Site-specific Performance of ColonView (CV) Fecal Immunochemical Test (FIT) With Differences Between Proximal and Distal Colorectal Adenoma

Abstract

Background/aim: The aim of this study was to assess the diagnostic accuracy (DA) of a ColonView (CV) test in proximal versus distal colorectal adenoma (pCRA versus dCRA).

Patients and methods: The colorectal neoplasia (CRN) screening cohort included 5,090 individuals and 506/5,090 (10%) were eligible for the study. Finally, only 127/506 were included in the CRA analysis and hierarchical summary ROC (HSROC) curves were used to show the pooled overall DA of visually analyzed (VA) and automatically analyzed (AA) techniques in pCRA and dCRA detection.

Results: The overall specificity (Sp) of the AA technique for the pCRA and dCRA endpoint was 46% and 43%, respectively. The most sensitive AA test in pCRA patients showed 76% sensitivity (Se) versus 58% Se in dCRA patients. In the HSROC analysis, area under the curve (AUC) values were as follows: i) VA in pCRA: AUC=0.503, ii) AA in pCRA: AUC=0.560, iii) VA in dCRA: AUC=0.552 and iv) AA in dCRA: AUC=0.486. In Roccomp analysis, the statistically significant AUC values were available between VA and AA reading modes in pCRA (p=0.044) and in AA reading between pCRA and dCRA (p=0.024).

Conclusion: As compared with the CRC endpoint, the DA value of the CV test is far inferior for the CRA endpoint, as determined by the AUC values.

Keywords: FIT; Fecal occult blood; HSROC; ROC; colorectal adenoma screening; false negative; false positive; fecal immunochemical test; sensitivity; specificity.