Lymphangiogenesis in Odontogenic Keratocysts Compared with Dentigerous Cysts

Statment of the Problem: Podoplanin can indicate the lymphangiogenesis. On the other hand, lymphangiogenesis affects the biological behavior of lesions. The clinical behavior of odontogenic keratocysts (OKC) and dentigerous cysts (DC) is different. Purpose: This study aimed to evaluate the immunohistochemical expression of podoplanin and to investigate lymphangiogenesis in OKCs as compared to DCs. Materials and Method: In this experimental laboratory study, sixty paraffined blocks, including 30 OKC and 30 DC samples, were examined in this study, all of which were histopathologically non-inflamed. To evaluate lymphangiogenesis, the immunohistochemi­cal reaction of D2-40 was evaluated via cytoplasmic and membrane staining of lymphatic endothelial cells. The expression of podoplanin in the epithelial cells of two cyst groups was also examined. To analyze the collected data and compare the results between the two groups of cysts, independent samples t-test, Mann-Whitney U test, and Chi-square test were performed in SPSS version 22. The significance level was set at 0.05. Results: The mean lymph node count and podoplanin expression were significantly higher in the OKC epithelium as compared to DC (P 0.001). Based on the results, 90% of OKC samples and 43.3% of DC samples showed grade 3 staining. Conclusion: The rate of lymphangiogenesis and podoplanin expression in the epithelium were higher in OKCs compared to DCs. According to the results, the expression of podopla-nin may be a useful marker for determining the invasiveness and proliferation of OKC.