Multiple radiation-induced intracranial lesions after treatment for pituitary adenoma

This 53-year-old man presented with a syncopal episode 31 years after undergoing craniotomy and external-beam radiation for a pituitary macroadenoma. A gadolinium-enhanced magnetic resonance (MR) image of the brain demonstrated a 2.5-cm enhancing mass in the right caudate region that had not been seen on previous studies. A stereotactically guided biopsy procedure was performed to obtain specimens from the mass, which were consistent with ependymoma. The MR image also revealed two additional lesions that appeared to be within the radiation fields: a right temporal meningioma and a left frontal cavernous malformation. A review of the literature found three previous reports in which ependymomas presented after radiation therapy.