Low Colorectal Cancer Risk After Resection of High-Risk Pedunculated Polyps.

BACKGROUND: Post-fecal immunochemical test (FIT) colonoscopy represents a setting with an enriched prevalence of advanced adenomas. Due to an expected higher risk of colorectal cancer (CRC), postpolypectomy surveillance is recommended, generating a substantially increased load on endoscopy services. The aim of our study was to investigate postpolypectomy CRC risk in a screening population of FIT+ subjects after resection of low-risk adenomas (LRAs) or high-risk adenomas (HRAs). METHODS: We retrieved data from a cohort of patients undergoing postpolypectomy surveillance within a FIT-based CRC screening program in Italy between 2002 and 2017 and followed-up to December 2021. Main outcomes were postpolypectomy CRC incidence and mortality risks according to type of adenoma (LRA/HRA) removed at colonoscopy as well as morphology, size, dysplasia, and location of the index lesion. We adopted as comparators FIT+/colonoscopy-negative and FIT- patients. The absolute risk was calculated as the number of incident CRCs per 100,000 person-years of follow-up. We used Cox multivariable regression models to identify associations between CRC risks and patient- and polyp-related variables. RESULTS: Overall, we included 87,248 post-FIT+ colonoscopies (133 endoscopists). Of these, 42,899 (49.2%) were negative, 21,650 (24.8%) had an LRA, and 22,709 (26.0%) an HRA. After a median follow-up of 7.25 years, a total of 635 CRCs were observed. For patients with LRAs, CRC incidence (hazard ratio [HR], 1.18; 95% confidence interval [CI], 0.92-1.53) was not increased compared with the FIT+/colonoscopy-negative group, while for HRAs a significant increase in CRC incidence (HR, 1.53; 95% CI, 1.14-2.04) was found. The presence of 1 or more risk factors among proximal location, nonpedunculated morphology, and high-grade dysplasia explained most of this excess CRC risk in the HRA group (HR, 1.85; 95% CI, 1.36-2.52). Patients with only distal pedunculated polyps without high-grade dysplasia, representing 39.2% of HRA, did not have increased risk compared with the FIT- group (HR, 0.87; 95% CI, 0.59-1.28). CONCLUSIONS: CRC incidence is significantly higher in patients with HRAs diagnosed at colonoscopy. However, such excess risk does not appear to apply to patients with only distal pedunculated polyps without high-grade dysplasia, an observation that could potentially reduce the burden of surveillance in FIT programs.

Adenoma Detection Rate and Colorectal Cancer Risk in Fecal Immunochemical Test Screening Programs : An Observational Cohort Study.

BACKGROUND: Colorectal cancer (CRC) screening programs based on fecal immunochemical tests (FITs) represent the standard of care for population-based interventions. Their benefit depends on the identification of neoplasia at colonoscopy after FIT positivity. Colonoscopy quality measured by adenoma detection rate (ADR) may affect screening program effectiveness. OBJECTIVE: To examine the association between ADR and postcolonoscopy CRC (PCCRC) risk in a FIT-based screening program. DESIGN: Retrospective population-based cohort study. SETTING: Fecal immunochemical test-based CRC screening program between 2003 and 2021 in northeastern Italy. PATIENTS: All patients with a positive FIT result who had a colonoscopy were included. MEASUREMENTS: The regional cancer registry supplied information on any PCCRC diagnosed between 6 months and 10 years after colonoscopy. Endoscopists' ADR was categorized into 5 groups (20% to 39.9%, 40% to 44.9%, 45% to 49.9%, 50% to 54.9%, and 55% to 70%). To examine the association of ADR with PCCRC incidence risk, Cox regression models were fitted to estimate hazard ratios (HRs) and 95% CIs. RESULTS: Of the 110 109 initial colonoscopies, 49 626 colonoscopies done by 113 endoscopists between 2012 and 2017 were included. After 328 778 person-years follow-up, 277 cases of PCCRC were diagnosed. Mean ADR was 48.3% (range, 23% and 70%). Incidence rates of PCCRC from lowest to highest ADR group were 13.13, 10.61, 7.60, 6.01, and 5.78 per 10 000 person-years. There was a significant inverse association between ADR and PCCRC incidence risk, with a 2.35-fold risk increase (95% CI, 1.63 to 3.38) in the lowest group compared with the highest. The adjusted HR for PCCRC associated with 1% increase in ADR was 0.96 (CI, 0.95 to 0.98). LIMITATION: Adenoma detection rate is partly determined by FIT positivity cutoff; exact values may vary in different settings. CONCLUSION: In a FIT-based screening program, ADR is inversely associated with PCCRC incidence risk, mandating appropriate colonoscopy quality monitoring in this setting. Increasing endoscopists' ADR may significantly reduce PCCRC risk. PRIMARY FUNDING SOURCE: None.

Colonoscopic findings in first-degree relatives of patients with colorectal cancer: a population-based screening program.

BACKGROUND: A screening colonoscopy is recommended in first-degree relatives (FDRs) of colorectal cancer patients; few prospective, controlled studies have evaluated colorectal findings in a population-based screening program. OBJECTIVE: To evaluate the prevalence of colorectal neoplasia (adenomas and adenocarcinomas) in this increased-risk population, to compare it with that of average-risk individuals, and to identify features that might allow risk stratification for neoplasia among FDRs. DESIGN: Cross-sectional study. SETTING: Population-based screening program in Trentino, Italy. PATIENTS: FDRs of colorectal cancer patients between 45 and 75 years of age with no history of hereditary colorectal cancer syndromes or inflammatory bowel disease. CONTROLS: Average-risk individuals undergoing screening colonoscopy. INTERVENTION: Screening colonoscopy. RESULTS: Neoplasia was found in 33.4% of 1252 FDRs and in 30.3% of 765 controls; advanced neoplasia was found in 11.3% of FDRs and in 6.3% of controls. Odds ratios (ORs) from the multivariate logistic regression analysis adjusted for age, sex, cecal intubation rates, and colon cleansing showed an increased risk of advanced neoplasia (OR 2.41; 95% CI, 1.69-3.43; P < .0001) in FDRs. Age older than 56 years (OR 1.83; 95% CI, 1.15-2.99; P = .013) and male sex (OR 2.17; 95% CI, 1.39-3.10; P < .001) are independent predictors of advanced neoplasia. LIMITATIONS: Italian subjects living in the same geographic area; of 4301 FDRs, 2521 were excluded. CONCLUSIONS: The increased risk of advanced neoplasia supports the current recommendation for colonoscopic screening in this group; age and sex may assist in risk stratification of these individuals.

Appropriateness and yield of surveillance colonoscopy in first-degree relatives of colorectal cancer patients: A 5-year follow-up population-based study.

BACKGROUND AND AIMS: There are few prospective data about the use of surveillance colonoscopy and the risk of recurrent neoplasia in first degree relatives (FDRs) of colorectal cancer (CRC) patients. We examined the use and yield of surveillance colonoscopy in a population-based screening program (Trentino, Italy) METHODS: 1252 FDRs have been included in this study. We calculated compliance (percentage of FDRs who underwent surveillance colonoscopy among those eligible), appropriateness of colonoscopy (appropriate if performed within 6 months of the guidelines recommended interval) and diagnostic yield for neoplasia. We compared these data with those of 765 individuals without a family history (FH) of CRC who underwent screening colonoscopy in the same period (controls). RESULTS: Compliance and appropriateness were higher in FDRs than in controls (93.0% vs. 48.0%; p < 0.001; 59.6% vs. 18.8%; p < 0.0001, respectively). Younger age, female sex, FH of CRC and both non-advanced adenomas (nAA) and advanced adenomas (AA) at screening colonoscopy were predictors of appropriate surveillance. The cumulative incidence of nAA and AA was similar in FDRs and controls (31.7% and 4.9% in FDRs, including three invasive cancers; 32.4% and 5.8% in controls, respectively). CONCLUSION: FH does not increase the risk of AA in a 5-year follow-up; appropriate surveillance practices in FDRs could be highly expected in an organized screening program.