Nigerian Journal Of surgical Research Vol7 No 1-2 2005: 222 - 225 Case Report Ameloblastic carcinoma: Report of a Case 1,3 JT Arotiba , 2 AZ Mohammed , 3 RA Adebola 4 DS Adeola 4 SO Ajike and 3,5 AH Rafindadi 1 Department of Oral & Maxillofacial Surgery, University College Hospital Ibadan 2,3 Aminu Kano Teaching Hospital, Kano. 3,4 Ahmadu Bello University Teaching Hospital, Kaduna 5 Pathology department Ahmadu Bello Teaching Hospital, Zaria Request for reprints to J. T. AROTIBA,U. I. P. O. BOX 20583,University of Ibadan, Ibadan,Nigeria. E-Mail : jtarotiba@comui.edu.ng / juwonarotiba@yahoo.com Abstract Ameloblastic carcinoma is a rare epithelial odontogenic tumour of the jaws which exhibits cytological features of ameloblastoma and carcinoma. A case of ameloblastic carcinoma in a 52 year old male is reported. Clinical / histological characteristics of this tumour and current knowledge on the classification of odontogenic malignancies are discussed. The importance of including ameloblastic carcinoma in the differential diagnosis of persistent jaw swellings associated with toothache or mobility of teeth or failure of healing of extraction sockets is emphasized. Introduction Ameloblastoma is a benign but locally aggressive neoplasm, which clinically presents as a slowly growing painless swelling of the jaws. Although it is reported to constitute about 1-3% of all jaw tumours and cysts 1 it is the most frequently encountered odontogenic tumor in our environment. 2,3,4,5 Reports from the literature suggest that it is more common in Blacks than in Whites 6,.7 .Its malignant variants are exceptionally rare and may arise de-novo or from transformation of a long-standing primarily benign lesion which has undergone several surgical treatment 8. Although the terms malignant ameloblastoma and ameloblastic carcinoma have been used interchangeably for these variants in the past, it is now generally agreed that malignant ameloblastoma tends to metastasizes in spite of the benign histological characteristics of the primary jaw lesion while ameloblastic carcinoma is an ameloblastoma showing histological evidence of malignancy in the primary recurrent or metastatic lesion 9 . Both variants must also have evidence of rapid clinical growth. In view of the rarity of these tumours, report of cases to encourage documentation of their clinical characteristics and response to treatment has been advocated 10. We present a case of ameloblastic carcinoma in a 52 year- old man which exhibited both histological characteristics of ameloblastoma and carcinoma.Case Report A 52 year old business man presented in our Dental Clinic in February 2002 with a 3 month history of left mandibular swelling. He had earlier on attended a clinic in Saudi Arabia for the same problem and he claimed a biopsy was carried out which indicated an Ameloblastic carcinoma. Swelling was preceded by toothache following which a tooth was removed in September 2001. This resulted in failure of healing of the extraction socket and a soft tissue growth over the socket 2 months post-extraction. Clinical examination revealed a moderate ill-defined, bony hard swelling of the left cheek. The swelling was firm, non tender, not cystic, not warm and not attached to overlying skin. There was no associated anaesthesia. The left submandibular nodes were firm, slightly enlarged but not fix .Intraoral examination also revealed a missing lower left first molar with an exophytic soft tissue growth from the residual socket. Intraoral mandibular swelling extended from the lower left first bicuspid to the retromolar area with bucco-lingual expansion of the jaw. Associated lower left premolars and molars were mobile.Extra- oral plain radiographs revealed a unilocular radioluscency of the left mandibular body with ill-defined margins. Chest Xray and further clinical examination failed to reveal any metastatic disease. A repeat incisional biopsy was done and the initial; report indicated acanthomatocis ameloblastoma but on further a report of ameloblastic carcinoma was reached. Patient was operated under G.A. on 30 th April 2002. A composite block resection of the left mandible from canine region to the ascending ramus