Surgical Management of the Axilla in HR+/HER2- Breast Cancer in the Z1071 Era: A Propensity Score-Matched Analysis of the National Cancer Database.

Background: Axillary management varies between sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) for patients with clinical N1 (cN1), hormone receptor-positive (HR+), human epidermal growth factor receptor 2 (HER2)/neu-negative (HER2-), infiltrative ductal carcinoma (IDC) who achieve a complete clinical response (cCR) to neoadjuvant systemic therapy (NAST). This study sought to evaluate clinical practice patterns and survival outcomes of SLNB versus ALND in this patient subset.

Methods: Patients with cN1, HR+/HER2-, unilateral IDC demonstrating a cCR to NAST were identified from the 2012-2017 National Cancer Database (NCDB) and stratified based on final axillary surgery management (SLNB vs ALND).