Breast cancer in men is rare, so clinical trials are not practical. Recommendations suggest that men diagnosed with breast cancer be treated using guidelines for postmenopausal women, but there are no population-based studies to evaluate patterns of care.

To examine characteristics, treatment and survival in men newly diagnosed with breast cancer in 2003and 2004, 512 men were identified from the Surveillance, Epidemiology and End-Results program. Data were re-abstracted and therapy verified through the patients’ treating physicians.

The majority (79%) of men were diagnosed through discovery of a breast lump or other signs/symptoms. In men with invasive disease 86% were treated with mastectomy, 37% received chemotherapy, and 58% received hormonal therapy. In multivariate analysis, tumor size (p=0.01) and positive nodes (p <0.0001) were positively associated with the use of chemotherapy; age group (p <0.0001) and not currently married (p=0.01) were negatively associated. In men with invasive ER positive/borderline tumors, the use of tamoxifen or aromatase inhibitors was associated with age group (p=0.05). Among men with invasive disease, cancer mortality was associated with tumor size (p<0.0001). Among men with ER positive/borderline disease increased cancer mortality was associated with tumor size (p<0.0001), not currently married (p=0.04) and decreased mortality with tamoxifen (p=0.04).

Tumor characteristics and marital status were the primary predictors of therapy and cancer mortality. Although AIs are not currently recommended they are commonly prescribed. However, they did not result in a decrease in cancer mortality. Research must examine the efficacy of AI’s with and without GnRH analogues.