 2.0. STUDY TOOL - VELSCOPE We have recently developed a simple hand-held field-of-view device for direct visualization of tissue fluorescence in the oral cavity. This tool is currently commercially available as VELScope LED Med Inc., White Rock, BC. We have begun a longitudinal study to explore the effect of FV in defining the surgical margin on outcome of oral cancer surgery27. Between 2004 and 2008, 60 patients with a 4 cm oral cancer entered the study. Each case was treated with surgical excision alone and was followed for at least 12 months. Thirty-eight patients had FV-guided surgery, with the surgical margin placed at 10 mm beyond the perimeter of autofluorescence loss. The remaining patients control group had the surgical margin placed at 10 mm beyond the tumor edge defined by standard white-light examination. Among those, 7 of the 60 cases 12 have developed a recurrence of severe dysplasia, carcinoma in situ or squamous cell carcinoma at the treated site, all in the control group 25 versus 0, P 0.002. These data suggest the potential utility of autofluorescence changes within this clinical setting. There is a need to design a larger scaled randomized controlled clinical trial to confirm the efficacy of FV-guided surgery. 