As reported in the Journal of Clinical Oncology by Louis Fehrenbacher, MD, and colleagues, the phase III NSABP B-47/NRG Oncology trial has shown no invasive disease–free survival benefit with the addition of trastuzumab to adjuvant chemotherapy therapy in patients with HER2-negative breast cancer determined by fluorescence in situ hybridization ratio and an immunohistochemistry score of 1+ or 2+.

As reported in the Journal of Clinical Oncology by Ambrosone et al, an analysis of the SWOG S0221 trial population suggests that use of antioxidant and nonantioxidant dietary supplements, but not multivitamins, before and during adjuvant chemotherapy may be associated with poorer treatment outcomes in patients with high-risk early breast cancer.

As reported in The Lancet by Frank A. Vicini, MD, and colleagues, 10-year follow-up in the phase III NSABP B-39/RTOG 0413 equivalence trial has shown that accelerated partial-breast irradiation did not achieve equivalence to whole-breast irradiation in preventing local recurrence in women receiving breast-conserving therapy for early breast cancer.

In a U.S. Food and Drug Administration (FDA) pooled analysis reported in The Lancet Oncology, Jennifer J. Gao, MD, and colleagues found that the magnitude of progression-free survival benefit with the addition of a cyclin-dependent kinase (CDK) 4/6 inhibitor to endocrine therapy in women with advanced or metastatic hormone receptor–positive, HER2-negative breast cancer was similar across examined subgroups.

As reported in The New England Journal of Medicine by Dennis J. Slamon, MD, PhD, and colleagues, in the phase III MONALEESA-3 trial, the second interim analysis of overall survival has shown a significant benefit with the addition of ribociclib to fulvestrant in first- or second-line treatment of postmenopausal patients with hormone receptor–positive, HER2-negative advanced breast cancer.