RESUMEN
<p><b>INTRODUCTION</b>The development of secondary tumours as a result of radiation therapy is a rare but serious complication.</p><p><b>CLINICAL PICTURE</b>This is a case report of a 45-year-old Chinese male who developed postirradiation sarcoma of the sphenoid bone in less than 5 years after radiation therapy for Stage T3N1M0 nasopharyngeal carcinoma.</p><p><b>DISCUSSION</b>In the literature, the only case of postirradiation osteosarcoma of the sphenoid bone was after radiation therapy for craniopharyngioma. There was no previously reported case of postirradiation sarcoma of the sphenoid bone after radiation therapy for nasopharyngeal carcinoma.</p><p><b>CONCLUSION</b>This is the first case of postirradiation malignant fibrous histiocytoma of the sphenoid to be reported. Of about 3000 patients treated with radiotherapy for nasopharyngeal carcinoma over a 10-year period in Singapore, only 1 patient developed postirradiation tumour of the sphenoid bone.</p>