Table 1.

Traditional glial tumor response criteria.

Response category	Categorization criteria
Complete response	Disappearance of all enhancing tumor on consecutive CT or MRI scans at least 1 month apart and patient taken off steroid therapy, and neurologically stable or improved
Partial response	Reduction in size of enhancing tumor by ≥50% on consecutive CT or MRI scans at least 1 month apart, steroid therapy stable or reduced and patient neurologically stable or improved
Progressive disease	Increase in size of enhancing tumor or any new tumor by >25% on CT or MRI scans, with steroid therapy stable or increased, or patient neurologically worse
Stable disease	All other situations