Colonoscopy Surveillance Guidelines Research Articles

Histopathological comparison of colorectal neoplasia or polyps development between young adults and older adults: Our experience of 735 consecutive cases and 1269 polyps

Objective: In recent decades, there has been an increase in early-onset colorectal cancer, the need to screen individuals younger than 50 years of age, and the presence of histopathological differences remains unclear. The objective of this study was to explore the occurrence of polyps in both young adults and older individuals and to examine their potential correlation with colorectal cancer. Methods: In this retrospective study conducted between July 1, 2018, and October 5, 2022, in the Pathology Laboratory, we designed a study based on the histopathological features of colorectal polyps evaluated by an experienced gastrointestinal pathologist based on the WHO 2019 classification. Results: We evaluated 735 consecutive patients who underwent colonoscopic polypectomy between July 2018 and October 2022. The prevalence of cases under the age of 50 was 13.9%, and adults over the age of 50 was 86.1%. A total of 1269 polyps were detected, 1215 (95.7%) were epithelial polyps and 145 (11.9%) were epithelial polyps under the age of 50. One hundred four conventional adenomas and four intramucosal carcinomas were detected in cases younger than 50 years. The patients in the low-risk adenoma group was 57%, and the rate of patients in the high-risk adenoma group was 14.9%. Overall, polyps were most common in the sigmoid colon and there was a statistically significant difference between detecting tubular adenomas in the sigmoid colon (P=0.04). Conclusions: Our current results confirm the detection of sporadic colorectal adenomas and advanced neoplasia in young adults.It is important to establish professional community guidelines for surveillance colonoscopy in these age groups. doi: https://doi.org/10.12669/pjms.40.6.8475 How to cite this: Koyuncuer A. Histopathological comparison of colorectal neoplasia or polyps development between young adults and older adults: Our experience of 735 consecutive cases and 1269 polyps. Pak J Med Sci. 2024;40(6):1111-1115. doi: https://doi.org/10.12669/pjms.40.6.8475 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Synchronous early rectal adenocarcinoma and neuroendocrine tumour: A treatment strategy

IntroductionSynchronous colorectal adenocarcinoma with neuroendocrine tumour (NET) are a unique combination of tumours. These may be incidental lesions, usually a histopathological diagnosis rather than a clinical diagnosis from symptoms, examination or even gross appearances.AimThis paper aims to highlight our management strategy on manging a middle-aged woman with synchronous rectal adenocarcinoma and NET.Case studyA 53-year-old woman presented with lower gastrointestinal bleeding with constitutional symptoms. Clinical examination and colonoscopy revealed a classical rectal adenocarcinoma, confirmed via biopsy. However, the final histopathology reports of the resected tumour revealed an early rectal adenocarcinoma with synchronous NET.Results and discussionWe review the relevant literature and a discussion regarding guidelines available for diagnosis, follow-up and surveillance of this rare case.ConclusionsThere are no current guidelines for surveillance colonoscopy after detecting gastrointestinal NET, particularly synchronous tumours. NET may be another colorectal cancer risk factor with similar mutations and common genetic markers. Clinicians should consider doing a colonoscopy when or if their patients are diagnosed with any gastrointestinal NET. Detection of any NET warrants a thorough evaluation of the whole colon for colorectal cancer and close surveillance so that timely management can be achieved.

Predicting Risk of Colorectal Cancer After Adenoma Removal in a Large Community-Based Setting.

Colonoscopy surveillance guidelines categorize individuals as high or low risk for future colorectal cancer (CRC) based primarily on their prior polyp characteristics, but this approach is imprecise, and consideration of other risk factors may improve postpolypectomy risk stratification. Among patients who underwent a baseline colonoscopy with removal of a conventional adenoma in 2004-2016, we compared the performance for postpolypectomy CRC risk prediction (through 2020) of a comprehensive model featuring patient age, diabetes diagnosis, and baseline colonoscopy indication and prior polyp findings (i.e., adenoma with advanced histology, polyp size ≥10 mm, and sessile serrated adenoma or traditional serrated adenoma) with a polyp model featuring only polyp findings. Models were developed using Cox regression. Performance was assessed using area under the receiver operating characteristic curve (AUC) and calibration by the Hosmer-Lemeshow goodness-of-fit test. Among 95,001 patients randomly divided 70:30 into model development (n = 66,500) and internal validation cohorts (n = 28,501), 495 CRC were subsequently diagnosed; 354 in the development cohort and 141 in the validation cohort. Models demonstrated adequate calibration, and the comprehensive model demonstrated superior predictive performance to the polyp model in the development cohort (AUC 0.71, 95% confidence interval [CI] 0.68-0.74 vs AUC 0.61, 95% CI 0.58-0.64, respectively) and validation cohort (AUC 0.70, 95% CI 0.65-0.75 vs AUC 0.62, 95% CI 0.57-0.67, respectively). A comprehensive CRC risk prediction model featuring patient age, diabetes diagnosis, and baseline colonoscopy indication and polyp findings was more accurate at predicting postpolypectomy CRC diagnosis than a model based on polyp findings alone.

How practitioner-led colonoscopy surveillance management improves productivity while saving money

Background: The British Society for Gastroenterology (BSG) guidelines for post-polypectomy and post-cancer-resection surveillance were changed in October 2020, essentially excluding a large proportion of patients awaiting a surveillance colonoscopy as they now no longer fit the criteria for surveillance. Aims: To audit the colonoscopy surveillance waiting list at the Wye Valley Trust to ascertain patient appropriateness for colonoscopy under the new BSG guidelines. Methods: A practitioner-led colonoscopy surveillance clinic led by a clinical endoscopist was set up to audit the colonoscopy surveillance waiting list of over 1200 patients. The aim was to clinically assess each patient against the guidelines and determine discharge from, or continuation of, the surveillance pathway for each patient. The patients were then offered outpatient clinic appointments where fitness was assessed and appropriate investigations were finalised. Results: Patient numbers on the colonoscopy surveillance waiting list were reduced by nearly 50%, with waiting times down to 0 weeks, by facilitating practitioner-led pre-assessment and outpatient clinics, all while saving Weston General Hospital almost £300000 in the initial 9 months. Conclusions: The new colonoscopy surveillance guidelines presented an opportunity to audit and evaluate the colonoscopy guidelines in the Wye Valley Trust. The facilitation of a clinical endoscopist committed time to implement new pre-assessment processes and outpatient clinics, this process allowed the discharge of almost 50% of patients upon the colonoscopy surveillance waiting list, it created extra colonoscopy capacity for 2 week wait and urgent colonoscopies, while generating a positive financial implication for the trust.

S1584 Risk of Colorectal Cancer With Inflammatory Bowel Disease and Primary Sclerosing Cholangitis Compared to Primary Sclerosing Cholangitis Only: A Need for Consensus on Colonoscopy Surveillance Guidelines for PSC Without IBD

S1584 Risk of Colorectal Cancer With Inflammatory Bowel Disease and Primary Sclerosing Cholangitis Compared to Primary Sclerosing Cholangitis Only: A Need for Consensus on Colonoscopy Surveillance Guidelines for PSC Without IBD

Abstract PR002: Development and validation of a risk prediction model for post-polypectomy colorectal cancer in 4 prospective US cohorts

Abstract Background: Individuals with polypectomy are still at higher risk of developing colorectal cancer than general population and are thus recommended to undergo colonoscopy surveillance for timely detection and prevention of subsequent colorectal cancer. The current clinical guidelines regarding the interval of surveillance are based on weak evidence. There is substantial overuse of surveillance colonoscopy in low-risk individuals and underuse in high-risk individuals. Effective risk stratification tools for post-polypectomy colorectal cancer (PPCRC) are lacking. Methods: Leveraging the integrated endoscopic, histopathologic and epidemiologic data in 3 population-based cohorts (Nurses’ Health Study (NHS) I, II and Health Professionals Follow-up Study (HPFS)), we developed a risk score to predict incident PPCRC among 26,744 patients with a polypectomy between 1986 and 2017. We validated the risk score in the Mass General Brigham (MGB) colonoscopy cohort of 76,603 individuals with a polypectomy between 2005 and 2017. In the MGB cohort, we used the validated natural language processing algorithms to extract detailed histopathologic data and merged them with the endoscopic and other clinical data from the electronic health record systems. The detailed protocol for the cohort development has been published (PMID: 33590405). We used Cox regression to calculate the hazard ratios (HRs) and assessed the discrimination using C-statistics and reclassification using the Net Reclassification Improvement (NRI). Results: During a median follow-up of 12.8 (IQR: 9.3, 16.7) and 5.1 (IQR: 2.7, 7.8) years in the NHS I, II/HPFS and MGB colonoscopy cohorts, we documented 220 and 241 PPCRC cases, respectively. We identified a PPCRC risk score based on 11 predictors. In the validation cohort, the risk score showed a strong association with higher risk of PPCRC (HR for high vs. low, 3.55, 95% CI, 2.59-4.88) and demonstrated a C-statistic (95% CI) of 0.75 (0.70-0.79), and was discriminatory even within the low- and high-risk polyp groups of patients (C-statistic, 0.73 and 0.71, respectively) defined by the current colonoscopy surveillance guidelines, leading to a NRI of 45% for PPCRC patients. Conclusion: We developed and validated a risk stratification model for PPCRC that can be used to guide tailored colonoscopy surveillance. Citation Format: Markus Dines Knudsen, Liang Wang, Kai Wang, Georgios Polychronidis, Paula Berstad, Kana Wu, Xiaosheng He, Dong Hang, Zhe Fang, Shuji Ogino, Andrew T. Chan, Edward L. Giovannucci, Molin Wang, Mingyang Song. Development and validation of a risk prediction model for post-polypectomy colorectal cancer in 4 prospective US cohorts [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr PR002.

S334 Geographic Diversity of Data Behind Surveillance Colonoscopy Guidelines in the United States

Introduction: The selection of an appropriate surveillance interval after colonoscopy for colorectal cancer screening can minimize unnecessary procedures while preventing the development of interval neoplasia. Both the 2020 US Multi-Society Task Force guidelines and earlier iterations incorporate international data, but not all areas of the world may be represented equally. We examined the studies cited in the US surveillance colonoscopy guidelines to determine the representation of different geographic regions. Methods: We examined studies which were incorporated into the US surveillance colonoscopy guidelines between 1997 and 2020 for the following categories: normal exam, exam with adenomas, exam with sessile serrated polyps (SSPs), and exam with hyperplastic polyps (HPs). For each category, we calculated the number of studies and total number of patients that came from each region of the world. We also examined trends in the number of studies from different region over time for each of the four categories. Results: There were 18 studies totaling 9,052,886 patients pertaining to surveillance after a normal exam, 54 studies totaling 226,730 patients for adenomas, 7 studies totaling 20,993 patients for SSPs, and 5 studies totaling 22,645 patients for HPs. Thirty-eight studies (49%) were from North America, 24 (31%) from Western Europe, 11 (14%) from East Asia, and 4 (5%) were from other regions (2 from Israel, 1 from Australia, and 1 from Argentina). The greatest number of studies in all categories came from North America, though studies from other regions increased over time (Figure). North America contributed the largest number of patients to studies on normal exams (50%) and HPs (100%), whereas Western Europe contributed the greatest number (61%) for adenomas and East Asia contributed the greatest number (51%) for SSPs. Conclusion: The number of patients included in studies on surveillance after adenomas, SSPs, and HPs were an order of magnitude less than that of a normal exam which could limit the strength of recommendations for these polyp types. Furthermore, nearly all data were drawn from patients in North America, Western Europe, or East Asia with little representation from populations in other regions. Given the multicultural nature of the US population, incorporating research from other regions of the world could improve the generalizability of current surveillance colonoscopy guidelines.Figure 1.: Distribution of studies by region on surveillance interval after colonoscopy with (A) no polyps, (B) adenomas, (C) sessile serrated polyps, and (D) hyperplastic polyps

S271 Representation of Racial Minorities in the United States Colonoscopy Surveillance Interval Guidelines

Introduction: Clinical guidelines should ideally be formulated from data representative of the population they are applicable to. However, historically many studies have had disproportionately high rates of white patient enrollment, which could lead to inequities in care for racial minorities. In this study, we examined the degree to which racial minorities were represented in the US colonoscopy surveillance guidelines. Methods: We reviewed US guidelines between 1997 and 2020 and identified all studies cited by recommendations for surveillance after a baseline colonoscopy with no polyps, adenomas, sessile serrated polyps (SSPs), and hyperplastic polyps (HPs). Each study within a meta-analysis was analyzed separately. We compared the proportion of studies reporting race to the proportion which reported sex and family history of colorectal cancer (CRC). Among studies reporting race, we calculated both the median percentage of minorities and the aggregate racial distribution of patients. Statistical testing was performed via Fisher’s exact test, and Bonferroni correction was applied for multiple comparisons. Results: We reviewed a total of 77 studies, of which 35 were from the US (Table). 18 studies (23%) reported race, compared to 73 studies (95%) which reported sex and 34 (44%) which reported family history of CRC (p < 0.001 and p = 0.006 respectively). All studies which reported race were US-based studies, thus 51% of US-based studies reported race. Among studies that reported race, the median number of minorities was 15% of the study population, ranging from a low of 12% for studies on adenomas and HPs to 30% for studies on SSPs. In aggregate, non-white patients comprised 43% of the study population for normal colonoscopies but only 9% for adenomas, 22% of for SSPs, and 15% for HPs (p < 0.001 for all pairwise comparisons). Conclusion: Most studies on colonoscopy surveillance intervals, including approximately half of US-based studies, do not report the race of study participants. Among the studies that report racial data, minority patients are underrepresented in studies of adenoma, SSP, and HP surveillance intervals compared to the US population. Underrepresentation may lead to differences in outcomes being missed, thus future research should strive to include more data from these underrepresented groups. Table 1. - Reporting of Race and Racial Distribution of Patients among Studies of Colonoscopy Surveillance Intervals Abbreviations: CRC, colorectal cancer All studies(N=77) Normal colonoscopy(N=18) Adenomas(N=54) Sessile serrated polyps(N=7) Hyperplastic polyps(N=5) Number of studies which reported: Sex, n (%) 73 (95) 16 (89) 51 (94) 7 (100) 5 (100) Family history of CRC, n (%) 34 (44) 8 (44) 24 (44) 3 (43) 3 (60) Race, n (%) 18 (23) 3 (17) 12 (22) 2 (29) 2 (40) Percentage of minority patients, median (range)* 15 (4-43) 24 (15-43) 12 (4-36) 30 (16-43) 12 (10-15) Number of patients:* White, n (%) 752,876 (58) 710,149 (57) 26,672 (91) 3,053 (78) 13,341 (85) Black, n (%) 80,528 (6) 77,510 (6) 1,020 (4) 561 (14) 1,437 (9) Asian, n (%) 155,966 (12) 155,079 (12) 295 (1) 217 (6) 375 (2) Hispanic, n (%) 144,783 (11) 144,093 (12) 309 (1) 59 (2) 322 (2) Other, n (%) 167,082 (13) 165,955 (13) 954 (3) 19 (1) 154 (1) *Among studies which reported race.

Improved Adherence of Colonoscopy Surveillance Guidelines Using an Automated Endoscopy Template to Standardize Evidence-Based Recommendations

In February 2020, the United States Multi-Society Task Force (USMSTF) updated their recommendations for follow-up interval after colonoscopy with or without polypectomy. A salient change is increasing the surveillance interval for 1-2 adenomas <10 millimeters (mm) in size from 5-10 years to 7-10 years. Amid the change in these guidelines, there was significant practice variation among gastroenterology (GI) fellows and attendings regarding adherence to the new recommendations for colonoscopy follow-up intervals. In this quality improvement study, we aimed to improve adherence to appropriate follow-up recommendations for patients undergoing screening colonoscopy with 1-2 diminutive adenomas and next colonoscopy interval based on the updated USMSTF guidelines.

The Risk of Metachronous Advanced Neoplasia After Colonoscopy in Patients Aged 40-49 Years Compared With That in Patients Aged 50-59 Years.

This study investigated the risk of metachronous advanced neoplasia (AN) after colonoscopy in individuals aged 40-49 years compared with that in individuals aged 50-59 years. A retrospective cohort study was performed among Kaiser Permanente Northern California members aged 40-59 years who had their first (index) colonoscopy in 2010-2013. Participants were followed up until death, disenrollment, AN on surveillance colonoscopy, or December 31, 2018. The risk for the development of AN was estimated using the Cox regression, adjusted for confounders. The study included 11,374 patients (2,396 aged 40-49 years and 8,978 aged 50-59 years). When comparing the 40-49 years group with the 50-59 years group, AN was detected in 2.2% vs 4.4% ( P = 0.0003) on surveillance colonoscopy after index colonoscopy finding of no adenoma, in 4.6% vs 7.0% ( P = 0.03) after a finding of nonadvanced adenoma (NAA), and in 7.9% vs 11.7% ( P = 0.06) after a finding of advanced adenoma (AA), respectively. Compared with the 50-59 years group, the 40-49 years group had a lower risk of metachronous AN when no adenoma was detected on index colonoscopy (hazard ratio [HR] 0.58; 95% confidence interval [CI] 0.39-0.83) and no difference when NAA (HR 0.84; 95% CI 0.54-1.24) or AA (HR 0.83; 95% CI 0.51-1.31) was detected. Compared with patients aged 50-59 years, patients aged 40-49 years may have a lower risk of developing metachronous AN when no adenoma is detected on index colonoscopy and a similar risk when NAA or AA is detected. These data suggest current surveillance colonoscopy guidelines may be applicable to patients aged 40-49 years who undergo colonoscopy.

Assessing the impact of the 2018 National Health and Medical Research Council polyp surveillance guidelines on compliance with surveillance intervals at two public hospitals.

Several studies have highlighted poor compliance with surveillance colonoscopy guidelines. The National Health and Medical Research Council (NHMRC) guidelines were revised in 2018 and were more complex than the previous iteration (2011). The aim of this study was to determine the impact of 2018 NHMRC polyp surveillance guidelines on compliance with colonoscopy surveillance intervals. A multicentre retrospective clinical audit was conducted between January 2020 and February 2021. Patients awaiting a colonoscopy for polyp surveillance at two public tertiary care hospitals in South Australia were included. Compliance rates of recommended polyp surveillance colonoscopy intervals after implementation of 2018 NHMRC guidelines were compared with 2011 NHMRC guidelines. The projected impact on colonoscopy bookings of the change in guideline intervals was modelled to 5 and 10 years, factoring in differences in compliance. Of 3996 patients awaiting colonoscopy services at two public hospitals in South Australia, 1984 patients (60% male, median age 61 years) were waitlisted for polyp surveillance. Overall compliance with surveillance guidelines was >60%. Implementation of the 2018 NHMRC guidelines significantly reduced compliance from 65.8% (2011 guidelines) to 50.8% (2018) (χ2 <0.001, OR 0.5). Modelling projections to 5 and 10 years demonstrated that application of the 2018 guidelines significantly increases the projected number of colonoscopy bookings per year. The revised 2018 NHMRC guidelines have resulted in significantly poorer compliance post-implementation, possibly due to their increased complexity. This has potential to increase the surveillance colonoscopy waiting list burden.

Post-polypectomy surveillance: the present and the future.

An appropriate post-polypectomy surveillance program requires the effectiveness of reducing colorectal cancer and safety. In addition, the post-polypectomy surveillance program should consider the burden of limited medical resource capacity, cost-effectiveness, and patient adherence. In this sense, a risk-stratified surveillance program based on baseline colonoscopy results is ideal. Major international guidelines for post-polypectomy surveillance, such as those from the European Union and the United States, have recommended risk-stratified surveillance programs. Both guidelines have recently been updated to better differentiate between high- and low-risk individuals. In both updated guidelines, more individuals have been downgraded to lower-risk groups that require less frequent or no surveillance. Furthermore, increased attention has been paid to the surveillance of patients who undergo serrated polyp removal. Previous guidelines in Japan did not clearly outline the risk stratification in post-polypectomy surveillance. However, the new colonoscopy screening and surveillance guidelines presented by the Japan Gastroenterological Endoscopy Society include a risk-stratified post-polypectomy surveillance program. Further discussion and analysis of unresolved issues in this field, such as the optimal follow-up after the first surveillance, the upper age limit for surveillance, and the ideal method for improving adherence to surveillance guidelines, are warranted.

Younger Patients Do Not Develop More Advanced Polyps on Surveillance Colonoscopy Than Their Index Colonoscopy When Compared With Older Patients.

Colonic polyp surveillance guidelines are based on data from patients 50 and above. Given the recent lowering for colorectal cancer (CRC) screening to age 45, the aim of this study was to assess whether existing colonic polyp surveillance guidelines are appropriate to use in younger patients. We performed a retrospective cohort study of patients who underwent 2 colonoscopies within a 10-year period. Five Risk Stratification Groups (RSG) were developed based on surveillance colonoscopy interval times recommended by the US Multi-Society Task Force (USMSTF) on CRC, and changes in RSG from index to surveillance colonoscopy were compared between 3 age cohorts-those below 45, those 45 to 49, and those 50 and above. Further analysis was performed for patients whose RSG worsened from index to surveillance colonoscopy, as this was defined as an inappropriate surveillance interval. A total of 1895 patients were included in the final analysis. A multivariate regression model showed that a worsened RSG was not significantly associated with age group, both when comparing below 45 to those 50 and above [odds ratio (OR)=0.840, 95% confidence interval (CI): 0.504-1.399, P=0.50] and when comparing those 45 to 49 to those 50 and above (OR=1.416, 95% CI: 0.905-2.216, P=0.13). Only being female was found to be statistically associated with worsened RSG after controlling for other variables (OR=0.652, 95% CI: 0.486-0.875, P<0.01). Our study found that younger cohorts of patients, both below 45 and those 45 to 49, are not statistically more likely to develop more advanced polyps necessitating a shorter time to surveillance colonoscopy compared with patients 50 years and above. This finding supports using existing colonic polyp surveillance colonoscopy guidelines that were developed for patients 50 years and above in both patients below 45 and those 45 to 49 years old.

Advanced age alone should not preclude surveillance colonoscopy in the octogenarian and older population

BackgroundAlthough the risk of colorectal cancer increases with advancing age, there remains a lack of guidelines for surveillance colonoscopy in the octogenarian and older population. Our objective is to document the diagnostic yield of surveillance colonoscopies, and to analyze adenoma characteristics, complications, and short-term survival in asymptomatic octogenarian and older patients undergoing adenoma surveillance colonoscopy. MethodsSurveillance colonoscopies performed at a tertiary level hospital colorectal surgery department between January 2010 and September 2018 were queried from a prospectively maintained institutional colonoscopy database. Patients 80 years old or older undergoing routine surveillance colonoscopy after having had an adenoma or advanced adenoma diagnosed on a prior exam were included in the study. Results604 patients were included in the study with a median age of 82 and 43% were female. Median follow-up was 52 months (range 2–110), with 511(85%) patients alive at their last available follow-up. Overall, 292 patients had at least one had adenomatous lesion and 105 (17.4%) patients had advanced adenomas. Increasing age was not associated with increased rate of sessile serrated lesions (p = 0.2) however, there was an association between increasing age and advanced adenoma rates (p = 0.01). Advanced adenomas were more commonly found to be right-sided (p = 0.02). Four asymptomatic patients were diagnosed with cancer at surveillance (0.6%). ConclusionsPatients 80 years of age or older with a previous history of colorectal adenoma(s) may have a high risk of future advanced lesions and can be considered to undergo surveillance colonoscopy.

Effect of Diminutive Adenoma with High-Grade Dysplasia on Surveillance Colonoscopy Interval

Background: Colonoscopy surveillance guidelines set the surveillance schedule based on polyp characteristics. Polyps with high-grade dysplasia (HGD) require 3 years of follow-up regardless of size. However, it is unclear whether patients with diminutive polyps (≤5 mm) with HGD have a higher risk. We evaluated the effect of diminutive adenoma with HGD on adenoma occurrence. Methods: From January 2015 to December 2017, patients who underwent index and surveillance colonoscopy were retrospectively screened. The patients were grouped into no adenoma group, low-risk (patients with ≤2 low-grade dysplasia [LGD]), diminutive HGD, and high-risk (HGD >5 mm, ≥3 adenomas) groups according to the index colonoscopy results. Each group was analyzed using logistic analysis. Results: The mean follow-up period was 22.47 months. Altogether, 610 (50.45%) patients had LGD and 152 (12.5%) had HGD. Among them, 61 (5.0%) patients had a diminutive polyp with HGD. Analysis of the risks of developing advanced adenoma in the surveillance colonoscopy showed that compared to the no adenoma group, the diminutive HGD group did not show a significant risk (odds ratio [OR] = 1.503 [0.449–5.027], p = 0.509), while the high-risk group showed a significant risk (OR = 2.044 [1.015–4.114], p = 0.045). Conclusions: Diminutive adenoma with HGD increased the risk of adenoma on surveillance colonoscopy, and in the case of advanced adenoma, the risk was increased, but it was not statistically significant.

S254 How Well Do the U.S. and European Surveillance Guidelines Discriminate High- and Low-Risk Groups: Data From the New Hampshire Colonoscopy Registry

Introduction: Surveillance colonoscopy guidelines were updated by the European Society of Gastrointestinal Endoscopy (ESGE) and the United States Multi-Society Task Force (USMSTF) for Colorectal Cancer Recommendations in 2020. Our goal was to use the New Hampshire Colonoscopy Registry (NHCR) to evaluate the ability of the USMSTF (3 year) and ESGE guidelines to discriminate high versus low risk groups for metachronous colorectal neoplasia. We also examined the impact of adding polyp specific groups from the USMSTF 5-year recommendations to the USMSTF 3-year on performance. Methods: We risk stratified NHCR patients who had an index and follow up colonoscopy at least 12 months later as per USMSTF and ESGE guidelines based on index findings. We excluded examinations that were incomplete, had poor bowel preparation, baseline CRC, IBD, or polyposis syndromes. The outcome was the metachronous risk for significant colorectal neoplasia (advanced adenomas, CRC, and large serrated polyps). The sensitivity, specificity, and c-statistic were calculated for each guideline recommendation group. The c-statistics were calculated using probabilities from a logistic regression adjusting for age, sex, and time to follow up. Results: We included 20972 patients (average age 58.8 ± 8.6, 48.1% male). The addition of villous histology to ESGE resulted in an increase in sensitivity but decrease in specificity. The addition of other polyp groups into USMSTF 3 years yielded c-statistics ranging from 0.600 to 0.611. The addition of 1-2 small SSPs into USMSTF 3 years resulted in a 4.1% increase in sensitivity, with only a 1.9% decrease in specificity (Table 1). Conclusion: The ESGE and USMSTF guidelines had similar modest c-statistics, suggesting similar discriminating ability to predicting metachronous neoplasia. This is further suggested by the similar sensitivities and specificities with the addition of villous histology into the ESGE category. Additionally, the modest c-statistics may indicate the need for further adjustment of the guidelines or use of other markers. Further examination of the USMSTF 3-year guidelines were notable for increasing sensitivities with the addition of 1-2 SSPs, suggesting that SSPs may be important predictors of future neoplasia and therefore may need further study for modifications of the guidelines. For example, perhaps 1-2 SSPs should have a 3-year interval.Table 1.: Comparison of ESGE and USMSTF guidelines for metachronous colorectal neoplasia

Prevalence of Adenomas on Surveillance Colonoscopies for Patients with a History of Colonic Polyps of Unknown Histology

Guidelines for surveillance colonoscopy depend on polyp histology. When patients present to a new healthcare system and report a personal history of "colon polyps," however, information on polyp histology is frequently unavailable. To assess adenoma prevalence in patients with a history of colonic polyps of unknown histology and to compare it to patients undergoing either screening colonoscopy or surveillance colonoscopy for known adenomatous polyps. This cohort study evaluated colonoscopies of patients ≥ 50years of age over a 14-year period at a single institution. The exposure of interest was colonoscopy indication, categorized into three groups: screening colonoscopy, surveillance colonoscopy for history of colonic polyp(s) of unknown histology, and surveillance colonoscopy for history of adenoma(s). The primary outcome was adenoma detection rate. Multivariable logistic regression was used to assess the association between colonoscopy indication and adenoma detection rate. Of 31,856 colonoscopies, the adenoma prevalence was 26.1% for patients undergoing screening colonoscopy, 32.9% for patients with a history of polyps of unknown histology, and 41.9% for patients with a history of known adenomatous polyps. Relative to screening colonoscopies, there were higher odds of adenoma detection in surveillance colonoscopies for polyps of unknown histology (aOR compared to screening 1.42, 95% CI 1.30-1.55) and even higher odds among surveillance colonoscopies for a history of adenoma (aOR compared to screening 1.89, 95% CI 1.75-2.05). The adenoma prevalence on surveillance colonoscopy for patients with polyps of unknown histology was higher than that of screening colonoscopies but lower than that of surveillance colonoscopies for patients with adenomatous polyps.

Colonoscopy screening and surveillance guidelines.

The Colonoscopy Screening and Surveillance Guidelines were developed by the Japan Gastroenterological Endoscopy Society as basic guidelines based on the scientific methods. The importance of endoscopic screening and surveillance for both detection and post-treatment follow-up of colorectal cancer has been recognized as essential to reduce disease mortality. There is limited high-level evidence in this field; therefore, we had to focus on the consensus of experts. These clinical practice guidelines consist of 20 clinical questions and eight background knowledge topics that have been determined as the current guiding principles.

Adherence to surveillance colonoscopy guidelines in patients following curative-intent colorectal cancer resection

BackgroundCurrent guidelines recommend that patients who have undergone curative-intent resection for colorectal cancer (CRC) should undergo colonoscopy one year following their surgery or at six months post-operatively if a pre-operative colonoscopy was not performed due to an obstructing lesion. We sought to determine adherence to postoperative surveillance colonoscopy guidelines in our National Cancer Institute designated comprehensive cancer center and potentially identify factors associated with non-adherence. Materials and MethodsA retrospective review of 100 patients who underwent curative-intent CRC resection was performed between 2013 and 2019. Patients were divided into two groups based upon adherence to surveillance colonoscopy guidelines. Demographic, tumor, and postoperative variables were analyzed. ResultsThe median age of all patients was 62. Fifty-seven percent of patients were male. Thirty-eight patients underwent surveillance colonoscopy in accordance with current guidelines. Sixty-two patients did not undergo surveillance colonoscopy postoperatively or did so outside of the National Comprehensive Cancer Network guidelines. Factors associated with non-adherence to surveillance colonoscopy included presence of comorbidities, albumin less than 3.5, and performance of a pre-operative colonoscopy. ConclusionsAdherence to surveillance colonoscopy guidelines was low among our patients. Efforts should be directed toward patients at increased risk for non-adherence to surveillance colonoscopy guidelines.

Tu1151 QUALITY OF RECOMMENDATIONS AFTER SURVEILLANCE COLONOSCOPY IN OLDER ADULTS

Current guidelines for surveillance colonoscopy in adults age ≥75 recommend that decisions be individualized, which may lead to wide variation in practice patterns. We evaluated the content and clarity of endoscopist-written recommendations after surveillance colonoscopy in older adults. We performed a single center, retrospective, chart review of adults age ≥75 who underwent surveillance colonoscopy. We developed a data collection tool to facilitate data abstraction and minimize inter-observer variability. Kappa scores for recommendation assessments showed substantial agreement. Patient age and gender, endoscopist recommendations for follow-up, and follow-up letters after review of pathology were collected. Recommendations for follow-up were categorized based on content (continue vs. stop surveillance), definitiveness of the recommendation (definitive [e.g., “should,” “recommend”] vs. not definitive [e.g., “could,” “consider”]), and if/what rationale was provided (e.g. “because of your age…”). Differences in recommendations were evaluated using Fisher’s exact test at the 0.05 level of significance. Between 2012-2019, 4453 colonoscopies were performed in adults age ≥75, of which 1324 were for surveillance. We evaluated a subset of these (n=165) using stratified sampling to get a range of patient ages and findings for each endoscopist (n=11). 21.8% of reports contained no recommendation, ranging from 0% to 60.0% by endoscopist. There was a significant difference in the proportion of “stop” versus “continue” recommendation given across all endoscopists (p = 0.001) (Figure 1). There were no discrepancies between colonoscopy reports and post-pathology follow-up letters (Table 1). Among reports that included a recommendation, 69.0% were to continue surveillance, 69.0% were definitive, and 72.1% provided a rationale. There was no significant difference in the definitiveness of the recommendation based on stopping or continuing (p = 0.89). Exams that recommended stopping included a rationale 65.0% of the time, citing: age (57.5%), the current exam being normal (12.5%), overall health (7.5%), and the patient’s history of polyps (7.5%). Exams that recommended continuing included a rationale 76.4% of the time, citing the malignant potential of polyps (34.8%), the patient’s history of polyps (32.6%), and overall health (10.1%). There is considerable variation in the content and clarity of endoscopist recommendations after surveillance colonoscopy in older adults. Over a fifth lacked any recommendation. This study highlights opportunities for quality improvement targeted at standardizing endoscopist written post-colonoscopy recommendations. Next steps include understanding patient and referring provider interpretation of written recommendations and how variation in recommendations affects follow-up and clinical outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)