Successful treatment of accessory breast cancer with endocrine therapy.

Accessory breast cancers in males are extremely rare, and only a few cases have been reported in the literature. In this paper, an 87-year-old male patient was diagnosed with an accessory breast cancer by means of computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT), and immunohistochemistry based on needle biopsy, and has undergone successful resection and postoperative adjuvant endocrine therapy. He was the oldest male patient with an accessory breast cancer reported in the Chinese Hospital Knowledge Database and PubMed literature from 1975 to 2015.