Co-occurrence of Malignant Melanoma and Squamous Cell Carcinoma on Burn Scars: A Case Report.

Tumors arising from burn scars are not rare but sometimes cause the rare co-existence of different tumors. However, detailed information on this topic remains largely unknown. We present a case of the co-occurrence of malignant melanoma and squamous cell carcinoma in a patient with a history of burn scars. A 73-year-old man presented with an erythematous plaque on his left lower leg that gradually turned into a tumor with ulceration. He also presented with scaly tumors at other sites within the same burn scar lesion. He had a history of burns on the left leg at the age of 20 years. After surgical resection of the tumors, histological analysis revealed that the posterior aspect of the largest tumor was malignant melanoma, and the remaining two tumors were squamous cell carcinomas, indicating the co-existence of different types of malignant skin cancers. Based on a literature review of previously published case reports, this is the first report to highlight the importance of complete skin grafts in reducing this risk.