Extracting diagnostic stromal organization features based on intrinsic two-photon excited fluorescence and second-harmonic generation signals.

Intrinsic two-photon excited fluorescence (TPEF) and second-harmonic generation (SHG) signals are shown to differentiate between normal and neoplastic human esophageal stroma. It was found that TPEF and SHG signals from normal and neoplastic stroma exhibit different organization features, providing quantitative information about the biomorphology and biochemistry of tissue. By comparing normal with neoplastic stroma, there were significant differences in collagen-related changes, elastin-related changes, and alteration in proportions of matrix molecules, giving insight into the stromal changes associated with cancer progression and providing substantial potential to be applied in vivo to the clinical diagnosis of epithelial precancers and cancers.