No abstract

Male breast cancer (BC) comprises less than 1% of all BCs. Family history of BC and the presence of genetic mutation are the main risk factors. Our objective is to estimate the prevalence of familial cancer aggregation and genetic mutations in a series of cases of male BCs. We studied a series of male BC patients from the health area of Vigo diagnosed between October 1997 and December 2020. 72 men with primary BC were included. The mean age of all male BCs was 69.0 years, similar to those of hereditary BCs (66.2). We observed a high frequency of bilaterality (4%). We highlight the underuse of genetic testing: only in 14 men (19.4%). The most frequently detected pathogenic mutation (n = 5: 7%) was in the BRCA2 gene, and 3 of them presented the same type of mutation (c.9382C> T (p.Arg3128Ter) in exon 25). We also detected a pathogenic mutation in the BRCA1 gene and the MUTYH gene. 34.6% of male BCs that were not genetically studied had an intense familial aggregation of cancer that was compatible with a hereditary cancer syndrome. 33.3% men had at least one other malignant neoplasm in addition to their BC, with prostate adenocarcinoma being the most frequent associated neoplasia (n = 8). Up to 15.3% were diagnosed with 3 or more malignant neoplasms. It is necessary to increase the genetic testing in male BC in order to o identify hereditary BC and offer the pertinent preventive measures to them and their families.