Cessation of drinking may reduce risk of oesophageal cancer

Boston University Medical CenterSep 14 2012

Cancer of the oesophagus is becoming more common in Europe and North America. Around 7,800 people in the UK are diagnosed each year. The exact causes of this cancer aren't fully understood. It appears to be more common in people who have long-term acid reflux (backflow of stomach acid into the oesophagus). Other factors that can affect the risk of developing cancer of the oesophagus include:

• Gender - It is more common in men than in women.
• Age - The risk of developing oesophageal cancer increases as we get older. It occurs most commonly in people over 45.
• Smoking - The longer a person smokes and the more tobacco they smoke, the greater the risk.
• Alcohol - Drinking a lot of alcohol over a long period of time increases your risk, especially if you smoke too.
• Diet - Having a diet low in fresh fruit and vegetables is linked to an increased risk of oesophageal cancer.
• Obesity - Being overweight is associated with a higher risk. This is thought to be because long-term acid reflux is more common in people who are overweight.

This paper looks at the effect of giving up alcohol on the risk of oesophageal cancer: it is based on 17 studies providing such information, 9 of which provided data for a meta-analysis. The authors conclude that an alcohol-related increased risk of oesophageal cancer is reversible following giving up alcohol, taking up to 16 years to return to the risk level for non-drinkers. The authors estimate that about one-half of the reduction in risk of cancer may occur within in a much shorter time, perhaps within about 4 or 5 years.

Forum reviewers considered this to be a well-done analysis. Forum members emphasized, as did the authors, a number of limitations of the study. Adjustments for smoking may not have been adequate: most upper aero-digestive cancers show a strong interaction between smoking and alcohol consumption in relation to cancer risk, (there is little effect of moderate alcohol consumption among non-smokers found in studies).

Further, large differences in the alcohol-cancer association were shown in this study for different geographical regions (some associations being much higher in Asia than in Europe or North America), but such differences were not adjusted for in the main analyses. The fact that the authors of this paper did not have data permitting the separation of ex-drinkers and never drinkers (both groups being included in the "non-drinker" category), and their inability to judge the effects of the baseline pattern of drinking (regular versus binge drinking), may also be limitations to the interpretation of their results. Adjustment for such factors may have influenced the effects of stopping drinking on subsequent cancer risk, and markedly changed the calculated effects on the numbers of cancers prevented worldwide.

In any case, the fact that cessation of drinking may reduce the risk of oesophageal cancer is of importance. Other studies suggest further that reducing the amount of alcohol consumed to moderate levels rather than the complete cessation of drinking, may be associated with lowering of cancer risk among non-smokers, and low-level regular alcohol intake has been shown to have beneficial health effects on cardiovascular disease, diabetes, and other medical conditions.