Immunohistochemical expression of Ki-67 and Glypican-3 to distinguish aggressive from nonaggressive benign odontogenic tumors.

Background: The benign neoplasms are normally slow growing, indolent with no invasive potential. However, there exist a few locally aggressive benign odontogenic tumors that have a tendency to invade and deform the surrounding structures. The exact reason for the aggressiveness of these benign neoplasms remained an enigma. Their biology and clinical expression can often be destructive and ominous. An appropriate treatment protocol needs to be followed to combat the high recurrence rate and aggressiveness of these entities. Aggressive and noniaggressive epithelial odontogenic tumors were analyzed immunohistochemically with Ki-67 and glypican 3 (GPC3).

Materials And Methods: Fifty-nine cases of tumors were divided into aggressive odontogenic tumors (20 solid ameloblastomas, four unicystic ameloblastoma, and 28 keratocystic odontogenic tumors) and nonaggressive odontogenic tumors (five adenomatoid odontogenic tumors and two calcifying cystic odontogenic itumors).

Results: Statistical analysis using Pearson correlation showed Ki-67 to be a better marker for differentiating aggressive from nonaggressive odontogenic tumor as compared to GPC3 (P < 0.001, highly significant), whereas among aggressive tumors, GPC3 turned out to be more useful as compared to Ki-67 (P < 0.001, highly significant).

Conclusion: The present study provides an insight into the different biological behavior of odontogenic tumors, which can thus be helpful in determining the therapy strategies for more aggressive odontogenic tumors.