Proportion of cancer cases and deaths attributable to lifestyle risk factors in Brazil

Background: Lifestyle risk factors (tobacco smoking, alcohol consumption, overweight and obesity, unhealthy diet, and lack of physical activity) have been associated with increased risk of at least 20 types of cancer. We estimated the proportion of cancer cases and deaths that could be potentially avoided by eliminating or reducing lifestyle risk factors in Brazil. Methods: We obtained the distribution of lifestyle risk factors by sex and age groups from recent representative health surveys in Brazil; relative risks from pooled analyses of prospective studies and meta-analyses; and cancer cases and deaths in 2012 from GLOBOCAN. Results: We found that 26.5% (114,497 cases) of all cancer cases and 33.6% (63,371 deaths) of all cancer deaths could be potentially avoided by eliminating lifestyle risk factors in Brazil. Plausible reductions in these exposures based on policy targets and cancer prevention recommendations could have potentially avoided 4.5% (19,731 cases) and 6.1% (11,480 deaths) of all cancer cases and deaths, respectively. Tobacco smoking accounted for most of the preventable cancer cases and deaths, followed by high body mass index and alcohol consumption. Larynx, lung, oropharynx, esophagus and colorectum cancer cases and deaths could be at least halved by eliminating these lifestyle risk factors. Conclusion: Findings from this study may be useful to inform strategies for cancer prevention and control across Brazil.