Parkinson's Disease, Melanoma, and Keratinocyte Carcinoma: A Population-Based Study.

BACKGROUND: The association between Parkinson's disease (PD) and melanoma is well recognized, but its relationship with non-melanoma skin cancers has not been studied in depth.

OBJECTIVE: To assess the relationship between PD, and risk of melanoma and keratinocyte carcinoma: squamous cell carcinoma (SCC) and basal cell carcinoma (BCC).

METHODS: This historical cohort study used the data of 1.2 million adult members of a large health organization between 2000 and 2015. Individuals who were diagnosed with PD anytime between 2000 and 2010 were retrospectively followed until 8/2016 for incidence of SCC, BCC, or melanoma identified from physician diagnoses and pathology reports.

RESULTS: The PD cohort included 7,727 patients (mean [SD] age = 69.9 [14.8 years]) among the 1,251,695 study population. During follow-up, a total of 4,553, 32,069, and 4,015 cases of BCC, SCC, and melanoma were identified in the study population respectively. Multivariable models revealed that older age, male sex, never smoking, and residence in southern Israel and actinic keratosis were associated with an increased risk of both BCC and SCC. PD patients in the age range 45-64 and 65-84 years at baseline had an OR of 2.11 (95% CI 1.40-3.18) and 1.52 (95% CI 1.21-1.91) for BCC respectively. Weak or no associations were calculated for melanoma or SCC.

CONCLUSIONS: We report a positive relationship between PD and risk of BCC. These results should stimulate greater awareness on the part of healthcare providers to the increased risk of BCC in PD patients.