Colon cancer is diagnosed at an earlier age in smokers and drinkers

Current smoking and alcohol use reduces the average age of colorectal cancer diagnosis by nearly 8 years over the age at diagnosis for those who have never smoked or used alcohol.  This effects was even greater for women, who were diagnosed 9.2 years earlier.

In a recent study, people with colorectal cancer who had never smoked or used alcohol were diagnosed with colorectal cancer at an average age of 71.3 years.  However, those who were current smokers and also current drinkers, were first told they had colorectal cancer at age 62.6. 

Reviewing a large database of 167.000 people diagnosed with colorectal cancer, researchers looked at tobacco us (current, past, or never) and alcohol use (current, past, or never) in both men and women.  They also reviewed the local in the colon (proximal or distal) where the cancer was found.

Current smokers who were not drinkers were diagnosed 3.7 years earlier for men and 6.3 years earlier for women.

People who had used alcohol in the past year (current drinkers) but did not smoke were diagnosed about an average of 5 years earlier — for both men and women.

There appeared to be no difference in age of diagnosis for people who had used tobacco and alcohol in the past leading the researchers to believe that stopping smoking or alcohol use could reduce risk somewhat.

Alcohol and tobacco use was also associated with where the cancer was located, with more cancers found distally — nearer the end of the intestinal tract — in current smokers and drinkers.  Women who had never smoked or used alcohol were more likely to have tumors in the proximal colon and perhaps should consider colonoscopy rather than sigmoidoscopy for screening.

Hermant. K. Roy and his colleagues at the Feinberg School of Medicine at Northwestern University published their report in the Archives of Internal Medicine, March 27, 2006

Our report provides compelling evidence that modifiable risk factors such as alcohol and tobacco use are associated with a younger age at diagnosis and a predilection for distal CRCs.These data underscore the need for cessation of alcohol and tobacco use as an integral part of a CRC prevention program.If replicated in other data sets, our findings would argue that screening should be initiated at a younger age in alcohol and tobacco users. Moreover, these factors help define a subgroup at risk for proximal CRC (non drinking and non smoking women) among whom total colonoscopy rather than flexible sigmoidoscopy would be more appropriate. In the future, we envision the development of risk scores with exogenous (eg, alcohol and tobacco use, age, body mass index, diet, and calcium consumption) and hereditary factors to tailor an individual’s CRC screening program.

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