Selection of optimal adjuvant chemotherapy and targeted therapy for early breast cancer: ASCO clinical practice guideline focused update

Purpose To update key recommendations of the ASCO guideline adaptation of the Cancer Care Ontario guideline on the selection of optimal adjuvant chemotherapy regimens for early breast cancer and adjuvant targeted therapy for breast cancer. Methods An Expert Panel conducted targeted systematic literature reviews guided by a signals approach to identify new, potentially practice-changing data that might translate to revised practice recommendations. Results The Expert Panel reviewed phase III trials that evaluated adjuvant capecitabine after completion of standard preoperative anthracycline- and taxane-based combination chemotherapy by patients with early-stage breast cancer HER2-negative breast cancer with residual invasive disease at surgery; the addition of 1 year of adjuvant pertuzumab to combination chemotherapy and trastuzumab for patients with early-stage, HER2-positive breast cancer; and the use of neratinib as extended adjuvant therapy for patients after combination chemotherapy and trastuzumab-based adjuvant therapy with early-stage, HER2-positive breast cancer. Recommendations Patients with early-stage HER2-negative breast cancer with pathologic, invasive residual disease at surgery following standard anthracycline- and taxane-based preoperative therapy may be offered up to six to eight cycles of adjuvant capecitabine. Clinicians may add 1 year of adjuvant pertuzumab to trastuzumab-based combination chemotherapy in patients with high-risk, early-stage, HER2-positive breast cancer. Clinicians may use extended adjuvant therapy with neratinib to follow trastuzumab in patients with early-stage, HER2-positive breast cancer. Neratinib causes substantial diarrhea, and diarrhea prophylaxis must be used.