A Rare Metastatic Primary Rectal Melanoma in a Geriatric Male

Abstract

Primary rectal melanoma (PRM) is an uncommon malignancy whose etiology remains unknown. Most patients present with rectal bleeding. Distant metastasis is commonly seen in the lung and liver. The incidence rates for locoregional lymph node metastases on initial presentation are almost 60%. Histology and immunochemistry are useful and are the gold standard for diagnosis. The prognosis is very poor due to the late presentation of patients. Optimum surgical treatment remains controversial. Abdominoperineal resection was considered traditionally but over time, has been found to have no survival benefit. Current literature and studies, therefore, recommend wide local excision. The beneficial effects of chemotherapy versus radiotherapy use are still debatable. Herein, we discuss a case of a 72-year-old Caucasian male with rectal bleeding found to have metastasized PRM.

J Med Cases. 2022;13(8):369-373
doi: https://doi.org/10.14740/jmc3929