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sstage IV. RESULTS: All pancreatic tumors were visualized by HIFU ultrasound monitorsystem. Treatment data in Stage III and IV were followed; mean tumor size was 31.8 vs30.1 mm, mean treatment sessions: 2.6 vs 2.7 times, mean total treatment time: 2.7 vs 2.2hours, mean total number of irradiation: 2801 vs 1769, respectively. There was no significantdifference in treatment data between two groups. The effects of HIFU therapy in Stage IIIand IV were the following; the rate of complete tumor ablation was 87.5 vs 71.4%, the rateof symptom relief effect was 80 vs 56%, the effectiveness of primary lesion was CR:0, PR:2,SD:13, PD:1 vs CR:0, PR:2, SD:10, PD:2, and primary disease control rate (DCR) more thanSD was 93.8% vs 78.6%. Mean survival time (MST) after HIFU therapy was 14.1 vs 7.2month, respectively (p,0.01, p=0.0009). MST after diagnosis as PC was 32.4 vs 14.8 month,respectively (p,0.01, p=0.002). Combination therapy of HIFU with chemotherapy in StageIII was better result than common GEM single agent chemotherapy in our hospital. (MST:14.9month). CONCLUSION: This study suggested that HIFU therapy has the potential ofnew method of combination therapy for non-metastatic PC.

Sa1147

Efficacy of Second-Look Endoscopy After Endoscopic Hemostasis in AcutePeptic Ulcer Bleeding : Risk Factor Analysis of Recurrent BleedingCheol Woong Choi, Hyung Wook Kim, Dae Hwan Kang, Su Jin Kim, Young Mi Hong,Byoung Hoon Ji, Joung Boom Hong, Min Dae Kim, Jae hyung Lee

Background and aims : Endoscopic therapy for gastrointestinal bleeding (GIB) is highlyeffective. But rebleeding occurs in 10% to 25% of cases after endoscopic hemostasis. Clinicalvalue of a second-look endoscopy after initial endoscopic hemostasis with high-dose protonpump inhibitor (PPI) infusion therapy is controversial. We aim to determine whether routinesecond-look endoscopy is necessary and to assess predictors of rebleeding after endoscopichemostasis and high dose PPI medication. In addition we make a comparison betweenRockall score and AIMS65 score. Patients and Methods : Both endoscopic and clinical datawere analyzed in 101 acute peptic ulcer bleeding patients during August 2008 to June 2012.All peptic ulcer bleeding patients were treated with high-dose PPI infusion therapy afterendoscopic hemostasis. To know the patients who need second-look endoscopy, we analysedpredictors of rebleeding in patients with high risk on second-look endoscopy. Results : Therebleeding rate after endoscopic hemostasis and high dose PPI infusion was 11.8% (12/101). The pre-endoscopic predictors of rebleeding were use of NSAIDs (p,0.01), transfusionrequirements before endoscopic hemostasis (p=0.013), albumin level (p=0.042), completeRockall score (p=0.043), Forrest type(I, IIa) (p=0.017). No significant difference was foundfor the factors of sex, age, initial hemoglobin, systolic blood pressure, diastolic blood pressure,heart rate, INR level, use of antiplatelet drug, anticoagulant drug, diabetes, liver cirrhosis,cardiovascular disease, chronic kidney disease, malignancy, ulcer location, ulcer size ≥ 1cm,AIMS65 score. In univariated analysis of high risk group (Forrest type I or IIa), liver cirrhosis(p=0.040) and complete Rockall score ≥ 4 points were the risk factors of rebleeding. TheMultivariated analysis of high risk group identified complete Rockall score ≥ 4 as onlystatistically significant risk factor (odds ratio, 5.123; 95% CI, 1.587-16.542, p=0.006).Conclusion : It is inappropriate to perform routinely second-look endoscopy after endoscopichemostasis and PPI treatment because of low rebleeding rate. Even though all patients arenot necessary for second-look endoscopy, patients with complete Rockall score above 4points should consider second-look endoscopy.Univariate analysis of factors associated with high risk group

Multivariated analysis of factors associated with rebleeding

S-214AGA Abstracts

Sa1148

Low Adverse Event Rate Using the Vessel Sealing System Technique in MajorHepatic Resection Alone and in Simultaneous Colon and Liver ResectionsLori Uyeno, Louisa Chiu, Julian Sanchez, Gagandeep Singh

Background: Multiple surgical techniques and devices have been developed to minimizeblood loss and improve outcomes in hepatic resection. Several studies have reviewed multipletechniques for liver parenchymal transection. More recent literature evaluating the vesselsealing system suggests that the use of this device is a safe technique; though significantdecrease in operating room (OR) time or blood loss compared to other techniques is notclear. Furthermore, outcomes of hepatic transection technique in simultaneous combinedcolon and liver have not been fully examined. Methods: Our study is a single-institutionretrospective case series review of experience with vessel sealing system for major hepaticresection and simultaneous colon and liver resection. Major hepatic resection was definedas .30% parenchymal resection or complex central resection. The primary outcomesreviewed were postop liver function, length of hospital stay (LOS), mortality, and adverseevents (AEs). Secondary endpoints were intraoperative blood loss (EBL) and operative time.Results: A total of 51 consecutive patients underwent major liver resection for malignantdisease. 37% (19/51) were simultaneous colon and liver resection with primary anastomosis.All patients underwent open laparotomy. The majority of patients underwent resection formetastatic disease to the liver: 32 colorectal cancer (CRC), 6 neuroendocrine (NE), 5 other.Resection for other cancers include: 4 gallbladder cancer and 4 hepatocellular carcinoma(HCC). The median age was 66 years (23-90 years) with equal number of women to men.All 51 patients had normalization of liver function post-operatively. One patient (2%) hadreturn to OR for a colon anastomotic leak in a simultaneous colon and liver resection. Therewere no documented bile leaks or intra-abdominal infections. The median LOS was 7 days(4-24days) for all cases and 9 days (5-24days) for simultaneous. No inpatient or 30-daydeaths occurred. The median EBL was 250 mL (50-3000mL) for all cases but significantlyhigher in simultaneous cases 850mL (15-3000mL). The median OR time for all casescompared to simultaneous was 7 hours (2.5-12hours) versus 8 hours (5-10hours). Conclu-sions: Mortality and surgical technique related AEs were low in our series of major hepaticresection using the vessel sealing system in both hepatic only and simultaneous colon cases.EBL was low with rates were similar to other reports. LOS was shorter than reported inother studies. In our institutional experience, the vessel sealing device appears to be a safeand effective technique for major hepatic resection including simultaneous colon cases withminimal post-operative adverse events including no bile leaks or intra-abdominal infectionsand blood loss.

Sa1149

Superior Diagnosis of H. pylori Infection With 14C-Urea HelicapTM CapsulesVersus Standard Pytest® CapsulesThomas J. Borody, Antony R. Wettstein, Simon Benstock, Anna Nowak, Sarah J.Finlayson, Jordana Campbell

Introduction:Helicobacter pylori (Hp) exists in around 30% of the US population and is oftenasymptomatic1. Hp is a known carcinogen with direct links to gastric neoplasms, makingaccurate diagnosis essential2. Currently, histology is considered the gold-standard diagnostic,however it is invasive, costly and time-consuming. The urea breath test (UBT), which useseither 13C- or 14C-labelled urea, is a non-invasive, convenient and inexpensive alternative.PYTest® is the most widely used 14C-UBT, however it has proven inferior to the Heliprobe®UBT3,4. For the first time we compared the HeliCapTM and PYCapTM to evaluate whichprovides the most accurate diagnosis. Method:An Ethics-approved, open-label, comparativetrial was conducted in 80 patients 18-75yrs undergoing routine upper endoscopy, with 60patients (24M, 57±10yrs; 36F, 54±12yrs) completing the study requirements to date. Biopsieswere collected for histology and rapid urease testing (RUT). Post-procedure, patients under-went either the HeliCapTM-UBT (H-UBT) or PYCapTM-UBT (P-UBT) and were re-tested 10-13 days later with the other in a cross-over fashion. Breath samples were processed by anindependent, blinded technician. Equivocal results were not re-tested, and were includedin the analysis as false results. Results:Histology and RUT results were Hp-negative for 57/60 (95%) patients. For H-UBT, 3 patients (5%) tested positive, 54 patients (90%) negativeand 3 results proved equivocal. The P-UBT identified 3 patients as Hp-positive and 48 (80%)as negative with 9 (15%) equivocal results. H-UBT demonstrated a specificity and sensitivityof 94.7% and 100% respectively. In contrast, P-UBT achieved only 84.2% and 66.7%respectively. H-UBT displayed a slightly higher NPV than P-UBT (100% vs 96%), but aconsiderably higher PPV (50% vs 20%). H-UBT diagnosed infection with an accuracy of95%, considerably greater than the 83.3% seen with P-UBT. Discussion:HeliCapTM provedsuperior to PYCapTM in all the parameters analysed, with sensitivity particularly improved(100% vs 66.7%). PPV was dramatically lower for both UBTs when compared to publisheddata, likely due to the small number of Hp-positive patients and the inclusion of equivocalresults as false. The majority of UBT studies either retest or redefine the results range toeliminate an equivocal result, thereby failing to reflect the real-world applicability of suchtests. The preliminary results of this study indicate the superiority of HeliCapTM comparedto PYCapTM in the diagnosis of Hp. The inclusion of equivocal results in the analysis adds

credibility to the study, as it more accurately reflects the experience in clinical practice. 1.Grad YH et al. Am J Epidemiol 2012; 175:54-9 2.Watanabe T et al. Gastroenterol 1998;115:642-8 3. Hegedus O et al. Eur J Gastroenterol Hepatol 2002;14:513-20 4. Borody TJ et al.Gastroenterol 2008;134:A-329

Sa1150

Efficacy of Pharmacological Therapies for the Treatment of Opioid-InducedConstipation: Systematic Review and Meta-AnalysisDarren M. Brenner, Alexander C. Ford, Philip S. Schoenfeld

ABSTRACT Objectives: There has been no definitive synthesis of the evidence for any benefitof pharmacoligical therapies in the treatment of opioid-induced constipation (OIC). Weconducted a systematic review and meta-analysis to address this deficit. Methods: Wesearched MEDLINE, EMBASE, EMBASE Classic, PubMed, and the Cochrane central registerof controlled trials through to October 2012 to identify placebo-controlled trials of μ-opioidreceptor antagonists and other standard laxatives in the treatment of adults with OIC. Nominimum duration of therapy was required. Trials had to report a dichotomous assessmentof overall response to therapy, and data were pooled using a random effects model. Effectof μ-opioid receptor antagonists was reported as relative risk (RR) of failure to respond totherapy, with 95% confidence intervals (CI). Results: Seventeen RCTs met our inclusioncriteria. Fourteen trials, containing 4101 patients, utilzed μ-opioid receptor antagonists, 2trials (data limited to abstracts) containing 892 patients utilized lubiprostone, and 1 trialenrolling 196 patients utilized prucalopride. Mu-opioid receptor antagonists were superiorto placebo for the treatment of OIC (RR of failure to respond to therapy = 0.69; 95% CI0.63-0.75). Methylnaltrexone (six RCTs, 1610 patients, RR = 0.66; 95% CI 0.53-0.83),naloxone (four trials, 798 patients, RR = 0.64; 95% CI 0.56-0.72), and alvimopan (fourRCTs, 1693 patients, RR = 0.71; 95% CI 0.65-0.78) were all superior to placebo (Figure1). Total numbers of adverse events, diarrhea, and abdominal pain were significantly morecommon when data from all RCTs were pooled. Reversal of analgesia did not occur morefrequently with active therapy. The limited data for lubipsotone and prucalopride did notallow for futher assessment. Conclusions: μ-opioid receptor antagonists are safe and effectivefor the treatment of OIC.

Sa1151

Effect of Linaclotide in the Treatment of Irritable Bowel Syndrome andChronic Constipation: A Meta-AnalysisDina Ahmad, Mohammad Esmadi, Belal Firwana, Abhishek Choudhary, Michelle L.Matteson, Matthew L. Bechtold

Background: Irritable bowel syndrome with constipation (IBS-C) and functional constipationare common gastrointestinal disorders with limited treatment options. Recently, the medica-tion linaclotide was FDA-approved for the treatment of these difficult conditions. The aimof our study was to perform a meta-analysis of existing clinical trials to estimate the efficacyand safety of different daily doses of oral linaclotide in the management of IBS-C and chronicconstipation. Methods: A systematic search of PubMed, CINAHL, Scopus, Cochrane databaseof systematic reviews, and clinical trials.gov registry was performed in November 2012. Twoindependent reviewers systematically identified prospective randomized controlled trials(RCTs) published in English language that compared the effect of oral linaclotide versusplacebo in adults with IBS-C and chronic constipation. A meta-analysis was performed usinga random effects model to assess the primary outcome (three or more complete spontaneousbowel movement (CSBM) per week and an increase of at least one CSBM per week frombaseline) and secondary outcome (frequency of adverse events). Subgroup analysis wasperformed by dividing the studies into a high-dose group (290-300 mcg daily) and low-dose group (145-150 mcg daily). Review Manager 5.1 software program was utilized forstatistical analysis. Results: The search yielded six studies involving 3,644 patients. Themean percentage of patients who reached the primary endpoint was 9% in the placebogroup (n=1,375) and 22% in the linaclotide group (n=2,227). For the primary outcome ofCSBM, linaclotide demonstrated a statistically significant improvement as compared to pla-cebo (OR 3.42; 95% CI: 2.06-5.68; p,0.01). However, in regards to the secondary outcome,linaclotide showed a statistically significant increase in adverse events as compared to placebo(OR 1.28; 95% CI: 1.11-1.48; p,0.01). In subgroup analysis, linaclotide of 145-150 mcgand 290-300 mcg daily demonstrated statistically significant improvements in CSBM (OR3.50; 95% CI: 1.92-6.38; p,0.01 and OR 3.84; 95% CI: 2.20-6.69; p,0.01, respectively)as compared to placebo. However, linaclotide of 145-150 mcg and 290-300 mcg dailyrevealed a statistically significant increase in adverse events (OR 1.39; 95% CI: 1.09-1.76;p,0.01 and OR 1.24; 95% CI: 1.07-1.45; p,0.01, respectively) as compared to placebo.Conclusions: Linaclotide appears to be effective in the treatment of IBS-C and chronicconstipation but does have more adverse events, which do not appear to be dose-related.

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Given the limited options in the treatment of IBS-C and chronic constipation, linaclotideseems to be a viable option.

Sa1152

Can We Personalize Colorectal Cancer Screening? A Systematic Review ofModels to Predict Risk of Colorectal NeoplasiaGene K. Ma, Uri Ladabaum

Background: Screening can significantly decrease colorectal cancer (CRC) incidence andmortality. An undifferentiated screening approach to all "average risk persons" starting atage 50 may be inefficient and costly compared to a more personalized approach based onrisk. Multiple clinical risk factors for CRC have been identified, and several predictionmodels for risk of colorectal neoplasia have been developed in recent years. CRC screeningpractice has not yet been influenced by risk prediction models. Aims: To perform a systematicreview of risk prediction models for colorectal neoplasia risk. Methods: Two investigatorsindependently searched MEDLINE, SCOPUS, and the references of identified studies throughNovember 15, 2012, yielding 1,366 MEDLINE and 2,665 SCOPUS titles, and 2 additionaltitles from references. Titles and, when indicated, abstracts were reviewed against a prioriinclusion criteria to select studies that developed or validated a model to predict risk ofcolorectal neoplasia based on clinical risk factors. The investigators independently appraisedthe quality of each study and abstracted pre-specified elements into standardized dataextraction tables. Results: Seventeen studies were identified for full text review, and 14studies conducted between 1990 and 2012 met inclusion criteria (Table). Twelve studiesdeveloped a new risk assessment model for either advanced neoplasia (AN) or CRC, andtwo studies (Freedman et al.; Levitzky et al.) were validations of previously developed models.Most models addressed the entire colorectum; one focused on proximal AN (Imperiale etal.). The models varied with respect to derivation methods, target population (gender,country, ethnicity, specific subgroup), and number and type of risk factors included (Table).The risk factor most frequently represented was age (7/12 models). Six models defined 3tiers of risk, 2 models defined 2 tiers, and the rest did not define tiers. For most modelsthat defined tiers, the difference in risk for the highest vs. lowest risk tier ranged from 2-to 4-fold (Table). The area under the receiver operating characteristic curve (AUC) or c-statistic for most models did not reach the 0.70-0.80 range that is typically considered toreflect good discriminatory power (Table). Conclusions: The multiple risk prediction modelsfor colorectal neoplasia display variability in target population and risk factors included,and most require external validation and testing in more diverse populations. Most modelshave relatively weak discriminatory power. Significance: A valid, simple colorectal neoplasiarisk score with sufficient discriminatory power could allow the personalized tailoring ofCRC screening based on risk. It remains to be determined whether the discriminatory powerof existing models is acceptable for clinical use.Models to predict risk of colorectal neoplasia

AN = advanced neoplasia, CRC = colorectal cancer, AUC = area under the receiver operatingcharacteristic curve, CI = confidence interval, FDR = first degree relative, FH = family history,RR = relative risk, SDR = second degree relative

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