AGA Abstracts Table 1 Sa1253 Incidence Rate and Predictors of Progression in Patients' With Barrett's Esophagus: Experience From a Large Irish Tertiary Centre Grace Chan, Jun Liong Chin, Marie O' Brien, Cian Muldoon, Ravi Narayanasamy, John Reynolds, Dermot O'Toole Background: Low- (LGD) and high-grade dysplasia (HGD) are known risk precursor for the development of esophageal adenocarcinoma (EAC) in Barrett's esophagus (BE). The significance of indefinite for dysplasia (IND) on histology is poorly characterised with limited data on risk of progression. Aims: To identify the incidence and rate of progression of BE- IND to LGD, HGD and EAC, in a large homogeneous cohort of patients followed in a dedicated BE programme. We also assessed the predictors of progression for patients diagnosed with BE-IND. Methods: Data was extracted from a prospective electronic patient record cohort in our Barrett's registry. Patients diagnosed with BE-IND at diagnosis or follow-up since January 2006 were included (patients with previous grade >IND were excluded). All pathol- ogy specimens (Vienna classification) were reviewed by two expert GI pathologists. Following a diagnosis of BE-IND, twice daily proton-pump inhibitors were prescribed with surveillance endoscopy performed between 6 to 12 months by senior endoscopists (using NBI, FICE and quadrantic biopsies every 1cm). Results: 110 of 1383 patients (8%) were diagnosed with BE-IND (49 at initial endoscopy and 61 patients developed IND during the surveillance period) with a mean age of 63.1 ±11.4 years (70% were males with a mean BMI of 28.8 ±5.9kg/m 2 ). The mean follow-up duration was 70.8 ±63.4months. The incidence rate for development of BE-IND in patients who initially had non-dysplastic BE was 9 new cases per 1000 persons/year. Over this period, 31 (28.2%) patients progressed from BE-IND: 24 (21.8%) to LGD; 1 (0.9%) to HGD and 6 (5.5%) to EAC (2 with carcinoma in-situ, 2 intramucosal carcinoma and 2 submucosal invasion). The progression rates to LGD, HGD and EAC were 2.5, 0.1 and 0.6 per 100 person/years, respectively. Higher BMI (30.9kg/m 2 for progressors vs 27.5 kg/m 2 for non-progressors, p=0.022) was associated with significant risk of progression of IND. Age, gender, smoking history, alcohol consumption and length of BE did not significantly increase the risk of IND progression in this cohort. Conclusion: In our single center homogeneous cohort of BE, the incidence of IND and rates of progression to LGD/HGD/EAC were similar to other reports in the literature. Higher BMI was found to be a predictor of progression and should be targeted in risk stratification in surveillance and management of BE. Sa1254 The Extent of Barrett's Esophagus Predicts Resistance to Successful Endoscopic Eradication Therapy for Barrett's Esophagus (BE) With Dysplasia or Early Cancer (EAC): Results From an International, Multi-Center Consortium Sreekar Vennelaganti, Stefan Seewald, Prashanth Vennalaganti, Hye Yeon Jhun, Jesica Brown, Benjamin Alsop, Ajay Bansal, Alessandro Repici, Neil Gupta, Gary W. Falk, Irving Waxman, Vani J. Konda, Rehan Haidry, Andrew S. Ross, Daniel Buckles, Sharad Mathur, Mojtaba S. Olyaee, Prateek Sharma Background: Understanding factors that predict resistance to successful endoscopic eradica- tion therapy (EET) in neoplastic BE patients are critical to improve response to therapy. Our aim was to determine the resistance rates and predictors of resistance of BE with dysplasia to EET in an international, multi-center cohort of neoplastic BE patients undergoing EET. Methods: This is a multi-center outcomes project of a large cohort of neoplastic BE patients being treated with EET. Patients who underwent EET with either EMR only or hybrid therapy (EMR+RFA) were included in this analysis. Patients who discontinued EET, started surveillance prior to CE-IM, and those still undergoing treatment were excluded. Complete eradication of intestinal metaplasia (CE-IM) was defined as having an endoscopy with no visible columnar lined epithelium in the tubular esophagus and biopsies of the neo- squamous mucosa showing no intestinal metaplasia. Patients were considered to be resistant to EET if they have not achieved CE-IM with 4 or more EET sessions. Patients who had not yet achieved CE-IM and had not received at least 4 EET sessions were considered to be still undergoing therapy. Patient demographics, BE extent (using Prague C&M criteria), presence of hiatus hernia, and PPI use were recorded. To account for possible confounding variables, a propensity logistic regression model was used (SAS 9.4 (Cary, NC)). Results: Of 374 BE patients, 152 were eligible for analysis (mean age 65.2; 90% males; 92% Cauca- sians). The median C and M extents were 2.0 and 5.0 cm respectively. Overall 14 % patients met definition for ‘resistance' to EET. When C and M extents were used as continuous variables, for every 1 cm increase in C and M extents, there was significantly greater chance of BE segment being resistant to EET (OR:1.31(1.13, 1.53) p<.001) and OR:1.33 (1.14, 1.56 p<.001 for M and C extents respectively). In addition, C >6 and M>8 extents were separately evaluated. 27.8% patients had C ≥6 cm [median C length 8 cm IQR(8-10.5)], and were more likely to be resistant to EET compared to those with C<6cm (40.6% vs. 6.0%, p<0.001). 26.8% patients had M ≥8 cm [median M length 10 cm IQR (9-11)] and patients with M≥8 cm were more likely to be resistant to EET compared to those with an M<8cm (34.2% vs. 6.7%, p<.001). After adjusting for age, gender, HH, race, use of PPI, and baseline histology, C≥6cm (OR: 7.96 (2.29, 27.74)p<.001) and M≥8cm (OR:6.36(2.13, 18.97),p=.001) independently predicted resistance to EET in achieving CE-IM. Conclusions: S-258 AGA Abstracts Results of this multi-center outcomes data show that the pre-treatment Barrett's esophagus extent (both C and M) determine resistance to endoscopic therapy in achieving CE-IM. For every 1 cm increase in the extent of both the circumferential and maximal extent, there is an approximately 30% increase in chance of being resistant to EET. Sa1255 Low Risk of Neoplastic Progression of Barrett's Esophagus in Women: Results From a Large Multi-Center Consortium Sreekar Vennelaganti, Prashanth Vennalaganti, Srinivas Gaddam, Patrick E. Young, Neil Gupta, Prashanthi N. Thota, Brooks D. Cash, Sharad Mathur, Richard Sampliner, Fouad J. Moawad, David Lieberman, Ajay Bansal, Kevin Kennedy, John J. Vargo, Gary W. Falk, Prateek Sharma Background and Aim: Although men are at a higher risk for both Barrett's esophagus and esophageal adenocarcinoma (EAC), the natural history and progression rates of BE to dysplasia and EAC has not been well studied in women. Methods: This is a multicenter outcomes project (5 centers) of a large cohort of prospectively followed BE patients. BE was defined by columnar metaplasia in the tubular esophagus on endoscopy and intestinal metaplasia on biopsy. Neoplasia was graded as low-grade dysplasia (LGD), high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Duration of follow up was calculated from time of BE diagnosis to most recent endoscopy with biopsy. Patients with non-dysplastic BE (NDBE) on first EGD and with at least 1 year of subsequent endoscopic follow up were included. Patients with visible lesion, dysplasia and EAC developing within 1-year of BE diagnosis were considered to be prevalent cases. Progression rates between women and men were compared using chi-square and Student's t-test. Multivariable logistic regression was used to assess the association between gender and progression after adjusting for possible con- founding variables. Results: Of the total 4263 number of patients in the cohort, 2146 patients met the inclusion criteria. These included 324 women [mean age 58 (SD 15) years, Caucasians 83%, median BE length 3.1 cm (SD 3.1)] and 1821 men [mean age 56 (SD 18) years, Caucasians 87%, median BE length 3.6 cm (SD 3.2)]. The overall median duration of follow up in the entire cohort was 5.7 years; with no significant difference in follow up between women and men (6.3 vs. 5.7 years, p = 0.95). During follow up, there were a total of 34 (1.6%) incident EACs with an overall annual incidence rate of 0.3% (95% CI: 0.2- 0.4). The annual incidence rates of EAC (0.05% vs 0.3%; p=0.04) and for a combined end point of HGD/cancer (0.1% vs. 1.1%, p <0.001) were significantly lower among women compared to men. Female gender remained an independent predictor for progression to HGD/EAC when rates were adjusted to BMI, smoking history, race, aspirin, NSAID, PPI and statin use, hypertriglyceridemia, BE length and baseline histology (OR 0.11; 95% CI: 0.03 - 0.45; p=0 .002). Conclusions: Results from this multi-center outcomes study demonstrate a significantly lower risk of both cancer and HGD/cancer in women as compare to men. The extremely low risk of esophageal adenocarcinoma in women (0.05% per year) with BE questions the role of surveillance endoscopy in this sub-group of BE patients. Sa1256 Surveillance of Barrett's Esophagus Post Ablation: Is It Better to Use Jumbo Over Standard Biopsy Forceps? Sreekar Vennelaganti, Prashanth Vennalaganti, Abhiram Duvvuri, Diego Lim, Bhairvi Jani, Alessandro Repici, Camilla Ciscato, Paola Spaggiari, Pierluigi Consolo, Milena Di Leo, Sharad Mathur, Jaime Porter, Elisa Ferrara, Kevin Kennedy, Neil Gupta, Prateek Sharma Background: Obtaining adequate tissue on biopsy is critical for the detection of sub- squamous intestinal metaplasia/dysplasia in patients undergoing surveillance after endoscopic eradication therapy for dysplastic Barrett ′s esophagus (BE). Aims: To compare the adequacy of biopsy specimens obtained from neo-squamous mucosa post radiofrequency ablation (RFA) using jumbo vs. standard biopsy forceps. Methods: Two-center study of patients undergoing RFA ablation of dysplastic BE; each center (as their routine practice) using either jumbo (Boston Scientific, Radial Jaw 4) or standard (Boston, Scientific Radial Jaw 3) biopsy forceps. After endoscopic eradication of all columnar lined epithelium, jumbo or standard biopsy forceps were utilized to obtain surveillance biopsies from the neo squamous epithe- lium. Patient demographics were noted. Two experienced GI pathologists reviewed slides in a blinded fashion using previously published criteria to assess tissue depth. Findings were entered in a case report form (CRF) which recorded the following: presence of lamina propria and proportion of squamous epithelium with partial or full thickness lamina propria. Squamous epithelial biopsies that contained >2/3 lamina propria was considered as ‘adequate'. Biopsies with >2/3 tangential orientation were considered poor biopsy specimens. In addition, variables were summarized using mean, median values along with interquartile range. Fre- quencies and percentages were reported for categorical variables. Results: A total of 211 biopsies from 55 BE patients, who had undergone RFA therapy, were identified from a prospectively maintained database and reviewed. 145 biopsies (29 patients, 20 males, mean age 61 years, IQR 33 - 83) obtained using jumbo forceps were compared to 66 biopsies (26 patients, all males, mean age 65 years, IQR 56 - 76) using standard forceps biopsies (Table). Proportion of specimens with any sub-epithelial lamina propria were similar using jumbo and standard forceps (51.7% vs. 53%, p = 0.860). Adequate sub-epithelial lamina propria (biopsies containing > 2/3 of lamina propria) were low but similar using either jumbo or standard biopsies (17.9% vs. 9.1%, p = 0.096). Conclusions: Similar to previously published data, we confirm that the proportion of biopsy specimens, from the neo squamous mucosa, with adequate lamina propria is low. However, there were no significant differences between the samples obtained with jumbo versus standard biopsy forceps; approximately half of the specimens with either forceps had any lamina propria. Jumbo forceps appear to have no added advantage over standard forceps to obtain adequate biopsy specimens from the neo squamous mucosa post ablation. Table: Comparison of proportion of specimens with any degree of sub-epithelial lamina propria in biopsy specimen between jumbo and standard forceps