Reevaluating the role of routine colonoscopy after acute diverticulitis: impact on colon cancer and advanced adenoma detection across age groups.

BACKGROUND

Colonoscopy is commonly performed after acute diverticulitis to exclude colorectal cancer (CRC) or advanced adenomas, but the true yield, especially in younger adults in the computed tomography era, remains uncertain. This study evaluated the diagnostic yield of follow-up colonoscopy with attention to age and timing.

METHODS

We conducted a retrospective cohort study within Allegheny Health Network from 2021 to 2024. Among 550 patients in an endoscopy-based dataset, 77 had documented acute diverticulitis and subsequently underwent lower endoscopic evaluation. Demographics, comorbidities, and colonoscopic outcomes were extracted from the electronic health record. Primary outcomes were detection of CRC and adenomas; advanced adenomas were identified only when explicitly noted. Secondary outcomes included colonoscopy timing and age-stratified yield.

RESULTS

Among 77 patients, CRC was detected in 4 (5.2%) and adenomas in 25 (32.5%). All neoplastic lesions occurred in adults aged ≥40 years, and all CRC cases were in patients aged ≥50 years. No lesions were found in patients aged 18 to 39 years. Only 31.7% underwent colonoscopy within 8 weeks, and delayed procedures did not appear to reduce yield.

CONCLUSIONS

Neoplastic findings after diverticulitis were confined to adults aged ≥40 years. No advantage was observed for colonoscopy strictly within 8 weeks, supporting selective, risk-based evaluation.