Upper aero-digestive tract cancers (UADT), especially those of the oral cavity, pharynx, and larynx, are often referred to as alcohol-related cancers as it has been shown repeatedly that heavy drinkers, in particular, are at increased risk. The combination of heavy alcohol use and cigarette smoking is the key factor in increasing the risk of these cancers.
The case-control analysis showed that both alcohol consumption and smoking tended to increase the risk of such cancers. However, the predominant cause of these cancers was the combination of smoking and alcohol consumption, with much higher risk than either exposure alone.
The effects on risk were greater for smoking than for alcohol: for non-smokers, there was little effect of alcohol alone on risk. For non-drinkers, the risk of cancer associated with smoking was still increased, but was lower than it was for current drinkers.