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In the recent years, there has been growing interest in the common use of laser-induced autofluorescence (LIAF) and
reflectance spectroscopy (RS) to differentiate disease from normal surrounding tissue - so called optical biopsy method.
Painless, instant diagnoses from optical biopsies will soon be a reality. These forms of optical diagnoses are preferable to
the removal of several square millimeters of tissue surface - common in traditional biopsies - followed by delays while
samples are sent for clinical analysis. The goal of this work was investigation of cutaneous benign and malignant lesions
by the methods of LIAFS and RS. A nitrogen laser at 337 nm was applied for the needs of autofluorescence excitation.
Broad-spectrum halogen lamp (from 400 to 900 nm) was applied for diffuse reflectance measurements. An associated
microspectrometer detected in vivo the fluorescence and reflectance signals from human skin. The main spectral features
of benign lesions - compound nevus, dysplastic nevi, heamangioma and basal cell papilloma and malignant lesions - pigmented, amelanotic and secondary malignant melanoma, as well as basal cell carcinoma are discussed and their
possible origins are indicated. Spectra from healthy skin areas near to the lesion were detected to be used posteriori to
reveal changes between healthy and lesion skin spectra. Influence of the main skin pigments on the spectra detected is
discussed and evaluation of possibilities for differentiation between malignant and benign lesions is made based on their
spectral properties. This research shows that non-invasive and high-sensitive in vivo detection by means of appropriate
light sources and detectors should be possible, related to real-time determination of existing pathological conditions.
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