. 2019 Feb 26;8(1):CNS28. doi: 10.2217/cns-2018-0007

Table 2. . Criteria for response assessment incorporating MRI and clinical factors.

Criterion	CR	PR	SD	PD
T1-Gd +	None	≥50% ↓	<50% ↓ to <25% ↑	≥25% ↑^†

T2/FLAIR	Stable or ↓	Stable or ↓	Stable or ↓	↑^†

New lesion	None	None	None	Present^†

Corticosteroids	None	Stable or ↓	Stable or ↓	NA^‡

Clinical status	Stable or ↑	Stable or ↑	Stable or ↑	↓^†

Requirement for response	All	All	All	Any^‡

Summary of HGG response criteria	Requires all of the following: complete disappearance of all enhancing measurable and nonmeasurable disease sustained for at least 4 weeks; no new lesions; stable or improved nonenhancing (T2/FLAIR) lesions; patients must be off corticosteroids (or on physiologic replacement doses only); and stable or improved clinically. Note: Patients with nonmeasurable disease only cannot have achieved CR; the best response possible is SD	Requires all of the following: ≥50% decrease compared with baseline in the sum of products of perpendicular diameters of all measurable enhancing lesions sustained for at least 4 weeks; no progression of nonmeasurable disease; no new lesions; stable or improved nonenhancing (T2/FLAIR) lesions on same or lower dose of corticosteroids compared with baseline scan; the corticosteroid dose at the time of scan evaluation should be no greater than the dose at time of baseline scan; and stable or improved clinically	Requires all of the following: Does not qualify for CR, PR or progression; stable nonenhancing (T2/FLAIR) lesions on the same or lower dose of corticosteroids compared with baseline scan. In the event that the corticosteroid dose was increased for new symptoms and signs without confirmation of disease progression on neuroimaging, and subsequent follow-up imaging shows that this increase in corticosteroids was required because of disease progression, the last scan considered to show SD will be the scan obtained when the corticosteroid dose was equivalent to the baseline dose	Defined by any of the following: ≥25% increase in the sum of the products of perpendicular diameters of enhancing lesions compared with the smallest tumor measurement obtained either at baseline (if no decrease) or best response on stable or increasing doses of corticosteroids^†; significant increase in T2/FLAIR nonenhancing lesion on stable or increasing doses of corticosteroids compared with baseline scan or best response after initiation of therapy^† not caused by comorbid events (e.g., radiation therapy, demyelination, ischemic injury, infection, seizures, postoperative changes or other treatment effects); any new lesion; clear clinical deterioration not attributable to other causes apart from the tumor (e.g., seizures, medication adverse effects, complications of therapy, cerebrovascular events, infection, etc.) or changes in corticosteroid dose; failure to return for evaluation as a result of death or deteriorating condition; or clear progression of nonmeasurable disease

^†Progression occurs when this criterion is met.

^‡Increase in corticosteroids alone will not be taken into account in determining progression in the absence of persistent clinical deterioration.

↓: decrease; ↑: increase; CR: Complete response; FLAIR: Fluid-attenuated inversion recovery; HGG: High-grade glioma; NA: Not applicable; PD: Progressive disease; PR: Partial response; SD: Stable disease; T1-Gd +: T1 postgadolinium.