Personal History Of Colorectal Cancer Research Articles

Serrated polyposis syndrome: defining the epidemiology and predicting the risk of dysplasia.

Serrated polyposis syndrome is the most common polyposis syndrome that has neoplastic potential. However, the natural history, genetic basis, and risk of dysplasia and neoplasia of serrated polyposis syndrome are incompletely understood. The objective of this study is to define the epidemiology of serrated polyposis syndrome. Using this data, we aim to evaluate candidate variables for predicting the risk of dysplasia and neoplasia in sessile serrated lesions found in serrated polyposis syndrome patients. Finally, we aim to use this data to create and evaluate clinical prediction models for accuracy in predicting dysplastic sessile serrated lesions in serrated polyposis syndrome patients. This was a regional Australian single-centre retrospective cohort study. Data was prospectively collected data from the clinical record database of a regional Australian gastroenterology practice. All patients undergoing colonoscopy at Port Macquarie Gastroenterology between January 2015 and September 2021 were screened for this study. Collected data included patient demographic, endoscopic, and histopathological findings. Clinical and endoscopic multivariate logistic regression models were created to predict dysplastic sessile serrated lesions. Model performance was examined using the area under the receiver operating curve. In total 8401 patients underwent a colonoscopy procedure during the study period. Serrated polyposis syndrome was diagnosed in 247, representing a prevalence of 2.94% (mean age 67.15 years, 62.75% female). Logistic regression identified; older age at serrated polyposis syndrome diagnosis, a personal history of colorectal cancer, size of the largest sessile serrated lesions removed, and total sessile serrated lesions count as predictors of dysplastic sessile serrated lesions. The clinical and endoscopic model had an area under the receiver operating curve of 0.75. Serrated polyposis syndrome is more common than previously described. The clinical and endoscopic variables identified in logistic regression have acceptable accuracy in predicting the risk of dysplasia, however other populations need to be studied to achieve generalisability and improve model performance.

The Diagnostic Yield of Genetic Testing in Patients With Multiple Colorectal Adenomas: A Specialist Center Cohort Study.

Adenoma multiplicity is associated with increased colorectal cancer (CRC) risk. The utility of genetic testing in patients with multiple colorectal adenomas (MCRA) remains uncertain. We evaluated the diagnostic yield of mutations in polyposis- and CRC-associated genes in patients with MCRA. We performed a cross-sectional review of adult patients with 10-99 cumulative adenomas from the prospective database at the St Mark's Hospital Polyposis Registry and Family Cancer Clinic between 1999 and 2021. Genetic testing was performed for adenomatous polyposis-associated genes, hamartomatous polyposis-associated genes, and nonpolyposis colorectal cancer-associated genes. Clinicopathological outcomes were extracted for multiple logistic regression analysis. Two hundred fifty-nine patients with MCRA (median age 61 [interquartile range 53-69] years) were identified. Sixty-six patients (25.5%) had a pathogenic variant or likely pathogenic variant, with APC and biallelic MUTYH mutations constituting the majority of identified pathogenic variant/likely pathogenic variants. Diagnostic yields were greater than 10% at any adenoma burden. In univariate analysis, higher adenoma burden and younger age were associated with higher yield (both P < 0.0001). In patients with MCRA with 10-19 adenomas without a relevant personal or family history of CRC, the diagnostic yield was nil. In multiple logistic regression analysis, higher adenoma burden, younger age, personal history of CRC, and first-degree familial history of CRC were associated with higher diagnostic yield. Diagnostic yield of >10% at any adenoma burden supports current guidance for constitutional genetic testing in patients with MCRA, although the low yield in people older than 60 years with 10-19 adenomas suggests that a stratified approach might be appropriate.

Colorectal cancer screening among the public: knowledge, attitudes, and the perceived barriers

ABSTRACT Colorectal cancer (CRC) 1 screening tests help in early detection of CRC and improve disease prognosis. This study aimed to assess knowledge, attitude, and barriers to CRC screening and the associated factors among the general population in Jordan. A validated self-administered online survey was distributed on 1542 individuals in Jordan. The participants (n = 1542) reported several barriers and demonstrated insufficient knowledge but positive attitude towards CRC screening. Older age (OR = 1.021, 95% CI = 1.010–1.032, P < 0.001), working in medical field (OR = 3.198, 95% CI = 2.499–4.092, P < 0.001), family history of cancer (OR = 1.248, 95% CI = 1.002–1.555, P < 0.05), and knowing someone with CRC (OR = 1.601, 95% CI = 1.186–2.161, P < 0.01) were significantly associated with higher knowledge. Personal history of CRC (OR = 3.157, 95% CI = 1.188–8.387, P < 0.05), and high knowledge of CRC (OR = 2.795, 95% CI = 2.242–3.484, P < 0.001) were significantly associated with the positive attitude. Future healthcare programs should devise effective techniques to improve public understanding and perception of CRC screening and overcome the identified barriers.

Colorectal cancer screening with fecal immunochemical testing: a community-based, cross-sectional study in average-risk individuals in Nigeria

The estimated incidence of colorectal cancer is rising in Nigeria, where most patients present with advanced disease. Earlier detection of colorectal cancer is a goal of the Nigerian National Cancer Control Plan, but the utility of fecal-based screening is unclear. This study aimed to assess the fecal immunochemical test as a colorectal cancer screening modality in average-risk individualS in Nigeria. A population-based, cross-sectional study of qualitative fecal immunochemical test-based colorectal cancer screening was done in asymptomatic, average-risk participants aged 45-75 years in three states in Nigeria (Osun, Kwara, and Lagos). Participants were invited to enrol using age-stratified and sex-stratified convenience sampling following community outreach. Exclusion criteria included a personal history of colorectal cancer or rectal bleeding in the previous 6 months, a first-degree relative with a known diagnosis of colorectal cancer, or a comorbidity that would preclude conscious sedation or general anesthesia. Participants with positive fecal immunochemical test results underwent colonoscopy, and the positive predictive value of fecal immunochemical testing for colorectal cancer and advanced adenomas (≥10 mm, tubulovillous or villous or high-grade dysplasia) was calculated. Data on demographics and acceptability of fecal immunochemical testing and colonoscopy were collected. Between January and April 2021, 2330 participants were enrolled in the study and received a fecal immunochemical test, which was returned by 2109 participants. 1677 participants tested negative and 432 tested positive. Of these 432 participants, 285 underwent a colonoscopy (235 showed no polyps or cancer, 47 had polyps identified, and three had colorectal cancer identified). Of the 47 participants who had polyps identified, 20 had advanced adenomas diagnosed. The median age was 57 years (IQR 50-63), 958 (41%) were male and 1372 (59%) were female, and 68% had at least a secondary-level education. Participants were evenly spread across wealth quintiles. The positivity rate of the fecal immunochemical test was 21% overall (432 of 2109; 95% CI 20-21%), 11% (51 of 455; 95% CI 10-12) in Lagos, 20% (215 of 1052; 95% CI 20-21) in Osun, and 28% (166 of 597; 95% CI 27-29) in Kwara. Among the patients with a positive fecal immunochemical test who completed colonoscopy, the positive predictive value for invasive colorectal cancer was 1·1% (95% CI 0·3-3·3), and 7·0% (4·5-10·8) for advanced adenoma. The acceptability of fecal immunochemical screening among participants was very high. Colorectal cancer screening with qualitative fecal immunochemical tests in Nigeria is feasible and acceptable to average-risk asymptomatic participants. However, the low positive predictive value for advanced neoplasia and high endoscopy burden investigating false positives suggests it might not be an appropriate screening tool in this setting. Thompson Family Foundation, Prevent Cancer Foundation, National Institutes of Health/National Cancer Institute Program Cancer Center.

S288 Missed High-Risk Adenomas and Colorectal Cancers Due to COVID-19 Pandemic at an Urban U.S. Tertiary Care Center in 2020

Introduction: During the COVID-19 pandemic, outpatient colonoscopies throughout the US were postponed, creating a significant backlog of procedures. We estimated the number of missed high-risk adenomas and colorectal cancers in 2020 at an urban, tertiary-care, safety-net teaching hospital in Boston, Massachusetts. Methods: This observational study evaluated the number of high-risk adenomas (defined as ≥3 adenomas, adenoma ≥10 mm in size, adenoma with tubulovillous or villous histological features, or adenoma with high-grade dysplasia) and colorectal cancers diagnosed by outpatient colonoscopy from January 2020 to November 2020, and compared it with those diagnosed from January 2017 to December 2019. Patients with a personal history of colorectal cancer or a colonoscopy indication of inflammatory bowel disease, therapeutic procedure (other than removal of large polyp), or diarrhea were excluded (10% of all colonoscopies). A Poisson regression model using colonoscopy data from 2017 to 2019--adjusted for age, sex, race/ethnicity and indication--was used to predict expected high-risk adenomas and colorectal cancers per month in 2020. Predicted values were compared to actual values to estimate missed diagnoses. Results: A total of 6597, 7136, and 6816 colonoscopies were performed in 2017, 2018 and 2019, respectively. There were 40% fewer colonoscopies performed in January to November 2020 (n = 3704) compared to the same period in 2019. In January to November 2020, 505 high-risk adenomas (Figure 1a) and 21 colorectal cancers (Figure 1b) were diagnosed. We estimate that 284 (36%) high-risk adenomas and 9 (30%) colorectal cancers were missed during this period. The rate of colorectal cancer detection was 6 per 1000 cases performed in 2017 to 2019. Assuming similar patient characteristics and indications, 1349 additional colonoscopies will be needed to diagnose 9 missed colorectal cancers. Conclusion: This study provides one of the first real world estimates of missed high-risk adenomas and colorectal cancers due to the cancellation of outpatient colonoscopies during the COVID-19 pandemic. The results have implications on planning strategies to schedule elective colonoscopies to increase the yield of detection of these high-risk lesions.Figure 1.: A. Actual versus Predicted High-Risk Adenomas. B. Actual versus Predicted Colorectal Cancers. Solid line—actual values; dashed line—predicted values; shaded area—95% confidence interval of predicted values.

The Performance of Colorectal Cancer Screening in Brazil: The First Two Years of the Implementation Program in Barretos Cancer Hospital.

Colorectal cancer is the second most common cancer in Brazil. Yet, a nationally organized colorectal screening program is not implemented. Barretos Cancer Hospital (BCH) is one of the largest Brazilian institution that cares for underserved patients. BCH developed a fecal immunochemical test (FIT)-based organized colorectal cancer screening program to improve colorectal cancer outcomes.This study aims to present the quality/performance measures of the first 2 years of the FIT-based colorectal cancer screening program and its impact on the colorectal cancer disease stage. Between 2015 and 2017, a total of 6,737 individuals attending the Outpatient Department of Prevention or the Mobile Unit of BCH, which visits 18 cities of Barretos county, ages 50 to 65 years, were personally invited by a health agent/nurse practitioner. Exclusion criteria were personal history of colorectal cancer, adenomatous polyps, inflammatory bowel disease, and colonoscopy, or flexible sigmoidoscopy performed in the past 5 years. European Union (EU) guidelines for colorectal cancer screening programs were evaluated. Overall, 92.8% returned the FIT, with an inadequate examination rate of 1.5%. Among the 6,253 adequately tested, 12.5% had a positive result. The colonoscopy compliance and completion rates were 84.6 and 98.2%, respectively. The PPVs were 60.0%, 16.5%, and 5.6% for adenoma, advanced adenoma, and cancer, respectively. Stage distribution of screen-detected cancers shows earlier stages than clinically diagnosed colorectal cancer cancers reported at BCH and Brazilian cancer registries. Our colorectal cancer screening program achieved desirable quality metrics, aligned with the EU guidelines. The observed shift toward earlier colorectal cancer stages suggests an exciting opportunity to improve colorectal cancer-related cancers in Brazil.

Colorectal Cancer Prevention in Lung Transplant Recipients: The Need for an Enhanced Surveillance Protocol

Solid organ transplant recipients are at increased risk for noncutaneous neoplasms, including colorectal cancer (CRC). We evaluated precancerous lesions detected by post-transplant surveillance colonoscopy to infer the rate at which new adenomas develop in this population. We reviewed all patients who underwent lung transplant between January 2013 and August 2017 at our institution. Those with post-transplant survival <1 year, personal history of CRC, previous lung transplant, and lack of pretransplant colonoscopy were excluded. During the study period, 411 patients underwent lung transplant; 237 met inclusion criteria. Median age at transplant was 63.6 (interquartile range [IQR] 59.2-68.3) years. Most recipients were immunosuppressed with a combination of prednisone, tacrolimus, and mycophenolate mofetil. At least 1 adenoma was found in 92 patients (38.8%) pretransplant and in 118 patients (49.8%) from 1 to 5 years post-transplant, with 68.6% identified at 1 year. Most adenomas were identified proximal to the splenic flexure. Multiple (≥3) adenomas were found in 31.4% of positive colonoscopies. Within 5 years after transplant, patients with a positive pretransplant colonoscopy had significantly more positive post-transplant colonoscopies than patients with a negative pretransplant colonoscopy (63.0% vs 41.4%, p < 0.001). No de novo CRC was identified. Lung transplant recipients have a significantly higher risk of adenoma formation than average-risk adults (25%-30% national detection rate). This increase occurs in the early post-transplant period (within 3 years). An enhanced CRC surveillance protocol for lung transplant recipients is needed.

The clinical and molecular characteristics of patients with personal history of colorectal cancer evaluated by cancer genetics counseling services.

46 Background: Genetic susceptibility to colorectal cancer (CRC) include well-defined hereditary syndromes such as Lynch Syndrome, Familial Adenomatous Polyposis syndrome (FAP), MUTYH-Associated Polyposis syndrome (MAP) and other less common syndromes. National Comprehensive Cancer Network (NCCN) guidelines recommend that individuals meeting certain criteria have detailed risk assessment and potential genetic testing. Here, we describe the clinical and molecular characteristics of patients with personal history of CRC evaluated by cancer genetics counseling services. Methods: This is an IRB-approved retrospective chart-review study. Between 2016 and 2020, 1011 unique genetic counseling visits were conducted. Germline testing was recommended by a certified genetic counselor if medically necessary. All patients with a personal history of CRC were identified (N = 52) and their clinical and molecular characteristics were summarized. Results: The median age is 50 years-old (29-82). Thirty-five (67%) patients were females. Caucasians, African Americans and other ethnic backgrounds represented 75%, 19% and 6% respectively. The primary tumor location was in the right colon, left colon and rectum in 29%, 37% and 27% of our cohort respectively. In 7%, the primary location of the tumor was not available. In our cohort, 11 out of 52 (21%) patients had a pathogenic germline mutation and 9 patients (17%) had a germline variant of unknown significance (VUS). Among patients with pathogenic germline mutations (N = 11), 4 patients had MSH2 mutations (MSH2 c.1759+1G &gt; A, MSH2 c. 1687dupT, MSH2 c.1861C &gt; T and MSH2 c.811_814delTCTG), 1 patient had a MSH6 mutation (MSH6 c.1012A &gt; T), 1 patient had a PMS2 mutation (PMS2 c.2182_2184delACTinsG), 3 patients had CHEK2 mutations (CHEK2 c.1100delC and CHEK2 c.470T &gt; C (p.I157T)), 2 patients had MUTYH mutations (MUTYH c.1187G &gt; A and MUTYH c.536A &gt; G) and 1 patient had a BRCA2 mutation (BRCA2 c.2808_2811delACAA). One patient had a CHEK2 and a MUTYH mutation. The VUS mutations in our cohort were POLE c.1645T &gt; C, POLE c.5480C &gt; T, c.2999G &gt; A, MLH1 c.1628A &gt; G, CTNNA1 c.503G &gt; A, MSH2 c.128A &gt; G, NBN c.16C &gt; T, ATM c.6537T &gt; G and AXIN2, BRCA1, NTHL1 mutations. Conclusions: In our cohort of patients with personal history of CRC, the majority of patients (62%) had negative germline testing. An underlying pathogenic germline mutation and VUS were identified in 21% and 17% of the patients respectively. Lynch Syndrome was the most commonly diagnosed hereditary CRC syndrome with 6 out of 11 patients found to have MMR germline mutations. Other pathogenic mutations were identified in the CHEK2, MUTYH and BRCA2 genes.

Participation in clinical trials increases the detection of pre-malignant lesions during colonoscopy.

colorectal adenoma detection has been associated with the effectiveness of cancer prevention. Clinical trials have been designed to determine the role of several interventions to increase the detection of pre-malignant lesions. We hypothesized that colonoscopy in the setting of clinical trials has a higher pre-malignant lesion detection rate. a cross-sectional study was performed that compared the detection of pre-malignant lesions in 147 randomly sampled non-research colonoscopies and 294 from the control group of two prospective trials. Outpatients aged 40-79 years, with no personal history of colorectal cancer (CRC) were included. baseline characteristics were similar between the two groups. The pre-malignant lesion detection rate in the trial vs control group was 65.6 % vs 44.2 % (OR 2.411; 95 % CI: 1.608-3.614; p < 0.001), the polyp detection rate was 73.8 % vs 59.9 % (OR 1.889; 95 % CI: 1.242-2.876; p = 0.003), the adenoma detection rate was 62.6 % vs 44.2 % (OR 2.110; 95 % CI: 1.411-3.155; p < 0.001) and the sessile serrated lesion detection rate was 17 % vs 4.1 % (OR 4.816; 95 % CI: 2.014-11.515; p < 0.001). The mean number of pre-malignant and sessile serrated lesions was 1.70 vs 1.06 (p = 0.002) and 0.32 vs 0.06 (p = 0.001) lesions per colonoscopy, respectively. There was no significant change in any of the study outcomes according to the multivariate analysis with each single potential confounder. patients involved in colonoscopy trials may benefit from higher quality examinations, as shown by the higher detection rates. Institutions should consider supporting clinical research in colonoscopy as a simple means to improve colonoscopy quality and colorectal cancer prevention.

Association between baseline hyperplastic polyps and metachronous serrated lesions

Some data suggest that individuals with numerous,<10-mm, rectosigmoid hyperplastic polyps (HPs) are at average risk for the development of metachronous advanced adenomatous neoplasia. Guidelines suggest that these individuals do not need surveillance colonoscopy and should be followed akin to individuals with a normal colonoscopy. Less is known of the risk of metachronous neoplasia because of≥1 HPs<10mm proximal to the sigmoid colon. We compared the risk of metachronous neoplasia between individuals with small HPs and those with normal colonoscopy, specifically addressing the impact of location and number of HPs on risk. Colonoscopy and pathology reports from patients with≥2 colonoscopies between 2004 and 2014 were reviewed. Exclusions included inpatients; age<40 or >75 years; and family or personal history of colorectal cancer, inflammatory bowel disease, previous colorectal surgery, or a previous colonoscopy with any adenoma, sessile serrated lesion (SSL), or HP≥10mm. The risk of metachronous neoplasia, including adenomas and SSLs, was compared in individuals with a normal index colonoscopy and those with<10-mm HPs stratified by location and number of HPs. After exclusion, 1795 patients were included. At index colonoscopy, 82% (n= 1469) had a normal examination, 12% (219) had only 1, and 6% (107) had between 2 and 9 HPs<10mm. Compared with patients with a normal index colonoscopy, patients with a proximal (odds ratio, 3.82; 95% confidence interval, 1.77-7.53) or distal HP (odds ratio, 2.23; 95% confidence interval, 1.18-4.00) had an increased risk of metachronous SSLs but not adenomas. Patients with small proximal and distal HPs are at increased risk of metachronous SSLs. These preliminary findings warrant consideration during surveillance recommendations and future studies in larger cohorts.

Family history of breast cancer in men with non-BRCA male breast cancer: implications for cancer risk counseling.

The role of genetic predisposition in male breast cancer (MBC) patients who test negative for a BRCA mutation is unclear. The aim of this study is to define the association between MBC and family history of breast cancer in patients without mutations in BRCA1 or BRCA2. We conducted an unmatched case-control study with men who received commercial testing for germline mutations in cancer susceptibility genes, including 3,647 MBC cases who tested negative for deleterious mutations in BRCA1/BRCA2, and 4,269 men with a personal history of colorectal cancer who tested negative for mutations in DNA mismatch repair genes to serve as controls. Associations between family history of breast cancer and MBC were estimated using unconditional multivariable logistic regression with adjustment for age, race/ethnicity and year of testing. Breast cancer in a first- or second-degree relative was associated with a four-fold increased odds of MBC (OR 4.7; 95% CI 4.1, 5.3). Associations with MBC were strongest for family history of breast cancer in 2 or more first-degree relatives (FDR) (OR 7.8; 95% CI 5.2, 11.6), for probands and FDR diagnosed at age < 45years (OR 6.9; 95% CI 3.9, 12.4), and for family history of MBC (OR 17.9; 95% CI 7.6, 42.1). Findings were confirmed in a sensitivity analysis of MBC cases who tested negative on a 25-gene pan-cancer panel. MBC patients without mutations in BRCA1/2 have significantly higher odds of a family history of breast cancer, suggesting the existence of unidentified MBC susceptibility alleles.

Characterizing germline APC and MUTYH variants in Ashkenazi Jews compared to other individuals.

Germline variants in the APC and MUTYH genes contribute to colorectal cancer (CRC) and adenoma risk, though may occur with varying frequencies in individuals of different ancestries. The aim of this study was to evaluate the prevalence of APC, monoallelic MUTYH and biallelic MUTYH germline variants in Ashkenazi Jewish (AJ) and Other Ancestry (OA) individuals with colorectal adenomas. We studied 7225 individuals with colorectal adenomas who had germline APC and MUTYH testing at a commercial laboratory. Cross-sectional medical history data were extracted from provider-completed test requisition forms. We performed bivariate analysis to compare the frequency of APC and MUTYH variants between AJ and OA, and examined APC p.I1307K and monoallelic MUTYH carrier phenotypes using logistic regression. Pathogenic APC variants occurred in 38/285 AJ (13%) and 1342/6940 OA (19%; P = 0.09); biallelic MUTYH variants in 2/285 (1%) AJ and 399/6940 (6%) OA (P < 0.0001); APC p.I1307K in 35/285 (12%) AJ and 29/6940 (1%) OA (P < 0.0001); and monoallelic MUTYH in 2/285 (1%) AJ and 133/6940 (2%) OA (P = 0.06). Monoallelic MUTYH variants were significantly associated with having a personal history of CRC, regardless of ancestry (OR 1.78; 95% CI 1.21-2.49; P < 0.01), but no significant association was found between APC p.I1307K variants and personal history of CRC (OR 1.38; 95% CI 0.79-2.44; P = 0.26). Ashkenazim with colorectal adenomas rarely have monoallelic or biallelic MUTYH variants, suggesting different genetic etiologies for polyposis in AJ compared to OA individuals. AJ ancestry assessment may be important in clinical evaluation for polyposis.

The impact of body weight on dysplasia of colonic adenomas: a case-control study

Objective: Colorectal cancer (CRC) is common across countries in males and females. Most cases originate from adenomas harboring high grade dysplasia. Among risk factors, weight excess has been suggested to positively influence dysplasia progression. In this study, the relationship between dysplasia grade of adenomas and body mass index (BMI) categories was analyzed.Methods: This was a retrospective case-control study. A total of 4745 charts (59.8% females) from patients undergoing colonoscopy were collected. Data regarding age, sex, smoking habits, occupation, residence, personal history of CRC, personal history of polyps and BMI were retrieved. Adenomas with high-grade dysplasia were labeled as advanced.Results: They were 970 (20.4%) subjects with adenomas (cases: mean age 64.67 ± 11.35 years) and 3775 without (controls: mean age 56.43 ± 16.56 years). As expected, adenomas were significantly associated with overweight or obesity. After adjusting for all covariates the presence of advanced adenoma was significantly associated with age, male sex, smoking habits, personal history of CRC, overweight (OR = 1.298, IC 95% 1.092–1.697) and obesity (OR = 1.780, IC 95% 1.260–2.515).Conclusions: Our findings support the protective effect a normal weight against advanced adenomas. Reduction of BMI value should be pursued in healthy programs.

2892 Adenoma Detection With Endocuff at a Veterans Affairs Medical Center: Encouraging Results From a Single Endoscopist Consecutive Series

INTRODUCTION: Improving adenoma detection rate should improve the colorectal cancer prevention that can be expected from screening and surveillance colonoscopies. METHODS: To address this goal, one endoscopist at the Albany Veterans Affairs Medical Center employed the Endocuff device (AEC120 or AEC130, Arc Medical, Leeds, UK), which attaches to the end of the colonoscope and has flexible projections that splay open the colonic lumen on withdrawal. Consecutive charts of all outpatients undergoing screening and surveillance colonoscopies were prospectively reviewed starting three months prior to institutional availability of the Endocuff and continued three months after. 91 cases were done with the Endocuff and 143 without. 21 cases were done without the Endocuff after institutional availability due to exhaustion of the supply, endoscopist failure to request the device, or fellow preference, and these are included in the analysis in the “without Endocuff” group. RESULTS: After excluding cases aborted for poor prep, 91 cases with and 135 cases without the Endocuff remained. The groups were not different with respect to sex, age, body mass index or hemoglobin A1c. Similar proportions of patients in each group had IBD, diverticulosis, family history of colorectal cancer, personal history of colorectal cancer or partial colectomy. The groups were also similar in quality of preparation, fellow participation, withdrawal time or sedative used for the procedure. Adenomas were detected in 47 of 91 (51.6%) patients in whom the Endocuff was used, with a total of 104 adenomas, vs. 61 of 135 (42.7%) patients in whom it was not, with a total of 143 adenomas. As the Endocuff provides a good view of the distal rectum on direct endoscopy, retroflexion in the rectum was not routinely performed with this device but was done without the device if there was suspicion for a distal rectal lesion. Even without retroflexed views, one rectal adenocarcinoma and one anal squamous cell carcinoma were detected in patients undergoing colonoscopy with the Endocuff. No cancers were detected in the patients in whom the Endocuff was not used but retroflexion in the rectum was performed. Results did not reach the P &lt; 0.05 level of significance with Pearson’s chi-squared test. CONCLUSION: High baseline rate of adenomas and small sample size were limitations of this study. These preliminary results show a trend toward increased adenoma detection with the Endocuff device in our patient population, and the trial is ongoing.

183 Epidemiology of Diverticulitis and Prevalence of First-Ever Colorectal Cancer Post-Diverticulitis in Adults in the United States Between 2014 and 2019: A Population-Based National Study

INTRODUCTION: Prior studies show the incidence of colorectal cancer (CRC) after an episode of diverticulitis ranges from 0 to 7.4%. We sought to describe the prevalence of first-ever diverticulitis in the US between 2014 and 2019 and evaluated the prevalence of first-ever CRC post diverticulitis in the US between January 2014 and 2019 utilizing a large population based database. METHODS: We queried a commercial database (Explorys Inc, OH), an aggregate of EHR data from 26 major integrated healthcare systems in the US from 1999 to 2019. We identified an aggregated patient cohort with a diagnosis of “diverticulitis of large intestine” from 2014 to 2019 followed by “first-ever primary malignant neoplasm of cecum, ascending colon, transverse colon, descending colon, sigmoid colon and/or rectum,” at least 1 day after and within 6 months of diverticulitis, aged &gt;18 years, based on Systemized Nomenclature of Medicine—Clinical Terms. We excluded patients with IBD, family and personal history of CRC. We calculated the prevalence of diverticulitis and CRC post diverticulitis overall and among different patient groups. RESULTS: Of the 31,441,890 individuals active in the database from 2014–2019, we identified 785,740 individuals with first-ever diverticulitis with an overall prevalence of 2.5%. The prevalence in male was 2.6%, females 2.4%, adults (age 18–65 years) 1.5%, senior (&gt;65 years) 5.5%, Caucasian 3.3%, African-American 2.3% and Asian 1.3% (Figure 1). Furthermore, 4,390 out of 785,740 individuals were diagnosed with CRC (first-ever) post diverticulitis with prevalence of 0.56% (Figure 2). In contrast, the prevalence of CRC without history of diverticulitis was 0.3%. Odds ratio (OR) of CRC post diverticulitis was 1.9 compared to individuals without diverticulitis (P &lt; 0.0001). The risk of CRC post diverticulitis was higher in female (OR 2.04, P &lt; 0.0001) vs male; African Americans (OR 2.16, P &lt; 0.0001) vs Caucasians and Asians; adults (OR 2.36, P &lt; 0.0001) than seniors (Figure 3). CONCLUSION: This is one of the largest population-based national studies that describes the epidemiology of diverticulitis and first-ever CRC post diverticulitis from 2014 to 2019. Prevalence of diverticulitis is higher in male, seniors, and Caucasians. Post diverticulitis, patients are twice as likely to be diagnosed with CRC. The risk of post diverticulitis CRC is higher in female, adults and African-Americans. Given the high burden of CRC, we advocate for screening for CRC after first occurrence of diverticulitis among adults.

Colorectal Cancer Prevention in Lung Transplant Recipients: The Need for an Enhanced Surveillance Protocol

BACKGROUND Solid organ transplant recipients are at increased risk for noncutaneous neoplasms, including colorectal cancer (CRC). We evaluated precancerous lesions detected by post-transplant surveillance colonoscopy to infer the rate at which new adenomas develop in this population. STUDY DESIGN We reviewed all patients who underwent lung transplant between January 2013 and August 2017 at our institution. Those with post-transplant survival <1 year, personal history of CRC, previous lung transplant, and lack of pretransplant colonoscopy were excluded. RESULTS During the study period, 411 patients underwent lung transplant; 237 met inclusion criteria. Median age at transplant was 63.6 (interquartile range [IQR] 59.2-68.3) years. Most recipients were immunosuppressed with a combination of prednisone, tacrolimus, and mycophenolate mofetil. At least 1 adenoma was found in 92 patients (38.8%) pretransplant and in 118 patients (49.8%) from 1 to 5 years post-transplant, with 68.6% identified at 1 year. Most adenomas were identified proximal to the splenic flexure. Multiple (≥3) adenomas were found in 31.4% of positive colonoscopies. Within 5 years after transplant, patients with a positive pretransplant colonoscopy had significantly more positive post-transplant colonoscopies than patients with a negative pretransplant colonoscopy (63.0% vs 41.4%, p < 0.001). No de novo CRC was identified. CONCLUSIONS Lung transplant recipients have a significantly higher risk of adenoma formation than average-risk adults (25%-30% national detection rate). This increase occurs in the early post-transplant period (within 3 years). An enhanced CRC surveillance protocol for lung transplant recipients is needed.

Clinical and Pathological Characterization of Lynch-Like Syndrome

Lynch syndrome is characterized by DNA mismatch repair (MMR) deficiency. Some patients with suspected Lynch syndrome have DNA MMR deficiencies but no detectable mutations in genes that encode MMR proteins-this is called Lynch-like syndrome (LLS). There is no consensus on management of patients with LLS. We collected data from a large series of patients with LLS to identify clinical and pathology features. We collected data from a nationwide-registry of patients with colorectal cancer (CRC) in Spain. We identified patients whose colorectal tumors had loss of MSH2, MSH6, PMS2, or MLH1 (based on immunohistochemistry), without the mutation encoding V600E in BRAF (detected by real-time PCR), and/or no methylation at MLH1 (determined by methylation-specific multiplex ligation-dependent probe amplification), and no pathogenic mutations in MMR genes, BRAF, or EPCAM (determined by DNA sequencing). These patients were considered to have LLS. We collected data on demographic, clinical, and pathology features and family history of neoplasms. The χ2 test was used to analyze the association between qualitative variables, followed by the Fisher exact test and the Student t test or the Mann-Whitney test for quantitative variables. We identified 160 patients with LLS; their mean age at diagnosis of CRC was 55 years and 66 patients were female (41%). The Amsterdam I and II criteria for Lynch syndrome were fulfilled by 11% of cases and the revised Bethesda guideline criteria by 65% of cases. Of the patients with LLS, 24% were identified in universal screening. There were no proportional differences in sex, indication for colonoscopy, immunohistochemistry, pathology findings, or personal history of CRC or other Lynch syndrome-related tumors between patients who met the Amsterdam and/or Bethesda criteria for Lynch syndrome and patients identified in universal screening for Lynch syndrome, without a family history of CRC. Patients with LLS have homogeneous clinical, demographic, and pathology characteristics, regardless of family history of CRC.

History of malignancy and relevant symptoms may predict a positive computed tomography enterography in obscure gastrointestinal bleeds.

This study aimed to assess the clinical utility of computed tomography enterography (CTE) and identify factors associated with a diagnostic CTE for patients with obscure gastrointestinal bleeding (OGIB). A retrospective observational study was performed at a Canadian tertiary care center from 2005 to 2015. A total of 138 patients underwent a CTE for OGIB. Univariate and multivariate logistic regressions were performed to determine factors associated with a diagnostic CTE. A highly sensitive clinical rule was then developed to help identify OGIB patients for whom a CTE may be beneficial in their clinical work-up. A possible bleeding source was identified in 30 (22%) cases. The presence of abdominal or constitutional symptoms as well as history of colorectal cancer was significantly associated with a positive CTE in univariate and multivariate analyses (P<0.05). A positive CTE could be predicted based on the presence of abdominal or constitutional symptoms and history of colorectal cancer with 90% sensitivity (95% CI 74-98%) in our population. CTE identified a possible source of OGIB in one in five cases. In patients with the presence of abdominal or constitutional symptoms and a personal history of colorectal cancer, CTE may contribute to their diagnostic work-up.

Surveillance colonoscopies frequently booked earlier than the National Health and Medical Research Council guidelines: findings of a single centre audit.

To assess the adherence rate of surveillance colonoscopy booking intervals to recommended National Health and Medical Research Council guidelines at The Queen Elizabeth Hospital, Adelaide, Australia. Patients on The Queen Elizabeth Hospital colorectal unit surveillance colonoscopy waiting list were included in this audit. Patient demographics, colonoscopy findings, follow-up plans and pathology results were analysed. Patients were categorized as normal/non-neoplastic finding, low-risk adenomas, high-risk adenomas, personal history of colorectal cancer (CRC) and family history of CRC. Booked colonoscopy within 2 months of guideline recommended interval was considered correct. A total of 467 patients were included (59.1% male; mean age 60 years). Two hundred and fifty-one (53.7%) patients had an incorrect surveillance colonoscopy booking. Twenty-seven patients with a normal/non-neoplastic previous colonoscopy not requiring surveillance colonoscopy were incorrectly booked for a colonoscopy. For the 222 patients booked incorrectly and requiring surveillance colonoscopy, 88.7% were early and 11.3% were late. The proportions of incorrect bookings were highest in the low-risk finding (66.1%) and history of CRC (67.6%) groups. For the 186 patients requiring a 3-year surveillance interval, 38.7% were booked incorrectly. For the 197 patients requiring a 5-year surveillance interval, 63.5% were booked incorrectly, of which 99.2% were early. More 5-year surveillance interval patients were booked at 3 years (n = 79), than at the correct interval of 5 years (n = 72). Adherence to the National Health and Medical Research Council guidelines for surveillance colonoscopy is poor. The majority of deviations represent early follow-up, which is most common among patients with low-risk findings or history of CRC. There is a tendency towards 3-year surveillance among low-risk patients.

Identifying Predictors of Repeat Colon Cancer Screening Following an Incomplete Colonoscopy

Introduction: For a complete colonoscopy, a number of factors such as adequate prep and patient tolerance are involved in order to identify precursor lesions and potentially remove them. We reviewed patients who underwent incomplete colonoscopies with the purpose of identifying those who are at risk of incomplete colonoscopy and to predict those who undergo subsequent exams. Methods: This is an observational, retrospective, single-institution study of patients who underwent an incomplete colonoscopy, from 2005-2013, as determined by Current Procedural Terminology (CPT) coding. The following characteristics were reviewed: patient demographics, past medical and family history, colonoscopy findings, follow up exams, pathology, cancer staging, and mortality. Logistic regression analysis was used to identify predictors of repeat exams. Results: In our study, 902 incomplete colonoscopy exams were reviewed. Six patients were not of African American (AA) or White race/ethnicity and were excluded. Of the remaining 896 patients, 588 (66%; median age =59 yo, 30% male, 39% AA) underwent a subsequent complete exam of the colon, most within 1 year (85%). Patient characteristics include a history of abdominal surgery (62%), narcotic use (11%), and prior incomplete colonoscopy (7.7%). Twelve percent had a family history of colorectal cancer (CRC) and 6% had a personal history of CRC. The most common reasons for incomplete colonoscopy were inadequate prep (48%) and inability to pass the scope (53%). Ten percent of initial exams reached the cecum while 46% were limited to the sigmoid. Eighty-three patients (14%) had lesions identified on incomplete colonoscopy, of which 26 had advanced histology. Barium enema comprised the majority of subsequent exams (45%) followed by repeat colonoscopy (38%) and CT colonography (7%). On stepwise regression modeling, incomplete visualization was the highest predictor of repeat exam with sigmoid visualization being the most significant (OR 4.12 95% CI 2.56,6.67). In addition, lesions visualized (OR 1.84 95% CI 1.16,2.91), patients with IBD (OR 1.69 CI 0.82,3.48), and the inability to pass the scope (OR 1.40 95% CI1.02,1.94) were predictive of patients undergoing repeat exam. Conclusion: There are a number of potential characteristics that identify patients who are more likely to repeat colon cancer screening. With further prospective studies, we can better identify those patients who do not return for colon cancer screening and identify measures to improve screening outcomes.2756 Figure 1. Full Logistic Regression Model Examining Independent Predictors of Repeat Colorectal Cancer Screening After Incomplete Colonoscopy