Fibrosarcoma complicating irradiated pituitary adenoma.

Eight years after radiation therapy (5000 rads of 60Co) for a pituitary adenoma, a patient developed a sellar fibrosarcoma. The tumor had an aggressive growth pattern: it infiltrated the optic nerve, sphenoidal air sinus, hypothalamus, and both cavernous sinuses, where compression of the left internal carotid artery resulted in a massive hemispheric infarction. Surgery was ineffective in arresting rapid growth of the lesion; death occurring 5 months after onset of symptoms.