Improving the detection and triage of oral premalignant lesions in high-Risk clinics and community dental practices

Oral cancer occurs at a cancer site that is easily examined; yet more than 40% of oral cancers are diagnosed at a late stage when the chance of death is high and treatment can be devastating. Although oral cancer screening is part of every oral health professional’s (OHP) training, it is often difficult for OHPs to differentiate high-risk oral premalignant lesions (OPLs) from benign reactive lesions. A primary goal of this thesis was to evaluate two approaches to enhancing visualization of clinical lesions: the application of toluidine blue (TB) stain, used to improve contrast of suspicious mucosal areas in normal tissue (Project 1), and fluorescence visualization (FV), used to identify an alteration to tissue optics that is associated with morphological and biochemical change seen in cancers and premalignant disease (Projects 2 and 4). A second goal was to develop and evaluate an educational strategy for oral cancer screening in community dental clinics aimed at strengthening conventional screening activities and providing a framework for integration and assessment of visualization techniques in community settings (Projects 3 and 4). Studies were conducted on patients within two settings: referral clinics of the BC Oral Cancer Prevention Program (Projects 1 and 2) and community dental clinics in the Vancouver lower mainland (Projects 3 and 4). Use of two settings is important: technology developed within high-risk referral settings needs to be re-evaluated in community clinics where the spectrum of disease is different and expertise is variable. Among key results of these studies were: a strong association between TB positive staining and increased (6-fold) cancer risk for OPLs; an association of FV and high-risk clinical, histological and molecular change; and; identification of barriers and facilitators for oral cancer screening in OHPs with evaluation of a triaging framework to support key decision points in community practices. In summary this thesis data supports the use of TB and FV visualization approaches in high-risk clinics to improve detection of OPLs. In addition, the community studies have produced a framework for transfer of new technology into general dental practice building upon an enhanced triage and referral system.