OC-051 Patients Undergoing Radiofrequency Ablation (Rfa) for Barrett’S Related Neoplasia have Improved outcomes with Decreasing Lenghths of Baseline Barrett’S Oesophagus (Be) & Increasing Number of RFA Sessions

Introduction BE is the pre-cursor to oesophageal adenocarcinoma (OAC). High grade dysplasia (HGD) & early mucosal neoplasia in BE have a 40–60% risk of progressing to OAC. Endoscopic mucosal resection (EMR) & RFA are alternatives to surgery for curative treatment of these patients. We present prospective data from 19 centres in the UK HALO RFA registry. Methods Before RFA, superficial lesions were removed by EMR. Patients then underwent RFA 3 monthly until all BE was ablated or cancer developed (endpoints). Biopsies were taken at 12 months for Primary outcomes (clearance for HGD (CR-HGD), all dysplasia (CR-D) & BE (CR-BE)). Results 630 patients have outcomes recorded. We report on 370 who have completed treatment. 81% male, mean age 68 years (40–91). Patient’s underwent mean 2.5 ablations (1–6) during protocol. 70% baseline histology HGD, 27% IMC & 3% LGD. Mean length baseline BE 5.6cm (1–20). At 12 months CR-HGD was 87% patients, CR-D 82%, & CR-BE 64%. 97% with no dysplasia at 12 months remain disease free at most recent follow up (median 18 months,range 2–68). Kaplan Meier statistics predict CR-D is durable at 5 years with 88% remaining disease free. Logistic regression demonstrate each extra 1 cm of BE reduces chances of attaining CR-D by 15.7% (OR 1.156, SE 0.048, CI 1.07–1.26, p = 0.0003) & for each extra RFA treatment likelihood of CR-D increases by 31.7% (OR = 0.683, SE 0.95, CI 0.52–0.89, p = 0.0006). Progression to invasive cancer at 12 months is 2.7%. Symptomatic strictures requiring dilatation occurred in 9% after treatment. Conclusion End of protocol CR-D is encouraging at 83% & successful eradication appears durable. Patients with shorter segment BE respond better & multiple treatments are more likely to achieve CR-D. Our data represent real life outcomes of integrating novel endotherapy into demanding endoscopy service commitments Disclosure of Interest None Declared