Evaluation of proliferation activity in dysplastic and nondysplastic oral lichen planus through the analysis of argyrophilic nucleolar organizer regions.

Lichen planus is a mucocutaneous disease, and its potential for malignant transformation is a subject of controversy. We found dysplastic changes in slide review of about 11% of oral lichen planus (OLP) in our previous research. Dysplastic changes can be an initial phase for carcinogenesis. The question is whether it is possible to detect early malignant changes in OLP through the evaluation of proliferation activity. The aim of this study was to compare the cell proliferation activity in dysplastic and nondysplastic oral lichen planus using the quantitative and qualitative analysis of argyrophilic nucleolar organizer region (AgNOR) and to compare candidal infection in these 2 groups. In this cross-sectional, observational, and analytical study, all 14 cases of confirmed dysplastic OLPs and 17 nondysplastic OLPs were stained with an AgNOR technique. Analysis of argyrophilic nucleolar organizer region dots were counted in 100 cells of basal and parabasal layers, and proliferation index (cells with ≥ 5 dots in nucleus) and variations in size of AgNOR dots were also evaluated. Periodic acid-Schiff staining was performed for detection of candidal infection. Mean AgNOR count in dysplastic OLP (2.39 ± 0.2) was more than nondysplastic OLP (2.27 ± 0.59). Candidiasis was found in 14.3% of dysplastic OLP and in 12.5% of nondysplastic OLP. There was no statistically significant difference between the 2 groups in mean AgNOR count (P = 0.62), variation in size of AgNOR dots (P = 1), proliferation index (P = 0.53), and candidiasis (P = 1). The current study showed slight difference in proliferation rate and candidal infection between dysplastic and nondysplastic OLP.