IN-VIVO NATIVE CELLULAR FLUORESCENCE AND HISTOLOGICAL CHARACTERISTICSOF HEAD AND NECK-CANCER

Native cellular fluorescence (NCF) represents the innate capacity of t issues to absorb and emit light of a specified wavelength. The ability to define the relationship of ill vivo NCF with biological characteri stics of neoplastic disease may allow for an improved understanding of the clinical course of disease. Head and neck cancers from 35 patient s were evaluated in vivo for NCF characteristics using a xenon lamp-ba sed spectrometer coupled to a handheld fiberoptic probe. Spectral asse ssment was limited to lambda 450-nm emission characteristics, in which tissues were excited at various wavelengths, ranging from lambda 290 nm to lambda 415 nm, and the intensity of lambda 450 nm emission was r ecorded. Each cancer was subsequently biopsied and assessed for histol ogical differentiation by a pathologist who was blinded to NCF analysi s. Considerable variation in spectral characteristics between head and neck cancers was identified, which was determined, in part, by NCF ch aracteristics of the normal mucosa from the same patient, Poorly diffe rentiated tumors were more likely than well-or moderately differentiat ed tumors to have lower excitation maxima (P < 0.05 by ANOVA). Most si gnificantly, the tumor differentiation status, as well as the probabil ity of demonstrating recurrent disease, could also be related to the N CF characteristics of the patient's normal mucosa from the same site w ithin the upper aerodigestive tract. NCF analysis may represent an eff ective tool to identify biological characteristics of head and neck tu mors in vivo without the need for invasive biopsies, Results suggest t he need to explore the determinants of NCF characteristics expressed b y clinically normal mucosa.