A new clinical practice guideline on the appropriate use of tests for breast tumor biomarkers was issued by the American Society of Clinical Oncology (ASCO). The goal is to guide decisions on adjuvant systemic therapy for women with early-stage invasive breast cancer and known status for hormone receptor and human epidermal growth factor 2 (HER2) receptor. The guideline was published in the Journal of Clinical Oncology.1
“In the era of precision medicine, the role of biomarkers in guiding clinical care is greater than in the past. An extensive number of new tests have come out in the last 5 to 10 years, but not all have sufficient evidence of clinical utility,” said Lyndsay N. Harris, MD, co-chair of the ASCO expert panel that developed the guideline. “These latest recommendations truly inform physicians about which tests need to be performed. But this is not all that goes into patient care. Doctors need to continue discussions with patients to develop individualized treatment plans.”
An expert panel systematically reviewed literature published from January 2006 to September 2015, identifying 50 relevant studies, to develop the guidelines. The multidisciplinary panel represented expertise in medical oncology, radiation oncology, community oncology, statistics, and health outcomes, along with a cancer survivor who provided a patient perspective.
The guidelines state that decisions on systemic adjuvant therapy for certain patients with breast cancer can be guided by these biomarker tests: estrogen receptor, progesterone receptor, HER2 receptor, Oncotype DX, EndoPredict, PAM50, Breast Cancer Index, and urokinase plasminogen activator and plasminogen activator inhibitor type 1.
The guidelines also state that choosing specific drugs or treatment regimens should be guided only by biomarker tests for estrogen receptor, progesterone receptor, and HER2 receptor. No other biomarker was found to guide choices of specific treatments or regimens.
When treatment decisions are made, the decisions should consider disease stage, comorbidities, and patient preferences.
The guidelines describe each of their recommendations with information on the type of recommendation, its evidence quality, and the strength of the recommendation.
The guidelines also state the need to possibly modify the guidance for patients with multiple chronic conditions.
The guideline publication concluded that more research is needed to refine and redefine the clinical utility of specific biomarkers. Both prospective biomarker investigations when clinical trials are begun and prospective or retrospective studies to validate the clinical utility of biomarkers are important.
1. Harris LN, Ismaila N, McShane LM, et al. Use of biomarkers to guide decisions on adjuvant systemic therapy for women with early-stage invasive breast cancer: American Society of Clinical Oncology Clinical Practice Guideline [published online ahead of print February 8, 2016]. J Clin Oncol. doi:10.1200/JCO.2015.65.2289. Accessed February 16, 2016.