Intraosseous ameloblastoma with a prominent extraosseous component: pitfalls in diagnosis

Head Neck Pathol. 2010 Sep;4(3):192-7. doi: 10.1007/s12105-010-0182-6. Epub 2010 Jun 15.

Abstract

For many years, gingival tumors of what appear to be peripherally located intraosseous ameloblastoma (IA) arising from the alveolar bone surface have often been confused with peripheral ameloblastoma (PA) causing resorption of the underlying bone. We analyzed a series of five cases of ameloblastoma that demonstrated a combined PA and IA architecture. The tumor commonly involved the anterior-premolar area, mostly in the maxilla and mainly in middle-aged men. The clinical presentation was an exophytic gingival mass inferior to which was a small bone defect. The predominant extraosseous component showed a papillary gross surface, reflecting the histologic proof of fusion between the submucosal tumor and the surface epithelium. In addition to the PA-like growth pattern, common to all was the presence of neoplastic destruction of the alveolar process, corresponding to an associated radiolucent lesion. This restrained component was acceptable as IA. In two cases, recurrence was observed deep in the alveolar bone with no involvement of the gingiva. These tumors appear to be IA that arose from the marginal alveolar bone and grew preferentially in the gingiva, forming a PA-like appearance. From diagnostic, therapeutic and prognostic points of view, this type of IA should not be confused with PA.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Aged
  • Alveolar Process / diagnostic imaging
  • Alveolar Process / pathology
  • Ameloblastoma / diagnosis*
  • Ameloblastoma / diagnostic imaging
  • Ameloblastoma / surgery
  • Diagnostic Errors / prevention & control
  • Humans
  • Male
  • Mandibular Neoplasms / diagnosis*
  • Mandibular Neoplasms / diagnostic imaging
  • Mandibular Neoplasms / surgery
  • Maxillary Neoplasms / diagnosis*
  • Maxillary Neoplasms / diagnostic imaging
  • Maxillary Neoplasms / surgery
  • Middle Aged
  • Neoplasm Recurrence, Local
  • Radiography