Metastasizing ameloblastoma: a case report

Metastasizing ameloblastoma is a rare, distinct entity under the World Health Organization classification. It is a unique tumor in which metastasis can occur but remains benign. Incidence is considered to be around 2% of reported cases of ameloblastoma, but it could be much lower.

A 30-year-old South Indian woman of Dravidian ethnicity presented in the year 2020 with swelling over the right side of the face. She had a history of recurrent ameloblastoma on the left side of the mandible, for which she underwent multiple surgeries in the past 8 years. A right hemimandibulectomy with a patient-specific implant was performed, and the patient recovered well. She developed hypersensitivity to the implant, which was subsequently removed in 2021. In 2024, she developed a persistent cough with blood-tinged sputum. This did not subside with conservative management and hence was further evaluated. Imaging revealed multiple small, well-defined nodules in both lungs and a branching tubular hypodense lesion in the right parahilar region. Bronchoscopy-guided biopsy was done on the lesion. This was reported as metastatic ameloblastoma. The case was discussed in the multidisciplinary tumor board. It was decided to start the patient on a multikinase inhibitor. However, the patient refused further treatment. The patient is reported to be symptomatically better.

Ameloblastoma is a benign but locally aggressive odontogenic tumor that rarely metastasizes. We report a case with multiple local recurrences over 12 years, currently with pulmonary metastasis. Pulmonary metastasis may be indolent and hence could be misdiagnosed or missed altogether. The degree of suspicion should be higher for patients with recurrences.