Method: Immunohistochemical analysis of 17 dentigerous cysts (DC), 22 keratocystic odontogenic tumors (KOT) and 19 unicystic ameloblastoma (UA) was performed, in order to describe and compare cell proliferation rate, expression of syndecan-1 (CD138), density and location of mast cells, angiogenesis through expression of vascular endothelial growth factor, vascular microdensity and expression of the molecular triad RANK, RANKL and Osteoprotegerin (OPG). Immunostaining was analyzed and quantified using ImajeJ® program. Statistical analysis was performed using Chi-square, Pearson, Kruskal Wallis, Tukey and Spearman Rho tests. Pvalues<0.05 were considered statistically significant.
Result: KOT showed the highest rate of cell proliferation among all lesions (p<0.0001) and increased expression of Syndecan-1 (p=0.0093), while UA showed loss of expression of Syndecan-1 and a lower rate of cell proliferation compared to KOT (p=0.0202). Also, UA showed augmented RANKL-positive cell in the epithelium and stroma. Regarding to VEGF expression, KOT showed statistically increased angiogenesis index compared to UA (p= 0.0225), however no significant differences were found in CD34 expression or tryptase (p> 0.05). Finally, DC showed the lowest expression of all factors analyzed.
Conclusion: KOT demonstrated a higher growth rate compared to the AU. On the other hand, UA showed an augmented invasiveness profile. Unlike these tumors, DC showed lower expression of factors analyzed which explains its rather slow and expansive growth.