Abstract
SUMMARY: BACKGROUND: The aim of this study was to investigate the clinicopathologic features of male breast cancer. CASE REPORT: We present the clinicopathologic data of a 72-year-old male patient with occult breast cancer, who was diagnosed and underwent surgery in our hospital. The diagnosis was confirmed by histological examination, and the patient underwent modified radical mastectomy and axillary dissection. The histological examination showed no tumor foci in the resected breast tissue, but 2 of 15 dissected axillary lymph nodes were invaded by infiltrating ductal carcinoma. Immunohistochemistry staining was negative for both estrogen and progesterone receptors, but showed expression of p53 protein (+++), proliferating cell nuclear antigen (PCNA) (+++), Bcl-2 on-coprotein (+++), nm23 protein (++), multidrug resistance protein (MRP) (++), and human epidermal receptor (HER-2) oncoprotein (+++). 24 months after being diagnosed, the patient is alive without any residual or metastatic disease. CONCLUSIONS: Breast cancer is very rare in men, and the occurrence of occult breast cancer is even less common. Axillary metastases can present as the first manifestation of breast cancer in a male.