Background: Esophageal adenocarcinoma (EAC) diagnosis involves invasive and expensive endoscopy with biopsy, but rising EAC incidence has not been reduced by increased surveillance. This study aimed to develop and clinically validate a novel glycoprotein biomarker blood test for EAC, named PromarkerEso. Methods: Serum glycoprotein relative concentrations were measured using a lectin-based magnetic bead array pulldown method, with multiple reaction monitoring mass spectrometry in 259 samples across three independent cohorts. A panel of glycoproteins: alpha-1-antitrypsin, alpha-1-antichymotrypsin, complement C9 and plasma kallikrein, were combined with clinical factors (age, sex and BMI) in an algorithm to categorize the samples by the risk of EAC. Results: PromarkerEso demonstrated a strong discrimination of EAC from the controls (area under the curve (AUC) of 0.91 in the development cohort and 0.82 and 0.98 in the validation cohorts). The test exhibited a high sensitivity for EAC (98% in the development cohort, and 99.9% and 91% in the validation cohorts) and a high specificity (88% in the development cohort, and 86% and 99% in the validation cohorts). PromarkerEso identified individuals with and without EAC (96% and 95% positive and negative predictive values). Conclusions: This less invasive approach for EAC detection with the novel combination of these glycoprotein biomarkers and clinical factors coalesces in a potential step toward improved diagnosis.

BACKGROUND AND AIMS:Liquid nitrogen spray cryotherapy (SCT) is an alternative to radiofrequency ablation (RFA) for eradication of dysplastic Barrett's esophagus (BE). We aimed to assess the safety, efficacy, and durability of SCT in a multicenter U.S. registry. METHODS:This is a multicenter prospective registry of adults with BE treated with truFreeze Spray Cryotherapy (Steris, Mentor, Ohio, USA) (4 community and 11 academic sites, 2013-2022). Complete eradication of intestinal metaplasia (CEIM) and dysplasia (CED) were assessed in BE with dysplasia or intramucosal adenocarcinoma. Kaplan-Meier analysis of CEIM and CED was performed. Hazard ratios for CEIM stratified by baseline risk factors were calculated. RESULTS:Among 138 subjects with low-grade dysplasia (24%), high-grade dysplasia (49%), and intramucosal adenocarcinoma (27%), 34% received prior RFA therapy. Subjects received a median of 2 SCT sessions. Adverse events were uncommon, with 5.5% reporting strictures and 0.7% a perforation. Rates of CEIM and CED, respectively, were 66% and 84% after 2 years and 67% and 92% after 3 years. In RFA-naïve patients, CEIM was 77% and CED was 96% at 3 years. Increasing BE length (per centimeter: adjusted hazard ratio, 0.90; 95% confidence interval, 0.83-0.96) and prior treatment with RFA (adjusted hazard ratio, 0.39; 95% confidence interval, 0.22-0.69) were associated with a lower rate of CEIM. Recurrence occurred in 8.8% (n = 6) at a mean follow-up of 2.5 years after CEIM. CONCLUSION:In this largest reported prospective cohort, liquid nitrogen SCT was safe and effective for the treatment of dysplastic and neoplastic BE. Response was lower in those with prior failed RFA; in that cohort, approximately 50% attained CEIM at 3 years.

Johns Hopkins University, USA; Northwell Health, USA; Methodist Dallas Medical Center, USA; Medical University of South Carolina, USA; Memorial Hermann Health System, USA; Geisinger Medical Center, USA; VA North Texas Health Care System, USA; LSU Health New Orleans, USA.

Background and Aims: Patients with primary sclerosing cholangitis (PSC) and dominant biliary strictures carry increased risk for the development of cholangiocarcinoma. Although ERCP-based techniques including brush cytology and intraductal biopsy sampling represent first-line tissue sampling methods for dominant strictures, sensitivity is low. Probe-based confocal laser endomicroscopy (pCLE) offers microscopic-level imaging of subepithelial biliary mucosa. Because data regarding the use of pCLE in PSC are limited, we aimed to investigate its diagnostic performance in dominant strictures. Methods: This was a multicenter prospective study involving PSC patients with dominant strictures. ERCP with pCLE was performed with use of the Miami classification (2+ criteria for malignant diagnosis) and Paris classification. Final malignant diagnoses required histopathologic confirmation, and benign diagnoses required a minimum of 1 year of follow-up without development of cancer. Results: Fifty-nine patients (mean age, 49 years; 59% men) with 63 strictures were included in the study. Stricture locations included the common bile duct (31.7%), bifurcation (22.2%), and common hepatic duct (19%). Seven patients (11.9%) were found to have cholangiocarcinoma. The sensitivity and specificity of pCLE was 85.7% (95% confidence interval [CI], 42.1-99.6) and 73.1% (95% CI, 58.9-84.4), respectively. Within specific stricture locations, the highest sensitivity was seen at the bifurcation (100%; 95% CI, 2.5-100) and the right hepatic duct (100%; 95% CI, 29.2-100). The lowest sensitivities were seen at the common bile duct (25%; 95% CI, 5.5-57.2) and the left hepatic duct (28.6%; 95% CI, 3.7-70.9). Conclusions: In this prospective multicenter study, pCLE had a high sensitivity in detecting cholangiocarcinoma, but technical aspects of the probe may limit evaluation in the common bile duct and left hepatic duct. Further evaluation is needed to elucidate the role of pCLE in the algorithm of excluding neoplasia in biliary strictures associated with PSC.

Background and Objectives: No single optimal test reliably determines the pancreatic cyst subtype. Following EUS-FNA, the “string sign” test can differentiate mucinous from nonmucinous cysts. However, the interobserver variability of string sign results has not been studied. Methods: An experienced endosonographer performed EUS-FNA of pancreatic cysts on different patients and was recorded on video performing the string sign test for each. The videos were shared internationally with 14 experienced endosonographers, with a survey for each video: “Is the string sign positive?” and “If the string sign is positive, what is the length of the formed string?” Also asked “What is the cutoff length for string sign to be considered positive?” Interobserver variability was assessed using the kappa statistic (κ). Results: A total of 112 observations were collected from 14 endosonographers. Regarding string sign test positivity, κ was 0.6 among 14 observers indicating good interrater agreement (P < 0.001) while κ was 0.38 when observers were compared to the index endosonographer demonstrating marginal agreement (P < 0.001). Among observations of the length of the string in positive samples, 89.8% showed >5 mm of variability (P < 0.001), indicating marked variability. There was poor agreement on the cutoff length for a string to be considered positive. Conclusion: String sign of pancreatic cysts has a good interobserver agreement regarding its positivity that can help in differentiating mucinous from nonmucinous pancreatic cysts. However, the agreement is poor on the measured length of the string and the cutoff length of the formed string to be considered a positive string sign.

Background and study aims First-generation optical coherence tomography (OCT) has been shown to increase diagnostic sensitivity for malignant biliary and pancreatic-duct strictures. A newer OCT imaging system, NVision Volumetric Laser Endomicroscopy (VLE), allows for in vivo cross-sectional imaging of the ductal wall at the microstructure level during endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to identify and evaluate characteristics on OCT that are predictive of benign and malignant strictures. Patients and methods Consecutive patients from six centers who underwent OCT between September 2016 and September 2017 were included in a dedicated registry. OCT images were analyzed, and nine recurring characteristics were further assessed. Final diagnosis was based on histology and/or surgical pathology. Results 86 patients were included (49 % male, mean age 64.7). OCT was performed in the bile duct in 79 patients and the pancreatic duct in seven. Nine OCT characteristics were identified: dilated hypo-reflective structures (n = 7), onion-skin layering (n = 8), intact layering (n = 17), layering effacement (n = 25), scalloping (n = 20), thickened epithelium (n = 42), hyper-glandular mucosa (n = 13), prominent blood vessels (n = 6), and a hyper-reflective surface (n = 20). Presence of hyper-glandular mucosa, hyper-reflective surface and scalloping significantly increased the odds of malignancy diagnosis by 6 times more (P = 0.0203; 95 % CI 1.3 to 26.5), 4.7 times more (P = 0.0255; 95 % CI 1.2 to 18.0) and 7.9 times more (P = 0.0035; 95 % CI 1.97 to 31.8) respectively. Conclusion By providing in-vivo cross-sectional imaging of the pancreatic and biliary duct wall, OCT technology may improve sensitivity in diagnosing malignant strictures and provide standardizable criteria predictive of malignancy.

Detection of cholangiocarcinoma (CCA) in primary sclerosing cholangitis (PSC) is difficult. ERCP with brush cytology and fluoroscopy-guided biopsy have low sensitivity. Probe-based confocal laser endomicroscopy (pCLE) offers imaging of subepithelial structures and may increase the ability to detect malignancy.

The EsophaCap™ DNA methylation biomarker validation study by Wang, Kambhampati and colleagues (1) follows a spade of reports (summarized in Table 1 ) aiming to develop screening tests for Barrett’s esophagus (BE). BE is a non-malignant metaplastic condition with little or no clinical symptoms. Arguably, the main importance of diagnosing BE is the increased risk of the patient to progress to esophageal adenocarcinoma (EAC).

Liquid nitrogen spray cryotherapy (SCT) has been shown to be safe and effective in achieving complete eradication of intestinal metaplasia (CEIM) in Barrett's esophagus (BE). However, rates of recurrence after successful CEIM in registry patients are incompletely described.

BACKGROUND & AIMS Esophageal adenocarcinoma (EAC) is thought to develop from asymptomatic Barrett’s esophagus (BE) with a low annual rate of conversion. Current endoscopy surveillance for BE patients is probably not cost-effective. Previously, we discovered serum glycoprotein biomarker candidates which could discriminate BE patients from EAC. Here, we aimed to validate candidate serum glycoprotein biomarkers in independent cohorts, and to develop a biomarker panel for BE surveillance. METHODS Serum glycoprotein biomarker candidates were measured in 301 serum samples collected from Australia (4 states) and USA (1 clinic) using lectin magnetic bead array (LeMBA) coupled multiple reaction monitoring mass spectrometry (MRM-MS). The area under receiver operating characteristic curve was calculated as a measure of discrimination, and multivariate recursive partitioning was used to formulate a multi-marker panel for BE surveillance. RESULTS Different glycoforms of complement C9 (C9), gelsolin (GSN), serum paraoxonase/arylesterase 1 (PON1) and serum paraoxonase/lactonase 3 (PON3) were validated as diagnostic glycoprotein biomarker candidates for EAC across both cohorts. A panel of 10 serum glycoproteins accurately discriminated BE patients not requiring intervention [BE+/-low grade dysplasia] from those requiring intervention [BE with high grade dysplasia (BE-HGD) or EAC]. Tissue expression of C9 was found to be induced in BE, dysplastic BE and EAC. In longitudinal samples from subjects that have progressed towards EAC, levels of serum C9 glycoforms were increased with disease progression. CONCLUSIONS Further prospective clinical validation of the confirmed biomarker candidates in a large cohort is warranted. A first-line BE surveillance blood test may be developed based on these findings. AAL : Aleuria aurantia lectin %CV : % Co-efficient of variation AUROC : Area under receiver operating characteristics curve BE : Barrett’s esophagus BE-HGD : Barrett’s esophagus with high-grade dysplasia BE-ID : Barrett’s esophagus which is indefinite for dysplasia BE-LGD : Barrett’s esophagus with low-grade dysplasia BMI : Body mass index C1QB : Complement C1q subcomponent subunit B C2 : Complement C2 C3 : Complement C3 C4B : Complement C4-B C4BPA : C4b-binding protein alpha chain C4BPB : C4b-binding protein beta chain C9 : Complement component C9 CFB : Complement factor B CFI : Complement factor I CI : Confidence interval CP : Ceruloplasmin EAC : Esophageal adenocarcinoma EPHA : Erythroagglutinin from Phaseolus vulgaris FFPE : Formalin-fixed, paraffin-embedded GERD : Gastroesophageal reflux disease GSN : Gelsolin JAC : Jacalin from Artocarpus integrifolia LeMBA : Lectin magnetic bead array MRM-MS : Multiple reaction monitoring-mass spectrometry NPL : Narcissus pseudonarcissus lectin NSE : Non-specialized epithelium OR : Odds ratio PGLYRP2 : N-acetylmuramoyl-L-alanine amidase PON1 : Serum paraoxonase/arylesterase 1 PON3 : Serum paraoxonase/lactonase 3 RBP4 : Retinol-binding protein 4 SERPINA4 : Kallistatin SIS : Stable isotope-labeled internal standard

Liquid nitrogen spray cryotherapy (LNSCT) is a safe, well-tolerated, and effective therapy for Barrett's esophagus (BE)-associated dysplasia. A recent study with an earlier version of the current device showed effectiveness in treating esophageal cancer (EC) (Dis Esoph 2017; 30:1), but information on the use of LNSCT for palliation of EC is limited. To assess the efficacy of LNSCT in patients (pts) with invasive EC (adenocarcinoma [EAC] or squamous cell carcinoma [SCC]) in a multicenter U.S. registry. This is a multicenter prospective registry of subjects with a diagnosis of invasive EAC or SCC treated with truFreeze LNSCT at 4 community and 11 academic sites in the United States. Outcome measures included adverse events. Among 52 subjects, 43 (82.7%) had EAC and 9 (17.3%) had SCC. Mean age (SD) was 73.2 ± 10.9 years (range 52-90). 44 (84.6%) were male. In pts with EAC, mean BE segment length (SD) was 4.6 ± 3.8 cm. Prior EMR was performed in 19 (36.5%) and ESD in 2 (3.9%) pts. Median follow up was 14.5 months (range 0-49, IQR 8.5-24.5). Median LNSCT treatments was 2.5 (range 1-10, IQR 1-4). Treatment dosimetry ranged from 1-5 cycles per treatment site with spray time of 10-30 seconds. Stricture was noted in 14 (26.9%) pts prior to start of LNSCT. Adverse events included: 1- hematemesis (minor - no transfusion required), 3 – new benign stricture (2 felt possibly related to LNSCT) with dilation in 2. Status at last follow up was: 21 - deceased (9 due to esophageal cancer), 4 - withdrawn, 2 - lost to follow-up, 26 - alive and actively enrolled in study. Kaplan-Meier survival curve is shown below. In a national registry, LNSCT is associated with a low rate of adverse events including stricture development when used for invasive esophageal cancer and is a viable palliative treatment option for this condition.

Esophageal adenocarcinoma (EAC) is thought to develop from asymptomatic Barrett's esophagus (BE) with a low annual rate of conversion. Current endoscopy surveillance of BE patients is probably not cost-effective. Previously, we discovered serum glycoprotein biomarker candidates which could discriminate BE patients from EAC. Here, we aimed to validate candidate serum glycoprotein biomarkers in independent cohorts, and to develop a biomarker candidate panel for BE surveillance. Serum glycoprotein biomarker candidates were measured in 301 serum samples collected from Australia (4 states) and the United States (1 clinic) using previously established lectin magnetic bead array (LeMBA) coupled multiple reaction monitoring mass spectrometry (MRM-MS) tier 3 assay. The area under receiver operating characteristic curve (AUROC) was calculated as a measure of discrimination, and multivariate recursive partitioning was used to formulate a multi-marker panel for BE surveillance. Complement C9 (C9), gelsolin (GSN), serum paraoxonase/arylesterase 1 (PON1) and serum paraoxonase/lactonase 3 (PON3) were validated as diagnostic glycoprotein biomarkers in lectin pull-down samples for EAC across both cohorts. A panel of 10 serum glycoprotein biomarker candidates discriminated BE patients not requiring intervention (BE± low grade dysplasia) from those requiring intervention (BE with high grade dysplasia (BE-HGD) or EAC) with an AUROC value of 0.93. Tissue expression of C9 was found to be induced in BE, dysplastic BE and EAC. In longitudinal samples from subjects that have progressed toward EAC, levels of serum C9 were significantly (p < 0.05) increased with disease progression in EPHA (erythroagglutinin from Phaseolus vulgaris) and NPL (Narcissus pseudonarcissus lectin) pull-down samples. The results confirm alteration of complement pathway glycoproteins during BE-EAC pathogenesis. Further prospective clinical validation of the confirmed biomarker candidates in a large cohort is warranted, prior to development of a first-line BE surveillance blood test.

225 Background: Pancreatic cysts are a group of lesions with malignant potential. Currently, there are no consistently reliable biomarkers or imaging modalities to accurately predict biologic behavior of these cysts. We tested the hypothesis that tumor-derived exosomes (better conserved than free miRNA) can be acquired endoscopically from pancreatic cyst fluid and may allow for improved distinction between benign, premalignant and malignant cysts. Methods: Exosomes were isolated and characterised by differential and buoyant centrifugation from pancreatic cyst fluid obtained from 30 patients with pseudocysts (PS), serous cystic (SC), mucinous cysts (MC), intraductal papillary mucinous neoplasms (IPMN), pancreatitis (PA), and pancreatic cancer (PC) , confirmed with imaging and histology. An Illumina TruSeq Small RNA kit was used to construct a small RNA library, and the libraries were sequenced using the Illumina NextSeq 500 platform. The resulting sequencing FASTQ files were analyzed using miRDeep2 to identify both known and novel miRNAs. Results: Four significant miRNAs which are shared between six of the analyses, specifically hsa-miR-199b-3p, hsa-miR-199a-2-3p, hsa-miR-199a-1-3p and hsa-let-7i-5p were identified. MiRNA hsa-miR-27a-3p was significant and shared between five of the analyses. A total of 15, 12 and 2 significant miRNAs were shared between four, three and two of the analyses, respectively. Importantly, there were a total of 10 significant miRNAs which were unique to each analysis, with the exception of IPMN vs Pseudocyst, and Pancreatic cancer vs Pancreatitis. Specifically these unique miRNAs for each analysis are: hsa-miR-92a-2-3p (Pancreatitis vs Pseudocyst); hsa-miR-92a-1-3p (Serous vs Pseudocyst); hsa-miR-30e-5p (Pancreatic cancer vs Serous), hsa-miR-30b-5p (IPMN vs Pancreatic cancer); and hsa-miR-23b-3p, hsa-miR-99b-5p, hsa-miR-222-3p, hsa-miR-31-5p, hsa-miR-151a-5p, hsa-miR-221-3p (Pancreatic cancer vs. Pseudocyst). Conclusions: Exosomal miRNAs in pancreatic fluid may be used as a biomarker to differentiate between various cyst types and pancreatic cancer. A larger cohort with miRNA quantification and is needed to further validate these findings .

Introduction: Quality improvement and efficiency are principles vital to all providers. Models are appearing that link the provider performance to reimbursements, especially therapeutic endoscopists. It is speculated that majority of procedural delays in large tertiary care hospitals are secondary to physician start time. In contrast, others suggest that non endoscopy time make up the bulk of delays in a procedure suite. We compare our single center performance of efficiency metrics in 2 quarters. Methods: This is a retrospective study that took place from January-June 2017 at Ochsner Health System, Louisiana under IRB approved protocol. We looked at the efficiency metrics of a single advanced therapeutics practitioner in a single therapeutic endoscopy suite at a tertiary care hospital involving inpatient and outpatient endoscopies. Procedures included therapeutic EMR, ESD, therapeutic ERCP, ablative procedures, and therapeutic EUS. All procedures took place under general anesthesia or under monitored anesthesia care. The study was split into 2 quarters: 1st and 2nd. In 2nd quarter, incentives were provided for all staff and physicians to arrive on time, and H&P being completed prior to 7:00 AM. Variables measured: Anesthesia ready time (ART), or time from patient into suite to patient's sedation, endoscopist ready time (ERT), or time from patient's sedation to insertion of scope, procedure time (PT), or time from start to end of procedure,time interval between successive patients (TISP),or time from patient departure from suite until time of arrival of next patient (wheels in to wheels out time), non-endoscopy time (NET), total time (TT), and FIRST, or total minutes before or after official start time. Results: There was no association between start time of physician (FIRST) and TISP in the 1stquarter based on Fisher's Exact Test, p= 0.2835. There was no association between Start time of physician and TISP in the 2nd quarter based on Fisher's Exact Test, p= 0.3848. There was also no association between FIRST and TISP overall based on Fisher's ExactTest, p= 0.3604. The FIRST value was analyzed as early, late, or on time. Conclusion: -Our study showed that FIRST case start time did not significantly influence endoscopy efficiency metrics. Delay in procedural start time was not secondary to physician start time, but instead, other variables. -To further improve current efficiency metrics, a two-team, two-room model is suggested.1131_A Figure 1 No Caption available.1131_B Figure 2 No Caption available.1131_C Figure 3 No Caption available.

Squamous cell carcinoma (SCC) of the pancreas neoplasm that accounts for 0.5-0.7% of all pancreatic cancers and 5% of all pancreatic ductal cancers. Further investigation into risk factors. Early detection and natural history and treatment options is needed. A 66 year-old African American woman with 4 month history of progressive weight loss of 25 pounds associated with abdominal pain radiating to back and recent poorly controlled diabetes and hypertension. She also notes a 12 pack year history of smoking without history of pancreatitis .CT abdomen demonstrated a 2 cm hypodense mass in the tail of her pancreas. An evaluation using Endoscopic Ultrasound and biopsies revealed a 2.5 cm hypoechoic mass in the tail of the pancreas with peripancreatic lymphadenopathy. Review of pathology suggested a high grade carcinoma with squamous differentiation. CA 19-9 was normal. Initial CT scan showed no hepatic metastasis. Squamous metastasis from other primary focus was ruled out with a head and neck CT. Repeat CT abdomen and chest at 8 weeks, prior to therapy revealed rapidly progressive disease with gastric and hepatic metastasis. Patient is now receiving palliative chemotherapy for pancreatic cancer (Gemcitabine and Abraxane) along with radiation therapy. Primary SCC of the pancreas is an extremely rare neoplasm of pancreas with rapid progression and worse outcomes than adenocarcinoma. 95% of patient have locally advanced or stage 4 disease at diagnosis. Squamous metastasis from a primary focus elsewhere should be excluded prior to surgery and chemotherapy. Putative causality has been attributed to stem cell differentiation and ductal metaplasia. Prognosis is poor, the median survival is 7 months while those with palliative treatment have only a median 3 month survival.

Liquid nitrogen spray cryotherapy (LNSCT) is safe, well-tolerated, and effective therapy for dysplastic Barrett's esophagus (BE). The efficacy of LNSCT for esophageal intramucosal adenocarcinoma (IMC) is less well known. To assess the efficacy and rate of neoplastic progression in patients (pts) with esophageal IMC treated with LNSCT in a multicenter U.S. registry. This is a multicenter prospective registry of subjects treated with truFreeze LNSCT at 4 community and 11 academic sites in the United States with a diagnosis of esophageal IMC. Outcome measures included complete eradication of carcinoma (CE-neo), dysplasia (CE-D), and intestinal metaplasia (CE-IM), rate of neoplastic progression, and adverse events. Among 39 subjects, mean age (SD) was 69.7 ± 9.8 years and 32 (82.1%) were male. Mean BE segment length (SD) was 5.2 ± 6.2 cm. 82.1% (32/39) of pts underwent EMR prior to LNSCT, and 28 (71.8%) had persistent IMC at time of treatment. Five pts (12.8%) previously received radiofrequency ablation. With median follow up of 20 months (range 0-47, IQR 12-27), CE-neo was 69.2%, CE-D was 56.4%, and CE-IM was 41.0% after median 2 LNSCT treatments (range 1-8, IQR 1-3). Median dosimetry (seconds/spray site x sprays/site) was 20 seconds x 2 (range 1-4). Median follow up from last LNSCT treatment was 16 months (range 0-47, IQR 8-25). Four (10.3%) had persistent IMC, 1 (2.6%) progressed to invasive adenocarcinoma (EAC). No adverse events were reported, including bleeding, stricture, or perforation. Status at last follow up: 4 - deceased (none due to EAC), 1 - withdrawn (underwent esophagectomy), 2 - lost to follow-up, 31- alive and actively enrolled in study. Kaplan-Meier survival curve is shown below. In a national registry of patients receiving LNSCT for treatment of esophageal IMC, 69% of patients achieved eradication of cancer at median follow up of 16 months after treatment. Over 50% achieved eradiation of dysplasia, 10% had persistent IMC despite treatment. In pts with esophageal IMC, LNSCT is effective in eliminating cancer and dysplasia. Progression to invasive adenocarcinoma was rare.