Loading...
Cigarette smoking has been associated with increased risk for colorectal cancer (CRC) in multiple studies. Investigators recently performed a meta-analysis to determine the magnitude of the risk.
The final analyses included 106 independent studies of CRC incidence and 17 of CRC mortality. In the 25 studies that provided adjusted risk estimates for ever-smokers versus never-smokers, the pooled relative risk for developing CRC was 1.18 for the ever-smokers (95% CI, 1.11–1.26). Risk rose with increased daily cigarette consumption; risk also rose with increased duration of smoking, but the difference became significant only after 30 years of smoking. In the 15 studies for which CRC mortality could be compared between ever- and never-smokers, the…