Ameloblastic Fibro-Odontoma: A Case Report and an Alternative Approach to the Pathogenesis of Odontogenic Tumours

OOOO Volume 119, Number 3 IMMUNOHISTOCHEMICAL COMPARISON OF CYCLIN D1 AND SHh IN AMELOBLASTOMA AND KERATOCYSTIC ODONTOGENIC TUMOR Emre Barıs¸1, Burcu Sengüven1, Özgür Ekinci2, Sibel Elif Gültekin1, Manuel Koch3, 1Department of Oral Pathology, Gazi University Faculty of Dentistry, Ankara, Turkey; 2Department of Pathology, Gazi University Faculty of Medicine, Ankara, Turkey; 3Department of Biochemistry, University of Cologne Faculty of Medicine, Cologne, Germany Objective: The different growth mechanism and biologic behavior of the keratocystic odontogenic tumor (KOT) and ameloblastoma (ABL) compared to other odontogenic cyst and tumors might be related to the proliferating capacity of its epithelium. In this study, the aim was to evaluate and compare the distribution and staining intensity of Shh, cyclin D1 and Ki-67 in ABLs and KOTs. Study Design: Tissue microarray samples of 35 ABLs and 40 KOTs were obtained and stained immunohistochemically. Results: Shh was expressed more intensely in peripheral cells and suprabasal layers in ABLs and KOTs, respectively. The highest expression of cyclin D1 and Ki-67 positive cells were seen in the parabasal layer of KOTs, peripheral cells of follicular ABLs and all layers of unicystic ABL. Conclusions: The aggressive of KOT might be related to the state of expression of cyclin D1 and Shh in the epithelium of this cyst. Keywords: ameloblastoma, keratocystic odontogenic tumor, Shh, Cyclin D1

CASE REPORTS OF THREE PATIENTS WITH LIPOMAS IN THE ORAL CAVITY Deniz Tuncel, Tulay Basak, Gulcin Eken, Suleyman Ozdemir, Fevziye Kabukcuoglu, Sisli Hamidiye Etfal Education and Research Hospital, Department of Pathology, Sisli, Istanbul, Turkey Benign soft tissue neoplasms commonly occur in the oral cavity. Lipoma is one of the benign mesenchymal tumors which rarely occurs in the oral mucosa. About 20% of lipomas are seen in the head and neck region among which oral lipomas take place only 1-4% of all lipomas. They occur as slow growing, painless, asymptomatic submucosal masses which can cause speech, mastication and denture problems if only they extend to large sizes. Surgical excision is the proper choice of treatment. In the histopathological evaluation, most oral lipomas are composed of circumscribed mass of mature fat cells with varying number of collagen fibers mixing through the lesion and supporting small blood vessels. Here we present three cases with oral lipomas to emphasize this rare entity. Keywords: oral, lipoma, benign

AMELOBLASTIC FIBRO-ODONTOMA: A CASE REPORT AND AN ALTERNATIVE APPROACH TO THE PATHOGENESIS OF ODONTOGENIC TUMOURS Fatma Canan Alatlı1, Vakur Olgaç1, Nihan Aksakallı1, Merva Soluk Tekkes¸in1, Mehmet Ali Erdem2, Eda Kaya2, Ays¸egül Erten2, 1Istanbul University, Institute of Oncology, Department of Tumour Pathology; 2Istanbul University, Faculty of Dentistry, Department of Oral Maxillofacial Surgery, Istanbul, Turkey

ABSTRACTS Abstracts e197 Odontogenic tumours are neoplasms consisting of odontogenic epithelial and mesenchymal tissues seen in odontogenesis. Mixed odontogenic tumours are relatively rare. Their pathogenesis follow a parallel and very similar pathway to normal odontogenesis. Ameloblastic fibro-odontoma is a mixed odontogenic tumour representing the stage of odontogenesis just before the fully developed tooth, consisting of ameloblasts, odontogenic mesenchyme, dentine, cementum and enamel. A case of ameloblastic fibro-odontoma in the right maxillary premolar and molar region of a 5 year old male, is presented. A swelling and a fibrotic area was observed in the related toothless mucosa. Radiology revealed a multilobular mass inclosing the germinal permanent teeth and extending to the maxillary sinus. The mass was excised and examined histopathologically. Microscopical appearance showed odontogenic mesenchymal tissue with groups and strings of primitive odontogenic epithelium, differentiating to ameloblastic cells in some areas, and a primitive toothlike structure consisting of enamel, dentine and cement tissues. Keywords: Odontogenic tumours, odontogenesis, ameloblastic fibro-odontoma, ameloblastic cells

A DOCUMENTATION OF ODONTOGENIC LESIONS IN TURKEY: 44 CASES Demet Etit1, Fulya Cakalagaoglu1, Arzu Avci1, Fikret Dirilenoglu1, Sedat Ozturkcan2, 1Department of Pathology, Izmir Katip Celebi University Ataturk Research and Training Hospital, Izmir, Turkey; 2Department of Otorhinolaryngology, Izmir Katip Celebi University Ataturk Research and Training Hospital, Izmir, Turkey Objective: Odontogenic lesions are cysts or tumors that develop in jawbone or the soft tissues in mouth. Odontogenic cysts are characterized by epithelium lining a collagenous cyst wall. Radicular cyst is the most common odontogenic cyst. Odontogenic tumors derives from epithelial, mesenchymal or mixed elements that are part of the tooth-forming apparatus. Ameloblastoma is the most common odontogenic tumor. Study Design: A retrospective survey of odontogenic lesions was carried out by using related key words on the hospital information management software system between the years 2005-2012 in our institution. Results: A total of 44 patients were found to have odontogenic lesions. 21 of them were female, 23 were male. 22 of them were tumoral and 22 were cystic lesions. The most common tumor and cyst were ameloblastoma (13) and radicular cyst (14), respectively. Conclusions: As in the literature, the most common odontogenic lesions were ameloblastoma and radicular cyst in our series. Keywords: odontogenic lesion, radicular, cyst, tooth, oral, odontogenic tumor

PRIMARY NON-ODONTOGENIC INTRAOSSEOUS LESIONS OF THE JAWBONES: OUR EXPERIENCE FOR 14 YEARS Arzu Avcı, Demet Etit, Fulya Çakala gao glu, Ahmet Emre Yenipazar, Department of pathology, Ataturk Research and Training Hospital, Izmir, Turkey