ABSTRACT
BACKGROUND: An association between melanoma and Parkinson disease (PD) has been hinted at in the neurology and oncology literature since the 1970s after the initiation of levodopa (L-DOPA) therapy for PD. Given that L-DOPA is a substrate in melanin synthesis, there existed a concern that this therapy might cause melanoma. OBJECTIVE: The objective was to research possible etiological links to explain the connection between PD and melanoma. METHODS: A PubMed and Google Scholar literature search was performed using access provided by the University of Minnesota biomedical library. RESULTS: Patients with PD have an overall decreased risk of cancer diagnoses. However, breast cancer and melanoma have an uncharacteristically high rate of co-occurrence with PD. Family history of melanoma and lighter hair and skin color confer a higher risk of developing PD, and having a first-degree relative with either disease conveys a significantly increased risk of developing the other. Other possible connections that have been explored include pigmentation genes in neural-derived cells, pesticides, MC1R polymorphisms, and abnormal cellular autophagy. CONCLUSION: Although a link between PD and melanoma exists, the etiology of this link continues to be elusive. Both PD and melanoma are likely multifactorial diseases involving genetic and environmental risk factors.
