Abstract
The present report describes two patients with glioblastoma multiforme with the tumour demonstrating low central apparent diffusion coefficient values similar to those found in cerebral abscesses. Although conventional MR images were fairly specific for tumour, the cases illustrate the need for exercising caution when using diffusion‐weighted (DW) MR images for the differentiation of necrotic brain tumours from abscesses. The DW MR imaging information should always be integrated with the conventional spin‐echo MR images.