Survival outcomes of omitting surgical axillary staging in male early breast cancer: a propensity score-matched SEER analysis

Abstract Background While recent trials have demonstrated the safe omission of axillary surgery in selected female breast cancer patients, its applicability in men remains unclear. This study aimed to evaluate the survival impact of omitting surgical axillary staging in men with early breast cancer. Methods Using the Surveillance, Epidemiology, and End Results database, we identified male patients diagnosed with T1 or T2 breast cancer between 2000 and 2019 who underwent breast surgery. Patients were classified into surgical axillary staging (sentinel lymph node biopsy or axillary lymph node dissection) and non-staging (no lymph node examined) groups. Propensity score matching (PSM) was used to eliminate bias between groups. Overall survival (OS) and breast cancer-specific survival (BCSS) were compared between groups using Kaplan-Meier and Cox regression analyses. Results Among 3,581 eligible male patients, 214 (6.0%) did not undergo surgical axillary staging. After PSM, 711 patients (non-staging: 166; staging: 545) were effectively balanced across all baseline characteristics (all P > 0.05). Surgical axillary staging was independently associated with significantly improved OS (hazard ratio [HR] = 0.493, P < 0.001) and BCSS (HR = 0.370, P < 0.001). In stratified analysis, staging provided no significant improvement in OS for patients with tumor size ≤ 1 cm (HR = 0.584, P = 0.241). Omitting surgical axillary staging did not significantly compromise BCSS in patients aged 65–79 years, with Grade I–II tumors, with tumor size ≤ 1 cm, or receiving radiotherapy (all P > 0.05). Conclusions Surgical axillary staging is significantly associated with better OS and BCSS in early male breast cancer. Nonetheless, male patients aged 65–79 years who present with HR+/HER2–, Grade I–II, T ≤ 1 cm breast cancer planning for radiotherapy may represent a potential low-risk cohort for future prospective trials investigating axillary surgical omission.