AUTOFLUORESCENCE SPECTRA OF A SPECIMEN OF NON-KERATINIZING LARYNGEAL SQUAMOUS CELL CARCINOMA IN ACCORDANCE WITH A HISTOLOGICAL STUDY

Abstract

Abstract. The prevalence of oncological diseases of ear, nose and throat organs tends to increase in recent years. This paper describes a method for the early diagnosis of diseases of the pharynx and larynx, accompanied by epithelial dysplasia using autofluorescence spectroscopy. Fluorescence spectroscopy is a non-invasive, highly sensitive, versatile and relatively easy-to-use method that allows combined diagnostics and the ability to work in real time without tissue trauma. Its use in the diagnosis of various diseases is due to the fact that during the development of pathologies, biochemical changes occur in the tissue, and, consequently, the relative content of the main fluorophores and chromophores changes, the morphological and histological parameters of the tissue change and, as a result, their contribution to the overall observed fluorescence spectrum fabrics. Fluorescence was started using an LGI-505 nitrogen laser (excitation wavelength 337 nm, pulse repetition rate up to 1 kHz, pulse duration 6–10 ns). Registration of autofluorescence spectra carried out by usage a spectrum analyzer with fiber optic input LESA-7med. For the study, we used a sapecimen of the larynx obtained during laryngectomy wich previously histologically confirmed as laryngeal cancer. Biopsy performed in limited areas of the mucosa determined by the autofluorescence spectra analysis. Then a standard histological examination of biopsy samples were performed. A direct correlation was found between the results of autofluorescence spectroscopy and histological examination of identical localization areas of the object under study. Thus, squamous cell carcinoma is characterized, along with a general decrease in fluorescence intensity, by the shift of the main maximum of the spectrum in the region of 435-455 nm. The low content of NADH in tumor cells, as well as dysproteinemia developing in malignant diseases, are the main reason for the decrease in the intensity of the autofluorescence spectrum.