Objective: Identify the type and distribution of CD4+ and CD8+ T-lymphocytes in oral mucosa specimens to potentially distinguish underlying alterations or patterns between oral epithelial dysplasia and oral lichen planus.

Methods: For this pilot study, 15 archival tissue samples received at UNC Oral and Maxillofacial Pathology Laboratory, diagnosed as oral lichen planus, moderate to severe epithelial dysplasia and overlapping equivocal cases between dysplasia and lichen planus were selected. Dual staining with CD4 and CD8 antibodies was carried out on each case. Slides were scanned in the Aperio ScanScope FL (Leica Biosystems, Wetzlar, Germany) and archived. Histomorphometric analysis of the cells that expressed biomarkers of in the epithelium and connective tissue regions was performed.

Results: No differences were found in amount and ratio of CD4+/CD8+ lymphocytes between the three groups analyzed. The intraepithelial CD8+ lymphocyte distribution was strikingly different between lichen planus and moderate to severe epithelial dysplasia.

Conclusions: The localization of CD8+ cells can be potentially as an adjunctive diagnostic procedure to distinguish oral epithelial dysplasia from other inflammatory entities such as lichen planus.