Table 2:

New criteria for response assessment of high-grade gliomasa

Standardization of Imaging Definitions
     Measurable and nonmeasurable disease for contrast-enhancing lesions
        Measurable disease: 2D contrast-enhancing lesions with clearly defined margins, with 2 perpendicular diameters of at least 10 mm, visible on ≥2 axial sections that are preferably, at most, 5 mm apart
        Nonmeasurable disease: either unidimensionally measurable lesions, masses with margins not clearly defined, or lesions with maximal perpendicular diameters <10 mm
    Multiple lesions
        A minimum of 2 (maximum of 5) largest lesions should be measured on the basis of the sum of products of perpendicular diameters
        Enhancing lesions are considered target lesions for evaluation of response
Definition of progression
    ≥25% increase in sum of products of perpendicular diameters of enhancing lesions compared with smallest tumor measurement at reference scan (if no decrease) or best response after initiation of therapy
    Significant increase in T2/FLAIR nonenhancing lesion compared with reference scan or best response
    Clear progression of nonmeasurable disease
    Clear clinical deterioration
Reference MR imaging
    Criteria for determining progression are dependent on the time from initial chemotherapy
    If obtaining the reference MR image immediately postoperative, MR imaging in the first 12 weeks may represent
        pseudoprogression and pseudoresponse
    If obtaining the reference scan after that initial 12-week period, then it reduces the likelihood of confusion with pseudoprogression
    Take note of enhancement outside radiation field; it may indicate progression (Fig 6)
    A reference MR image should ideally be obtained within 24–48 hours after surgery and no later than 72 hours after surgery, to avoid interpretation of postoperative changes as residual enhancing disease
  • a Based on Wen et al 2010.67