Background: Male breast cancer (MBC) is a rare disease with a rising incidence trend. The major risk factors related to MBC are a positive family history of breast cancer (BC) and BRCA1/2 mutations, which indicate a relevant genetic role. Methods: In this retrospective series, we enrolled 69 male patients presenting with male breast cancer (MBC) between 01/01/1992 and 31/12/2018, and 26 high-risk not-affected men presenting between 01/01/2016 and 31/12/2018. Participants' electronic clinical records were reviewed. Patients' data reported age at diagnosis, tumor characteristics, therapeutic management, and BRCA1/2 status as well as a family history of breast, ovarian, or prostate cancer (PCa) in first-degree relatives. Results: We analyzed 69 MBC patients. Median age was 64 years. The majority of tumors diagnosed were of an early TNM stage. The most frequent histological subtype was invasive ductal carcinoma (76.7%). Hormone receptors were positive in >90% of MBC cases. Nearly all patients underwent modified radical mastectomy or total mastectomy. Adjuvant endocrine therapy was delivered in 59.4%. Among MBC-affected patients, we recorded a high percentage of a positive family history of BC. Mutational analysis for the BRCA1/2 genes was performed in 17 MBC patients; 11.8% were carriers of BRCA2 pathogenic mutations. Among 26 healthy high-risk subjects included in this case series, 4 were BRCA1 mutation carriers and 9 were BRCA2 mutation carriers. Discussion: We evaluated the distribution of clinicopathological characteristics in MBC subjects and assessed the frequency of mutations in the BRCA genes in affected patients and healthy high-risk subjects, with the aim of proposing a surveillance program for BC and PCa
