Advances in Barrett's esophagus and esophageal adenocarcinoma.

Despite advances in diagnosis and therapy, esophageal adenocarcinoma remains an aggressive and usually lethal tumor. This review focuses on the epidemiology of esophageal adenocarcinoma and its presumed precursor lesion, Barrett's esophagus; the pathogenesis of the cancer; advances in treatment of adenocarcinoma and Barrett's esophagus; and strategies for cancer prevention. Emphasis is placed on recent literature. Although the absolute number of cases of adenocarcinoma in the United States is still small, the incidence of this cancer has increased dramatically in the last 40 years, and adenocarcinoma is now the predominant form of esophageal cancer in this country. Recent evidence suggests that Barrett's esophagus is more prevalent in asymptomatic individuals than previously appreciated. The pathogenesis of Barrett's esophagus is poorly understood. Given that some subjects will have repeated bouts of severe erosive esophagitis and never develop Barrett's esophagus, host factors must play an important role. The utility of neoadjuvant radiation and chemotherapy in those with adenocarcinoma, although they are widely practiced, is not of clear benefit, and some authorities recommend against it. Ablative therapies, as well as endoscopic mucosal resection, hold promise for those with superficial cancer or high-grade dysplasia. Most series using these modalities feature relatively short follow-up, and longer-term data will be necessary to better describe the effects of these therapies. The value of chemoprevention in subjects with dysplastic Barrett's esophagus by use of cyclooxygenase 2 inhibitors, nonsteroidal anti-inflammatory drugs, or proton pump inhibitors is unknown. Similarly, although endoscopic screening is widely practiced, its value in patients with chronic gastroesophageal reflux disease symptoms is of unproven value, and recommending bodies are divided as to its practice.