Omission of sentinel lymph node biopsy in elderly patients with HR+ /HER2 − breast cancer: A population-based analysis from Taiwan

Abstract The study evaluated whether omission of sentinel lymph node biopsy (SLNB) affects survival outcomes in elderly patients (≥70 years) with hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative, node-negative breast cancer. We hypothesized that omission of SLNB does not compromise cancer-specific survival in this population. We utilized data from the Taiwan Cancer Registry (TCR). From 2011 to 2020, we identified 5,743 eligible HR+/HER2-, cN0 breast cancer cases in patients aged > 70 years. A total of 28.6% (n=1,642) underwent surgery without a SLNB. Of those with a positive SLNB result (n=805), 27% (n=218) were treated without further axillary lymph node dissection (ALND). In the multivariate analysis for patients aged > 80 years, performing a SLNB did not significantly impact either cancer-specific survival (CSS) or overall survival (OS). Taking hormone therapy only as the baseline risk, the adjusted hazard ratio (aHR) for SLNB use versus no use was 1.03 for CSS and 1.18 for OS. Propensity score-matched CSS also supported the safe omission of SLNB for patients aged > 80 years. For SLNB-negative cases, no significant difference in survival was found among the treatment combinations (endocrine alone and combinations of endocrine with surgery, radiotherapy, or chemotherapy). For SLNB-positive patients, the combination of hormone, chemo-, and radiotherapy was required to achieve CSS comparable to SLNB-negative patients. Omitting SLNB for patients aged 80 or older with clinically node-negative breast cancer is safe, confirming the potential for de-escalation of axillary surgery in this population.