LB-151

Purpose:To investigate the value of an easy, hand-held direct fluorescence visualization (FV) device, Velscope, in identifying high-risk oral lesions in Dysplasia Clinics in British Columbia, Canada. Method: 501 patients with a history of oral dysplasia or cancer were recruited from an ongoing Oral Cancer Prospective Longitudinal (OCPL) study and assessed with the VELscope for normal green autofluorescence (FV retention, FVR) or loss of autofluorescence (FV loss, FVL), excluding possible masking factors from recent surgery, trauma, or chronic mucosal inflammatory conditions. Results: 790 lesional fields were examined longitudinally with a total of 2731 examinations. Lesions were clinically apparent in 1727 of these exams: 48% were FVR and 52% FVL. Of interest, in 14% of exams, the FVL was present at former lesion sites that were no longer clinically apparent. In total, 419 biopsies were taken during follow-up: 119 with no dysplasia, 121 low-grade dysplasia, 122 high-grade dysplasia and 57 cancers. FVL was significantly correlated with the severity of histology, present in 24% nondysplastic, 73% low-grade, 94% high-grade lesions and 96% cancers (P < 0.0001). Of the 121 low-grade dysplasia, 14 progressed into high-grade dysplasias (11 FVL), and 7 progressed into cancers (6 FVL). Out of 40 FVL-persistent-former lesion sites, 21 cases have developed the clinically visible lesions during follow-up. Among those biopsied (N=12), the result showed 6 high-grade, 3 low-grade and 3 non-dysplastic. The comparative biopsies were performed on the remaining 19 clinically non-apparent, FVL-persistent lesions, which revealed 6 cancers, 6 high-grade dysplasia, 5 low-grade dysplasia and 2 with no dysplasia. Conclusion: The data support the use of VELscope as an adjunct tool to identify high-risk oral lesions. (Supported by grants R01DE13124, R01DE17013, NIDCR, with salary support to CFP from CIHR)

98th AACR Annual Meeting-- Apr 14-18, 2007; Los Angeles, CA