BACKGROUND: The ameloblastoma is the most common odontogenic epithelial tumor, 
which belong to benign neoplasms that present a painless course, and usually 
occur in the oromaxillo-facial region. Although the histopathological 
manifestation of ameloblastoma is benign, it has unique biological behavior, for 
example local invasion and recurrence repeatedly. A few case of ameloblastoma 
was locally aggressive growth, and rarely metastasis to other tissue, for 
example the lungs, lymph nodes, and spine.
CASE REPORT: A 64-year-old Chinese man, diagnosed with metastatic ameloblastoma, 
was treated with palliative chemotherapy consisting of cyclophosphamide, 
doxorubicin, and cisplatin for six cycles, and radiotherapy for 50 Gy after the 
last cycle chemotherapy. During the surveillance CT scan after the therapy, the 
tissues of the tumor were nearly complete response.
CONCLUSION: The purpose of this study was to report a case of a patient with a 
right mandible ameloblastoma that recurred repeatedly and metastasized into 
bilateral lung. After the chemotherapy and radiotherapy, the tissues of the 
tumor were nearly complete response. This case is interesting because it 
investigated the diagnosis and treatment of the malignancy ameloblastoma, as 
this may help diagnose and treatment for clinician to the metastatic 
ameloblastoma.