Peritoneal Carcinomatosis From Malignant Melanoma After Wide Local Excision of a T1a Lesion: A Case Report

Cutaneous melanoma is an aggressive skin cancer with a high propensity for distant metastasis. Peritoneal metastasis from cutaneous malignant melanoma is extremely rare and associated with a low five-year overall survival rate. This report reviews a case of a 78-year-old man with peritoneal carcinomatosis after a wide local excision of a T1a invasive malignant melanoma of the scalp 10 months prior. Although rare, patients with a recent history of melanoma who present with obscure or odd symptoms should be worked up for metastatic disease by their surgeon or medical oncologist. Carcinomatosis can develop, and early treatment with immunotherapy has been shown to improve five-year overall survival and progression-free survival in patients with advanced melanoma.