Metastasizing ameloblastoma

A case of malignant ameloblastoma with widespread, indolent metastases is reported and 42 previously published cases of metastasizing ameloblastoma are reviewed. The disease-free interval (DFI) between diagnosis of tumor and appearance of metastasis in 43 patients is 9 years. The median survival time after metastasis is 2 years. Most metastases were in the lung. Although the biologic behavior of ameloblastomas cannot be predicted on the basis of morphology, metastasis appears to follow multiple recurrences. Early adequate resection of the primary to avoid repeated surgical procedures is advocated to prevent tumor spread. Surgical removal is preferred for treating metastasis. Although the response to radiation cannot be predicted, radiation should be used to treat lesions not amenable to surgical removal. Disseminated ameloblastoma does not appear to respond to chemotherapy.