Abstract
Biomarkers offer great promise in the care of patients who have cancer. They can establish a more accurate and definitive diagnosis, and help identify patients most likely to respond to therapy, those most likely to experience disease recurrence, or those most likely to suffer toxicity. Predictive markers are associated with response, or lack thereof, to a particular treatment. Prognostic markers are baseline measurements that project a disease trajectory. No longer limited to measurement of serum-based proteins, the types of biomarkers now available in oncology practice are exceedingly diverse, ranging from assays of circulating factors in the peripheral blood of patients who have cancer to specialized molecular or genetic analyses of the tumor tissue itself. In 2007 the American Society of Clinical Oncology (ASCO) updated their recommendations for the use of tumor marker tests in the prevention, screening, treatment, and surveillance of breast cancer. This article will include predictive, prognostic, and current ASCO recommendations for breast cancer markers. Additionally, emerging biomarkers will be explored. Many of these may show great promise in the quest to personalize care for patients with breast cancer.
