Progression of specialized intestinal metaplasia at the cardia to macroscopically evident Barrett's esophagus: an entity of concern in the ProGERD study

Abstract

Objectives and aims. Histological Barrett's esophagus, defined as specialized intestinal metaplasia (SIM+) at the cardia without endoscopic suspicion of columnar epithelium, is found frequently in biopsies at the gastro-esophageal junction although its clinical relevance is unknown. The authors aim was to evaluate prospectively the progression of SIM+ to macroscopically evident Barrett's esophagus (BE/SIM+), and to identify risk factors for this progression. Methods. Data were obtained from a sub-group of patients (no visible BE at presentation, but SIM+) included in the ProGERD study, a prospective evaluation of the clinical course of GERD under routine clinical care. They had esomeprazole 20–40 mg/day for 2–8 weeks. Symptom assessment was performed annually, and endoscopy with biopsy was planned at baseline, after healing treatment and after 2 and/or 5 years. Results. 128 of 171 (74.8%) patients with unequivocal SIM at the z-line after healing were biopsied again after 2 and/or 5 years. At follow-up, 33 (25.8%) of these patients showed progression to BE/SIM+. Factors significantly associated with progression were smoking, a long history of GERD and severe esophagitis at baseline. Patients who had progressed to BE/SIM+ already at 2 years showed consistent findings at 5 years. Conclusion. More than 20% of GERD patients with SIM+ in this study were found to have BE/SIM+ within 2–5 years. This finding supports the hypothesis that SIM+ at the cardia could be the missing link explaining increased cancer risk in GERD patients without overt BE and merits further investigation in a prospective study.

Key Words::

• Barrett's esophagus
• GERD
• specialized intestinal metaplasia

Acknowledgement

This study was supported by AstraZeneca R&D, Mölndal, Sweden. Writing assistance was provided by Dr Madeline Frame and funded by AstraZeneca.

Declaration of interest: Joachim Labenz accepts full responsibility for the conduct of the study and had access to the data. Tore Lind and Kai Richter are employees of AstraZeneca. The study was funded by AstraZeneca, Wedel, Germany, but run independently by the steering committee, with data analyses performed at an academic institution.