Alcohol consumption is a major cause of disease and death. In a previous study, we reported that in 2002, 3.6% of all cases of cancer and a similar proportion of cancer deaths were attributable to the consumption of alcohol. We aimed to update these figures to 2012 using global estimates of cancer cases and cancer deaths, data on the prevalence of drinkers from the World Health Organization (WHO) global survey on alcohol and health, and relative risks for alcohol-related neoplasms from a recent meta-analysis. Over the 10-year period considered, the total number of alcohol-attributable cancer cases increased to approximately 770,000 worldwide (5.5% of the total number of cancer cases)-540,000 men (7.2%) and 230,000 women (3.5%). Corresponding figures for cancer deaths attributable to alcohol consumption increased to approximately 480,000 (5.8% of the total number of cancer deaths) in both sexes combined-360,000 (7.8%) men and 120,000 (3.3%) women. These proportions were particularly high in the WHO Western Pacific region, the WHO European region and the WHO South-East Asia region. A high burden of cancer mortality and morbidity is attributable to alcohol, and public health measures should be adopted in order to limit excessive alcohol consumption.In 2012, 38.1% of the world's population aged 15 years or older were estimated to be regular drinkers, with an average consumption among drinkers of 38.6 g of pure alcohol per day (approximately 3.2 drinks) (calculations based on http:// www.who.int/gho/alcohol/en/; see also Ref. 1); however, there was considerable variation in the prevalence of drinking across the regions of the world.1 Alcohol is one of the primary risk factors for morbidity, disability and mortality worldwide. 1 The impact of alcohol consumption on head and neck cancers and on esophageal squamous cell carcinoma (SCC) has long been known, 2 even at low levels of consumption, 3 but the number of cancers associated with alcohol consumption has increased in recent years, and currently includes cancers of the colon, rectum, liver, female breast 4 and with limited evidence and for high levels of consumption, pancreas.5 Moreover, a recent meta-analysis suggested a weak positive association between alcohol consumption and cancers of the gallbladder, prostate, lung, stomach and melanoma. 6 In a previous study, we reported that in 2002, 3.6% of all cancer cases and a similar proportion of cancer deaths were attributable to alcohol. 7 We aimed to update these results to 2012 and estimate the worldwide burden of cancer attributable to alcohol by combining up-to-date relative risk (RR) estimates of cancer, the global prevalence of drinkers and global estimates of cancer cases and cancer deaths.
MethodsWe computed the overall and sex-specific number of cases and deaths of the main alcohol-related cancers, 6 including oral cavity and pharynx, esophagus (SCC only), colon and