Sa1529 Radiofrequency Ablation +/- Endoscopic Resection for Barrett's Esophagus With High-Grade Dysplasia and/or Early Cancer: Durability of the Post-Treatment Neosquamous Epithelium At 5-Year Follow-Up

Radiofrequency Ablation /Endoscopic Resection for Barrett’s Esophagus With High-Grade Dysplasia and/or Early Cancer: Durability of the Post-Treatment Neosquamous Epithelium At 5-Year Follow-Up Kai Yi N. Phoa, Roos E. Pouw, Frederike G. Van Vilsteren, Carine Sondermeijer, Lorenza Alvarez Herrero, Fiebo J. Ten Kate, Mike Visser, Mark I. Van Berge Henegouwen, Bas L. Weusten, Rosalie C. Mallant-Hent, Jacques J. Bergman Gastroenterology, Academic Medical Center, Amsterdam, Netherlands; Gastroenterology, St Antonius hospital, Nieuwegein, Netherlands; Pathology, Academic Medical Center, Amsterdam, Netherlands; Surgery, Academic Medical Center, Amsterdam, Netherlands; Gastroenterology, Flevoziekenhuis, Almere, Netherlands Background: Radiofrequency ablation (RFA) is safe and effective for complete eradication of Barrett’s esophagus (BE) with high-grade dysplasia (HGD) and/or early cancer (EC), and may be safely preceded by focal endoscopic resection (ER) to remove visible lesions. Less is known regarding the long-term (5-year) durability of the neosquamous epithelium (NSE) that repopulates the esophagus after RFA. Aim: In a prospective cohort of BE patients with HGD/EC, all of whom achieved complete epithelial reversion after RFA /focal ER at 1-year follow-up, we assessed the 5-year durability of the treatment response. Methods: At study entry, patients had BE 10cm with HGD or EC( T1sm1) confirmed by an expert pathologist. We removed visible lesions with focal ER, followed by repeat biopsy to establish the post-ER diagnosis. We performed RFA at 2-month intervals until all Barrett’s mucosa was visibly eradicated. Annually thereafter we performed high-resolution endoscopy with NBI, taking biopsies (4Q/2cm) from the NSE above the top of the gastric folds. Additionally, biopsies were obtained distal to the neosquamocolumnar junction (gastric cardia, analyzed separately). During and after treatment patients received high-dose PPI maintenance medication. Primary outcomes: 1) complete histological remission of HGD/EC (CR-neo), 2) complete histological remission of intestinal metaplasia (CR-IM) in esophageal biopsies. Secondary outcome: presence of IM in biopsies from the gastric cardia. Results: Twenty-three patients were analyzed (17 men, mean age 63.4, median BE C4M7). Entry ER was performed in 13 patients for lesions showing: EC (n 4), HGD (n 6) or LGD (n 3). Worst grade post-ER (pre-RFA): HGD(n 20), LGD(n 3). All patients achieved CR-neo/CR-IM at 1-year (2 required focal escape ER). Three patients exited the study at 16, 28 and 44 mo due to unrelated comorbidity. All were CR-neo/CR-IM at last follow-up. Median follow-up (n 23) since study entry was 52 mo (IQR 44-55). Follow-up endoscopy with biopsies was performed a median of 5 (IQR 4-5) times per patient (mean 77 38 biopsies per pt (61 NSE, 17 cardia)). All patients (n 23, 100%) demonstrated sustained CR-neo and CR-IM at every biopsy session during follow-up. None of the 1780 NSE biopsies demonstrated subsquamous IM. In 37 of the 379 gastric cardia biopsies (9 pts) focal non-dysplastic IM was detected (not treated). Conclusion: We have previously reported that RFA /focal ER for BE with HGD and/or EC is safe and effective, resulting in 100% CR-neo and CRIM at 1-year. The results of the present long-term follow-up of this cohort suggest that the histologically normal NSE achieved after treatment at 1-year is further durable at 5-year follow-up. No patient in this cohort developed invasive cancer or sustained BE-related morbidity. The clinical relevance of focal IM in a normal appearing cardia remains unknown.