Surgical treatment for anorectal malignant melanoma: report of five cases and review of 79 Japanese cases

Introduction Anorectal malignant melanoma (AMM) is a relatively rare disease. Because of its poor prognosis, the optimal surgical treatment for AMM is still controversial and difficult to determine. In this paper, we report five cases of AMM that have been treated by surgery and/or other methods at Shinshu University Hospital within the last decade. We also review the present five cases along with 74 other Japanese cases reported between 1997...