Cancer co-occurrence patterns in Parkinson's disease and multiple sclerosis-Do they mirror immune system imbalances?
To examine the site-specific cancer mortality among deaths registered with Parkinson's disease (PD) and multiple sclerosis (MS). We focused on the patterns related to the most frequent cancers.



We analyzed Swiss mortality data over a 39-year period (1969-2007), using a statistical approach applicable to unique daabases, i.e. when no linkage with morbidity databases or disease registries is possible. It was based on a case-control design with bootstrapping to derive standardized mortality ratios (SMR). The cases were defined by the cancer-PD or cancer-MS co-registrations, whereas the controls were drawn from the remaining records with cancer deaths (matching criteria: sex, age, language region of Switzerland, subperiods 1969-1981, 1982-1994, 1995-2007).



For PD we found lower SMRs in lung and liver cancer and higher SMRs in melanoma/skin cancer, and in cancers of breast and prostate. As for MS, the SMR in lung cancer was lower than expected, whereas SMRs in colorectal, breast and bladder cancer were higher.



A common pattern of associations can be observed in PD and MS, with a lower risk of lung cancer and higher risk of breast cancer than expected. Thus, PD and MS resemble other conditions with similar (schizophrenia) or reversed patterns (rheumatoid arthritis, immunosuppression after organ transplantation).
Epidemiology, Biostatistics and Prevention Institute, Swiss MS Registry, University of Zurich, Switzerland; Psychiatric Hospital, University of Zurich, Switzerland, Switzerland. Electronic address: vladeta.ajdacic-gross@uzh.ch.
Vladeta
V
Ajdacic-Gross
Epidemiology, Biostatistics and Prevention Institute, Swiss MS Registry, University of Zurich, Switzerland; Psychiatric Hospital, University of Zurich, Switzerland, Switzerland.
Stephanie
S
Rodgers
Psychiatric Hospital, University of Zurich, Switzerland, Switzerland.
Aleksandra
A
Aleksandrowicz
Epidemiology, Biostatistics and Prevention Institute, Swiss MS Registry, University of Zurich, Switzerland.
Margot
M
Mutsch
Epidemiology, Biostatistics and Prevention Institute, Swiss MS Registry, University of Zurich, Switzerland.
Nina
N
Steinemann
Epidemiology, Biostatistics and Prevention Institute, Swiss MS Registry, University of Zurich, Switzerland.
Viktor
V
von Wyl
Department of Neurology, Bern University Hospital, and Clinic Barmelweid, Switzerland.
Roland
R
von Känel
Epidemiology, Biostatistics and Prevention Institute, Swiss MS Registry, University of Zurich, Switzerland.
Matthias
M
Bopp
D000368:Aged; D015897:Comorbidity; D016208:Databases, Factual / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007107:Immune System / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000453:epidemiology*; D009369:Neoplasms / Q000145:classification / Q000150:complications / Q000453:epidemiology* / Q000276:immunology*; D010300:Parkinson Disease / Q000150:complications / Q000453:epidemiology*; D013557:Switzerland / Q000453:epidemiology
Cancer; Comorbidity; Epidemiology; Multiple sclerosis; Parkinson’s disease