Low Risk of High-Grade Dysplasia or Esophageal Adenocarcinoma Among Patients With Barrett's Esophagus Less Than 1 cm (Irregular Z Line) Within 5 Years of Index Endoscopy

BACKGROUND & AIMS: Many patients with a < 1 cm segment of columnar metaplasia in the distal esophagus, also called an irregular Z line, are encountered. These patients, often referred to as patients with Barrett's esophagus (BE), are enrolled in surveillance programs. However, little is known about their risk of high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC). We aimed to determine the incidence of HGD and EAC in patients with irregular Z line with intestinal metaplasia. METHODS: We performed a prospective, multicenter cohort study of patients who underwent endoscopic examination for BE at tertiary care referral centers in the United States and Europe. We analyzed data from 1791 patients (mean age, 56 +/- 17 years) found to have non-dysplastic BE at the index endoscopy and after 1 year or more of follow-up. Patients were followed for a median of 5.9 years (interquartile range, 3.1-8.3 years). We calculated rates of progression to HGD or EAC between groups of patients with irregular Z line (n = 167) and those with BE of >= 1 cm (n = 1624). RESULTS: A higher proportion of patients in the irregular Z-line group were female (26.3%) than in the BE group (14.8% female BE) (P <. 001). A lower proportion of patients in the irregular Z-line group were smokers (33.5%) than in the BE group (52.6% smokers). None of the patients with irregular Z line developed HGD or EAC during a median follow-up period of 4.8 years (interquartile range, 3.2-8.3 years). All 71 incident cases of HGD or EAC developed in patients with BE of >= 1 cm in length. On multivariate analysis, patients with irregular Z line and patients with BE of >= 1 cm did not differ significantly in age, race, or duration of follow-up. CONCLUSIONS: In a prospective, multicenter cohort study, we found that patients with irregular Z line do not develop HGD or esophageal cancer within 5 years after index endoscopy.