New approaches in the management of male breast cancer

Male breast cancer (MBC) is a rare condition that accounts for 0.1% of all male cancers. Our current evidence base for treatment is derived from female breast cancer (FBC) patients. Risk factors for MBC include age, genetic predisposition, race, sex hormone exposure, and environmental factors. Most patients present later and with more advanced disease than comparable FBC patients. Tumors are likely to be estrogen receptor and progesterone receptor positive, with the most common histologic type being invasive ductal carcinoma. Triple assessment remains the criterion standard for diagnosis. Primary MBC is mostly managed initially by simple mastectomy, with the option of breast conserving surgery, which carries an increased risk of recurrence. Sentinel node biopsy is recommended as the initial procedure for staging the axilla. Reconstructive surgery focuses on achieving primary skin closure, and radiotherapy largely follows treatment protocols validated in FBC. We recommend chemotherapy for men with more advanced disease, in particular, those with estrogen receptor negative histology. MBC responds well to endocrine therapy, although it is associated with significant adverse effects. Third-generation aromatase inhibitors are promising but raise concerns due to their failure to prevent estrogen synthesis in the testes. Fulvestrant remains unproven as a therapy, and data on trastuzumab is equivocal with HER2 receptor expression and functionality unclear in MBC. In metastatic disease, drug-based hormonal manipulation remains a first-line therapy, followed by systemic chemotherapy for hormone-refractory disease. Prognosis for MBC has improved over the past 30 years, with survival affected by disease staging, histologic classification, and comorbidity.