14 sites (5 in the fundus, 3 in the corpus, 2 in the antrum and 4 around the pyloris). TheCLE images were compared to the pathologic results. Results : 27 patients with chronicatrophic gastritis (17 men, 10 women, mean age ± SD, 65 ± 13 years) were included. CEhas detected elevated lesions in 5 patients (18.5%), plane lesions with modified architectureof the mucosa in 10 patients (37%) and was normal in 12 patients (44.5%). Among the 5elevated lesions, CLE has shown LGD in 3/5 (60%) and 2 cancers. The pathologist confirmedthe 2 adenocarcinomas and reclassified 1 LGD in HGD. Among the plane lesions, CLE hasshown neoplasia in 4 patients (4/10, 40%) and the pathologist in 6 cases (6/10, 60%). Innormal CE patients, CLE has detected neoplasia in 4/12 (33%) confirmed by the pathologist.Compared to pathologist results, with this small number of patients, CLE had a sensitivityand specificity of 85% and 71% to detect neoplasia, respectively. Conclusion : Neoplasiafound by pathologist in 48% (13/27) was detected by CLE in 40%(11/27). CLE detectedLGD in 4 cases when the CE was normal (n = 12) and in 4 cases when CE showed amodified architectural aspect of the pits (n = 10). These preliminary results show thepromising interest of CLE in the detection of neoplasia, which has to be confirmed in alarger group of patients.

Tu1135

Early Detection of Acute Graft-Versus-Host Disease by Wireless CapsuleEndoscopy Combined With Probe-Based Confocal Laser Endomicroscopy:Timeto Change the Diagnostic Algorithm?Emmanuel Coron, Mohamad Mohty, Valérie Laurent, Marc Le Rhun, Tamara Matysiak-Budnik, Jean Paul Galmiche

Introduction: Acute graft-versus-host disease (GVHD) is a potentially lethal complication ofallogeneic hematopoietic stem cell transplantation (AHSCT). Endoscopic examinations thatrequire sedation are invasive in these fragile patients, and standard biopsies carry a highrisk of bleeding complications. Our aim was to determine whether probe-based confocallaser endomicroscopy (pCLE) combined with wireless capsule endoscopy (WCE) coulddetect early lesions of GVHD. Patients and methods: Fifteen consecutive patients undergoingAHSCT were prospectively scheduled for a clinical examination, biological tests, and smallbowel WCE (Given imaging, Israel) and pCLE (Mauna Kea Technologies, France) of theduodenum and rectosigmoid. Standard biopsies were taken at the same sites for conventionalhistology. All these examinations were scheduled between day 21 and day 28 followingAHSCT, whether symptoms were present or not.WCE and pCLEwere analyzed blindly to thefinal diagnosis, which was based upon the modified Glücksberg scoring system (considered asgold standard). The results were expressed semi-quantitatively for the severity of GVHD,from 0 to 4 (Glücksberg, WCE) or from 0 to 3 (histology, pCLE). Correlation was assessedby the Spearman rank test. Results were expressed in terms of sensitivity and specificity,whether GVHD was present or absent, independently of the severity. Results: Eight patientsdeveloped acute GVHD, classified as grade I (n=3), II (n=4) and IV (n=1). Only one patienthad symptoms suggestive of acute GVHD prior to the examinations. The Spearman ranktest showed a positive correlation between, on the one hand, the Glücksberg score, and onthe other hand, WCE (rho coefficient=0.543; p=0.036) and pCLE (rho coefficient=0.727;p=0.002). In contrast, no correlation was noted between the Glüsckberg score and standardhistology (rho coefficient=0.481; p=0.069). Sensitivity of WCE, pCLE and histology were50%, 87.5% and 50%, respectively. Specificity of WCE, pCLE and histology was 80%,71.5% and 80%, respectively. No complication related to endoscopic examinations wasreported. Conclusions: Our results demonstrate that pCLE is the most sensitive method forearly detection of GVHD and correlates well with the severity of the disease, even in theabsence of symptoms. WCE has a good specificity but a suboptimal sensitivity. Therefore,the algorithm for the detection of GVHD might include WCE as a first line examination(sufficient if positive) and, in case of negative WCE, further examination using pCLE, whichis more sensitive and less invasive than standard biopsies.

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The Effects of Age and Cholecystectomy on Common Bile Duct Diameter. AMyth Comes True - As Measured by Endoscopic Ultrasonography (EUS)Fabiana Benjaminov, Jorge Leichtman, Fred M. Konikoff

Backround: Dilatation of the common bile duct (CBD) is an important indicator of bile ductobstruction. An increased CBD diameter has also been attributed to aging and previouscholecystectomy. These relationships are, however, controversial and based mainly on oldstudies and methodologies. In the last decade, EUS has established itself as a highly sensitiveand accurate tool for assessing the common bile duct. The aim of this study was to evaluatethe relationship between age and cholecystectomy and CBD diameter, as measured by EUS.Patients and methods: All patients, who underwent EUS in our institution between January2001 and December 2009, were included. Patients with a finding that can cause bile ductobstruction were excluded. The diameter of the CBD was measured as a routine part of theexamination, in the distal portion, above the papilla. The patients were divided into 5 agegroups (Group 1: <49y, group 2: 50-59y, group 3: 60-69y, group 4: 70-79y and group 5:>80y). The mean CBD diameter of each group was calculated and compared with the others,the influence of cholecystectomy, gender and liver function tests (LFT's) were also assessed.Results: Six hundred forty seven patients were included in the study (66% women). Onehundred fifty three (23.6%) were post cholecystectomy. Groups 1-5 consisted of164,113,118,169 and 83 patients, respectively. The mean CBD diameter in the 5 groupsin patients with an intact gallbladder was 4.4±1.2 mm, 4.9±1.4 mm, 5.4±1.6 mm, 5.7±1.7mm and 6±1.6 mm, respectively. There was no difference between the first three groups,but the CBD diameter was significantly wider in groups 4 and 5 (5.7±1.7 mm and 6±1.7mm, respectively; p<0.001). In all age groups the post-cholecystectomy patients had asignificantly wider CBD than those with an intact gallbladder (group 1- 5mm1 Vs 4.4mm,group 2- 5.8mm Vs 4.9mm, group 3- 6.6mm Vs 5.4mm, group 4- 6.6mm Vs 5.7mm, group5- 9.6mm Vs 6mm) ( p= 0.006,0.008, 0.001, 0.006, <0.001 respectively). The CBD diameterincreased linearly in correlation with time from cholecystectomy (p=0.009). There was nodifference in the CBD diameter between men and women with an intact gallbladder, butafter cholecystectomy, women had a wider CBD (p=0.013). Patients with elevated LFT'shad wider CBD regardless of the gallbladder status (p=0.000). Conclusions: This EUS study

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confirms that the CBD diameter increases with age, although later in life (> age 70) thanpreviously thought. Cholecystectomy also causes CBD dilatation, in women more than inmen, increasing linearly with the passage of time.

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Interobserver Agreement Among Radiologists for Pancreatic Cysts Using MRIKoen de Jong, Chung Y. Nio, Banafsche Mearadji, Saffire S. Phoa, Marc R. Engelbrecht,Marcel G. Dijkgraaf, Marco J. Bruno, Paul Fockens

Background & Aims Magnetic Resonance Imaging (MRI) is considered the best radiologicimaging modality for the morphologic characterization of pancreatic cysts (PC) but little isknown about the interobserver agreement. Aim of this study was to assess the degree ofinterobserver agreement of MRI in the diagnostic work up of PC among four experiencedradiologists. Methods MRI images of 64 patients with PC (32 without, 32 with histologicalconfirmation) were reviewed. In the latter group histological diagnoses were as follows:pseudocyst (4), serous cyst adenoma (2), IPMN (17), mucinous cystic neoplasm (8), cysticneuroendocrine tumor (1). Before reviewing, all radiologists were exposed to a training setdemonstrating specific MRI-features of PC. Observers were blinded to clinical and histologicalresults. Features scored included: septations, nodules, solid components, pancreatic ductcommunication and wall thickening (>2mm). Radiologists were asked whether they consid-ered the PC mucinous and if the PC had malignant features. Furthermore, a presumptivediagnosis had to be specified. Intraclass correlation coefficient (icc) was used to measureagreement within the group. Icc values greater than 0.80 were considered in excellentagreement, 0.61-0.80 were considered good, 0.41-0.60 moderate, 0.21-0.40 fair and <0.20poor. Results Interobserver agreement for septations and nodules was fair (icc=0.29 and0.27). Agreement for the presence of solid components was poor (icc=0.07), agreement forcommunication with the pancreatic duct was moderate (icc=0.48) and agreement for wallthickening was also moderate (icc=0.44). There was only fair agreement between radiologistsfor the discrimination between mucinous and non-mucinous PC (icc=0.31). Agreement fora specific diagnosis was borderline fair (icc=0.22) in the whole set of MRI`s (n=64) andpoor (icc=0.05) in the group with histological confirmed PC (n=32). Interobserver agreementfor the presence of malignant features was fair (icc=0.32). Accuracy rates for a specificdiagnosis in the group with histological confirmed PC were as follows for each individualradiologist: 56%(1), 53%(2), 63%(3) and 76%(4). Conclusions Interobserver agreement waspoor to moderate for individual PC features and there was poor agreement for a specificdiagnosis in histologically confirmed PC. Accuracy rates for a specific diagnosis were limitedbut comparable between radiologists. In this study, MRI morphology alone did not allowfor a reliable discrimination between different types of PC.

Tu1138

An Optical Cancer Diagnosis With Fluorescence PolarizationTsuyoshi Kaneko, Hirofumi Matsui, Osamu Shimokawa, Yumiko Nagano, Rai Kanho,Hideo Suzuki, Kuniaki Fukuda, Toshikazu Moriwaki, Masato Abei, Shinji Endo, HirokoIndo, Hideyuki J. Majima, Yuji Mizokami, Ichinosuke Hyodo

BACKGROUND AND AIMS: Membrane fluidity of cellular membrane reflects the cellularmembrane stability, and changes in response to several pathophysiological processes. Mem-brane fluidity changes can be detected by the change of the fluorescence polarization (FP)using fluorescent indicators such as decanoylaminofluorescein (DAF). We have alreadyshown at the previous DDW meeting that the FP value of gastric cancer was significantlysmaller than that of normal tissue in human gastric cancer specimens. However, the pathophy-siological mechanism remained unknown. Previous studies showed that cellular membranesof cancer tissues were peroxidized by reactive oxygen species (ROS) and that lipid peroxida-tion increased membrane fluidity. We thus hypothesized that increased ROS generated incancer tissue induces cellular lipid peroxidation of cancer membrane, which increasedmembrane fluidity. In addition, we evaluated the diagnostic accuracy of FP in human gastriccancer specimens using pathological examinations as a gold standard. METHODS: A: Weused gastric epithelial RGM1 cells and its cancerous transformed mutant RGK as normaland cancer model, respectively. We also established RGK' cells that overexpressed manganesesuperoxide dismutase protein, which scavenges mitochondrial ROS.We examined intracellu-lar concentrations of ROS, membrane lipid peroxidation and FP value with fluorescentprobes hydroxyphenyl fluorescein (HPF), diphenyl-1-pyrenylphosphine (DPPP) and DAF,respectively. B: Gastric cancer specimens from eleven patients were investigated. FP valuesof each sample were measured with a specially designed system composed with an intensifiedCCD, a fluorescence microscope and an image-processor. We compared each FP value ofthe specimens with the result of pathological examinations to evaluate the diagnostic accuracyof FP value analysis. RESULTS: A: Intracellular ROS concentration, amount of lipid peroxida-tion and membrane fluidity were significantly increased in cancerous RGK cells than thoseof normal RGM1 cells, but were significantly decreased in mitochondrial ROS-scavengedRGK' cells than those of RGK cells. B: The sensitivity and specificity of FP analysis on humangastric cancer specimens was 84.3% and 70.4%, respectively. CONCLUSION: In cancercells, higher ROS concentration is most likely to induce a smaller FP value. The FP analysiswas demonstrated to be a clue to accurately diagnosing cancerous areas. Since this is anoptical method, it is providing little invasion and is mountable on an endoscopic system.

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Detection and Quantification of Intestinal Inflammation In Vivo and Ex Vivoby Activatable Molecular ProbesShengli Ding, Randall E. Blue, Jessica Bradford, Pauline K. Lund, Douglas R. Morgan

Background: Activatable near-infrared fluorescent (NIRF) probes have demonstrated promisefor ex vivo detection of intestinal tumors [1, 2]. The ability of specific molecular probes todetect gastrointestinal inflammation has not been well studied. Colonic inflammation isassociated with up-regulation of cathepsins and matrix metalloproteinases (MMPs). Weevaluated 7 different NIRF probes (cathepsin or MMP based ProSense/MMPSense probes)

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