Biomarkers in Breast Cancer: Current Practice, Opportunities and Unmet Needs

Biomarkers are essential to define breast cancer subtypes that predict prognosis and guide treatment and to guide selection of Rx in metastatic disease. 94% of breast cancer is curable and biomarkers play a critical role in identifying patients with early stage cancer who may benefit from novel therapies. Biomarkers can be useful in evaluation of symptoms in survivors but should not be used in asymptomatic survivors outside of a clinical trial. More research is needed to identify high risk patients who can be targeted for early intervention and improved outcomes. Biomarkers may be used as one of the tools to evaluate response to Rx and may be used to individualize therapy and guide decisions over chemotherapy. Examples of validated and commonly used tumor markers in oncology include PSA for prostate cancer, M protein for Myeloma, HCG for some testicular cancers. Biomarkers are used to guide therapy in metastatic breast cancer. ASCO guidelines recommend biopsy to confirm diagnosis and check standard clinical biomarkers (ER, PR, and HER2) to guide therapy. Decisions on changing to a new drug or discontinuing treatment should be based on the patient's goals for care and clinical evaluation of disease progression or response. There is no evidence that changing therapy solely based on biomarker results improves health outcome, quality of life, or cost effectiveness. Biomarkers may be used as one of the tools to evaluate response to Rx. Liquid biopsy as early screening of response and guide to precision therapy is the future.

Learning Objectives:

• The role of biomarkers in predicting breast cancer
• Learn about liquid biopsy and how it’s used in breast cancer screening and monitoring.