61, 62] showing no association, and other hospital-based [29, 30] and population-based case–control [15, 16, 18] and cohort [20, 21, 34, 36, 37, 41, 63] studies suggesting increased risk. Discordant observations in the published literature may be due to small numbers of cases, residual confounding by risk factors associated with alcohol consumption such as smoking and chronic pancreatitis, unmeasured genetic factors, or absence of detailed data on alcohol exposure [16, 17, 23, 34, 39].
