RESUMEN
BACKGROUND : Current guidelines recommend genetic counseling and intensive colonoscopy surveillance for patients with ≥â10 colorectal adenomas based on scarce data. We investigated the prevalence of this condition in a fecal immunochemical test (FIT)-based colorectal (CRC) screening program, and the incidence of metachronous lesions during follow-up. METHODS: We retrospectively included all FIT-positive participants with ≥â10 adenomas at index colonoscopy between 2010 and 2018. Surveillance colonoscopies were collected until 2019. Patients with inherited syndromes, serrated polyposis syndrome, total colectomy, or lacking surveillance data were excluded. The cumulative incidence of CRC and advanced neoplasia were analyzed by Kaplan-Meier analysis. Risk factors for metachronous advanced neoplasia were investigated by multivariable logistic regression analysis. RESULTS: 215 of 9582 participants (2.2â%) had ≥â10 adenomas. Germline genetic testing was performed in 92â% of patients with ≥â20 adenomas, identifying two inherited syndromes (3.3â%). The 3-year cumulative incidence of CRC and advanced neoplasia were 1â% and 16â%, respectively. In 39 patients (24.2â%), no polyps were found on first surveillance colonoscopy. The presence of an advanced adenoma was independently associated with a higher risk of advanced neoplasia at first surveillance colonoscopy (odds ratio 3.91, 95â%CI 1.12-13.62; Pâ=â0.03). Beyond the first surveillance colonoscopy, the risk of metachronous advanced neoplasia was lower. CONCLUSIONS: The prevalence of ≥â10 adenomas in a FIT-based CRC screening program was 2.2â%; a small proportion of inherited syndromes were detected, even amongst those with ≥â20 adenomas. A low rate of post-colonoscopy CRC was observed and the risk of advanced neoplasia beyond the first surveillance colonoscopy tended to progressively decrease throughout successive follow-ups.