Melanoma is the most common tumor to metastasize to the gastrointestinal (GI) tract. 60% of patients who die with malignant melanoma have GI involvement at autopsy1. Symptomatic disease presenting during life is unusual. Anorectal melanoma, a rare tumor that represents 1% of all melanomas and less than 4% of all anal malignancies, manifests with a range of non-specific symptoms and physical exam findings2. In fact, about one-third of lesions may be amelanotic3,4. Initial misdiagnosis as a benign lesion such as hemorrhoid is common.
We report 3 cases of anorectal melanoma presenting as primary GI complaints all without known cutaneous malignancy. Physicians must be aware of the clinical spectrum, anatomic distribution, and diagnostic difficulties associated with anorectal melanoma.
Zhang, MD, Jinyu; Sochat, MD, Matthew; and Feller, MD, Edward R.
"Anorectal Melanomas: Case Series,"
The Medicine Forum: Vol. 17
, Article 9.
Available at: http://jdc.jefferson.edu/tmf/vol17/iss1/9