Usefulness of objective evaluations by fluorescence visualization device for differentiating between superficial oral squamous cell carcinoma and oral lichen planus

Objective: Various diseases can involve the oral mucosa, which can make diagnosis difficult. Fluorescence visualization (FV) devices allow non-invasive screening for oral squamous cell carcinoma (OSCC). Although its usefulness has been reported using subjective evaluations, this study aimed to clarify its utility in screening oral mucosal diseases using subjective and objective evaluations. Patients and methods: Fifty patients with superficial OSCC or oral lichen planus (OLP) treated at Tokyo Dental College between April 2016 and March 2018 were investigated. Subjective evaluation involved discriminating FV retention from FV loss (FVL), while objective evaluation involved calculation of luminance value (LV) and luminance rate (LR) as luminance of the lesion/luminance of control, and border change rate (BCR) using image-processing software. We calculated the area under the curve (AUC), sensitivity, and specificity using receiver operating characteristic (ROC) analysis. Results: In subjective evaluations, FVL was observed in all cases (p=1.000). In objective evaluations, LV tended to be higher for OSCC than for OLP, but the difference was not significant. LR was significantly higher for OSCC than for OLP. BCR was significantly lower for OSCC than for OLP. In ROC analyses, AUCs for LV, LR, and BCR were 0.613, 0.864, and 0.913, respectively; cut-offs were 97.0, 69.0, and 27.2; sensitivities were 85.0 %, 90.0 %, and 85.5 %; and specificities were 36.7 %, 70.0 %, and 93.3 %. Conclusions: Objective evaluations, such as LR and BCR using the FV device, appear to be useful for discriminating between OSCC and OLP.