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Wide-filed autofluorescence examination is currently considered as a standard of care for screening and
diagnostic evaluation of early neoplastic changes of the skin, cervix, lung, bladder, gastrointestinal tract and
oral cavity. Naturally occurring fluorophores within the tissue absorb UV and visible light and can re-emit
some of this light at longer wavelengths in the form of fluorescence. This non-invasive tissue
autofluorescence imaging is used in optical diagnostics, especially in the early detection of cancer. Usually,
malignant transformation is associated with thickening of the epithelium, enhanced cellular density due to
increased nuclear cytoplasmic ratio which may attenuate the excitation leading to a decrease in collagen
autofluorescence. Hence, dysplastic and cancerous tissues often exhibit decreased blue-green
autofluorescence and appear darker compared to uninvolved mucosa. Currently, there are three commercially
available devices to examine tissue autofluorescence in the oral cavity. In this study we used the oral cancer
screening device IdentafiTM 3000 to examine the tissue reflectance and autofluorescence of PML and
confounding lesions of the oral cavity. Wide-field autofluorescence imaging enables rapid inspection of large
mucosal surfaces, to aid in recognition of suspicious lesions and may also help in discriminate the PML (class
1) from some of the confounding lesions (class II). However, the presence of inflammation or pigments is
also associated with loss of stromal autofluorescence, and may give rise to false-positive results with widefield
fluorescence imaging. Clinicians who use these autofluorescence based oral cancer screening devices
should be aware about the benign oral mucosal lesions that may give false positivity so that unnecessary
patient's anxiety and the need for scalpel biopsy can be eliminated.
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