Combination of colonoscopy quality control indicators and CT imaging features for evaluation of diagnostic performance for colorectal lesions

This study was designed to assess the diagnostic performance of integrating colonoscopy quality metrics with computed tomography (CT) imaging characteristics for the detection of colorectal lesions. A retrospective analysis was performed on clinical data from 15,828 participants who had undergone colonoscopy during the period from January to December 2024. With histopathological results utilized as the reference standard, the diagnostic sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of colonoscopy, whole-abdominal contrast-enhanced CT, and the combined colonoscopy-CT approach were compared for the identification of adenomas, polyps, early-stage colorectal carcinoma, and advanced colorectal carcinoma. Logistic regression modeling was applied to assess the diagnostic performance of the three modalities. The quality control indicators used were the adenoma detection rate (ADR), polyp detection rate (PDR), and cecal intubation rate (CIR), and these were integrated with CT imaging features as part of the combined diagnostic approach. Colonoscopy significantly outperformed CT in detecting lesions across all categories and in diagnostic efficacy ( P < 0.05). Combined screening further enhanced sensitivity, specificity, and accuracy, significantly surpassing either modality alone ( P < 0.05). Colonoscopy significantly detected more serrated adenomas and high-risk adenomas than CT alone, while the combined use of both methods further increased detection rates. Colonoscopy was found to exhibit significantly higher sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value than CT for the detection of serrated adenomas and high-risk adenomas ( P < 0.05). The combined diagnostic approach was demonstrated to significantly outperform each modality across all evaluated metrics ( P < 0.05). Logistic regression modeling revealed that the integrated CT and colonoscopy strategy exhibited the most favorable diagnostic performance for identifying colorectal carcinoma, followed by colonoscopy alone. CT combined with colonoscopy significantly outperformed standalone CT and colonoscopy in detecting various colorectal lesions, particularly serrated adenomas and high-risk adenomas, as well as in overall diagnostic efficacy. Multimodal combined assessment is recommended for high-risk populations or suspected cases in clinical practice to achieve earlier, more accurate, and comprehensive diagnosis, providing a solid foundation for individualized treatment and precise staging.