Conventional laser-induced fluorescence spectroscopy (LIFS) of endogenous chromophores like NADH (Nicotineamide Adenine Dinucleotide, reduced form) and PP IX (Protoporphyrin IX) provides information about the relative amounts of these metabolites in the observed cells. But for diagnostic applications the concentrations of these chromophores have to be determined quantitatively to establish tissue-independent differentiation criterions. It is well- known that the individually and locally varying optical tissue parameters are major obstacles for the determination of the true chromophore concentrations by simple fluorescence spectroscopy. To overcome these problems a fiber-based, 2-channel technique including a rescaled NADH-channel (delivering quantitative values) and a relative PP IX-channel was developed. Using the accumulated information of both channels can provide good tissue state separation. Ex-vivo studies with resected and frozen samples (with LN2) of squamous cells in the histologically confirmed states: normal, tumor border, inflammation and hyperplasia were performed. Each state was represented in this series with at least 7 samples. At the identical tissue spot both, the rescaled NADH-fluorescence and the relative PP IX- fluorescence, were determined. In the first case a nitrogen laser (337 nm, 500 ps, 200 microjoule, 10 Hz) in the latter case a diode laser (633 nm, 15 mW, cw) were used as excitation sources. In this ex-vivo study a good separation between the different tissue states was achieved. With a device constructed for clinical usage one quantitative, in-vivo NADH- measurement was done recently showing similar separation capabilities.