Primary Anorectal Malignant Melanoma Successfully Treated with Local Excision and Immunochemotherapy-A Case Report

• Published in: Nippon Shokaki Geka Gakkai zasshi Vol. 37; no. 11; pp. 1787 - 1793
• Main Authors: Tsuchida, Kazuhito, Yoneyama, Katsuya, Sasaki, Kazuyoshi, Jin, Yasuyuki, Kasahara, Akio, Kabara, Takeshi, Iwasaki, Hiroyuki, Kosuge, Takayuki, Rino, Yasushi, Nagashima, Yoji
• Format: Journal Article
• Language: Japanese
• Published: The Japanese Society of Gastroenterological Surgery 2004
• Subjects: anorectal malignant melanoma; long time survival; therapeutic regimen
• ISSN: 0386-9768; 1348-9372
• DOI: 10.5833/jjgs.37.1787

Anorectal malignant melanoma is rare, has no established therapeutic regimen, and suggests a generally un-favorable prognosis. We report such a case treated successfully with local resection followed by chemother-apy and immunotherapy. A 65-year-old woman with anal bleeding was found on physical examination to have two pedunculated black polyps at 8°on the wall of the anorectum, histologically diagnosed as malignant mela-noma after transanal polypectomy. The tumors were a maximally 7mm thick and invasion was limited to the submucosa. Tumor cells apparently involved the cut margin in spite the absence of nodal and visceral metas-tasis. After chemotherapy and immunotherapy, follow-up biopsy showed residual melanoma cells around the polypectomy stump. Despite additional wide local excision, histological examination failed to reveal residual malignant melanoma cells. After surgery, we conducted immunochemotherapy again and the woman remains well without any sign of recurrence in the more than 6 years following surgery. This successfully case of anorectal melanoma provides valuable information on establishing an effective therapeutic regimen for this disease.