title: Cancer in Parkinson's disease.
abstract: We examined the prevalence of cancer in patients with Parkinson's disease (PD) and controls evaluated at the Mayo Clinic in Jacksonville, Florida, between 2003 and 2014.
  
  
  
  We retrospectively collected information regarding cancer diagnoses and diagnosis of PD from 971 unrelated PD patients and 478 controls, and all were white. For PD patients, we examined cancers diagnosed before and after PD diagnosis separately in addition to considering all cancer diagnoses.
  
  
  
  Twenty different cancers were identified. In PD patients, the most common types of cancer were skin cancer (17.3% overall; 10.6% before PD), followed by nonmelanoma skin cancer (16.0% overall; 9.7% before PD), prostate cancer in men (12.8% overall; 9.2% before PD), breast cancer in women (10.6% overall; 6.3% before PD), and melanoma (2.4% overall; 1.1% before PD). Compared to controls, a significantly lower frequency of nonmelanoma skin cancer (odds ratio [OR]: 0.62, P = 0.0024) and any skin cancer (OR: 0.57, P = 0.0002) was observed in PD patients. These differences were greater when considering only cases with cancers that occurred before PD diagnosis (OR: 0.49, P < 0.0001; OR: 0.45, P < 0.0001, respectively), and there was a lower frequency of melanoma and any cancer preceding PD diagnosis compared to controls (OR: 0.31, P = 0.003; OR: 0.36, P < 0.0001). There was no evidence of a frequency difference for any other cancer.
  
  
  
  PD patients had a lower frequency of skin cancers or any cancer prior to PD diagnosis compared to controls, suggesting that cancer may have a protective effect on PD risk.
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: tacik.pawel@mayo.edu.
authors.forename: Pawel
authors.initials: P
authors.lastname: Tacik
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: sadie.e.curry@gmail.com.
authors.forename: Sadie
authors.initials: S
authors.lastname: Curry
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA; Department of Neurology, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, Fukuoka 814-0180, Japan. Electronic address: shinsuke@cis.fukuoka-u.ac.jp.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Fujioka
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: strongosky.audrey@mayo.edu.
authors.forename: Audrey
authors.initials: A
authors.lastname: Strongosky
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: uitti@mayo.edu.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Uitti
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: vangerpen.jay@mayo.edu.
authors.forename: Jay A
authors.initials: JA
authors.lastname: van Gerpen
authors.affiliation: Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: diehl.nancy@mayo.edu.
authors.forename: Nancy N
authors.initials: NN
authors.lastname: Diehl
authors.affiliation: Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: heckman.michael@mayo.edu.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Heckman
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road South, Jacksonville, FL, 32224, USA. Electronic address: Wszolek.Zbigniew@mayo.edu.
authors.forename: Zbigniew K
authors.initials: ZK
authors.lastname: Wszolek
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000145:classification / Q000453:epidemiology*; D010300:Parkinson Disease / Q000453:epidemiology*; D012189:Retrospective Studies; D055815:Young Adult
keywords: Basal ganglia; Cancer; Melanoma; Parkinsonism; Parkinson’s disease; Primary brain tumor