Negative autofluorescence in benign exophytic lesions highly suspicious for malignancy: importance of the tool as a rapid screening method for lesions requiring biopsy.

Autofluorescence (AF) is a system based on the physiological presence of endogenous fluorochromes in the oral mucosa that change concentration in neoplastic tissues. When exposed to 450-470 nm-blue light, normal tissues emit a light green fluorescence, whereas pre-neoplastic and neoplastic tissues show a loss of AF, so they appear as dark green/black areas when viewed through appropriate wavelength-filtering eyewear. Benign reactive lesions of the oral cavity can sometimes enter the differential diagnosis with malignant tumors. We present two clinical cases of irregular exophytic highly suspicious lesions in which the use of autofluorescence played a decisive role in the differential diagnosis.