Plexiform ameloblastoma presenting as a sinonasal tumor.
ABSTRACT Ameloblastomas are the most frequent odontogenic tumours, accounting for 1% of all tumours of the maxilla and mandible. Sinonasal ameloblastomas are most common between the ages of 55 and 65, and mandibular ameloblastomas between 40 and 50. Incidence is higher in males than in females, and there are no differences between races. These locally aggressive tumours originate in the mandible in 80% of cases and in the maxilla in 15-20%. We report an unusual primary nasosinusal ameloblastoma presented in a 68-year-old male. The tumour was completely resected by (para)lateral rhinotomy and treated with postoperative radiotherapy. Histological analysis demonstrated a plexiform ameloblastoma. The patient remains well without disease after 50 months of postoperative follow-up.