Incidence of Adenocarcinoma of the Gastric Cardia Is Similar to That of Adenocarcinoma in the Esophagus After Successful Radiofrequency Ablation in Barrettʼs Esophagus

Abstract

Introduction: Radiofrequency ablation (RFA) is an effective treatment for Barrett's Esophagus (BE) that results in high rates of complete eradication of intestinal metaplasia (CEIM). Despite RFA, progression to adenocarcinoma may occur, in either the tubular esophagus or the gastric cardia. We sought to describe the rate and timing of gastric cardia adenocarcinoma after RFA for BE. Methods: The U.S. RFA Registry is a national, prospective study of patients with Barrett's Esophagus (BE) treated with RFA at 148 institutions (113 community-based, 35 academic-affiliated). We included patients without prevalent adenocarcinoma. We estimated the incidence rate of gastric cardia adenocarcinoma overall and stratified by CEIM status with profile-likelihood confidence limits (CL). We performed inverse probability of sampling weighting to estimate incidence rates of cardia adenocarcinoma among patients with cardia sampling under a scenario of universal sampling. We estimated unadjusted and adjusted rate ratios for cardia adenocarcinoma among the full population and among the standardized, sampled population. Results: Of 5,521 patients in the registry, 5,085 without prevalent adenocarcinoma were included for analysis. Baseline characteristics are described in table 1. There were 21 incident cases of cardia adenocarcinoma, of which 13 occurred before or at the time of esophageal CEIM and 8 occurred during surveillance. In the full population, the overall incidence of cardia adenocarcinoma was 1.49 per 1,000 person-years (95% CL: 0.94 - 2.22), prior to CEIM was 2.23 (95% CL: 1.23 - 3.68), and after CEIM was 0.97 (95% CL: 0.45 - 1.81). In the sampled, standardized population the overall incidence of cardia adenocarcinoma was 3.03 per 1,000 person-years (95% CL: 2.02 - 4.34), prior to CEIM was 5.89 (95% CL: 3.54 - 9.11), and after CEIM was 1.58 (95% CL: 0.76 - 2.85). Incidence of cardia adenocarcinoma was much less than incidence of esophageal adenocarcinoma before CEIM (13.4 per 1,000 person-years) but similar to after CEIM (2.60 per 1,000 person-years). Conclusion: Cardia adenocarcinoma incidence is similar to esophageal adenocarcinoma incidence after successful RFA. Both cardia and esophageal adenocarcinoma are strongly associated with baseline histologic grade and less common after CEIM. Nearly half of U.S. RFA registry patients never had pathologic examination of the cardia, suggesting that neoplasia may be missed without routine sampling of the cardia.Table 1: Baseline clinical and endoscopic characteristics of 5,085 patients in the U.S. RFA registry dataset, 2,327 patients with cardia sampling, and the inverse probability of sampling weighted pseudo-populationTable 2: Unadjusted and adjusted rate ratios for the incidence of gastric cardia adenocarcinoma among U.S. RFA registry patients and the standardized population with cardia samplingFigure 1