Mo1190 Prevalence and Characteristics of Serrated Lesions in Individuals Undergoing Primary...
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AGA Abstracts 16), were 3.7 for CRCs (95%CI= 2.8 to 4.6, p ,.0001 vs. SNADs), 2.3 for CAs (95%CI= 1.7 to 3.0, p,.0001 vs. SNADs), 1.3 for LPGDs (95%CI= 0.8 to 1.8, p=.0001 vs. SNADs), and 0.3 for SNADs (95%CI= 0.2 to 0.5), respectively. Conclusion: Fecal DNA methylation strategy can robustly detect a variety of gastrointestinal tumors, including pancreatic cancers. Our improved fecal DNA methylation assay provides an effective and promising tool for the non-invasive screening of not only for CRC but also for LPGDs, highlighting its tremen- dous clinical utility in reducing the mortality and morbidity associated with these malignan- cies. Mo1187 Can Endoscopists Correctly Predict Polyp Histopathology in FIT Based Screening? Inge Stegeman, Sascha C. van Doorn, Rosalie C. Mallant-Hent, Marco W. Mundt, Paul Fockens, Patrick M. Bossuyt, Evelien Dekker Background Screening would be more efficient and cost-effective if polyps were accurately diagnosed on-site by the endoscopist. Discarding these lesions without histopathologic evaluation would reduce time and costs for a final diagnosis. The accuracy of optical diagnosis of endoscopists is compared with the histopathological diagnosis in a screening setting. Methods Data were collected in the third round of a FIT-based CRC screening pilot program in the Netherlands, in which 10,050 average risk individuals were invited to participate in a third round of FIT-based CRC screening. Participants were between 50 and 75 years of age. In this study, 318 FIT-positives underwent colonoscopy with Olympus (160 and 180 series) endoscopes without (virtual) chromoendoscopy. Endoscopists in this study had no special training in polyp assessment. They made an on-site diagnosis of all detected lesions and classified these as a hyperplastic polyp, adenoma or carcinoma. All lesions were subse- quently sent for histopathology, which was used as reference standard. We calculated the sensitivity and specificity for each category, as well as the overall accuracy. Results Colonosco- pies were performed by 24 endoscopists in two hospitals. Of these, 259 (74%) were performed by 8 endoscopists. In the 318 patients with a positive FIT, a total of 839 lesions were detected. These were classified by the pathologist as 185 hyperplastic polyps, 523 adenomas and 17 carcinomas (39 serrated adenomas excluded). Optical diagnosis was correct for 460 of 523 adenomas (sensitivity 88% and specificity of 48%). For hyperplastic polyps, optical diagnosis was correct in 74 of 185 (sensitivity 40% and specificity 14%). Of 17 carcinomas, 12 were correctly diagnosed by the endoscopist (sensitivity 71%, specificity 99%). Classifying the cancers into AJJC stadia, 7 were stage I, of which 2 were correctly identified (sensitivity 29%, specificity 99%). In stages II and III, all cancers were correctly diagnosed by the endoscopists. Conclusion In a FIT-based screening setting in routine practice, accuracy of optical diagnosis with regular white light endoscopy was suboptimal, especially for hyperplas- tic polyps and stage I cancers. This suboptimal sensitivity suggests that histopathology for lesions detected at colonoscopy for repetitive FIT-based colorectal cancer screening should not be omitted. Mo1188 High-Risk Group Targeting Colorectal Cancer Screening May Be More Adequate for Countries With Lower Incidence Compared With Average-Risk Population Screening: The Montenegro Experience Milutin M. Bulajic, Brigita D. Smolovic, Nikola Panic, Miodrag Radunovic, Maurizio Zilli, Marco Marino, Aleksandra R. Pavlovic Markovic, Zoran Krivokapic, Mirko Bulajic, Thomas Rösch Introduction: Colorectal cancer (CRC) screening has been demonstrated to be effective in randomized trials when using fecal occult blood test (FOBT) and sigmoidoscopy, while colonoscopy screening is based on indirect evidence only. We compared the outcomes of two different colonoscopic screening approaches in a small country (Montenegro, 650.000 inhabitants) with a CRC incidence lower than on European average (23/100.000). Patients and methods: Two structured invitation programs were compared with regards to compliance and neoplasia yield: 1) a 6 year program (2004-2010) focused on 1st degree relatives of CRC patients (diagnosed from 1995-2010 in 2 hospitals, n=206), inviting them for colonoscopy; 2) an invitation program for FOBT (immunological qualitative FOBT, followed by colonoscopy if positive) conducted in the University hospital for one year 2010/11 on 2760 randomly selected average-risk persons with the age 50-74 years, living in the municipality of Danilov- grad (target population estimated to be approximately 4500). Results: Of 710 1st degree relatives of CRC patients who were approached (not previously subjected to any screening tests), 540 presented for colonoscopy (76% uptake). Overall, 31 were diagnosed with a cancer, 58 with advanced adenoma (AA) and 151 with adenoma in general. In the general screening program 2760 person have been invited, 920 finally underwent FOBT (33 % uptake) and colonoscopy was performed in all 95 positive cases (10.3%); 6 cancers was found in 5 pts (one have had two cancers), 19 have been diagnosed with AA and 26 with any adenomas. The risk-targeted screening program had a yield for cancers bigger than the general screening program in also per invited and eligible persons analyses (respectively 31/ 710 (4, 3%) and 31/540 (5, 74%) vs. 5/2760 (0, 2%) and 5/920 (0, 54%)). Yield for AA and adenomas in general were also bigger in risk-targeted screening. Conclusions: In a low incidence country with limited resources it may be advisable to start with CRC screening targeted to risk groups. Mo1189 The Use of a New Stool Test M2-PK in the Diagnosis of Colorectal Cancer: A Case-Control Study Joseph J. Y. Sung, Thomas Y. Lam, Simon Ng, Janet F. Lee, Jessica Ching, Yee Kit Tse, Martin C. Wong, Francis Chan, Joachim Hevler Background. Fecal levels of tumor M2-PK, an isoform of a glycoltic enzyme pyruvate kinase (PK), are found to be significantly higher in patients with colorectal cancer than healthy subject (Koss et al. Colorectal Dis 2007). There is also evidence of suggest M2-PK is elevated S-602 AGA Abstracts in large polyps and correlated with tumor staging. Aim. This is a case-control study to evaluate the efficacy of M2-PK stool test in diagnosing colorectal cancer. Method. Patients diagnosed to have colorectal cancer (CRC) and asympatomatic (Control) subjects (1:2 ratio) were enrolled in this study. Single stool samples were collected prior to surgery for CRC or colonoscopy for controls and stored at -20°C. M2-PK stool test (Alere Inc, San Diego, USA) were performed in a blinded manner and correlated with diagnosis or colonoscopy findings. If M2-PK test result is positive but colonoscopy showed no abnormality in control subjects, M2-PK were repeated and gastroscopy plus colonoscopy were offered to detect gastrointestinal malignancy. Result. 70 CRC and 161 Controls were recruited in this interim analysis. The mean age (SD) and male gender (%) of the CRC and Control groups were 65.5 (10.7) years vs 58.2 (5.2) years respectively and 64.3% vs 47.2% respectively. The CRC staging of CRC are shown in Table 1. The sensitivity of M2-PK in detecting CRC is 78.6% (95%CI: 66.8-87.1%), specificity is 96.3% (95%CI: 91.7-98.5%), positive predictive value is 90.2% (95%CI: 79.1-95.9%) and negative predictive value is 91.2% (95%CI: 85.6- 94.8%). The sensitivity of M2-PK stool test in detecting CRC in proximal colon is 64.3% (95%CI: 35.6-86%) and in distal colon is 82.1% (69.2-90.7%). Conclusion. M2-PK stool test is a promising test for detection of colorectal cancers. A population-based test is warranted. Table 1. M2-PK Test Results accroding to CRC Staging Mo1190 Prevalence and Characteristics of Serrated Lesions in Individuals Undergoing Primary Screening Colonoscopy Yark Hazewinkel, Thomas R. de Wijkerslooth, Esther M. Stoop, Patrick M. Bossuyt, Katharina Biermann, Marc J. van de Vijver, Paul Fockens, Monique E. van Leerdam, Ernst J. Kuipers, Evelien Dekker INTRODUCTION Serrated lesions comprise a heterogeneous group of polyps with different premalignant potential that are further subdivided into hyperplastic polyps (HPs), sessile serrated adenomas/polyps (SSA/Ps) and traditional serrated adenomas (TSAs). Data on preva- lence rates and characteristics of different serrated subtypes are scarce. The aim of the current study was to determine the prevalence and to specify polyp characteristics of the different serrated subtype lesions in a large cohort of healthy individuals undergoing primary screening colonoscopy. METHODS Data were collected from subjects who participated in the random- ized, multicenter Colonoscopy or Colonography for screening (COCOS) trial. Screen-Naïve individuals, aged 50-75 years, were randomly selected and invited to undergo primary screening by colonoscopy. Colonoscopies were performed at two tertiary referral medical institutions by expert endoscopists (individual experience . 1000 colonoscopies). Bowel preparation was scored using the Ottawa scale ranging from excellent (score 0) to very poor (score 14). The proximal colon was defined as proximal to the splenic flexure. Tissue specimens were evaluated by one of the two study gastrointestinal pathologists. Serrated polyps were classified as HPs, SSA/Ps or TSAs based on criteria recently incorporated in the WHO classification for serrated polyps. The prevalence rate was defined as the proportion of screened subjects in whom at least one serrated lesion was found. Univariable and multivariable logistic regression analysis were performed to identify associations between patients' age and gender, and presence of serrated subtype lesions. RESULTS A total of 1,426 subjects (51% male) with a median age of 60 years (IQR 55-65) underwent a colonoscopy. Unadjusted cecal intubation rate was 98.7%, median withdrawal time after subtracting polypectomy time was 10 minutes (IQR 8-15) and the median Ottawa bowel preparation score was 5 (IQR 3-8). One or more adenomas were detected in 29% (419/1426) of individuals. The prevalence of HPs, SSA/Ps and TSAs was 24% (339/1426), 4.8% (68/1426) and 0.1% (1/1426), respectively. SSA/Ps comprised 7% (111/1521) of all histopathological classified polyps, 15% (111/744) of all serrated polyps and 48% (34/71) of all proximal serrated lesions larger than 5 mm (Figure 1). Multivariable analysis, adjusted for quality of bowel preparation, showed that neither patient age (OR 0.99 95% CI 0.95-1.03) nor male gender (OR 1.07 0.95% CI 0.65-1.75) was independently associated with the presence of SSA/Ps. CONCLUSIONS Serrated polyps, including SSA/Ps, are frequently encountered in a primary colonoscopy screening program. Endoscopists should be aware of these lesions and should acquire sufficient competence in recognizing and removing them. Figure 1. Ratio between HP and SSA/P histology stratified per size group and colonic location.
Transcript of Mo1190 Prevalence and Characteristics of Serrated Lesions in Individuals Undergoing Primary...
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s16), were 3.7 for CRCs (95%CI= 2.8 to 4.6, p ,.0001 vs. SNADs), 2.3 for CAs (95%CI=1.7 to 3.0, p,.0001 vs. SNADs), 1.3 for LPGDs (95%CI= 0.8 to 1.8, p=.0001 vs. SNADs),and 0.3 for SNADs (95%CI= 0.2 to 0.5), respectively. Conclusion: Fecal DNA methylationstrategy can robustly detect a variety of gastrointestinal tumors, including pancreatic cancers.Our improved fecal DNA methylation assay provides an effective and promising tool forthe non-invasive screening of not only for CRC but also for LPGDs, highlighting its tremen-dous clinical utility in reducing the mortality and morbidity associated with these malignan-cies.
Mo1187
Can Endoscopists Correctly Predict Polyp Histopathology in FIT BasedScreening?Inge Stegeman, Sascha C. van Doorn, Rosalie C. Mallant-Hent, Marco W. Mundt, PaulFockens, Patrick M. Bossuyt, Evelien Dekker
Background Screening would be more efficient and cost-effective if polyps were accuratelydiagnosed on-site by the endoscopist. Discarding these lesions without histopathologicevaluation would reduce time and costs for a final diagnosis. The accuracy of optical diagnosisof endoscopists is compared with the histopathological diagnosis in a screening setting.Methods Data were collected in the third round of a FIT-based CRC screening pilot programin the Netherlands, in which 10,050 average risk individuals were invited to participate ina third round of FIT-based CRC screening. Participants were between 50 and 75 years ofage. In this study, 318 FIT-positives underwent colonoscopy with Olympus (160 and 180series) endoscopes without (virtual) chromoendoscopy. Endoscopists in this study had nospecial training in polyp assessment. They made an on-site diagnosis of all detected lesionsand classified these as a hyperplastic polyp, adenoma or carcinoma. All lesions were subse-quently sent for histopathology, which was used as reference standard. We calculated thesensitivity and specificity for each category, as well as the overall accuracy. Results Colonosco-pies were performed by 24 endoscopists in two hospitals. Of these, 259 (74%) were performedby 8 endoscopists. In the 318 patients with a positive FIT, a total of 839 lesions weredetected. These were classified by the pathologist as 185 hyperplastic polyps, 523 adenomasand 17 carcinomas (39 serrated adenomas excluded). Optical diagnosis was correct for 460of 523 adenomas (sensitivity 88% and specificity of 48%). For hyperplastic polyps, opticaldiagnosis was correct in 74 of 185 (sensitivity 40% and specificity 14%). Of 17 carcinomas,12 were correctly diagnosed by the endoscopist (sensitivity 71%, specificity 99%). Classifyingthe cancers into AJJC stadia, 7 were stage I, of which 2 were correctly identified (sensitivity29%, specificity 99%). In stages II and III, all cancers were correctly diagnosed by theendoscopists. Conclusion In a FIT-based screening setting in routine practice, accuracy ofoptical diagnosis with regular white light endoscopy was suboptimal, especially for hyperplas-tic polyps and stage I cancers. This suboptimal sensitivity suggests that histopathology forlesions detected at colonoscopy for repetitive FIT-based colorectal cancer screening shouldnot be omitted.
Mo1188
High-Risk Group Targeting Colorectal Cancer Screening May Be MoreAdequate for Countries With Lower Incidence Compared With Average-RiskPopulation Screening: The Montenegro ExperienceMilutin M. Bulajic, Brigita D. Smolovic, Nikola Panic, Miodrag Radunovic, Maurizio Zilli,Marco Marino, Aleksandra R. Pavlovic Markovic, Zoran Krivokapic, Mirko Bulajic,Thomas Rösch
Introduction: Colorectal cancer (CRC) screening has been demonstrated to be effective inrandomized trials when using fecal occult blood test (FOBT) and sigmoidoscopy, whilecolonoscopy screening is based on indirect evidence only. We compared the outcomes oftwo different colonoscopic screening approaches in a small country (Montenegro, 650.000inhabitants) with a CRC incidence lower than on European average (23/100.000). Patientsand methods: Two structured invitation programs were compared with regards to complianceand neoplasia yield: 1) a 6 year program (2004-2010) focused on 1st degree relatives of CRCpatients (diagnosed from 1995-2010 in 2 hospitals, n=206), inviting them for colonoscopy; 2)an invitation program for FOBT (immunological qualitative FOBT, followed by colonoscopyif positive) conducted in the University hospital for one year 2010/11 on 2760 randomlyselected average-risk persons with the age 50-74 years, living in the municipality of Danilov-grad (target population estimated to be approximately 4500). Results: Of 710 1st degreerelatives of CRC patients who were approached (not previously subjected to any screeningtests), 540 presented for colonoscopy (76% uptake). Overall, 31 were diagnosed with acancer, 58 with advanced adenoma (AA) and 151 with adenoma in general. In the generalscreening program 2760 person have been invited, 920 finally underwent FOBT (33 %uptake) and colonoscopy was performed in all 95 positive cases (10.3%); 6 cancers wasfound in 5 pts (one have had two cancers), 19 have been diagnosed with AA and 26 withany adenomas. The risk-targeted screening program had a yield for cancers bigger than thegeneral screening program in also per invited and eligible persons analyses (respectively 31/710 (4, 3%) and 31/540 (5, 74%) vs. 5/2760 (0, 2%) and 5/920 (0, 54%)). Yield for AAand adenomas in general were also bigger in risk-targeted screening. Conclusions: In a lowincidence country with limited resources it may be advisable to start with CRC screeningtargeted to risk groups.
Mo1189
The Use of a New Stool Test M2-PK in the Diagnosis of Colorectal Cancer: ACase-Control StudyJoseph J. Y. Sung, Thomas Y. Lam, Simon Ng, Janet F. Lee, Jessica Ching, Yee Kit Tse,Martin C. Wong, Francis Chan, Joachim Hevler
Background. Fecal levels of tumor M2-PK, an isoform of a glycoltic enzyme pyruvate kinase(PK), are found to be significantly higher in patients with colorectal cancer than healthysubject (Koss et al. Colorectal Dis 2007). There is also evidence of suggest M2-PK is elevated
S-602AGA Abstracts
in large polyps and correlated with tumor staging. Aim. This is a case-control study toevaluate the efficacy of M2-PK stool test in diagnosing colorectal cancer. Method. Patientsdiagnosed to have colorectal cancer (CRC) and asympatomatic (Control) subjects (1:2 ratio)were enrolled in this study. Single stool samples were collected prior to surgery for CRCor colonoscopy for controls and stored at -20°C. M2-PK stool test (Alere Inc, San Diego,USA) were performed in a blinded manner and correlated with diagnosis or colonoscopyfindings. If M2-PK test result is positive but colonoscopy showed no abnormality in controlsubjects, M2-PK were repeated and gastroscopy plus colonoscopy were offered to detectgastrointestinal malignancy. Result. 70 CRC and 161 Controls were recruited in this interimanalysis. The mean age (SD) and male gender (%) of the CRC and Control groups were65.5 (10.7) years vs 58.2 (5.2) years respectively and 64.3% vs 47.2% respectively. TheCRC staging of CRC are shown in Table 1. The sensitivity of M2-PK in detecting CRC is78.6% (95%CI: 66.8-87.1%), specificity is 96.3% (95%CI: 91.7-98.5%), positive predictivevalue is 90.2% (95%CI: 79.1-95.9%) and negative predictive value is 91.2% (95%CI: 85.6-94.8%). The sensitivity of M2-PK stool test in detecting CRC in proximal colon is 64.3%(95%CI: 35.6-86%) and in distal colon is 82.1% (69.2-90.7%). Conclusion. M2-PK stooltest is a promising test for detection of colorectal cancers. A population-based test is warranted.Table 1. M2-PK Test Results accroding to CRC Staging
Mo1190
Prevalence and Characteristics of Serrated Lesions in Individuals UndergoingPrimary Screening ColonoscopyYark Hazewinkel, Thomas R. de Wijkerslooth, Esther M. Stoop, Patrick M. Bossuyt,Katharina Biermann, Marc J. van de Vijver, Paul Fockens, Monique E. van Leerdam, ErnstJ. Kuipers, Evelien Dekker
INTRODUCTION Serrated lesions comprise a heterogeneous group of polyps with differentpremalignant potential that are further subdivided into hyperplastic polyps (HPs), sessileserrated adenomas/polyps (SSA/Ps) and traditional serrated adenomas (TSAs). Data on preva-lence rates and characteristics of different serrated subtypes are scarce. The aim of the currentstudy was to determine the prevalence and to specify polyp characteristics of the differentserrated subtype lesions in a large cohort of healthy individuals undergoing primary screeningcolonoscopy. METHODS Data were collected from subjects who participated in the random-ized, multicenter Colonoscopy or Colonography for screening (COCOS) trial. Screen-Naïveindividuals, aged 50-75 years, were randomly selected and invited to undergo primaryscreening by colonoscopy. Colonoscopies were performed at two tertiary referral medicalinstitutions by expert endoscopists (individual experience . 1000 colonoscopies). Bowelpreparation was scored using the Ottawa scale ranging from excellent (score 0) to very poor(score 14). The proximal colon was defined as proximal to the splenic flexure. Tissuespecimens were evaluated by one of the two study gastrointestinal pathologists. Serratedpolyps were classified as HPs, SSA/Ps or TSAs based on criteria recently incorporated in theWHO classification for serrated polyps. The prevalence rate was defined as the proportionof screened subjects in whom at least one serrated lesion was found. Univariable andmultivariable logistic regression analysis were performed to identify associations betweenpatients' age and gender, and presence of serrated subtype lesions. RESULTS A total of 1,426subjects (51% male) with a median age of 60 years (IQR 55-65) underwent a colonoscopy.Unadjusted cecal intubation rate was 98.7%, median withdrawal time after subtractingpolypectomy time was 10 minutes (IQR 8-15) and the median Ottawa bowel preparationscore was 5 (IQR 3-8). One or more adenomas were detected in 29% (419/1426) ofindividuals. The prevalence of HPs, SSA/Ps and TSAs was 24% (339/1426), 4.8% (68/1426)and 0.1% (1/1426), respectively. SSA/Ps comprised 7% (111/1521) of all histopathologicalclassified polyps, 15% (111/744) of all serrated polyps and 48% (34/71) of all proximalserrated lesions larger than 5 mm (Figure 1). Multivariable analysis, adjusted for quality ofbowel preparation, showed that neither patient age (OR 0.99 95% CI 0.95-1.03) nor malegender (OR 1.07 0.95% CI 0.65-1.75) was independently associated with the presence ofSSA/Ps. CONCLUSIONS Serrated polyps, including SSA/Ps, are frequently encountered ina primary colonoscopy screening program. Endoscopists should be aware of these lesionsand should acquire sufficient competence in recognizing and removing them.
Figure 1. Ratio between HP and SSA/P histology stratified per size group and colonic location.
