Abstract

Tissue autofluorescence for detecting early oral cancer

Martin Scheer, Jörg Neugebauer, Joachim E. Zöller
To assess the malignant potential of clinically suspicious oral lesion an incisional biopsy is recommended in most cases. In recent years adjuvant diagnostic procedures as brush biopsies and toluidin blue staining have been advocated in order to avoid unnecessary invasive procedures and screen the oral cavity for clinically unsuspicious malignant lesions. Since most cases of early cancer will be diagnosed in the dental office a non-invasive fast and cost effective method is needed for screening the oral mucosa for malignant conversation of suspicious and non-suspicious mucosa lesions. Tissue autofluorescence in the oral cavity can be generated by illumination with monochromatic light. Structural and biochemical changes in the mucosa lining and submucous tissue that are not detectable by normal illumination will alter tissue fluorescence significantly and can be enhanced for detection. Areas with loss of tissue autofluorescence are suspect for malignant transformation. Recently a specialised device for detecting malignant or dysplastic lesions called VELScope (Visually Enhanced Lesion Scope) was introduced into the market. Our first experiences with this device consisting of a light source and handpiece revealed that it is easy to handle in the oral cavity. Lesions with fungal or bacteria infection, the dorsum of the tongue as well plaque will show a orange coloured, speckled appearance cause of porphyrins produced by fungus or bacteria. False positive loss of autofluorescence can be caused by traumatic injuries with submucous bleeding as well as lesions with increased blood supply. A reevaluation of the lesions two weeks later is recommended.

Using a tissue autofluorescence for screening the oral cavity for early cancer seems to be a promising approach. However the systematic and comprehensive examination of the oral mucosa especially in smoking patients should be the first diagnostic procedure. The loss of tissue autofluorescence should be carefully evaluated because up to now there is only limited data about the incidence in other benign mucosa conditions for example lichen ruber. Additionally controlled prospective trials were needed to analyse the significance of this new diagnostic tool in a non-selected patient group.