The
odontogenic keratocyst (OKC) is a clinicopathologically distinct form of odontogenic cyst, known for its pathognomonic
microscopic features, aggressiveness and high recurrence rate. The precise nature of the lesion and the reason of its high recurrence rate remain substantially unknown. Considerable debate has existed concerning the ideal treatment modality of these cases. Some authors favor conservative therapy, while others advocate more aggressive forms of treatment. In this study 14 patients with age ranged between 17-48 years were selected. The lesions of OKC were distributed in both jaws. Radiographic examination in the form of panoramic x-ray and axial and coronal CT scans were done preoperatively for all cases. Incisional biopsy was taken for each patient and submitted to immunohistochemical analysis. The aim of this work was to study the immunohistochemical expression of PCNA as a cell proliferation marker and
CD34 as an angiogenic marker, in order to clarify the potential of aggressiveness of these lesions. According to the obtained immunohistochemical findings the lesions were classified to aggressive exhibiting marked angiogenesis and proliferative activities and were treated with resection. Marsupiliazation and / or enucleation with peripheral ostectomy were the line of treatment done for the non aggressive cases. This approach proved successful in clarifying the biologic behavior and the potential features of the lesions that was very significant in selecting the proper treatment modality for each case. The postoperative follow up was uneventful for all patients with no recurrence.