A comparative study of the clinical characteristics and outcomes of HR-positive HER2-negative breast cancer patients over and under 65 years old

Purpose The purpose of this study was to compare the clinical characteristics and outcomes of hormone receptor-positive (HR+) human epidermal growth factor 2-negative (HER2−) breast cancer among elderly patients (over 65 years old) and younger patients. Methods This was a retrospective cohort study of 328 patients who were treated for breast cancer at Pusan National University Yangsan Hospital between January 2009 and December 2014. Tumor characteristics, surgical methods, and survival outcomes were compared between the two age groups (