[Giant-cell tumor of bone].

Giant-cell bone tumors are a rare entity. Only 7.5 to 15% are malignant tumors and correspond to 0.5% of all primary malignant bone tumors. This case report has an unusual localization (ischium) for this kind of tumor (+/- 0.6%). The patient was treated with radiotherapy alone, because local extension of the disease would require very aggressive surgery with functional implications. Ten years after treatment, the patient is alive without clinical evidence of disease, and without functional impairments.