Alcohol drinking and risk of renal cell carcinoma: results of a meta-analysis

The role of alcohol consumption in relation with renal cell carcinoma is still unclear; a few studies have reported a beneficial effect of moderate levels of alcohol consumption, whereas it remains still under debate whether there is a dose-response association. Twenty observational studies (4 cohort, 1 pooled and 15 case-control) reporting results on at least three levels of alcohol consumption were selected through a combined search with PubMed and EMBASE of articles published before November 2010. Overall relative risks (RRs) and 95% confidence intervals (CIs) were estimated using random-effects models, and both second-order fractional polynomials and random effect meta-regression models were implemented for the study of dose-risk relation. The estimated RRs were 0.85 (95% CI: 0.80-0.92) for any alcohol drinking, 0.90 (95% CI: 0.83-0.97) for light drinking (0.01-12.49 g/day), 0.79 (95% CI: 0.71-0.88) for moderate drinking (12.5-49.9 g/day) and 0.89 (95% CI: 0.58-1.39) for heavy drinking (>= 50 g/day), respectively. Our meta-analysis supports the hypothesis of a negative effect of moderate alcohol consumption on the risk of renal cell cancer.