A Combined Transoral and Transnasal Endoscopic Approach to Resection of Maxillary Ameloblastoma with Extension to the Anterior Skull Base

Ameloblastoma is a rare, odontogenic tumor, which arises from dental epithelium that is of enamel tissue type but does not undergo transformation to the point of enamel formation. The literature sites a predominance of mandibular involvement over maxillary origin by a factor of approximately 4:1. While these tumors are considered benign owing to the fact that they do not metastasize, they are locally destructive. We describe a case of an 86 year old woman who presented with progressive left-sided nasal obstruction and rhinorrhea. Physical examination and imaging revealed tumor filling the left maxillary sinus and nasal cavity with extension to the anterior skull base. A transnasal biopsy was diagnostic of ameloblastoma. The maxillary component of the mass was successfully resected via a transoral left palatectomy. The remainder of the tumor, which filled the left nasal cavity, ethmoid air cells, and frontal sinus was removed through a transnasal endoscopic approach. In this report we review the epidemiology, presenting symptoms, and clinical characteristics of maxillary ameloblastoma and we describe a novel approach to resection of these locally aggressive tumors.