Comorbid cancer in Parkinson's disease

Abstract

The aim of this article was to evaluate cancer occurrence before and after diagnosis of Parkinson's disease (PD). We investigated 692 patients newly diagnosed with PD and 761 age- and sex-matched control subjects identified during two periods (1994-1995 and 2000-2003) within Kaiser Permanente Medical Care Program of Northern California. Primary cancers were searched and dated, and all participants were followed up until the end of membership, death, or December 31, 2008. We used unconditional logistic regression to evaluate the PD-cancer association before the date of PD diagnosis or the index date and Cox proportional hazards regression to evaluate the PD-cancer association after the index date. Nearly 20% (140 of 692) of the PD patients and 25% (188 of 761) of the non-PD controls had ever had a cancer diagnosis. Before the index date, the prevalence of cancer was not significantly lower in patients with PD (8.1% PD vs. 9.2% controls; OR = 0.83; 95% CI 0.54-1.3). After the index date, the risk of developing a cancer did not differ between PD cases and controls (relative risk [RR] = 0.94; 95% CI 0.70-1.3). Among specific cancers, melanoma was more common among PD cases (before PD, OR = 1.5; 95% CI 0.40-5.2; after PD, RR = 1.6; 95% CI 0.71-3.6), but independent of dopaminergic therapy. Cancer occurrence is not significantly lower among patients with PD. The positive association between PD and subsequent melanoma merits further investigation, as it does not seem to be attributable to dopaminergic therapy, pigmentation, or confounding by smoking.

Inverse and Direct Cancer Comorbidity in People with Central Nervous System Disorders: A Meta-Analysis of Cancer Incidence in 577,013 Participants of 50 Observational Studies

“…Forty-three cohort studies were included, of which 8 had a prospective design and 35 had a retrospective design, and 8 were nested case-control studies. Three reports [7,23,24] contained data on cancer comorbidity in patients with AD, 11 in PD [25,26,27,28,29,30,31,32,33,34,35], 9 in MS [32,36,37,38,39,40,41,42,43], 2 in ALS [32,44], 19 in SCZ [45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63], 6 in DS [3,64,65,66,67,68], 2 in HD [69,70] and 1 in ASD [71]. Patient data were collected from population-based registries in 38 of the studies, of which 13 were hospital based.…”

Meta-analysis of the relationship between Parkinson disease and melanoma

“…Among the 14 studies on melanoma and PD, 6 were case-control studies, 6,9,[17][18][19] 7 were cohort studies 7,10,13,20 -22 or nested case-control studies, 17,18 and one was a cross-sectional study. 23 Only 2 21,23 of the 14 studies were explicitly designed to assess the relationship between melanoma and PD, whereas others assessed melanoma as part of their analyses on PD and other site-specific cancers or medical conditions of interest.…”

“…23 Only 2 21,23 of the 14 studies were explicitly designed to assess the relationship between melanoma and PD, whereas others assessed melanoma as part of their analyses on PD and other site-specific cancers or medical conditions of interest. In these studies, PD cases were identified from hospitalization records, 6,7,13 computerized medical records, 9,18,20 self-report, 17,22 or clinical studies on PD. 10,19,21,23 Ascertainments of melanoma and nonmelanoma skin cancers in these studies were based on cancer registry, 6,7,9 medical records, 17,18,20,22 self-reports, 19 hospitalization records, 13 clinical trial records, 21 or examinations by a dermatologist.…”

“…Four articles [5][6][7][8] examined the relationship between skin cancers and PD using similar data from the Danish National Hospital Register; however, we included only the two 6,7 that provided the most comprehensive data. During the preparation of the current meta-analysis, we noted that 2 additional articles 9,10 were published online and met our inclusion criteria. Thus, a total of 12 publications were included in the meta-analysis for melanoma and PD.…”

“…Two articles 9,13 reported results on melanoma occurrence both before and after PD diagnosis in the same publication; the two analyses described in each of these two articles were treated as separate studies in the meta-analysis. Therefore, we extracted data from a total of 14 studies (described in 12 publications) for the analyses on melanoma and PD.…”