Abstract
In the present work, we examine normal and malignant stage IIIB cervical tissue by laser induced fluorescence, with 2 different objectives. (i) Development of the fluorescence spectroscopy technique as a standard optical method for discrimination of normal and malignant tissue samples and, (ii) Optimization of the technique by the method of matching of a sample spectrum with calibration sets of spectra of pathologically certified samples. Laserโinduced fluorescence spectra were measured using samples from 62 subjects at different excitation wavelengths. Principal component analysis (PCA) of spectra and intensity ratios of curveโresolved fluorescence peaks were tested for discrimination. It was found that PCA of total fluorescence at 325 nm excitation gives specificity and sensitivity over 95%. Use of calibration sets of spectra of histoโpathologically certified samples combined with PCA for matching and pass/fail classification of test samples is shown to have high sensitivity/specificity for routine diagnostic purposes as well as for possible staging of the disease. Further, the multiโcomponent origin of the fluorescence spectra is illustrated by curve resolution and fluorescence spectra of separated proteins of tissue homogenates. ยฉ 2006 WileyโLiss, Inc.