Clinicopathological characteristics and survival outcomes of male breast cancer according to race: A SEER population-based study

// He-Fen Sun 1, 2 , Yang Zhao 1, 2 , Shui-Ping Gao 1, 2 , Liang-Dong Li 1, 2 , Wen-Yan Fu 1, 2 , Hong-lin Jiang 3 , Meng-Ting Chen 1, 2 , Li-Peng Yang 4 and Wei Jin 1, 2 1 Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Collaborative Innovation Center of Cancer Medicine, Fudan University Shanghai Cancer Center, Shanghai, 200030, China 2 Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200030, China 3 Division of Molecular Medicine and Genetic, Department of Internal Medicine and Life Sciences Insititute, University of Michigan, Ann Abor, Michgan 48109, USA 4 Department of pathology, School of Basic Medical Sciences, Fudan University, Shanghai, 200030, China Correspondence to: Wei Jin, email: jinwei7207@163.com Keywords: male breast cancer, race, overall survival, SEER Received: December 30, 2016      Accepted: May 15, 2017      Published: May 26, 2017 ABSTRACT To investigate the clinicopathological characteristics and survival outcomes of breast cancer in the male population, 8,607 cases of patients were identified in the Surveillance, Epidemiology, and End Results (SEER) database, including white males ( n = 7122), black males ( n = 1111), and other males (American Indian/AK Native, Asian/Pacific Islander) ( n = 374). Black male breast cancer patients were more likely to be in stages II–IV and have more advanced tumors. The rate of lymph node (LN) involvement at diagnosis was higher in black men than in whites and others. The ER- and PR-positive rates were lower in black men than in whites and others. The distant metastasis rate was higher in blacks than in whites and others. Furthermore, the overall survival (OR) rates and breast cancer-specific survival rates were significantly poorer in blacks than in whites and others (χ 2 = 29.974, P < 0.001; χ 2 = 7.285, P = 0.026, respectively). In a multivariate analysis, the results showed that race could also be a prognostic indicator ( P < 0.001). Moreover, significant differences were also observed in OS among 1:1:1 matched white, black, and other groups ( P < 0.001). Differences in outcomes may be partially explained by differences in tumor grades, LN status, and ER and PR status between the 3 groups. This study might provide insights into a better understanding of male breast cancer.