Prevalence and predictors of adjuvant chemotherapy use after neoadjuvant endocrine therapy for HR-positive breast cancer

Neoadjuvant endocrine therapy facilitates clinical response and breast conservation in hormone receptor-positive breast cancer. Patient selection for adjuvant chemotherapy after neoadjuvant endocrine therapy is unclear and potentially evolving with use of genomic assays. Analysis of the National Cancer Database found that after neoadjuvant endocrine therapy for cT2-3N0-3M0 HR-positive HER2-negative breast cancer, a minority of the patients (20.4%) received adjuvant chemotherapy. This decision appeared to be driven by younger age, 21-gene recurrence score, and pathological nodal status.