Quantified relations between exposure to tobacco smoking and bladder cancer risk: a meta-analysis of 89 observational studies.

Background: Smoking is a major risk factor for bladder cancer (BC). This meta-analysis updates previous reviews on smoking characteristics and BC risk, and provides a more quantitative estimation of the dose-response relationship between smoking characteristics and BC risk.

Methods: In total, 89 studies comprising data from 57 145 BC cases were included and summary odds ratios (SORs) were calculated.