Multiphoton morpho-functional imaging of healthy colon mucosa, adenomatous polyp and adenocarcinoma

Two-photon spectral resolved imaging was used to image fresh human biopsies of colon tissue and to characterize healthy colon mucosa, adenomatous polyp and adenocarcinoma by means of a morpho-functional analysis. Morphological examination, performed using endogenous tissue fluorescence, discriminated adenomatous and adenocarcinoma tissues from normal mucosa in terms of cellular asymmetry and nucleus-to-cytoplasm ratio. Good agreement was found between multiphoton images and histological examination performed on the same samples. Further characterization, performed by means of spectral-resolved analysis of NADH and FAD fluorescence, demonstrated an altered metabolic activity in both adenomatous and adenocarcinoma tissues compared to healthy mucosa. This morpho-functional approach may represent a powerful method to be used in combination with endoscopy for in vivo optical diagnosis of colon cancer and may be extended to other tissues.