Tumor Markers of Breast Cancer: Role in Early Diagnosis, Monitoring Response to Therapy and Determination of Prognosis

A tumor marker is a substance that is produced by the body in response to malignant tumors, or produced by the cancer itself. Some of these markers are specific to one cancer, while others are seen in several types of cancer. These markers are generally used to evaluate the patient's response to treatment or to monitor the presence of metastasis or recurrence. Breast cancer is one of the most common malignancies in females worldwide. Tumor markers may play a role in early detection, and hence favourable prognosis of breast cancer. The CA 27-29 is a tumor marker that is most often used in people with breast cancer. Also, CA 15-3, BR 27.29 (CA27.29), carcinoembryonic antigen (CEA), tissue polypeptide specific antigen, p53, cathepsin D, cyclin E, nestin and HER-2 are widely used for diagnosis, monitoring response to therapy, early detection of metastasis and determination of recurrence of breast cancer.