Fig 3. Novel therapeutic agents in clinical trials may require use of imaging techniques other than gadolinium-enhancing tumor. Shown here is decreased tumor enhancement but not diameter in a patient with glioblastoma after initiation of a therapy with an inhibitor of VEGF and irinotecan. Note the increase in extent of the infiltrative component of the lesion (lower right). Axial post-gadolinium contrast T1-weighted images (left-hand column) and axial T2-weighted/fluid-attenuated inversion recovery images (right-hand column) were acquired before (upper row) and 7 weeks after (lower row) institution of therapy.