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.

Linked-color imaging versus white-light colonoscopy in an organized colorectal cancer screening program.

BACKGROUND AND AIMS: Linked-color imaging (LCI), a new image-enhancing technology emphasizing contrast in mucosal color, has been demonstrated to substantially reduce polyp miss rate as compared with standard white-light imaging (WLI) in tandem colonoscopy studies. Whether LCI increases adenoma detection rate (ADR) remains unclear. METHODS: Consecutive subjects undergoing screening colonoscopy after fecal immunochemical test (FIT) positivity were 1:1 randomized to undergo colonoscopy with LCI or WLI, both in high-definition systems. Insertion and withdrawal phases of each colonoscopy were carried out using the same assigned light. Experienced endoscopists from 7 Italian centers participated in the study. Randomization was stratified by gender, age, and screening round. The primary outcome measure was represented by ADR. RESULTS: Of 704 eligible subjects, 649 were included (48.9% men, mean age ± standard deviation, 60.8 ± 7.3 years) and randomized to LCI (n = 326) or WLI (n = 323) colonoscopy. The ADR was higher in the LCI group (51.8%) than in the WLI group (43.7%) (relative risk, 1.19; 95% confidence interval, 1.01-1.40). The proportions of patients with advanced adenomas and sessile serrated lesions were, respectively, 21.2% and 8.6% in the LCI arm and 18.9% and 5.9% in the WLI arm (not significant for both comparisons). At multivariate analysis, LCI was independently associated with ADR, along with male gender, increasing age, and adequate (Boston Bowel Preparation Scale score ≥6) bowel preparation. At per-polyp analysis, the mean ± standard deviation number of adenomas per colonoscopy was comparable in the LCI and WLI arms, whereas the corresponding figures for proximal adenomas was significantly higher in the LCI group (.72 ± 1.2 vs .55 ± 1.07, P = .05) CONCLUSIONS: In FIT-positive patients undergoing screening colonoscopy, the routine use of LCI significantly increased the ADR. (Clinical trial registration number: NCT03690297.).

Real-time gastric juice analysis with EndoFaster for H. pylori diagnosis: a large, multicentre study.

BACKGROUND: Helicobacter pylori infection is the main cause of the most frequent gastroduodenal diseases. Because its prevalence is decreasing in developed countries, gastric biopsies are negative in several patients. By measuring ammonium in the gastric juice, EndoFaster allows to exclude H. pylori infection during endoscopy. This study aimed to assess the accuracy of device versions working with either 6 ml or 3 ml of gastric juice. STUDY DESIGN: This prospective study involved 12 endoscopic units. During endoscopy, EndoFaster testing was performed and standard five gastric biopsies were taken. The accuracy was calculated by considering histological assessment as the gold standard for H. pylori diagnosis. RESULTS: Gastric juice analysis was attempted in 1279 patients, but it failed in 131 (15.5%) and in 10 (2.3%), with the 6 ml and the 3 ml device, respectively (P < 0.001). Overall, EndoFaster detected H. pylori infection with an 86.3% sensitivity, 83.3% specificity, 52.7% positive predictive value, 96.6% negative predictive value and 83.8% accuracy. The performance was not affected either by ongoing proton pump inhibitor therapy or a previous H. pylori eradication. No significant difference in accuracy emerged between the two versions of the device. CONCLUSION: The novel version of the EndoFaster device operating with 3 ml gastric juice may be performed in virtually all patients, and it allows excluding H. pylori infection with a very high accuracy. Gastric biopsies can be avoided in a definite portion of cases without endoscopic lesions or other clinical indications.

Real-time determination of gastric juice pH with EndoFaster® for atrophic gastritis assessment.

BACKGROUND: In patients with atrophic gastritis involving gastric body mucosa the pH value of gastric juice is distinctly increased, so that pH assessment would allow predict this precancerous lesion. We tested whether EndoFaster® - a device allowing real-time pH measure and H. pylori diagnosis - may optimize the need of taking gastric biopsies. METHODS: In this prospective, multicentre study, the accuracy of EndoFaster® for ruling out gastric atrophy involving corporal mucosa was assessed. Real-time pH and ammonium determination was performed by aspirating 3-6 ml gastric juice during endoscopy. Histology performed on 5 standard gastric biopsies was used as gold standard. RESULTS: A total of 1008 consecutive patients were observed in 12 centres. At histology, gastric body mucosa atrophy/metaplasia was detected in 65 (6.4%) cases, and a pH value >4.5 in the gastric juice was observed in 150 patients. The values of EndoFaster® performance in predicting the presence of atrophic gastritis were as follow: 51% sensitivity, 84% specificity, 18% PPV, 96% NPV, and 82% accuracy. The NPV value was not distinctly affected by neither ongoing proton pump inhibitor therapy nor H. pylori infection. By considering also data of ammonium concentrations, the values of EndoFaster® in detecting extensive atrophy on gastric mucosa were 74% sensitivity, 84% specificity, 24% PPV, 98% NPV, and 83% accuracy. CONCLUSION: The very high NPV of EndoFaster® might allow to safely rule out presence of atrophic gastritis, reducing the need of taking gastric biopsies in unselected patients managed in clinical practice.