[Malignant odontogenic tumors]

Abstract

Malignant odontogenic tumors are extremely rare. As with benign odontogenic tumors, malignant epithelial odontogenic tumors or odontogenic carcinomas are distinguished from the even rarer mesenchymal ones, the odontogenic sarcomas. The existence of odontogenic carcinosarcomas is not yet acknowledged by the World Health Organization. Odontogenic carcinomas comprise ameloblastic carcinoma (AmCa), primary intraosseous carcinoma (PIOC), clear cell odontogenic carcinoma, odontogenic ghost cell carcinoma (OGCC), and the special case of metastasizing ameloblastoma. Odontogenic sarcomas consist of ameloblastic fibrosarcoma and ameloblastic fibrodentinosarcoma and fibroodontosarcoma. Whereas metastasizing ameloblastoma can be diagnosed only after having metastasized, all other malignant odontogenic tumors present with atypia, increased cellularity and mitoses, and invasion. Odontogenic sarcomas are regarded as low-grade tumors that rarely metastasize. Odontogenic carcinomas, however, especially AmCa, OGCC, and PIOC, are more aggressive, with a 5-year survival rate of about 70% for AmCa and OGCC and a 3-year survival rate of about 37% for PIOC. Radical surgery, eventually in combination with radiotherapy, is the treatment of choice.