Management of large polyps in a colorectal cancer screening program with fecal immunochemical test: a population-based study
Objective: To analyze presentation, management and outcomes of large (≥ 20 mm) polyps (LPs) detected in a colorectal cancer (CRC) screening program using a fecal immunochemical test (FIT). Design: Retrospective population-based study of all LPs detected in patients aged 50-74 years between 2015 and 2019 during FIT-positive colonoscopies within the screening program organized in Alsace (France). Results: Among 13,633 FIT-positive colonoscopies, 1256 LPs (8.5% malignant and 51.8% non-pedunculated) were detected by 102 community gastroenterologists in 1164 patients (one in 12 colonoscopies). The sensitivity of optical diagnosis of malignancy was 54% for non-pedunculated and 27% for pedunculated T1 CRCs. Endoscopic resection rate was 82.7% [95% CI 80.3-84.9] for benign LPs (70.2% [95% CI 66.4-74.1] non-pedunculated, 95.2% [95% CI 93.4-97.1] pedunculated, p<0.001), varying from 0 to 100% depending on the endoscopist. It was correlated with cecal intubation (Pearson r = 0.49, p<0.01) and adenoma detection (r = 0.25, p=0.01) rates. Most endoscopists did not refer patients to more experienced endoscopists, so that 60 to 90% of 183 surgeries for benign LPs were unwarranted. Endoscopic resection was curative for 4.3% [95% CI 0.9-12.0] of non-pedunculated and 37.8% [95% CI 22.5-55.2] of pedunculated T1 CRCs. Overall, 22 endoscopic submucosal dissections had to be performed to avoid one surgery. Conclusion: Compared with current recommendations, there is tremendous room for improvement of community endoscopy practices for the diagnosis and management of LPs. Detection and polypectomy competencies are correlated and highly variable among endoscopists. Endoscopic resection is curative in 83% of benign LPs and 16% of T1 CRCs.