Obesity may explain rising rate of esophageal and gastric cardia adenocarcinoma

November 15, 2007

NEW YORK (Reuters Health) - Increasing body mass index (BMI) is associated with an increased risk of esophageal and gastric cardia adenocarcinoma, and may account for the rising incidence of these diseases, researchers report.

"In the last decades, the incidence of adenocarcinoma of the esophagus and gastric cardia has increased rapidly in the United States and Western Europe, including the Netherlands," Dr. Audrey H. H. Merry, of Maastricht University, the Netherlands, and colleagues write in the November issue of Gut. "It has been suggested that the increasing prevalence of obesity in the Western world explains these trends in incidence of adenocarcinoma of the esophagus and gastric cardia."

To investigate, the researchers linked data from the Netherlands Cohort Study on Diet and Cancer, initiated in 1986, with annual cancer cases in the Netherlands Cancer Registry and the Netherlands Pathology Registry.

After 13.3 years of follow-up, complete data for case-cohort analyses were available for 4552 subcohort members, 133 cases of esophageal adenocarcinoma and 163 cases of gastric cardia adenocarcinoma.

The relative risks of esophageal adenocarcinoma for overweight (BMI 25.0 to 29.9) and obese subjects (BMI at least 30) were 1.40 and 3.96, respectively, compared to normal weight subjects (BMI 20.0 to 24.9).

The corresponding relative risks for gastric cardia adenocarcinoma were 1.32 and 2.73.

A positive association was observed between change in BMI during adulthood and the risk of esophageal and gastric cardia adenocarcinoma (p = 0.001 and 0.02, respectively). No association was found with BMI in early adulthood.

"A possible explanation for this strong association between BMI and risk of adenocarcinoma of the esophagus and gastric cardia is the effect of high BMI on gastro-esophageal reflux," Dr. Merry and colleagues suggest. They note that chronic reflux may lead to Barrett's esophagus, which may be a premalignant lesion for adenocarcinoma of the esophagus.