Table 4.

Studies investigating the association between melanoma and Parkinson’s disease.

Study	Study design	Main results
Olsen et al. (2005)	Retrospective, Cohort study, Danish cancer registry	Increased relative risks of melanoma and breast cancer in PD patients.
Olsen et al. (2006)	Retrospective, Case-control, National Danish Hospital Register	Increased prevalence of melanoma before the diagnosis of PD.
Baade et al. (2007)	Australian	Melanoma patients had a 3-fold increased risk of dying from PD.
Inzelberg and Israeli-Korn (2009)	Pubmed search of cohort studies	The increased risk of melanoma for PD patients cannot be attributed to L-dopa treatment.
Bertoni et al. (2010)	Prospective clinicopathological study, USA cohort.	Melanoma prevalence is higher in PD patients.
Liu et al. (2011)	Meta-analysis	Melanoma occurrence is higher after the diagnosis PD, but not before PD diagnosis.
Rugbjerg et al. (2012)	Cohort study, National Danish Hospital Register	Increased risks for malignant melanoma, nonmelanoma skin cancer and breast cancer in PD patients.
Kareus et al. (2012)	Cohort study, Population-based pedigree-linked study, Utah cancer registry	Risk association for melanoma in PD patients as well as increased risk for PD in relatives of individuals with melanoma. Association between PD and prostate cancer.
Wirdefeldt et al. (2014)	Cohort study, Swedish Multi-Generation Register	Melanoma risk is higher among PD patients. Familial mechanisms do not explain the association.
Ong et al. (2014)	Cohort study, All-England record-linked hospital and mortality dataset	Increased risk of melanoma, breast, uterine and renal cancers in PD.
Constantinescu et al. (2014)	Cohort study, National Institutes of Health (NIH) Exploratory Trials in PD (NET-PD) LS-1	The risk for developing melanoma was higher than expected in the NET-PD LS-1 cohort compared with the general population.
Peretz et al. (2016)	Retrospective, Cohort study, Israel	No difference in the risk of any type of cancer among PD patients.