Radiation-induced cancers are fortunately a very rare complication of radiotherapy for cancers. Sagerman, however, reported 21 cases in a series of 243 patients with retinoblastomas, examined after a period of at least 5 years, and 6 cases were observed in a similar series of 112 children seen at the Curie Institute. This report describes 10 cases of irradiation-induced cancers of the maxillofacial region seen at the Curie Institute over a period of 30 years. The exceptional nature of this risk is such that it cannot represent a contra-indication to irradiation therapy of a malignant tumor, especially now that low-energy radiation has been abandoned, and with the modern therapeutic procedures available. The risks of cancer are greater, however, after irradiation of benign bone lesions and benign affections of the cervico-facial region. Treatment of these benign affections in children or young adults by low or reduced doses of conventional low-energy radiations should be forbidden, and the indication for treatment with radiations, which must be of high voltage, should be exceptional.