Barrett's esophagus (BE) patients who smoke tobacco are at a two-fold increased risk of developing esophageal cancer, according to a new study in Gastroenterology, the official journal of the American Gastroenterological Association. BE patients who smoke also double their risk for developing advanced precancerous cells.
"We found that tobacco smoking emerged as the strongest lifestyle risk factor for cancer progression. Contrary to popular belief, alcohol consumption didn't increase cancer risk in this group of patients with Barrett's esophagus," said Helen G. Coleman, PhD, of Queen's University Belfast in Northern Ireland and the lead author of this study.
While analyzing data (ranging from 1993 to 2005) from one of the largest population-based cohorts of more than 3,000 BE patients worldwide, doctors found that by Dec. 31, 2008, 117 of the patients developed dysplasia or cancers of the esophagus or stomach. For the first time in such a large study, researchers were able to get information about smoking at the time a person was first diagnosed with BE to see how this influenced cancer risk years later. This is important for reducing bias known to be associated with asking patients about their smoking habits in the past.
Current tobacco smoking, regardless of the number of daily cigarettes, was significantly associated with an increased risk of esophageal cancer. This suggests that reducing the number of cigarettes smoked per day may not reduce the risk of cancer in BE patients.
The incidence of esophageal cancer is on the rise in developed countries. It originates from the premalignant condition BE, presumably progressing through low- and high-grade dysplasia (precancerous cells). However, progression along this pathway is uncommon, and the vast majority of BE patients never develop esophageal cancer or high-grade dysplasia. Factors distinguishing the small minority of patients who do progress remain largely elusive. This underscores the importance of identifying modifiable lifestyle factors that may contribute to cancer progression.
"Tobacco smoking has been long established as highly carcinogenic," added Dr. Coleman. "Barrett's esophagus patients who smoke should start a cessation program immediately."
Although these findings need to be confirmed in future studies, the study's researchers suggest that tobacco smoking be discouraged and smoking-cessation strategies considered in BE patients in order to reduce future cancer risk. Further, identifying modifiable lifestyle factors that influence cancer progression may provide an additional cost-effective method of alleviating future cancer burden in this patient group.
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