In a recent literature review, researchers from University of Minnesota Medical School in Minneapolis found a link between Parkinson’s disease and melanoma, with possible causes including family history and genetic predisposition. The review was published in the journal Dermatologic Surgery and titled “A Review of the Association Between Parkinson Disease and Malignant Melanoma.”
Since the 1970s and with the initiation of levodopa (L-DOPA) treatments for patients with Parkinson disease (PD), scientific literature has suggested a possible association between PD and melanoma. A number of past observations from case reports implicated levodopa use in PD patients as a risk factor for melanoma. Biologically, both diseases share the dopamine biochemical pathway, and an association is also plausible as exogenous levodopa may stimulate melanogenesis, leading to an accumulation of melanin and, hence, melanoma growth.
Max Disse and his colleagues explored the published evidence regarding possible causal links between PD and melanoma. The search was performed using PubMed and Google Scholar, and the researchers used terms that included “Parkinson’s disease, Parkinson’s, melanoma, melanoma + Parkinson’s disease, alpha-synuclein and melanoma.”
After analyses, the authors determined that patients with PD have an overall 27 percent decreased risk of cancer diagnoses. However, melanoma and breast cancer were found to have an unusually high rate of co-occurrence with PD.
The researchers also identified a link between a family history of melanoma, lighter hair and skin color, and a higher risk for PD. In addition, having a first-degree relative with either PD or melanoma was found to increase the risk of developing the other disease. Other possible associations identified included pigmentation genes in neural-derived cells, MC1R polymorphisms, abnormal cellular autophagy, and pesticides.
“Both PD and melanoma are likely multifactorial diseases including genetic and environmental risk factors, and further research will be needed to completely evaluate this link,” the researchers concluded, according to a recent news release. “It is prudent that dermatologists be aware of this increased risk of melanoma and explain this risk to their patients with PD and recommend them sun protection, self-surveillance and periodic skin check-up.”