Failure of computerized tomography to differentiate between radiation necrosis and cerebral tumour.

Post-radiation cerebral necrosis simulating tumours was found in 2 patients by computerized axial tomography (CAT). The appearance was indistinguishable from that of a recurrent tumour in one patient and a glioma in the second. The significance of the scan findings was only realized after surgery and histological examination. The investigation appears to offer no assistance in differentiating between these conditions.