We describe a large ameloblastic carcinoma of the mandible with multiple pulmonary metastases. The patient was a 62-year-old woman. In March 1994, she underwent enucleation of a tumor in the anterior part of the mandible at another hospital. The histopathological diagnosis was a typical ameloblastoma. She was lost to followup soon after the operation. In March 2008, she was referred to Hokkaido University Hospital. She had a large hemorrhagic tumor, which projected outside of the mouth. Chest radiography revealed many nodular opacities in both lung fields. In May 2008, we performed a segmental mandibulectomy to improve her quality of life. The histological diagnosis was an ameloblastic carcinoma-secondary type, intraosseous. There has been no sign of tumor recurrence for 2 years postoperatively.
