Evaluating Chemopreventive and Chemotherapeutic Agent Effectiveness in a Mouse Model of Sporadic Colorectal Cancer Using Optical Coherence Tomography

Abstract

Optical coherence tomography (OCT) is a minimally-invasive imaging modality that generates high resolution cross-sectional images of tissue. The present study employed a 2 mm diameter endoscopic spectral domain OCT system in the in vivo evaluation of the drugs α-Difluoromethylornithine and Sulindac as chemopreventive and chemotherapeutic agents in a mouse model of sporadic colorectal cancer. 30 mm lateral images of each colon at eight different rotations were obtained at five different time points. Visual analysis of the images was performed to determine the number and size of discrete adenomas, with gross photos and histology serving as gold standard confirmation of the final imaging time point. When applied for chemoprevention, DFMO and Sulindac both significantly reduced the incidence of adenoma, appearing to interact additively in the prevention of tumorigenesis. For chemotherapy, however, only Sulindac had a significant effect on the number of adenoma and neither DFMO nor Sulindac significantly affected tumor growth.