NATIVE CELLULAR FLUORESCENCE CAN IDENTIFY CHANGES IN EPITHELIAL THICKNESS IN-VIVO IN THE UPPER AERODIGESTIVE TRACT

BACKGROUND: Change in epithelial thickness is part of the neoplastic t ransformation process of the upper aerodigestive tract. The quantitati on of native cellular fluorescence (NCF) may represent a noninvasive m eans of distinguishing such a change. PATIENTS AND METHODS: Nineteen p atients with squamous neoplasms and 12 surgical specimens from cancer patients were analyzed for NCF using a hand-held fiber optic probe att ached to a fluorescent spectrometer. Tumors and normal sites were anal yzed for fluorescence, and tissue samples were obtained. Ratios of int ensities of various emitted wavelengths were computed to quantitate an d compare various spectral patterns, These ratios were then correlated with mucosal thickness. RESULTS: The 330 nm peak in the excitation sc an (lambda Ex 200 to 360 nm, lambda Em 380 nm) was lost in the tumors compared with the normal sites. The 390 nm peak in the emission scan ( lambda Ex 340 nm, lambda Em 360 to 660 nm) was also lost, The 290 nm/3 30 nm ratio in the in-vivo excitation scan (lambda Ex 200 to 360 nm, l ambda Em 380 nm) correlated with changes in epithelial thickness, The 390/450 ratio in the emission scan (lambda Ex 340 nm, lambda Em 360 to 660 nm) correlated negatively with the mean epithelial thickness. CON CLUSIONS: Native cellular fluorescence analysis can identify changes i n neoplastic tissues, including changes in epithelial thickness.