Unilateral nipple discharge in a man without a palpable mass diagnosed as breast cancer

A 69-year-old man without a family history of breast cancer presented to his primary care physician with a 1-year history of clear, unilateral nipple discharge (ND) without an associated palpable breast mass. His laboratory findings were significant for hyperprolactinaemia at 28 ng/mL. Diagnostic work up including mammography, ultrasound and core needle biopsy ultimately revealed a ductal carcinoma in situ and a rare papillary variant of invasive ductal carcinoma. The patient was referred to a multidisciplinary oncology team and underwent a right total mastectomy followed by adjuvant hormonal therapy. The patient made a good postoperative recovery and remains without evidence of recurrence 6 months from surgery. Male breast cancer is rare, but its incidence is increasing. Male breast cancer presenting as ND without a palpable mass is uncommon. Early recognition of breast symptoms in men can lead to earlier diagnoses and improved outcomes.