Rare Presentations of Delayed Radiation Injury: A Lobar Hematoma and a Cystic Space-occupying Lesion Appearing More Than 15 Years after Cranial Radiotherapy: Report of Two Cases

OBJECTIVE AND IMPORTANCE Radiation vasculopathy and radionecrosis, constituting delayed radiation injury, are rare but recognized complications of radiation therapy occurring at a peak incidence of 3 years after treatment. Little information is available about these complications occurring more than 15 years after radiotherapy and presenting as other than solid intracranial masses. CLINICAL PRESENTATION We describe two patients who presented with space-occupying cerebral lesions. Patient 1 presented as an emergency with a sudden loss of consciousness. Computed tomography revealed a large left intracerebral hemorrhage; cerebral angiography disclosed nothing abnormal, and a primary spontaneous hemorrhage was presumed. Twenty-seven years earlier, this patient had received adjuvant whole-brain and spine radiotherapy and concomitant chemotherapy after excision of a vermis medulloblastoma. Patient 2 presented with a left frontal cystic lesion (presumed malignant glioma) as the cause of personality and behavioral changes for some months. She had previously received external beam radiation for a basal cell epithelioma, which had been excised from her left forehead 19 years earlier. INTERVENTION Both patients recovered well after undergoing craniotomies and removal of their lesions; they were discharged home with no neurological deficit. CONCLUSION Even after long intervals after radiotherapy, it is important to consider radiation vasculopathy and radionecrosis as differential diagnoses of more common conditions. Histological confirmation of a delayed radiation injury in the absence of any evidence of neoplasia or vascular abnormality has allowed appropriate prognosis and management to be formulated with confidence in each of these patients.