Development of malignant melanoma after levodopa therapy for Parkinson's disease. Report of a case and review of the literature.

Malignant melanoma developed in an apparently benign nevus four months after therapy with levodopa in a patient with Parkinson's disease. This case is reported, and previous reports of this possible causal relationship are reviewed. Although this and previously reported cases are not inconsistent with the unpredictable and variable natural history of malignant melanoma, it seems prudent to clinically monitor pigmentary lesions in patients receiving levodopa therapy. Biopsy specimens of suspicious lesions in these patients should be examined histologically, and if malignancy is found, alternate therapies for treatment of parkinsonism should be considered.