Abstract: Objective To review the clinical feature, current treatment, and genetic etiology of Chinese male breast cancer (MBC) patients through MBC case series. Methods This article reviewed the demographic characteristics, clinical and pathological features, treatment and follow-up outcomes of 50 MBC patients who were hospitalized in two cancer hospitals in Beijing from 2015 to 2019. Furthermore, the panel-based next-generation sequencing was performed on 25 of the MBC patients to identify the genetic etiology. Results In this study, the average age at onset of MBC patients was 58.26±11.54 years. Overweight and obesity patients accounted for 60.00%. Most MBC patients were androgen-receptor-positive (95.24%) and estrogen-receptor-positive(89.36%),while the proportion of triple-negative breast cancer (10.64%) was higher than that found in Caucasians. However, the ratio of breast-conserving surgery (6.12%) and sentinel lymph node biopsy (26.53%) was relatively low. Although endocrine therapy (84.00%) played an important role in most MBC patients' adjuvant therapy, adjuvant radiotherapy (20.00%) and chemotherapy (52.00%) is inadequate. Furthermore, two patients (8.00%) receiving the genetic test had pathogenic mutations BRCA1/2 genes. Conclusions The clinical characteristics and genetic etiology of Chinese MBC patients have shown significant specificities which suggests that for Chinese MBC patients less surgical operation and more adjuvant radiotherapy as well as chemotherapy seems to be a smart choice.

Key words: male breast cancer, clinical features, pathological features, BRCA1/2