CHAPTER 7: Alcohol Intake and Cancer Risk

Alcohol is classified as a group I carcinogen and is considered an important cause of cancer, corresponding to 12.6% of all cancer-related deaths worldwide. Heavy alcohol consumption has been linked to an increased risk for various types of cancers in humans, especially those associated with the gastrointestinal tract, such as the oral cavity, esophagus, stomach, liver, colon, rectum and pancreas. Several mechanisms are described in the pathogenesis of alcohol-associated gastrointestinal cancers. Acetaldehyde, a toxic product of alcohol metabolism, has been proposed as the main carcinogenic compound, which causes DNA damage and genomic instability after heavy alcohol consumption. Indeed, acetaldehyde exhibits local carcinogenic actions on the mucosa of the gastrointestinal tract, which has potential synergistic effects with other risk factors, such as smoking. This chapter will revise the evidence on the epidemiological association and mechanistic studies linking alcohol consumption with the risk of several types of gastrointestinal cancers.