Fluorescence spectroscopy for diagnostic differentiation in uteri's cervix biopsies with cervical/vaginal atypical cytology.

This work aims the diagnostic differentiation of chronic inflammation (CC), low-grade Intraepithelial squamous lesions (LGSIL) and high-grade intraepithelial squamous lesions (HGSIL) in biopsies of cervix of uterus from patients with atypias (ASC-US and ASC-H) and lesions (LGSIL and HGSIL), traced in the cervical/vaginal cytology by using Laser-Induced Fluorescence Spectroscopy (LIFS), with 488 nm excitation wavelength. Ninety seven biopsies from 32 patients with atypical cervical/vaginal cytology were collected. The biopsies were guided by colposcopy and taken at the squamous-columnar junction. Fluorescence emission spectra of each biopsy were collected by means of an optical fiber cable coupled to an argon laser at 488 nm as excitation source and addressed to a spectrograph and CCD camera/controller. Spectra were separated into three groups, CC, LGSIL and HGSIL, based on the cytopathology. It was detected similar mean spectra profiles for CC and LGSIL, and differences for HGSIL. An algorithm was developed for tissue classification based on the intensity of the multiplication of each spectrum by the mean spectrum of each group, searching for a discriminator that would address this spectral difference. The sensitivity and specificity of HGSIL identification, compared to CC and LGSIL was 89% and 100%, respectively. The LIFS using excitation wavelength of 488 nm could be used to differentiate HGSIL lesions from LGSIL and CC inflammation, and could help a precocious and less invasive diagnosis of cervix lesions.