Surgical Management of Mucosal Melanoma of Anal Canal: A Rare Case Study

Abstract

Melanoma is the cancer of melanocytes. Mucosal melanoma is a rare and aggressive form of melanoma arising from unchecked proliferation of melanocytes in the mucosal membrane of non-sun exposed area of gastro-intestinal, respiratory or urogenital tracks. Ano-rectal melanoma accounts for 0.4% to 1.6% of all melanomas and less than 1% of ano-rectal malignant tumors. In this case, a 55 years old female patient presented to Shalya Tantra OPD of provincial Ayurveda hospital, Dang with the chief complaint of irreducible mass per rectum for 2.5 years. Upon local examination, a tri-lobulated black pedunculated mass was found just distal to ano-rectal junction. With the provisional diagnosis of mucosal melanoma and normal Carcinoembryogenic Antigen (CEA) value, the mass was transfixed and ligated. The patient recovered well following operation. Proctoscopic examination of 15^th post-operative day revealed healthy ano-rectal mucosa with no any evidence of disease recurrence. The mass was transfixed to firmly occlude the blood flow and secure the mass. The occluded blood supply cut off oxygen and nutrients to the mass causing pressure necrosis. The necrotic tissue eventually sloughed off leaving behind healthy healing surgical margins.