What is acid reflux?

Patients with long-segment Barrett esophagus have an estimated 30 to 125 times increased risk of developing esophageal cancer compared with the general population. Early studies suggested that the median cancer incidence was 1 per 100 patient-years of follow-up, but more recent studies with longer follow-up suggest a lower cancer rate of 1 per 200 to 250 patient-years. This is an annual incidence of approximately 0.5%, with about 500 cases of adenocarcinoma diagnosed annually. However, since the early 1980s, the incidence of squamous cell carcinoma has stayed constant, whereas the incidence of adenocarcinoma of the esophagus and esophagogastric junction has risen fivefold—a growth rate exceeding that of any other cancer. Currently, adenocarcinoma accounts for more than half of all esophageal cancers in the United States. Despite this cancer risk, most patients with Barrett esophagus die of unrelated causes. More than 90% of patients who develop cancer present with symptoms caused by the tumor itself and are unaware of their antecedent Barrett esophagus. Epidemiologic data suggest that the mean interval from developing Barrett esophagus to evolution to cancer may be 20 to 30 years.

Management of patients with Barretts metaplasia has two aspects: treating the underlying GERD and managing the risk of adenocarcinoma of the esophagus. The principles for treating peptic esophagitis and controlling symptoms in Barretts metaplasia are the same as for uncomplicated GERD with the proviso that because it is associated with extreme esophageal acid exposure, it will likely require more intensive treatment. In general, mucosal damage and symptoms can be controlled with proton pump inhibitor therapy, but surgery may be needed, or even desirable, in refractory cases.
On the basis of in vitro and in vivo cell proliferation studies reporting increased cell proliferation and decreased differentiation in tissue exposed to acid, some authorities believe that complete acid suppression is desirable in therapy for Barretts metaplasia. However, there is no clinical evidence that aggressive antisecretory therapy or antireflux surgery prevents the occurrence of adenocarcinoma or causes regression of intestinal metaplasia. Proton pump inhibitor therapy has proved to be of no avail in reversing metaplasia or preventing adenocarcinoma. Thus, the available data support titrating therapy to control symptoms and treat esophagitis, irrespective of the presence of Barretts metaplasia.