Objective: To comprehensively describe the tumor and clinical characteristics of breast cancer in a cohort of male patients and to assess the factors that affect survival.
Background: Much of the standard care of male breast cancer is based on the diagnosis and treatment strategies of female breast cancer. However, important clinical differences between the two have been elucidated, which suggests the need for unique attention to male breast cancer.
Methods: We evaluated the records of male patients who were diagnosed with breast cancer between 2004 and 2015 using the National Cancer Database (NCDB). Data obtained were demographic characteristics, clinical and tumor data, type of therapy, as well as survival data. We used descriptive statistics to characterize our study population. We then performed a survival and Cox proportional hazards analysis.
Results: We identified 16,498 patients (median age: 63 years). Several treatment modalities were used, of which surgery was the most common (14,882 [90.4%]). The total follow-up time was 13 years (156 months). Five-year survival was 77.7% (95% CI 76.9-78.4) and 10-year survival was 60.7%. In a Cox proportional hazards model, mastectomy was associated with the greatest survival (hazard ratio [HR] 0.49; p < 0.001).
Conclusion: We report what is to our knowledge the largest national population-based cohort of male breast cancer patients. Importantly, our data suggests that similar to female patients, several treatment modalities are significantly associated with improved survival in male patients, particularly surgery. Increasing age, black race, government insurance, more comorbidities, and higher tumor stages are associated with decreased survival.
Keywords: Chemotherapy; Male breast cancer; Mastectomy; Proportional hazards analysis; Radiotherapy; Survival analysis.