Male breast cancer: A multicenter study in Aragon over 27 years.

Introduction: Male breast cancer accounts for 1% of all breast cancers. Its low frequency leads to a lack of awareness, resulting in significant diagnostic delays. Additionally, this limits the available evidence, which primarily uses diagnostic-therapeutic algorithms based on women.

Objectives: To analyze the prevalence, clinical presentation, anatomical and pathological characteristics, and prognosis of male breast cancer using one of the largest series available. Secondarily, to compare our data with studies conducted in women.

Materials and methods: A multicenter, observational, descriptive, retrospective study was conducted in the autonomous community of Aragon, Spain, from 1995 to 2022 including men with a pathological diagnosis of breast cancer.

Results: A total of 148 patients were included, with a prevalence of 1%. The most common clinical presentation was a palpable retroareolar mass. Invasive ductal carcinoma was the most frequent type (88.89%), and luminal B was the predominant subtype (47.76%). Surgery was the most utilized treatment; mastectomy was performed in 90.34% and AL in 46.89%. At diagnosis, 52.46% had extramammary involvement. The recurrence rate was 24.1%, and the mortality attributed to the disease was 14.6%.

Conclusions: There is a high rate of metastatic involvement at diagnosis, a high percentage of mutilating surgeries, and a high number of recurrences compared to available studies on males. Additionally, a worse prognosis is observed compared to breast cancer in women, despite these tumors having a less aggressive molecular subtype. These findings highlight the importance of conducting studies focused on men to develop specific protocols.