Patients with at least five biopsies showing nondysplastic Barrett’s esophagus were statistically as likely to progress to high-grade dysplasia or esophageal adenocarcinoma as patients with a single such biopsy, according to a multicenter prospective registry study reported in the June issue of Clinical Gastroenterology and Hepatology (doi: org/10.1016/j.cgh.2017.02.019).
The findings, which contradict those from another recent multicenter cohort study (Gastroenterology. 2013;145[3]:548-53), highlight the need for more studies before lengthening the time between surveillance biopsies in patients with nondysplastic Barrett’s esophagus, Rajesh Krishnamoorthi, MD, of Mayo Clinic in Rochester, Minn., wrote with his associates.
Barrett’s esophagus is the strongest predictor of esophageal adenocarcinoma, but studies have reported mixed results as to whether the risk of this cancer increases over time or wanes with consecutive biopsies that indicate nondysplasia, the researchers noted. Therefore, they studied the prospective, multicenter Mayo Clinic Esophageal Adenocarcinoma and Barrett’s Esophagus registry, excluding patients who progressed to adenocarcinoma within 12 months, had missing data, or had no follow-up biopsies. This approach left 480 subjects for analysis. Patients averaged 63 years of age, 78% were male, the mean length of Barrett’s esophagus was 5.7 cm, and the average time between biopsies was 1.8 years, with a standard deviation of 1.3 years.
A total of 16 patients progressed to high-grade dysplasia or esophageal adenocarcinoma over 1,832 patient-years of follow-up, for an overall annual risk of progression of 0.87%. Two patients progressed to esophageal adenocarcinoma (annual risk, 0.11%; 95% confidence interval, 0.03% to 0.44%), while 14 patients progressed to high-grade dysplasia (annual risk, 0.76%; 95% CI, 0.45% to 1.29%). Eight patients progressed to one of these two outcomes after a single nondysplastic biopsy, three progressed after two such biopsies, three progressed after three such biopsies, none progressed after four such biopsies, and two progressed after five such biopsies. Statistically, patients with at least five consecutive nondysplastic biopsies were no less likely to progress than were patients with only one nondysplastic biopsy (hazard ratio, 0.48; 95% CI, 0.07 to 1.92; P = .32). Hazard ratios for the other groups ranged between 0.0 and 0.85, with no significant difference in estimated risk between groups (P = .68) after controlling for age, sex, and length of Barrett’s esophagus.
The previous multicenter cohort study linked persistently nondysplastic Barrett’s esophagus with a lower rate of progression to esophageal adenocarcinoma, and, based on those findings, the authors suggested lengthening intervals between biopsy surveillance or even stopping surveillance, Dr. Krishnamoorthi and his associates noted. However, that study did not have mutually exclusive groups. “Additional data are required before increasing the interval between surveillance endoscopies based on persistence of nondysplastic Barrett’s esophagus,” they concluded.
The study lacked misclassification bias given long-segment Barrett’s esophagus, and specialized gastrointestinal pathologists interpreted all histology specimens, the researchers noted. “The small number of progressors is a potential limitation, reducing power to assess associations,” they added.
The investigators did not report funding sources. They reported having no conflicts of interest.