Significantly more people who suffer from Barrett's esophagus, a precancerous condition often associated with frequent heartburn, may be at high risk of developing esophageal cancer than previously thought, according to researchers at the Fred Hutchinson Cancer Research Center in Seattle. These findings, by Rebecca Rudolph, M.D., M.P.H., and colleagues, appear today in the Annals of Internal Medicine.
An estimated 20 million Americans experience chronic heartburn that goes well beyond the occasional misery of having one too many chili dogs. About 2 million of these people have Barrett's esophagus, a premalignant condition of the esophagus, the tube that carries food from the mouth to the stomach. While the condition is most prevalent in middle-aged white men, the incidence of Barrett's esophagus is rising in women and African Americans. A physician may suspect that the condition is present if part of the inner lining of the esophagus is red rather than the usual light pink. This is determined through a procedure called endoscopy, in which a tubelike instrument is used to view the esophageal lining. However, a definite diagnosis cannot be made unless small samples of the red lining are biopsied, or removed and examined under a microscope, and found to have cellular changes typical of this disorder.
People with "long-segment" Barrett's esophagus, in which the red lining is 3 cm or more in length, are about 40 times more likely than those in the general population to develop esophageal cancer. As a result, they typically undergo regular endoscopic screening and biopsies to ensure their condition has not progressed to cancer.
Substantially more common, however, is "short-segment" Barrett's, in which the patch of affected tissue is no more than 3 cm long. Until recently, esophageal-cancer risk in people with shorter segments was largely unknown because such patients often were excluded from studies because their condition was more difficult to diagnose through endoscopy, and because researchers initially were uncertain whether short-segment Barrett's indeed was a cancer risk factor at all.
Rudolph and colleagues at the Hutchinson Center and the University of Washington have found that, contrary to popular belief, the risk of esophageal cancer in patients with short-segment Barrett's is not substantially lower than in patients with longer patches of affected tissue. "The general feeling among gastroenterologists has been that people with short- segment Barrett's are probably at a much lower risk of developing esophageal cancer, and so it is possible that these people aren't being monitored as aggressively as they should," says Rudolph, the lead author of the study. The study, the largest single-center trial of its kind, involved 309 Barrett's patients, primarily from the Puget Sound area, who were followed and closely monitored for four years.
Barrett's-related esophageal cancer strikes about 10,000 people a year, and for unknown reasons, the incidence is rising faster than that of any other cancer in the United States. Barrett's-related cancers tripled between 1976 and 1990, and more than doubled in the past decade. If not diagnosed early, the outlook is grim; more than 90 percent of patients with invasive esophageal adenocarcinoma die within five years of diagnosis. Currently, the recommended screening frequency for Barrett's esophagus ranges from once every three to six months to once every two to three years, depending on segment length and the degree of dysplasia, or cellular abnormality, detected under the microscope upon biopsy.
"Until more data is available, the frequency of endoscopic surveillance should be determined without regard to the patient's segment length," says Rudolph, a clinical specialist in the Center's Public Health Sciences Division. "For now, people with short-segment Barrett's should be treated exactly the same as people with long-segment Barrett's."
Senior authorship of the study was shared by Brian Reid, M.D., Ph.D., a member of the Center's Clinical, Human Biology and Public Health Sciences divisions and a professor of gastroenterology at UW; and Thomas Vaughan, M.D., M.P.H., a member of the Center's Public Health Sciences Division and a professor of epidemiology at the UW School of Public Health and Community Medicine.
This research was supported by grants from the National Institutes of Health.
Editor's note: A copy of the paper "Effect of Segment Length on Risk for Neoplastic Progression in Patients with Barrett Esophagus" is available on the journal's Web site, http://www.
The Fred Hutchinson Cancer Research Center is an independent, nonprofit research institution dedicated to the development and advancement of biomedical technology to eliminate cancer and other potentially fatal diseases. Recognized internationally for its pioneering work in bone-marrow transplantation, the Center's four scientific divisions collaborate to form a unique environment for conducting basic and applied science. The Hutchinson Center is the only National Cancer Institute-designated comprehensive cancer center in the Pacific Northwest. For more information, visit the Center's Web site at http://www.