Endogenous and exogenous fluorescence spectroscopy of gastrointestinal tumours - in vitro studies

摘要

We present fluorescence data obtained from normal and cancerous gastrointestinal tissues - oesophageal and colon lesions, taken up to two hours after surgical removal with and without exogenous fluorescent markers applied. The major goal was to acquire information on the differences between the fluorescent spectra of normal and pathological tissues. Excitation-emission matrices in a broad spectral range (excitation from 280 to 450 nm, a step of 10 nm, and emission from 300 to 700 nm, a step of 1 nm) were detected and the major endogenous fluorophores for the normal and the diseased tissues were identified. The fluorescence signals detected during endoscopic observations can be used for initial diagnosis of gastrointestinal tract (GIT) cancer, as well as for fluorescent monitoring and mapping during open surgical procedures for removal of lower gastrointestinal tract tumours. The endogenous and exogenous fluorescent data were compared using the 5-ALA-mediated PplX fluorophore as a contrast agent in view of evaluating the diagnostic applicability of these two fluorescent spectroscopic modalities and their feasibility for common clinical applications alone and in a combination.