Utilizing propensity score matching methodology to assess the impact of adjuvant radiotherapy on the prognosis of men diagnosed with breast cancer

Background: Male breast cancer (MBC) is a rare condition, and the effectiveness of radiotherapy in treating MBC patients remains uncertain. This study aimed to investigate the role of adjuvant radiotherapy (RT) in the management of MBC. Methods MBC patients from the Surveillance Epidemiology and End Results (SEER) database were included in the study and were divided into RT and no-RT groups. A 1:1 propensity score matching (PSM) method was employed to balance baseline characteristics. Kaplan-Meier curves were used to evaluate the impact of RT on overall survival (OS) and breast cancer-specific survival (BCSS). Cox analyses were conducted to identify factors associated with survival. Subgroup analysis was performed to identify subgroups of MBC patients who might benefit from RT. Results In the matched cohort, the 5-year OS and BCSS rates were higher in the RT group compared to the no-RT group (p = 0.023, p = 0.035). Univariate and multivariate analysis demonstrated significant differences in both OS and BCSS associated with RT (p = 0.024, p = 0.037, p = 0.025, p = 0.028). Forest plots revealed a greater OS benefit in patients with T1 stage, age ≥ 60 years, estrogen receptor positivity (ER+), absence of distant metastasis (M0), married status, and with local or regional metastases. Furthermore, a greater BCSS benefit was observed in patients aged ≥ 60 years, ER+, progesterone receptor negativity (PR-), M0, married status, and with regional metastases who received RT for MBC. Conclusion RT in MBC patients is associated with improved survival and is recommended for patients aged ≥ 60 years with ER+, PR-, M0, married status, and regional metastases.