Breast cancer in men in the United States: a population-based study of diagnosis, treatment, and survival

Abstract

Background: Breast cancer in men is rare, so clinical trials are not practical. Recommendations suggest treating men who are diagnosed with breast cancer using the guidelines for postmenopausal women; however, to date, no population-based studies have evaluated patterns of care.

Methods: To examine characteristics, treatment, and survival among men with newly diagnosed breast cancer, in 2003 and 2004, 512 men were identified from the Surveillance, Epidemiology and End Results Program. Data were reabstracted and therapy was verified through the patients' treating physicians.

Results: The majority of men (79%) were diagnosed through discovery of a breast lump or other signs/symptoms. Among men who had invasive disease, 86% underwent mastectomy, 37% received chemotherapy, and 58% received hormone therapy. In multivariate analysis, tumor size (P=.01) and positive lymph node status (P<.0001) were associated positively with the use of chemotherapy, whereas age group (P<.0001) and current unmarried status (P=.01) had negative associations. Among men who had invasive, estrogen receptor (ER)-positive/borderline tumors, the use of tamoxifen or aromatase inhibitors (AIs) was associated with age group (P=.05). Among men who had invasive disease, cancer mortality was associated with tumor size (P<.0001). Among men with ER-positive/borderline disease, increased cancer mortality was associated with tumor size (P<.0001), current unmarried status (P=.04), and decreased mortality with tamoxifen (P=.04).

Conclusions: Tumor characteristics and marital status were the primary predictors of therapy and cancer mortality among men with breast cancer. Although AIs are not currently recommended, they are commonly prescribed. However, their use did not result in a decrease in cancer mortality. Research must examine the efficacy of AIs with and without gonadotropin-releasing hormone analogues.