Malignant ameloblastoma in an 8-year-old child with metastasis to the lung: case report with a clinicopathologic analysis.

Ameloblastomas are rare tumors of odontogenic origin, accounting for 1% of all oral tumors. They are benign, but locally highly aggressive tumors. We report here the unusual case of an 8-year-old patient with multicystic mandibular ameloblastoma, who was submitted to surgery for two relapses in six years and metastasized to the lung two years after initial surgery. The first lesion, diagnosed as follicular ameloblastoma, was treated conservatively with enucleation and curettage. Two years later the tumor relapsed into multicystic granular form. A marginal conservative resection was performed, keeping the basilar contour of the mandible, due to the age of the patient. Three months later, on a routine follow-up examination, a lung metastasis was detected with no signs of tumor in the mandibular bone and the patient was submitted to upper right lobectomy. Three years later a new recurrent tumor was detected in the alveolar process and another marginal resection was performed. Histologically, the tumor showed the follicular growth pattern. After a disease-free period of over five years, the patient was again submitted to surgery for mandibular reconstruction. The mandibular bony defect was filled with iliac bone blocks and four dental implants. He underwent oral rehabilitation with an implant-supported overdenture. With a follow-up period of 22 years since first surgery, the patient is currently free of disease.