cancer diagnosis, identified through linked Medicare claims data. We considered intervalcancers as those diagnosed in patients with colonoscopy between 6-36 months previously,and all others to have detected cancers. The presence of diverticulosis was identified throughdiagnosis codes during the previous three years. We compared the prevalence of diverticulosisin interval and detected cancers according to tumor location. The independent associationof diverticulosis was then evaluated in a logistic model with generalized estimating equationsaccounting for clustering by endoscopists and stratified by tumor location. The modeladjusted for demographics, comorbidity and endoscopist characteristics. Results: We identi-fied 57,839 patients, including 53,647 with detected cancers and 4,192 (7.2%) with intervalcancers. A previous diagnosis of diverticulosis was documented in 69.3% of interval cancersand 26.9% of detected cancers (p,0.001). In all segments of the colon, the prevalence ofa diverticulosis diagnosis was higher in interval cancers than in detected cancers (Table)(p,0.001 for all comparisons). In the multivariable analysis, diverticulosis was stronglyassociated with interval cancer risk in both the proximal colon (cecum to splenic flexure)(Adjusted Odds Ratio (AOR) 5.43, 95% CI 4.98-5.93) and distal colon (descending, sigmoid)(AOR 6.59, CI 5.65-7.69). Conclusions: A previous diagnosis of diverticulosis is a strongrisk factor for interval colon cancer regardless of tumor location. Given the greater prevalenceand extent of diverticulosis in the left colon, it suggests that factors other than impairedvisualization of neoplasia between diverticuli are involved in the pathogenesis of intervalcancer.Prevalence of Diverticulosis

Mo1200

Demographic and Behavioural Predictors of Ongoing Adherence to FaecalOccult Blood Test Screening for Colorectal CancerAmy Duncan, Deborah A. Turnbull, Carlene J. Wilson, Stephen R. Cole, Joanne M.Osborne, Graeme P. Young

Background: Few studies have identified predictors of adherence to ongoing screening (re-screening). Our aim was to identify demographic and behavioural variables associated withadherence behaviour in a longitudinal screening program for colorectal cancer. Methods: Arandom sample of 4000 South Australian men and women aged 50-74 were invited toparticipate in a health behaviour survey. Respondents (n=1941, response rate 48%) wereeligible for a program of free faecal occult blood test-based screening. Following annualscreening offers, patterns of participation across the three rounds were recorded as one offive behaviours; consistent re-participation (adherent with all screening rounds), consistentrefusal (adherent with no screening rounds), drop out (adherent with earlier but not laterrounds), intermittent re-participation (adherent with alternate rounds) and delayed entry(adherent with later but not initial round(s)). Participants who did not participate becauseof recent colonoscopy were excluded from analyses (n=240, 12.4%) as were respondents withincomplete survey data (n=148, 7.6%) resulting in a final sample size of 1540. Multivariategeneralised linear models were used to determine variables associated with adherence categor-ies relative to consistent re-participation. Results: Consistent re-participation across threerounds was 55.8%. Less satisfaction with prior FOBT was predictive of drop out (RR= 0.58,p,.001, 95% CI 0.48-0.71), delayed entry (RR=0.77, p=.007, 95% CI 0.63-0.93) andconsistent refusal behaviours (RR=0.74, p=.003, 95% CI 0.61-0.90) amongst those who hadpreviously participated in FOBT screening. Less self-efficacy (RR= 0.97, p ,.05, 95% CI=0.95-0.99) and less response efficacy (RR=0.93, p ,.05, 95% CI= 0.95-0.99) predictedconsistent refusal and less self-efficacy (RR=0.97, p,.05, 95% CI 0.95-0.99) and greaterbarriers (RR=1.05, p,.05, 95% CI 1.01-1.10) predicted drop out however the differencewas not substantial. Several demographic variables were associated with adherence, forexample, lack of health insurance predicted drop out behaviour (RR=1.44, p=.020, 95% CI1.06-1.96), male gender predicted delayed entry (RR= 1.71, p= ,.001, 95% CI 1.28-2.29)and fewer general practitioner visits predicted intermittent re-participation (RR=0.80, p=.015, 95% CI 0.67-0.96). Conclusions: Different adherence sub-groups were associated withspecific combinations of demographic and behavioural characteristics. Satisfaction with priorscreeningwas an important predictor of ongoing adherence. Interventions to improve ongoingadherence should consider the unique characteristics of non adherent subgroups. An explora-tion of factors that contribute to screening satisfaction is recommended.

Mo1201

A New Screening Method for Colon Cancer by Measuring Iron Concentrationin the Gut Lavage FluidTsuyoshi Kaneko, Hirofumi Matsui, Hideo Suzuki, Toshiaki Narasaka, Junji Fukuda,Shohei Kimura, Hiroaki Suzuki, Yuji Mizokami, Ichinosuke Hyodo

Background & Aims: A fecal occult blood test (FOBT) which checks up hidden blood inthe stool was performed for screening of colon cancer. In Japan, over six million peopleused to receive FOBT every year and more than 180,000 patients were sorted for totalcolonoscopy because of suspicion for neoplasm. In fact, FOBT is helpful to detect advancecolon cancer and reduce cancer death in Japan. However, FOBT has reported to have highfalse-positive rate for hemorrhoid patients and high false-negative rate for early colon cancer.To improve those problems, we developed a new test looking for iron (Fe) concentration

S-605 AGA Abstracts

not in the stool but in the gut lavage fluid which used to be easily obtained during colonoscopypreparation procedures. Since neoplasm tissue has been reported to show a larger amountof Fe, the gut washing fluid may have high Fe concentration. To elucidate this possibility,we investigated relations between endoscopic findings and Fe concentration in the gut lavagefluid. Methods: Gut lavage fluids from 40 patients who were received colonoscopy at TsukubaUniversity Hospital were investigated. The fluids were collected at rectum through vacuumvent of endoscope. Fe concentration of each sample was measured with a specially designedion-selective membrane electrode system that has excellent selectivity for Fe ion. We com-pared each Fe concentration of the sample with the finding of endoscopic examinations.Result: 10 cases that have no malignancy and no polyp showed up to 2 μM of Fe in thegut lavage fluid. On the other hand, 10 cases that have colon cancer showed over 200μMof Fe in that fluid. The remaining 20 cases that have adenomatous polyp showed positivelycorrelated with Fe concentration and size of polyp. Conclusion: The analysis of Fe concentra-tion in the gut lavage fluid was demonstrated to be a clue to accurate screening for coloncancer. Since Fe measurement using ion-selective membrane electrode provides both a real-time measurement and a compact size mountable on a capsule endoscope, it could be acandidate for a new diagnostic tool.

Mo1202

Pancreatic Cancer Screening in a Cohort of High Risk Individuals Presentingfor Genetic EvaluationJoshua B. Max, Victoria M. Raymond, Richard S. Kwon, Elena M. Stoffel

Background: The benefit and optimal modality of pancreatic cancer (PC) screening in highrisk individuals is unclear. Methods: Individuals presenting to the University of MichiganCancer Genetics clinic between January 2009 and December 2011 who enrolled in theCancer Genetics Registry were reviewed and classified as high risk pancreatic cancer (HRPC)individuals eligible for screening if they met any of the following criteria: first-degree relativesof patients with familial PC (defined as two first-degree relatives with PC) OR diagnosis ofa hereditary cancer syndrome with increased risk for PC including Peutz-Jeghers syndrome,familial atypical multiple mole melanoma syndrome (FAMMM), and Lynch syndrome ORhereditary breast and ovarian cancer with PC in ≥1 1st or 2nd degree relative. Records werereviewed to quantify uptake, modality and outcomes of PC screening. Focal pancreaticlesions (FPLs) were defined as cystic or solid lesions, dilated main pancreatic duct or dilatedside branches. Results: Forty-six individuals met eligibility criteria for PC screening (familialPC relatives: N=28; hereditary cancer syndromes: N=18). Twenty of 46 individuals (43%)underwent screening, including 19 familial PC relatives (95%) and one individual withFAMMM. Ten individuals (50%) were screened by .1 modality. Reasons for deferredscreening included young age (N=5), concerns about insurance coverage (N=1), plans todiscuss screening with outside/primary physicians (N=2) and prior unfavorable experiencewith endoscopy (N=1) (unknown or lost to follow up: N=15). Screened individuals had anaverage age of 59 years (age range 35 to 78); 45% were female. Fourteen of 20 screenedindividuals underwent serial exams (≥2 exams at least six months apart) with average followup of 40.1 months. Six of 20 (30%) screened individuals had an FPL, including subcentimetercyst(s) (N=4) and dilated pancreatic duct side branches (N=2). Endoscopic ultrasound (EUS)was more likely than MRI to detect any pancreatic abnormality, defined as FPLs ± pancreaticparenchymal abnormalities (86% v 20%; p=0.0005). However there was no statisticallysignificant difference between EUS and MRI in detecting FPLs (43% v 20%; p=0.14). Ofsix individuals with FPLs, two had focal lesions detected on baseline exam and four hadFPLs noted only on subsequent exam. No individuals underwent surgery. Conclusions:Among HRPC individuals presenting for genetic evaluation, fewer than half engaged in PCscreening, with familial PC relatives representing the majority of those screened. Abnormalexams were common, though detected lesions were small and none required surgical resec-tion. Most individuals with FPLs had lesions noted only on follow up exam, suggesting arole for repeat screening following negative baseline exam.

Mo1203

Comparison of Maternal Food Elimination Diet and Hypoallergenic Formulafor the Treatment of Allergic Colitis in Exclusively Breastfed InfantsMaridine Co, Mohammad El-Baba

Background: Allergic Colitis (AC), which presents with hematochezia, may result fromhypersensitivity to cow's milk protein even in exclusively breastfed (EBF) infants throughthe excretion of dietary proteins in the breast milk from the maternal diet. Maternal foodelimination (MFE) diet may be equally effective, compared to treatment with expensivehypoallergenic formula (HF). There are only few studies comparing MFE to HF. Aim: Tocompare the treatment outcomes of MFE versus HF in exclusively breastfed infants withAC. Methods: We analyzed a prospectively-maintained database of patients with hemato-chezia from AC. We included healthy, full-term EBF infants (ages 0-6 months). The patientswere analyzed by group, based on the intervention (MFE vs. HF). The two groups werecompared in terms of their baseline characteristics, clinical parameters and number of patientswith resolution of hematochezia. Data was analyzed using non-parametric statistics. Results:There were 34 patients that met the inclusion criteria. The number of infants who receivedMFE (n=17) and HMF (n=17) were even by chance. Comparison of baseline characteristicsof patients treated by MFE or HF is presented in Table 1. There were no significant differencesin the baseline characteristics between MFE and HF patients in terms of age, gender, racialdistribution, hemoglobin levels, presence of other allergic conditions and eosinophil count.All had resolution of rectal bleeding. Median follow-up time was 5.34 months (mos.) (range:0-17). The median time for hematochezia (gross or occult bleeding) to resolve was 2.0 mos.(1.0-3.5) for the MFE group and 1.75 mos. (0.8-5.0) for the HF group (p=0.56). The medianage at resolution of hematochezia after initiation of intervention in the MFE group was 3.5mos. (1.5-6.8) and 3.0 mos. (1.3-6.0) in the HF group (p=0.51). Conclusion: In our cohortof patients, there was no difference in the outcomes of MFE as compared to HF for thetreatment of AC. Baseline characteristics and clinical parameters were equal between groups.Maternal food elimination diet of cow's milk appears to be an equally effective treatmentas compared to expensive use of hypoallergenic milk formula.Table1. Baseline Characteristics of Patients with Allergic Colitis by Treatment Group

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