Abstract 3256: Variation in treatment of severe oral dysplasia: Knowledge translation in the COOLS trial points to a pressing concern
Authors: Rosin Miriam P. , Corbett Kitty K. , Jiang Huijun , Lubpairee Tarinee , Poh Catherine F. , Zhang Lewei 
Published: May 2015

Purpose: Oral severe dysplasia is a high grade precancerous lesion for which there is limited knowledge on effective treatment and outcome. The Canadian Optically-guided approach for Oral Lesions Surgical (COOLS) Trial, funded by Terry Fox Research Institute, is an ongoing Phase III clinical trial assessing the clinical, molecular and cost-efficacy of fluorescence visualization (FV)-guided surgery to reduce local recurrence of high-risk oral lesions: 140 patients will have high-grade lesions, the rest invasive cancer. One critical gap, identified by COOLS’ knowledge translation component, is the lack of information on treatment practices and outcomes for patients with primary severe dysplasia outside of the trial. The purpose of this study is to establish an evidence base about variation in treatment and outcomes.

Methods: We are extracting primary data on practice variation and patient outcomes from available data sources in the study sites across Canada (chart review, pathology reports and cancer registries, reports of cohort databases). This information will be supplemented via other knowledge translation methods including literature review and knowledge synthesis, and key stakeholder interviews and focus groups.

Results: We report here on file review of 106 primary oral severe dysplasia in longitudinal follow-up in British Columbia (BC) for outcome outside of the COOLs trial. Follow-up was standardized for this cohort; treatment was at discretion of the attending clinician. There was considerable variability in treatment. When treated, the lesion tended to be excised conservatively before (2004), when FV began to be used in BC clinics, but wider margins were more common thereafter. When severe dysplasia were not treated (n=55), prognosis was poor: 5-year progression rate was 50.1% (31.2%-63.9%); when the lesion was removed conservatively (before 2004, n=7), the rate was worse (58.3%, Cl: 0%-84.1.1%)), and when the lesion was more aggressively removed (after 2004, n=42), the rate was significantly improved (9.4%, Cl: 0%-32.3% P = 0.002).

Conclusion: A knowledge translation project turned up research-to-practice variation in the treatment of severe oral dysplasia and an association with patient outcomes. Extension of this study to all COOLS sites will assess whether such variation in surgical practice for severe oral dysplasias, and associated outcome effects, is widespread. We support greater attention to these issues, and dialogue and deliberation among key stakeholders to establish consensus about best treatment of high-grade oral dysplasias and priorities for further research.

Citation Format: Miriam P. Rosin, Kitty K. Corbett, Huijun Jiang, Tarinee Lubpairee, Catherine F. Poh, Lewei Zhang. Variation in treatment of severe oral dysplasia: Knowledge translation in the COOLS trial points to a pressing concern. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3256. doi:10.1158/1538-7445.AM2014-3256