Abstract
A 65-year-old woman underwent a low anterior resection due to rectal cancer. During follow-up, lung metastasis appeared, then partial thoracoscope-assisted lung resection was performed. During surgery, pigmentation of the left nipple was pointed out. Malignant melanoma was suspected from imprint cytology performed after surgery. Modified radical mastectomy and axillary dissection were performed. Immunohistochemical staining showed positive HMB45, so the histological diagnosis was malignant melanoma. No metastases were seen in the dissected axillary lymph nodes. Adjuvant chemotherapy with oral use of UFT/LV was performed to prevent a recurrence of rectal cancer. Two years after surgery, there has been no recurrence. Malignant melanoma originating on the nipple is extremely rare, and there have been only 3 cases, reported in the literature in Japan to date.
