547. DISEASE SPECIFIC MORTALITY OF EARLY-STAGE ESOPHAGEAL NEOPLASIA IN BARRETT’S ESOPHAGUS TREATED WITH ENDOSCOPIC THERAPY

Abstract Background High-grade dysplasia (HGD) and intramucosal (T1a) esophageal adenocarcinoma (EAC) are indication for endoscopic eradication therapy (EET) with endoscopic resection (ER) and/or radiofrequency ablation (RFA). The goal of the endoscopic therapy is to prevent progression to advanced EAC and cure the underlying Barrett’s esophagus (BE) when present. Previous studies have showed high rate of success of EET in short term, however little is known about long term results of EET. We aimed to evaluate long-term outcome of EET with particular reference to disease specific mortality and progression to major surgery. Methods We conducted a single center retrospective study including patients who underwent EET for HGD and T1a EAC January 2005-December 2022. We excluded patients with gastric disease and evidence of T1b EAC at baseline ER. Primary outcomes assessed disease specific mortality (DSM) of esophageal cancer in this longitudinal cohort, which is defined as death within 12 months of progression to advanced cancer. Secondary outcomes evaluate endoscopic recurrence, progression to esophagectomy, post-procedure complications and 5-year overall survival. Results 299 patients were included in this study. 252 were treated with a combination of ER and RFA, whereas 47 only received primary RFA. Median number of EET sessions in both patient groups is 4(p=0.48). Patients with HGD were more likely to be detected on surveillance compared to those with T1a EAC (p=0.004). We demonstrate a DSM rate of 2.7%(n=8), with a 5-year overall survival of 74.6%(n=223). 5.7%(n=17) of patients sustained severe post-procedure complications (Clavien-Dindo>3). Endoscopic recurrence occurred in 18.7%(n=56) and 6.7%(n=20) developed disease progression that required surgical intervention. Baseline T1a was associated with higher rates of esophagectomy compared to HGD (p=0.0135). Conclusion EET is a safe and effective treatment for patients with early-stage esophageal neoplasia. In comparison to esophago-gastric surgery, EET offers excellent results with a significantly lower morbidity and mortality risk. However, it is resource intensive as patients often require multiple treatments with long-term, routine surveillance. Patients also require strict compliance to maximize therapeutic outcomes and prevent recurrence or progression. Further studies are required to improve risk-stratification in this cohort and determine the optimal surveillance strategy post EET.