Plasma organochlorines and subsequent risk of prostate cancer in Japanese men: a nested case-control study.
BACKGROUND
Although accumulating evidence suggests that exposure to organochlorine pesticides and polychlorinated biphenyls (PCBs) may contribute to the development of prostate cancer, few investigations have used biological samples to classify exposure to specific organochlorines. To our knowledge, this is the first prospective study to investigate the association between blood levels of organochlorines and prostate cancer risk.


METHODS
We conducted a nested case-control study using data from the Japan Public Health Center-based Prospective (JPHC) Study. A total of 14,203 men 40-69 years old who returned the baseline questionnaire and who provided blood samples were followed from 1990 to 2005. Using a mean follow-up period of 12.8 years, we identified 201 participants who were newly diagnosed with prostate cancer. Two matched controls for each case were selected from the cohort. We used a conditional logistic regression model to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for prostate cancer in relation to plasma levels of nine organochlorines: PCBs, dichlorodiphenyltrichloroethane (DDT), hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), trans- and cis-nonachlor, oxychlordane, and mirex.


RESULTS
No statistically significant association with total prostate cancer was seen for any plasma organochlorine, although we did observe an insignificant inverse association for plasma HCB and beta-HCH. Total PCB in plasma was also inversely associated with advanced prostate cancer but without statistical significance.


CONCLUSIONS
Our results suggest that no overall association exists between prostate cancer and organochlorines at the levels measured in our study population.
Sawada
Norie
N
Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan. nsawada@ncc.go.jp
Iwasaki
Motoki
M
Inoue
Manami
M
Itoh
Hiroaki
H
Sasazuki
Shizuka
S
Yamaji
Taiki
T
Shimazu
Taichi
T
Tsugane
Shoichiro
S
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015331:Cohort Studies; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood* / Q000633:toxicity*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D010575:Pesticides / Q000097:blood* / Q000633:toxicity*; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000209:etiology*; D012307:Risk Factors
D006843:Hydrocarbons, Chlorinated; D010575:Pesticides