[A Case of Sentinel Lymph Node Biopsy for Breast Cancer in an Elderly Man].

A 75-year-old man noted an elastic hard tumor under his left areola.Mammography showed a microlobulated mass, so he was diagnosed with category Ⅳ breast cancer.Ultrasonography showed a circular hypo-echoic mass that was 21mm in diameter with a moderately indistinct border.Based on core needle biopsy, the tumor was diagnosed as invasive ductal carcinoma.We performed a whole-body check-up, and he was diagnosed with T1N0M0, StageⅠ breast cancer.The patient underwent mastectomy and sentinel lymph node biopsy.The pathological diagnosis based on the resected surgical specimen was invasive ductal carcinoma, positive for ER and negative for PgR and HER2/neu protein expression, and the Ki-67 positive cell index was 20%.The surgical margins were negative, and there was no metastasis in the sentinel lymph nodes.He was administered endocrine therapy as adjuvant therapy.Two years after the surgery, he remains well without metastases.