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Mo1949 Patterns of Use of CT Colonography in Medicare Beneficiaries
Mo1949
results obtained from the colonoscopy group, according to the criteria proposed in the UK Flexible Sigmoidoscopy Trial for colonoscopy referral. The main outcomes were first, rate of detection of proximal serrated lesions defined as sessile serrated polyp or hyperplastic polyp of any size (SP+HP) and secondly, proximal serrated polyp of any size or hyperplastic polyp ≥ 10mm (SP+HP10), both proximal to splenic flexure. Results: Proximal serrated lesions (SP+HP) were observed in 329 of 5059 (6.5%) individuals, whereas proximal serrated polyp of any size or hyperplastic polyp ≥ 10mm (SP+HP10) were detected only in 88 subjects (1.7%). pSP+HP and pSP+HP10 were detected in 47 subjects (0.9%) and 16 subjects (0.3%), in the sigmoidoscopy simulation (odds ratio for sigmoidoscopy 0.13; 95% CI 0.090.18; p <0.0001 and 0.17; 95% CI 0.1;-0.29, p <0.0001, respectively. The number of individuals needed to refer for colonoscopy to detect one pSP+HP and one pSP+HP10 was 7 (95% CI 5-9) and 20 (95% CI 12-32), respectively. Sensitivity of sigmoidoscopy for pSP+HP was lower in women, from 14.3% in men aged 60-69 years to 3.9% in women aged 50-59 years. Sigmoidoscopy did not detect any of the 11 and 18 women's, aged 6069 and 50-59 years, respectively, with a pSP+HP10. Conclusions: Sigmoidoscopy-based strategies detect fewer individuals with proximal serrated lesions. Performance of sigmoidoscopy was lower in women, especially those aged 50-59 years.
AGA Abstracts
Patterns of Use of CT Colonography in Medicare Beneficiaries Michelle Chan, Tzuyung D. Kou, Gregory S. Cooper Background: CT colonography (CTC) emerged as a viable alternative screening test for colorectal cancer (CRC) and is recommended by the US Multisociety Task Force. Prior to 2009, it was used for both primary screening as well as a follow-up to incomplete colonoscopy. However, in May 2009, the Centers for Medicare and Medicaid Services (CMS) determined that there was not sufficient evidence for the use of CTC as a screening test and would no longer reimburse CTC if it is used as screening for CRC. In this study, we assess the patient characteristics and indications for CTC after 2009. Methods: We performed a cross-sectional analysis for receipt of CTC on a 5% random sample of physician and outpatient Medicare claims from 2010-2012 for beneficiaries enrolled in fee-for-service plans. Demographics, comorbidity, and geographic data were collected. To assess indications and outcomes of CTC, we searched the claims 6 months prior to and after CTC for the use of colonoscopy. Results: In our sample, a total of 1580 Medicare beneficiaries underwent CTC. The rate of CTC use was 0.03% from 2010 to 2012, with no difference between the years (p=0.34). The use of CTC was highest among individuals aged 80 and older, women and Caucasians (p<0.001 for all comparisons). There was higher usage in individuals with Charlson comorbidity score of 1 to 3, compared to those with scores of 0 and greater than 3 (p<0.001). Rates were highest in the Northeast and Midwest (p<0.001). Among those who underwent CTC, 26.6% had a prior colonoscopy. Six months after CTC, 28.8% had a follow-up colonoscopy, which was more common among patients without a previous colonoscopy (35.1%) than with a previous colonoscopy (11.5%) (p<0.001). Conclusions: Following the decision against routine reimbursement for CTC, it was used in only 0.03% of older Medicare beneficiaries. Despite its recognized indication for follow-up to incomplete colonoscopy, only a minority had claims for recent colonoscopy. Further studies should examine the clinical outcomes and findings among patients who undergo CTC.
Mo1952 Lower Risk of High Risk Adenoma (HRA) and Colorectal Cancer (CRC) Among Patients With a Previous Negative Result From a Fecal Immunochemical Test (FIT) for Colorectal Cancer. Data on Second Round Screening Xavier Bessa, Cristina Alvarez-Urturi, Cristina Hernandez, Josep M Augé, Jaume Grau, Andrea Buron, Francesc Macià, Laura Carot, Antoni Castells, Montserrat Andreu Screening for colorectal cancer by FIT is based on consecutive rounds to detect precursor lesions or CRC in early stages. Data on consecutive rounds of FIT screening are limited and based mostly on small population studies Aim: We assessed the final data regarding positivity predictive values (PPVs) for high risk adenomas (HRA), low risk adenomas (LRA) and CRC among patients with a previous negative result from a FIT. Methods: Data were collected from 2 rounds of FIT screening in average-risk persons (50 to 70 years old). The PPV for HRA and CRC were compared among the first-round (FR group) participants and secondround (SR group) participants with a previous negative FIT result. We also evaluated those patients participant in the second round not previously participants in first round (first screening in the second round) (FS group). Definitions: HRA: advanced adenoma or three or more adenoma. Results: The rate of positive results from FIT was significantly superior in the first vs. second round screening (6.2% vs. 4.7%, p< 0.0001) and very similar to the FS group (6.4%, p<0.32, respect to FR). Data comparing all participants in the FR, SR and FS groups who tested FIT positive and were eligible for colonoscopy were compared (4,182 vs. 2281 vs 1323 colonoscopy studies performed, respectively). A significant decrease in the PPV was observed for CRC between the FR and SR (6.3% to 3.3%; p<0.0001) and similar to the FS group (6.3% to 6.7, p<0.65, respect to FR). A significant decrease in the PPV for HRA were observed between FR vs SR (41.2% to 33.2%; p<0.0001) but also respect to the FS group (36.0%, p<0.001, respect to FR).There were no significant differences in stages (I+II vs. III+IV) of CRC detected in the three groups (31.4%, 30.6%, and 22.6, respectively for stage III+IV) No differences were observed between three groups for proximal location (21.4%, 30.6% and 22.9%, for FR, SR and FS groups, respectively. Although not achieving statistical significance, proximal CRC were more frequent in the FR respect to SR (21.4% vs. 30.6%, p<0.07). Conclusions: In our population-based CRC screening program the rate of positive results from FIT decrease after a first round, and PPVs of FIT for HRA and CRC are significantly lower among second-round participants who tested negative in the first round. No differences were observed in CRC stage but a tendency to proximally location of CRC on second round screening for CRC were observed
Mo1950 Comparison of One Versus Two Fecal Immunochemical Tests (FIT) in the Detection of Colorectal Neoplasia in a Population-Based Colorectal Cancer Screening Program Sarvenaz Moosavi, Laura Gentile, Gondara Lovedeep, Colleen McGahan, Robert A. Enns, Jennifer J. Telford Objective: To determine the predictive value of two versus one abnormal FIT in the detection of colorectal neoplasia in a Canadian population Methods: Three BC communities were enrolled in a colorectal cancer screening pilot program from January 2009 to April 2013 using a 2 sample quantitative biennial FIT (cut-off 100 ng/ ml) with follow-up colonoscopy for abnormal FITs. All data was collected prospectively, and entered into a central database including patient demographics, FIT results, colonoscopy quality indicators, pathology results, and cancer stage. Patient inclusion criteria for this study are: 1) both FIT kits were completed satisfactorily, 2) one or both of the two FITs is abnormal, and 3) colonoscopy was completed. High-risk polyps were defined as adenomas > 10mm, adenomas with high grade dysplasia, villous adenomas, traditional or serrated sessile adenomas, and > 3 tubular adenomas. Low risk polyps were defined as < 3 tubular adenomas, < 10 mm in size with low grade dysplasia. For patients with multiple neoplasms, the most significant lesion is reported. The positive predictive value of one versus two abnormal FIT(s) was calculated using a weighted generalized score statistic (Kolinski et al). A two-sided 5% significance level was used. This study was approved by the ethics board at the BC Cancer Agency. Results: 17,031 average risk men and women 50-74 years of age completed at least one round of screening with FIT over the course of the pilot program. Of the 1576 patients with an abnormal FIT, 837 (53%) had a neoplasm: 37 (3%) had cancer, 426 (27%) had high risk polyps, and 374 (24%) had low risk polyps as the most significant lesions. For the detection of cancer, the positive predictive value (PPV) was 0.7% for one abnormal FIT and 6% for two abnormal FITs (p-value= 0.0002). For the detection of cancer or a high risk polyp, the PPVs were 21% and 46% for one and two abnormal FITs, respectively (p< 0.0001). For the detection of any neoplasia, PPVs were 47% for one abnormal FIT and 65% for two abnormal FITs (p <0.0001). When only the value of the first completed FIT is considered (1st FIT normal, 2nd FIT abnormal): 5 (14%) patients would have an undetected cancer, and 104 (23%) would have an undetectable high risk polyp and/or cancer. Conclusions: In this population-based study, two abnormal FITs had a significantly higher PPV for neoplasia when compared to one abnormal FIT. Whether these results would persist longterm with multiple screening rounds has yet to be determined. Screening programs would need to weigh the additional cost of two tests as well as increased colonoscopy and pathology utilization against potential benefits.
Mo1953 "SCORE" for Cardiovascular Risk: A Tool for Screening to Detect High Risk of Colorectal Neoplasia Carla J. Gargallo, Patricia Carrera, Carmelo Scarpignato, Angel Lanas INTRODUCTION: Cardiovascular (CV) disease and colorectal cancer (CRC) are important health problems worldwide and share several risk factors. Little is known about the risk of colorectal neoplasia (adenomas or CRC) among individuals at different risk for CV disease. AIMS: To evaluate: 1) the prevalence of colorectal neoplasia in an average CRC risk population according to the individual CV risk, 2) the relationship between the CV risk and type of colorectal neoplasia (non advanced adenoma, advanced adenoma and CRC). METHODS: A cross sectional study of average CRC risk individuals who received a colonoscopy at University Hospital of Zaragoza, Spain. Patients were classified into three groups of risk for developing a fatal atherosclerotic event in the next 10 years: 1) low risk 2) moderate risk and 3) high or very high risk. The classification was based on the SCORE system and on recommendations of the last "Europe Guidelines of CV disease prevention in clinical practice (version 2012)". The relationship between the 10-year risk category of CV disease and prevalence of colorectal neoplasia was analysed for trends by using χ2 test. Then, logistic regression models were used. RESULTS: 481 patients were included in this study. The mean age was 59.7 ± 11.0 years, and there were 240 men (49.9%). 10.4% of patients were diabetic and 23.5% were smokers. 178 patients (37%) had 1 or more colorectal neoplasias. The prevalence of colorectal neoplasia in patients with low CV risk, intermediate CV risk and high/very high CV risk was 5 % (4/80), 41.4 % (109/263) and 47.1% (65/138), respectively (p< 0.001). The prevalence of advanced colorectal neoplasia (advanced adenoma or CRC) was 1.2 % (1/80), 24% (63/263) and 36.2% (50/138), respectively (p< 0.001). In multivariate analyses, the moderate risk group and the high/very high risk group had a significantly increased risk of colorectal neoplasia compared with the low risk group, [Odds Ratio (OR) 9.68 (95% confidence interval (CI), 3.02-31.03)] and [OR 9.93 (95% CI, 2.5838.19)], respectively ( p=0.001 ). The high/very high risk group had a non-significantly increased risk of overall colorectal neoplasia compared with the moderate risk group [OR 1.03 (95% CI, 0. 61- 1.73), p = 0.92]. However, the high/very high risk group had a significantly increased risk of advanced colorectal neoplasia (advanced adenoma and/or
Mo1951 Rate of Detection of Serrated Lesions in Proximal Colon by Simulated Sigmoidoscopy Xavier Bessa, Cristina Alvarez-Urturi, Cristina Hernandez, Francesc Balaguer, Angel Lanas, Joaquin Cubiella, Juan Diego Morillas, Rodrigo Jover, Vicent Hernandez, Luis Bujanda, Angel Fernandez, Dolores Salas, Fernando Carballo-Alvarez, Enrique Quintero, Francisco Perez Riquelme, Laura Carot, Antoni Castells, Montserrat Andreu Screening for colorectal cancer by sigmoidoscopy benefits from the fact that distal findings predict the risk of proximal advanced neoplasms. Not all sigmoidoscopy trials have been observed a reduction in CRC-specific mortality. Major criticism of sigmoidoscopy trials is its lower ability to detect APN respect to colonoscopy. Moreover, proximal tumors may be due to the serrated pathway. No long data about rate of proximal serrated lesions detected with sigmoidoscopy strategies has been published. Aim: To determine the rate of detection of proximal serrated lesions by simulated sigmoidoscopy in a population-based multicenter, nationwide, randomized controlled trial. Methods: Asymptomatic individuals aged 50-69 years were eligible for a randomized controlled trial designed to compare colonoscopy and fecal immunochemical test (Colonprev study). Sigmoidoscopy yield was simulated from
AGA Abstracts
S-748
results obtained from the colonoscopy group, according to the criteria proposed in the UK Flexible Sigmoidoscopy Trial for colonoscopy referral. The main outcomes were first, rate of detection of proximal serrated lesions defined as sessile serrated polyp or hyperplastic polyp of any size (SP+HP) and secondly, proximal serrated polyp of any size or hyperplastic polyp ≥ 10mm (SP+HP10), both proximal to splenic flexure. Results: Proximal serrated lesions (SP+HP) were observed in 329 of 5059 (6.5%) individuals, whereas proximal serrated polyp of any size or hyperplastic polyp ≥ 10mm (SP+HP10) were detected only in 88 subjects (1.7%). pSP+HP and pSP+HP10 were detected in 47 subjects (0.9%) and 16 subjects (0.3%), in the sigmoidoscopy simulation (odds ratio for sigmoidoscopy 0.13; 95% CI 0.090.18; p <0.0001 and 0.17; 95% CI 0.1;-0.29, p <0.0001, respectively. The number of individuals needed to refer for colonoscopy to detect one pSP+HP and one pSP+HP10 was 7 (95% CI 5-9) and 20 (95% CI 12-32), respectively. Sensitivity of sigmoidoscopy for pSP+HP was lower in women, from 14.3% in men aged 60-69 years to 3.9% in women aged 50-59 years. Sigmoidoscopy did not detect any of the 11 and 18 women's, aged 6069 and 50-59 years, respectively, with a pSP+HP10. Conclusions: Sigmoidoscopy-based strategies detect fewer individuals with proximal serrated lesions. Performance of sigmoidoscopy was lower in women, especially those aged 50-59 years.
AGA Abstracts
Patterns of Use of CT Colonography in Medicare Beneficiaries Michelle Chan, Tzuyung D. Kou, Gregory S. Cooper Background: CT colonography (CTC) emerged as a viable alternative screening test for colorectal cancer (CRC) and is recommended by the US Multisociety Task Force. Prior to 2009, it was used for both primary screening as well as a follow-up to incomplete colonoscopy. However, in May 2009, the Centers for Medicare and Medicaid Services (CMS) determined that there was not sufficient evidence for the use of CTC as a screening test and would no longer reimburse CTC if it is used as screening for CRC. In this study, we assess the patient characteristics and indications for CTC after 2009. Methods: We performed a cross-sectional analysis for receipt of CTC on a 5% random sample of physician and outpatient Medicare claims from 2010-2012 for beneficiaries enrolled in fee-for-service plans. Demographics, comorbidity, and geographic data were collected. To assess indications and outcomes of CTC, we searched the claims 6 months prior to and after CTC for the use of colonoscopy. Results: In our sample, a total of 1580 Medicare beneficiaries underwent CTC. The rate of CTC use was 0.03% from 2010 to 2012, with no difference between the years (p=0.34). The use of CTC was highest among individuals aged 80 and older, women and Caucasians (p<0.001 for all comparisons). There was higher usage in individuals with Charlson comorbidity score of 1 to 3, compared to those with scores of 0 and greater than 3 (p<0.001). Rates were highest in the Northeast and Midwest (p<0.001). Among those who underwent CTC, 26.6% had a prior colonoscopy. Six months after CTC, 28.8% had a follow-up colonoscopy, which was more common among patients without a previous colonoscopy (35.1%) than with a previous colonoscopy (11.5%) (p<0.001). Conclusions: Following the decision against routine reimbursement for CTC, it was used in only 0.03% of older Medicare beneficiaries. Despite its recognized indication for follow-up to incomplete colonoscopy, only a minority had claims for recent colonoscopy. Further studies should examine the clinical outcomes and findings among patients who undergo CTC.
Mo1952 Lower Risk of High Risk Adenoma (HRA) and Colorectal Cancer (CRC) Among Patients With a Previous Negative Result From a Fecal Immunochemical Test (FIT) for Colorectal Cancer. Data on Second Round Screening Xavier Bessa, Cristina Alvarez-Urturi, Cristina Hernandez, Josep M Augé, Jaume Grau, Andrea Buron, Francesc Macià, Laura Carot, Antoni Castells, Montserrat Andreu Screening for colorectal cancer by FIT is based on consecutive rounds to detect precursor lesions or CRC in early stages. Data on consecutive rounds of FIT screening are limited and based mostly on small population studies Aim: We assessed the final data regarding positivity predictive values (PPVs) for high risk adenomas (HRA), low risk adenomas (LRA) and CRC among patients with a previous negative result from a FIT. Methods: Data were collected from 2 rounds of FIT screening in average-risk persons (50 to 70 years old). The PPV for HRA and CRC were compared among the first-round (FR group) participants and secondround (SR group) participants with a previous negative FIT result. We also evaluated those patients participant in the second round not previously participants in first round (first screening in the second round) (FS group). Definitions: HRA: advanced adenoma or three or more adenoma. Results: The rate of positive results from FIT was significantly superior in the first vs. second round screening (6.2% vs. 4.7%, p< 0.0001) and very similar to the FS group (6.4%, p<0.32, respect to FR). Data comparing all participants in the FR, SR and FS groups who tested FIT positive and were eligible for colonoscopy were compared (4,182 vs. 2281 vs 1323 colonoscopy studies performed, respectively). A significant decrease in the PPV was observed for CRC between the FR and SR (6.3% to 3.3%; p<0.0001) and similar to the FS group (6.3% to 6.7, p<0.65, respect to FR). A significant decrease in the PPV for HRA were observed between FR vs SR (41.2% to 33.2%; p<0.0001) but also respect to the FS group (36.0%, p<0.001, respect to FR).There were no significant differences in stages (I+II vs. III+IV) of CRC detected in the three groups (31.4%, 30.6%, and 22.6, respectively for stage III+IV) No differences were observed between three groups for proximal location (21.4%, 30.6% and 22.9%, for FR, SR and FS groups, respectively. Although not achieving statistical significance, proximal CRC were more frequent in the FR respect to SR (21.4% vs. 30.6%, p<0.07). Conclusions: In our population-based CRC screening program the rate of positive results from FIT decrease after a first round, and PPVs of FIT for HRA and CRC are significantly lower among second-round participants who tested negative in the first round. No differences were observed in CRC stage but a tendency to proximally location of CRC on second round screening for CRC were observed
Mo1950 Comparison of One Versus Two Fecal Immunochemical Tests (FIT) in the Detection of Colorectal Neoplasia in a Population-Based Colorectal Cancer Screening Program Sarvenaz Moosavi, Laura Gentile, Gondara Lovedeep, Colleen McGahan, Robert A. Enns, Jennifer J. Telford Objective: To determine the predictive value of two versus one abnormal FIT in the detection of colorectal neoplasia in a Canadian population Methods: Three BC communities were enrolled in a colorectal cancer screening pilot program from January 2009 to April 2013 using a 2 sample quantitative biennial FIT (cut-off 100 ng/ ml) with follow-up colonoscopy for abnormal FITs. All data was collected prospectively, and entered into a central database including patient demographics, FIT results, colonoscopy quality indicators, pathology results, and cancer stage. Patient inclusion criteria for this study are: 1) both FIT kits were completed satisfactorily, 2) one or both of the two FITs is abnormal, and 3) colonoscopy was completed. High-risk polyps were defined as adenomas > 10mm, adenomas with high grade dysplasia, villous adenomas, traditional or serrated sessile adenomas, and > 3 tubular adenomas. Low risk polyps were defined as < 3 tubular adenomas, < 10 mm in size with low grade dysplasia. For patients with multiple neoplasms, the most significant lesion is reported. The positive predictive value of one versus two abnormal FIT(s) was calculated using a weighted generalized score statistic (Kolinski et al). A two-sided 5% significance level was used. This study was approved by the ethics board at the BC Cancer Agency. Results: 17,031 average risk men and women 50-74 years of age completed at least one round of screening with FIT over the course of the pilot program. Of the 1576 patients with an abnormal FIT, 837 (53%) had a neoplasm: 37 (3%) had cancer, 426 (27%) had high risk polyps, and 374 (24%) had low risk polyps as the most significant lesions. For the detection of cancer, the positive predictive value (PPV) was 0.7% for one abnormal FIT and 6% for two abnormal FITs (p-value= 0.0002). For the detection of cancer or a high risk polyp, the PPVs were 21% and 46% for one and two abnormal FITs, respectively (p< 0.0001). For the detection of any neoplasia, PPVs were 47% for one abnormal FIT and 65% for two abnormal FITs (p <0.0001). When only the value of the first completed FIT is considered (1st FIT normal, 2nd FIT abnormal): 5 (14%) patients would have an undetected cancer, and 104 (23%) would have an undetectable high risk polyp and/or cancer. Conclusions: In this population-based study, two abnormal FITs had a significantly higher PPV for neoplasia when compared to one abnormal FIT. Whether these results would persist longterm with multiple screening rounds has yet to be determined. Screening programs would need to weigh the additional cost of two tests as well as increased colonoscopy and pathology utilization against potential benefits.
Mo1953 "SCORE" for Cardiovascular Risk: A Tool for Screening to Detect High Risk of Colorectal Neoplasia Carla J. Gargallo, Patricia Carrera, Carmelo Scarpignato, Angel Lanas INTRODUCTION: Cardiovascular (CV) disease and colorectal cancer (CRC) are important health problems worldwide and share several risk factors. Little is known about the risk of colorectal neoplasia (adenomas or CRC) among individuals at different risk for CV disease. AIMS: To evaluate: 1) the prevalence of colorectal neoplasia in an average CRC risk population according to the individual CV risk, 2) the relationship between the CV risk and type of colorectal neoplasia (non advanced adenoma, advanced adenoma and CRC). METHODS: A cross sectional study of average CRC risk individuals who received a colonoscopy at University Hospital of Zaragoza, Spain. Patients were classified into three groups of risk for developing a fatal atherosclerotic event in the next 10 years: 1) low risk 2) moderate risk and 3) high or very high risk. The classification was based on the SCORE system and on recommendations of the last "Europe Guidelines of CV disease prevention in clinical practice (version 2012)". The relationship between the 10-year risk category of CV disease and prevalence of colorectal neoplasia was analysed for trends by using χ2 test. Then, logistic regression models were used. RESULTS: 481 patients were included in this study. The mean age was 59.7 ± 11.0 years, and there were 240 men (49.9%). 10.4% of patients were diabetic and 23.5% were smokers. 178 patients (37%) had 1 or more colorectal neoplasias. The prevalence of colorectal neoplasia in patients with low CV risk, intermediate CV risk and high/very high CV risk was 5 % (4/80), 41.4 % (109/263) and 47.1% (65/138), respectively (p< 0.001). The prevalence of advanced colorectal neoplasia (advanced adenoma or CRC) was 1.2 % (1/80), 24% (63/263) and 36.2% (50/138), respectively (p< 0.001). In multivariate analyses, the moderate risk group and the high/very high risk group had a significantly increased risk of colorectal neoplasia compared with the low risk group, [Odds Ratio (OR) 9.68 (95% confidence interval (CI), 3.02-31.03)] and [OR 9.93 (95% CI, 2.5838.19)], respectively ( p=0.001 ). The high/very high risk group had a non-significantly increased risk of overall colorectal neoplasia compared with the moderate risk group [OR 1.03 (95% CI, 0. 61- 1.73), p = 0.92]. However, the high/very high risk group had a significantly increased risk of advanced colorectal neoplasia (advanced adenoma and/or
Mo1951 Rate of Detection of Serrated Lesions in Proximal Colon by Simulated Sigmoidoscopy Xavier Bessa, Cristina Alvarez-Urturi, Cristina Hernandez, Francesc Balaguer, Angel Lanas, Joaquin Cubiella, Juan Diego Morillas, Rodrigo Jover, Vicent Hernandez, Luis Bujanda, Angel Fernandez, Dolores Salas, Fernando Carballo-Alvarez, Enrique Quintero, Francisco Perez Riquelme, Laura Carot, Antoni Castells, Montserrat Andreu Screening for colorectal cancer by sigmoidoscopy benefits from the fact that distal findings predict the risk of proximal advanced neoplasms. Not all sigmoidoscopy trials have been observed a reduction in CRC-specific mortality. Major criticism of sigmoidoscopy trials is its lower ability to detect APN respect to colonoscopy. Moreover, proximal tumors may be due to the serrated pathway. No long data about rate of proximal serrated lesions detected with sigmoidoscopy strategies has been published. Aim: To determine the rate of detection of proximal serrated lesions by simulated sigmoidoscopy in a population-based multicenter, nationwide, randomized controlled trial. Methods: Asymptomatic individuals aged 50-69 years were eligible for a randomized controlled trial designed to compare colonoscopy and fecal immunochemical test (Colonprev study). Sigmoidoscopy yield was simulated from
AGA Abstracts
S-748