Multiple cysts in the cerebral white matter: A rare complication of whole brain radiation therapy

We describe a patient with multiple cysts in the cerebral white matter, sev eral years after whole brain radiation therapy (WBRT) for a solitary cerebe llar metastasis of a lung carcinoma. MR images of the brain show diffuse wh ite matter changes, 1 year after radiation, and cyst formation in the white matter, starting 3.5 years later. We conclude that cysts in the cerebral w hite matter can be a late stage of white matter damage after whole brain ra diation therapy in long-term survivors with brain metastases.