Role of Patient and Disease Factors in Adjuvant Systemic Therapy Decision Making for Early-Stage, Operable Breast Cancer: American Society of Clinical Oncology Endorsement of Cancer Care Ontario…

N Lynn Henry, Mark R Somerfield, Vandana G Abramson, Kimberly H Allison, Carey K Anders, Diana T Chingos, Arti Hurria, Thomas H Openshaw, Ian E Krop

An American Society of Clinical Oncology (ASCO) panel considered the Cancer Care Ontario (CCO) recommendations on the role of patient and disease factors in selecting adjuvant therapy for women with early-stage breast cancer for endorsement. ASCO staff reviewed the CCO guideline for methodologic rigor, and an ASCO panel of content experts reviewed the content of the recommendations. For making decisions regarding adjuvant therapy, nodal status, tumor size, estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2) status, tumor grade, and lymphovascular invasion are relevant; Oncotype DX score and Adjuvant! Online may be used as risk stratification tools; and age, menopausal status, and medical comorbidities should be considered. Chemotherapy should be considered for patients with positive lymph nodes, ER-negative disease, HER2-positive disease, Adjuvant! Online mortality greater than 10%, grade 3 lymph node-negative tumors (T > 5 mm), triple-negative (ER-negative, PgR-negative, HER2-negative) tumors, lymphovascular invasion positivity, or estimated distant relapse risk of greater than 15% at 10 years based on Oncotype DX recurrence score (RS). Chemotherapy may not be beneficial or required for small node-negative tumors (T < 5 mm) without high-risk features or for patients with HER2-negative, strongly ER-positive, and PgR-positive cancer with micrometastatic nodal disease, T less than 5 mm, or Oncotype DX RS with an estimated distant relapse risk of less than 15% at 10 years. The ASCO panel endorses the recommendations with minor suggested revisions and highlights three areas that warrant further consideration: tumor histology and adjuvant therapy recommendations, risk stratification tools and proposed Oncotype DX RS thresholds to guide decisions about chemotherapy, and patient factors in decision making.