Characterization of Computed Tomography Colonography Findings of Ulcerative Colitis-Associated Neoplasia.

BACKGROUND

Computed tomography colonography (CTC) is increasingly utilized for the evaluation of colorectal neoplasms. However, in patients with ulcerative colitis (UC), current European Crohn's and Colitis Organisation guidelines recommend CTC only for limited indications, such as the presence of strictures.

METHODS

This single-center, retrospective observational study included consecutive patients with UC who underwent preoperative CTC and were scheduled for pancolectomy for UCAN between January 2014 and June 2024. Lesion detectability on CTC was assessed in comparison with endoscopic findings, histopathological tumor depth, and morphological characteristics. Multivariable logistic regression was performed to identify factors associated with detectability on CTC.

RESULTS

Among 50 patients with 71 histologically confirmed lesions, 49% (35/71) were detectable by CTC. Detection was highest in advanced cancer (100%, 7/7), sessile (80%, 4/5) and depressed (80%, 8/10) morphologies, and lower in non-polypoid types such as superficial elevated (58%, 14/24) and flat (8%, 2/25) lesions. Detection by depth was 29% (12/42) for intramucosal, 75% (9/12) for submucosal, 100% (5/5) for muscularis propria, 73% (8/11) for subserosa/adventitia, and 100% (1/1) for serosal lesions. Flat morphology (adjusted odds ratio [aOR], 0.06; 95% confidence interval [CI], 0.01-0.27) and intramucosal invasion (aOR, 0.10; 95% CI, 0.02-0.46) were independently associated with non-detection.

CONCLUSIONS AND RELEVANCE: Despite preoperative awareness of UCAN, CTC demonstrated limited sensitivity. While CTC may serve a complementary role in selected cases, endoscopy remains essential for comprehensive lesion detection.