Rare case of ameloblastoma with pulmonary metastases

Abstract

Ameloblastoma is a rare low-grade odontogenic tumor of epithelial origin. The World Health Organization (WHO) has defined malignant ameloblastoma (MA) as a histologically benign-appearing ameloblastoma that has metastasized. Treatment of the primary ameloblastoma usually consists of radical excision of the tumor and adjuvant radiotherapy. Chemotherapy should be used to treat metastases due to its indolent clinical course. Presented here is the case of a 43-year-old woman who was admitted to a hospital in 2006 with a large mass involving the neck and left mandible. The mass had formed over years and had been neglected. The woman was diagnosed with a primary ameloblastoma of the mandible. Surgical resection was performed, followed by adjuvant radiotherapy. In September 2016, she was admitted again, and the findings were consistent with metastases of the previously identified ameloblastoma to the lungs. The patient was evaluated for further chemotherapy with 6 cycles of cisplatin at a dose of 100 mg/m² on day 1, 5-FU at a dose of 1000 mg/m²/day on day 1-4 (3 wk), and pegylated filgrastim. The current case represents the classical course of a rare disease, which in this instance involved the common presentation of MA. This case is a valid incidence of MA based on the typical histology, findings from a lung biopsy, the immunohistochemical profile of the tumor, the typical clinical features, and a history of a previous primary disease.

Keywords: Ameloblastoma; ameloblastic carcinoma; metastases.

Figure 1.

Lung metastases in the current case. (A), X-ray, (B), CT.

Figure 2.

Histological slide confirming the metastasis of ameloblastoma. (A), Magnification 80×; (B), Magnification 160×.

Figure 3.

Timeline of the course of disease and the diagnostic and treatment strategy in the current case.