A study has found that a combination of heavy alcohol use and cigarette smoking is the key factor in increasing the risk of upper aero-digestive cancers.
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.
A distinguished group of scientists from the International Agency for Research on Cancer (IRAC) evaluated the role of alcohol and tobacco consumption, based on 2,252 upper aerodigestive squamous-cell carcinoma cases and 1,707 controls from seven centres in Brazil, Argentina, and Cuba.
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.
Overall, this study confirms that there is a tendency for an increase in risk for these cancers for both alcohol consumption and for tobacco use.
An especially important finding in this study was that, among ex-drinkers and former smokers, the increased risks associated with alcohol and tobacco use decreased steadily as the time since quitting increased.
As stated by the authors, most of these cancers "could be prevented by quitting the use of either of these two agents".