The distal esophagus is an important anatomic locus where gastric acid reflux causes reflux esophagitis (RE), Barrett’s esophagus (BE) (intestinal metaplasia), as well as esophageal adenocarcinoma (EA). Since 1975, the relative incidents have been stable for colon, lung, and breast cancers, moderately increased for the prostate cancer and melanoma, but grew about 6 fold for the esophageal adenocarcinoma, parallel to a significant increase in the prevalence of gastroesophageal reflux diseases (GERD). Although specific host factors might predispose one to disease risk, such a rapid increase in incidence must be predominantly environmental. The cause remains unknown.
Median survival of patients with esophageal adenocarcinoma appears to have slightly improved between 1971 and 2000, but, the patients continue to have a very poor prognosis. Surgery remains the only intervention that may significantly improve a patient's chance of survival. Without surgical intervention, 2-year survival for patients with esophageal adenocarcinoma remained essentially zero. (Crane SJ, et al. Survival trends in patients with gastric and esophageal adenocarcinomas: a population-based study. Mayo Clin Proc. 2008;83:1087-94)
This is a short list of previously identified risk factors in GERD. Of the host factors, hiatus hernia is the strongest predictive factor for GERD with an odds ratio of 4.2. For the environmental factors, tobacco use is the strongest factor with an odds ratio of only 2.6. These factors are not strong enough to explain the etiology of GERD.