ASCO Recommends Biomarker Use to Guide Early Breast Cancer Therapy Decisions

The American Society of Clinical Oncology (ASCO) today issued a new clinical practice guideline for women with early-stage invasive breast cancer and known hormone receptor and human epidermal growth factor 2 (HER2) receptor status.

The 13 panel members—with expertise in medical oncology, radiation oncology, community oncology, statistics, and health outcome researchers—conducted a literature review of relevant studies published during the period between 2006 and 2014 that included overall survival and disease-free or recurrence-free survival as the measured outcomes. A cancer survivor on the panel represented the patient perspective. The review narrowed down the search to 50 relevant papers, which included 1 randomized trial and 18 prospective-retrospective studies that evaluated clinical utility of specific biomarkers as a guide for decisions on adjuvant systemic therapy.

Published in the Journal of Clinical Oncology, the guideline looks to answer the following questions:

1. For women with early-stage invasive breast cancer and with known estrogen and progesterone receptor (ER/PgR) and HER2 status, which other biomarkers have demonstrated clinical utility to guide decisions on the need for adjuvant systemic therapy?
2. For women with early-stage invasive breast cancer and with known ER/PgR and HER2 status, which additional biomarkers have demonstrated clinical utility to guide choice of specific drugs or regimens for adjuvant systemic therapy?

The following are the primary guideline recommendations:

• The following biomarker tests may be used to guide decisions on adjuvant systemic therapy for certain patients with breast cancer: estrogen receptor, progesterone receptor, HER2 receptor, Oncotype DX, EndoPredict, PAM50, Breast Cancer Index, and urokinase plasminogen activator and plasminogen activator inhibitor type 1.
• No biomarker test, except for estrogen receptor, progesterone receptor, and HER2 receptor should be used to guide choices of specific drugs or treatment regimens.
• Treatment decisions should also consider disease stage, comorbidities and patient preferences.

In a press statement released with the guidelines, Lyndsay N. Harris, MD, co-chair of the ASCO expert panel that developed the guideline said, “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 5-10 years, but not all have sufficient evidence of clinical utility. 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.”