Spectroscopic fluorescence characteristics of DMBA-induced hamster buccal pouch carcinogenesis

For the early detection of oral neoplasia, light-induced fluorescence spectroscopy has been used to measure the fluorescence emission of malignant human oral tissues as well as normal oral mucosal tissues. Significant differences of emission spectra between histological normal and neoplastic human oral tissues were obtained under the excitation wavelengths of 330 nm. In this study, an animal model of 7,12-dimethylbenz[a]anthracene (DMBA)-induced squamous cell carcinogenesis in the hamster buccal pouch was used to elucidate whether the observed alternations of fluorescence spectroscopy were correlated with the progressive development of squamous cell carcinoma. Correlated with the spectra profile of human oral mucosal tissues, the most intensely fluorescent peak occurred at 380-nm and 460±10 nm emission for these different stages of tissues under the 330-nm excitation. At 380-nm emission, the intensity of the normal tissue was significantly stronger than that of the different stages of abnormal tissues. However, at 460-nm emission, the intensity of the normal hamster buccal mucosal tissues was not only significantly weaker but also shifted to 470-nm, compared to those of the different stages of carcinoma tissues. These results suggest that, under the 330-nm excitation wavelength, light-induced fluorescence spectroscopy may be useful for the early detection of oral neoplastic lesions.