Factors of incomplete colonoscopy for stenosing colorectal cancer: CT colonography features

Purpose: The purpose of this study was to examine the relation between computed tomography colonoscopy (CTC) features of colorectal cancer (CRC) and incomplete colonoscopy. Materials and methods: The subjects of this retrospective study consisted of 108 patients with advanced CRC (57 men, 51 women; age range, 32–87 years; median, 65 years) who underwent CTC. We compared local CTC features between the groups of complete (n = 74) and incomplete colonoscopy (n = 34). We performed a receiver operating characteristic (ROC) analysis to assess a diagnostic performance of CTC features to predict incomplete colonoscopy. Results: The cross-sectional area of tumor and stenosis of complete colonoscopy group were significantly smaller and larger than those of incomplete colonoscopy group (p = 0.001 and < 0.001). Circumferential tumor extent rate (CER) showed significantly higher in the incomplete colonoscopy group than complete colonoscopy group (p < 0.001). In the ROC analysis, the cross-sectional area of stenosis showed AUC of 0.916, which was the best to predict incomplete colonoscopy. Conclusion: CTC features including larger cross-sectional area of tumor, smaller cross-sectional area of stenosis and 100% CER were significantly associated with incomplete colonoscopy for the patients with CRC.