Primary rectal melanoma

Primary rectal melanoma is rare and only represents up to 4% of anorectal malignancies. The prognosis of such a diagnosis is significantly different to a metastatic melanoma deposit in the anorectal area and therefore differentiation between the two is of the utmost importance with regards to initial treatment and long-term management. Various immunohistochemical markers have been shown to be associated with primary melanoma and strongly aid in diagnosis. Surgical management is still widely disputed and multiple papers have been published comparing wide local excision with abdominoperineal resection. Here a case of primary rectal melanoma is presented with a brief discussion exploring diagnostic techniques, treatment options and prognostic factors.