[Anorectal Malignant Melanoma Is a Very Rare Disease and Has a Poor Prognosis]

We performed abdomino-perineal-resection(APR)on 2 cases of anorectal malignant melanoma. The first case was a 70- year-old woman suffering from bloody stool. Colonoscopy showed a black tumor in the rectum. Biopsy revealed a malignant melanoma. A CT scan showed multiple lung metastases and liver metastasis. She underwent surgery for the purpose of bleeding control, but died shortly thereafter because her liver and lung metastases had worsened. The second case was a 43- years-old man suffering from bloody stool. He had a black type 3 tumor in the rectum. A biopsy revealed malignant melanoma. A CT scan showed lateral lymph node swelling. He underwent APR with right side-lateral dissection. An established treatment for anorectal malignant melanoma has not been agreed upon and it is controversial. We experienced 2 cases that underwent surgery and we report them along with relevant information from the literature.