Optical coherence tomography for the early detection of colorectal dysplasia and cancer: validation in a murine model.

Background: There is an urgent need to develop a non-invasive imaging technique for detecting colorectal dysplasia and cancer. Technology for early and real-time microscopic assessments to select the most representative biopsy sites would also be of clinical value. In this study, we explored the sensitivity of optical coherence tomography (OCT) in detecting local lesions to demonstrate its potential for the early detection of colorectal dysplasia and cancer.

Methods: An azoxymethane/dextran sodium sulfate mouse model of colorectal carcinogenesis was utilized. Mice were imaged by OCT, and colorectal tissue sections were observed with hematoxylin and eosin staining. The results of the parallel analyses were compared to evaluate the performance of OCT in imaging and early screening of colorectal lesions.

Results: Dysplasia and cancer could be distinguished from normal colon tissues based on the OCT images. However, simple morphological changes observed in the OCT images were not sufficient to distinguish different degrees of dysplasia or distinguish dysplasia from cancerous tissues. The Youden index and diagnostic efficiency of OCT for colorectal dysplasia and cancer were 62.50% and 82.14%, respectively, while the sensitivity and specificity were 87.50% and 75.00%, respectively. Further, the positive and negative predictive values were 82.35% and 81.82%, respectively.

Conclusions: Based on our findings, we predict that OCT is a promising non-invasive imaging technique that can offer excellent positive detection rates and diagnostic accuracy for early colorectal dysplasia and cancer. This technique is expected to be valuable in realizing real-time qualitative analysis and guided targeted biopsy.