that treatment is being resisted, requiring the physician to reassess the patient to establish another therapeutic approach.
Values may also be altered in other cancers, such as ovarian, cervical, kidney, liver and lung cancer, as well as other benign conditions such as endometriosis, ovarian cysts, benign breast disease, kidney stones and liver disease. Thus, for the diagnosis of breast cancer to be possible, the physician usually requests complementary examinations, such as mammography and the CA 15.3 marker. Learn more about the CA 15.3 exam.