Endoscopic optical coherence tomography and laser-induced fluorescence spectroscopy in a murine colon cancer model

Background and Objectives: The diagnostic feasibility of optical coherence tomography (OCT) and laser-induced fluorescence (LIF) have been evaluated for human colorectal cancer. This study applies these technologies to a murine model of colorectal adenoma. Study Design/Materials and Methods: The lower colon of 10 Apc^Min and two C57BL/6J mice was surveyed over five 4-week intervals using a prototype 2.0 mm diameter OCT-LIF endoscope-based system. Four categories were histologically classified: control C57BL/6J, adenomatous, non-diseased regions of adenomatous, and non-diseased Apc^Min. OCT images were compared to histology. Spectra from the four categories were compared via the Student's t-test. Results: Three Apc^Min and two control mice completed the study. One adenoma was histologically identified; OCT visualized mucosal thickening/abnormal mass development over the imaging timepoints. LIF spectral comparisons revealed decreased 405 nm intensity and the presence of a peak at 680 nm in the adenomatous Apc^Min. Conclusions: These preliminary data indicate endoscopic OCT-LIF has the potential to identify colorectal adenomas in murine models.