Fig 1.

A–C, A 48-year-old woman with glioblastoma with a methylated MGMT promoter gene has a remote tumor mass on the contrast-enhanced T1-weighted image (A) immediately after the concomitant chemoradiotherapy. MR perfusion image (B) reflects a slight increase of CBV, indicating an rCBV of 1.41 compared with contralateral white matter. After 4 months' continuation of TMZ, enhancement of the lesion decreases without further treatment, which is compatible with pseudoprogression (C). D–F, A 65-year-old man with glioblastoma with unmethylated MGMT has a progressive enhancing lesion involving on the splenium (D). MR perfusion image (E) demonstrates a high increase of CBV indicating an rCBV of 4.38. After 2 months, the lesion shows stronger enhancement and more enlargements, demonstrating real tumor progression (F).