Effects of stopping alcohol consumption on subsequent risk of esophageal cancer

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.

Reference: Jarl J, Gerdtham Ulf-G. Time pattern of reduction in risk of oesophageal cancer following alcohol cessation — a meta-analysis. Addiction, 107, 1234. doi:10.1111/j.1360-0443.2011.03772.x

Contributions to this critique by the International Scientific Forum on Alcohol Research were provided by the following members:

Luc Djoussé, MD, DSc, Dept. of Medicine, Division of Aging, Brigham & Women's Hospital and Harvard Medical School, Boston, MA, USA

Gordon Troup, MSc, DSc, School of Physics, Monash University, Victoria, Australia

Harvey Finkel, MD, Hematology/Oncology, Boston University Medical Center, Boston, MA, USA

Arne Svilaas, MD, PhD, general practice and lipidology, Oslo University Hospital, Oslo, Norway

David Van Velden, MD, Dept. of Pathology, Stellenbosch University, Stellenbosch, South Africa

Andrew L. Waterhouse, PhD, Marvin Sands Professor, Department of Viticulture and Enology, University of California, Davis; Davis, CA, USA

Erik Skovenborg, MD, Scandinavian Medical Alcohol Board, Practitioner, Aarhus, Denmark

R. Curtis Ellison, MD, Section of Preventive Medicine & Epidemiology, Boston University School of Medicine, Boston, MA, USA

For the detailed critique of this paper by the International Scientific Forum on Alcohol Research and a listing of references, go to http://www.bu.edu/alcohol-forum/critique-090-effects-of-stopping-alcohol-consumption-on-subsequent-risk-of-esophageal-cancer-13-september-2012/

The specialists who are members of the Forum are happy to respond to questions from Health Editors regarding emerging research on alcohol and health and will offer an independent opinion in context with other research on the subject.