Optically guided surgical approach and the outcome of early-stage oral cancers.

Abstract

1518 Background: It is becoming increasingly apparent that genetically altered cells are often widespread across the mucosa of oral cancer field, extending into clinically and histologically normal tissue. We have demonstrated that direct fluorescence visualization (FV) technology can detect high-risk molecular and histological change in clinically occult margins and that this could be done in a real-time operating room setting. The objectives of this study were 1) To determine the local recurrence-free survival rate (L-RFS) prior to the implementation of FV in surgery (historical group) and 2) To determine the L-RFS after the implementation of FV in Surgery with the comparison between FV- and non-FV- guided groups. Methods: In consecutive fashions, 168 eligible oral cancer cases were identified: 108 from the BC Provincial Cancer Registry from 2000 to 2003 (Historical group) prior to the implementation of FV in surgery and 60 (32 FV-guided and 28 non-FV guided surgeries) from an on-going longitudinal study (LS group) of the BC Oral Cancer Prevention Program between September 2004 and August 2008. The eligible criteria included oral squamous cell carcinoma with less than 4 cm lesion and with intent-to-cure surgical excision alone. L-RFS was defined as the time from surgery to the development of histologically confirmed disease recurrence of severe dysplasia and above lesions. Results: There was no difference in age, gender, anatomical site and follow-up time between historical and LS groups and between FV- and nonFV- guided groups. While the historical group showed 60% L-RFS (n = 65), LS group showed significantly higher L-RFS (88%, p < 0.0001). Strikingly, all the recurrent cases (n = 7) were in the non-FV guided group (25% vs. 0%, p = 0.003). Conclusions: The implementation of novel FV technology has demonstrated its potential to provide a more effective modality to control local recurrence. The data were collected from a small-sized, single- centred study. In order to further validate this promising result, a multicentric phase III randomized trial across Canada is in its planning phase to examine the efficacy of this optical technology. Supported by R01 DE17013 from NIH/NIDCR and CCSRI-20336 from Canadian Cancer Society Research Institute. No significant financial relationships to disclose.