[A case of anorectal melanoma localized in mucosa]

The patient was a 67-year-old woman. An elevated rectal lesion had been identified at a local clinic, and colonoscopy revealed a 7-mm black elevated lesion with blackening of the surrounding mucosa. Malignant melanoma was diagnosed by biopsy, and the patient was referred to our department. An invasion depth of M was diagnosed on the basis of preoperative imaging. Local excision was considered, but abdominoperineal resection was performed in light of its nature, to perform curative resection. Pathological findings showed abnormal cells staining positive for HMB-45 in the tumor and surrounding mucosa, but these were localized within the mucosa. As of 1 year and 6 months after surgery, the patient has survived without recurrence.