Fig. 1.

MR images from case 1. (A, C, E, and G) Postcontrast axial T1-weighted MR images. (B, D, F, and H) FLAIR MR images. (A and B) Images taken 18 months after 2 surgeries, radiation therapy, and chemotherapy for recurrent glioblastoma. An inhomogeneously enhancing area with necrosis (arrow in A) was seen posterior to the right frontal lobe surgical cavity, with a large area of surrounding edema (“E” in B). (C and D) Images taken 3 months after beginning bevacizumab therapy. The enhancement posterior to the right frontal lobe surgical cavity had disappeared, and there was a significant decrease in the surrounding edema (“E” in D). (E and F) Images taken 8 months after starting bevacizumab therapy. Subtle areas of nonenhancing FLAIR changes (arrows in F) were seen posterior to the surgical cavity, consistent with nonenhancing tumor. (G and H) Images taken approximately 2 months after stopping bevacizumab. Significant progression of nonenhancing tumor (arrows in H) and spotty areas of enhancing tumor (arrows in G) were seen. The approximate biopsy site is indicated by the white asterisk.