ABSTRACT
<p><b>OBJECTIVE</b>To investigate the incidence of radiation-induced maxillary malignancy after radiotherapy for head and neck cancer.</p><p><b>METHODS</b>A total of 273 patients who suffered from osteoradionecrosis after radiotherapy for head and neck cancer were evaluated. Among them, 6 patients were presented with carcinoma and sarcoma arising from maxillary area after radiotherapy.</p><p><b>RESULTS</b>Radiation-induced maxillary cancers happened at a rate of 2.2% in the patients with osteoradionecrosis. There were no statistically significant differences in age, sex and the time interval between the radiotherapy and the cancer occurrence.</p><p><b>CONCLUSIONS</b>Radiation-induced malignancy after radiotherapy for head and neck cancer is mainly located in maxilla, presenting as squamous cell carcinoma or sarcoma of the maxillary sinus.</p>