2,3,7,8-Tetrachlorodibezo-p-dioxin exposure and prostate cancer: a meta-analysis of cohort studies.
OBJECTIVE
To perform a meta-analysis of cohort studies and evaluate the association between exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and prostate cancer quantitatively.


METHODS
Publications before April 2012 about populations exposed to TCDD were searched in PubMed. Only cohort studies were included. Extraction and quality assessment of included articles was performed independently by two authors using the MOOSE guidelines.


METHODS
A total of 17 cohort studies on prostate cancer with information about standardized mortality ratios (SMR), risk ratio (RR), standardized incidence ratios (SIR) and TCDD exposure were included. SMRs and RRs were pooled separately after weighing each study by calculating the inverse of the estimated variance.


RESULTS
Based on the 13 reported SMRs or SIRs, the meta-analysis yielded a meta-SMR of 1.26 (95% confidence interval 1.00-1.57, P = 0.046). The meta-RR, based on four reported RR from four cohorts, was 1.04 (95% confidence interval 0.85-1.28). Begg's funnel plot showed little evidence of publication bias (Egger's test P-value = 0.817).


CONCLUSIONS
This meta-analysis suggests that exposure to TCDD is associated with increased risk of prostate cancer.
Department of Occupational & Environmental Health, School of Public Health, Tianjin Medical University, Qixiangtai Road No. 22, Heping District, Tianjin 300070, China. Electronic address: lengling19871117@163.com.
L
L
Leng
Department of Occupational & Environmental Health, School of Public Health, Tianjin Medical University, Qixiangtai Road No. 22, Heping District, Tianjin 300070, China. Electronic address: chenxi@tijmu.edu.cn.
X
X
Chen
Department of Epidemiology & Statistics, School of Public Health, Tianjin Medical University, Qixiangtai Road No. 22, Heping District, Tianjin 300070, China. Electronic address: lichangping@tijmu.edu.cn.
C-P
CP
Li
Department of Epidemiology & Statistics, School of Public Health, Tianjin Medical University, Qixiangtai Road No. 22, Heping District, Tianjin 300070, China. Electronic address: luoxiaoyanhao@yahoo.com.cn.
X-Y
XY
Luo
Department of Occupational & Environmental Health, School of Public Health, Tianjin Medical University, Qixiangtai Road No. 22, Heping District, Tianjin 300070, China. Electronic address: tangnaijun@tijmu.edu.cn.
N-J
NJ
Tang
D015331:Cohort Studies; D016001:Confidence Intervals; D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D015994:Incidence; D008297:Male; D016017:Odds Ratio; D000072317:Polychlorinated Dibenzodioxins / Q000633:toxicity*; D011471:Prostatic Neoplasms / Q000139:chemically induced* / Q000453:epidemiology
D000072317:Polychlorinated Dibenzodioxins
Cohort study; Meta-analysis; Prostate cancer; Standardized mortality ratio; TCDD