Radiation necrosis masquerading as late tumor recurrence: 14 years after combined fractionated stereotactic radiosurgery and conventional radiation therapy

Radiation necrosis is a known sequela of delivering high doses of ionizing radiation to the central nervous system and may be confused with tumor recurrence. Although stereotactic radiation has found increasing application in managing central nervous system malignancies, the imaging appearance of benign tissue several years after such treatment has not been frequently documented in the medical literature. We present the imaging and pathologic features of brain tissue that received fractionated stereotactic radiation by linear accelerator fourteen years earlier.