Gliomas: predicting time to progression or survival with cerebral blood volume measurements at dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging

Abstract

Purpose: To retrospectively determine whether relative cerebral blood volume (CBV) measurements can be used to predict clinical outcome in patients with high-grade gliomas (HGGs) and low-grade gliomas (LGGs) and specifically whether patients who have gliomas with a high initial relative CBV have more rapid progression than those who have gliomas with a low relative CBV.

Materials and methods: Approval for this retrospective HIPAA-compliant study was obtained from the Institutional Board of Research Associates, with waiver of informed consent. One hundred eighty-nine patients (122 male and 67 female patients; median age, 43 years; range, 4-80 years) were examined with dynamic susceptibility-weighted contrast material-enhanced perfusion magnetic resonance (MR) imaging and were followed up clinically with MR imaging (median follow-up, 334 days). Log-rank tests were used to evaluate the association between relative CBV and time to progression by using Kaplan-Meier curves. Binary logistic regression was used to determine whether age, sex, and relative CBV were associated with an adverse event (progressive disease or death).

Results: Values for the mean relative CBV for patients according to each clinical response were as follows: 1.41 +/- 0.13 (standard deviation) for complete response (n = 4), 2.36 +/- 1.78 for stable disease (n = 41), 4.84 +/- 3.32 for progressive disease (n = 130), and 3.82 +/- 1.93 for death (n = 14). Kaplan-Meier estimates of median time to progression in days indicated that patients with a relative CBV of less than 1.75 had a median time to progression of 3585 days, whereas patients with a relative CBV of more than 1.75 had a time to progression of 265 days. Age and relative CBV were also independent predictors for clinical outcome.

Conclusion: Dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging can be used to predict median time to progression in patients with gliomas, independent of pathologic findings. Patients who have HGGs and LGGs with a high relative CBV (>1.75) have a significantly more rapid time to progression than do patients who have gliomas with a low relative CBV.

Figure 1:

Kaplan-Meier survival curves for progression-free survival in LGG group with low relative CBV (<1.75) and LGG group with high relative CBV (>1.75) show significant difference in time to progression in LGGs stratified according to relative CBV alone (P < .0001). When HGGs were compared, there was a significant difference in progression in HGGs with high relative CBV versus low relative CBV (P < .0001). Among subjects with low relative CBV, there was a significant difference between HGGs and LGGs with respect to progression-free survival (P = .047). Among subjects with high relative CBV, time to progression was not significantly different (P = .266) for LGGs and HGGs.

Figure 2:

Pathologically proved low-grade astrocytoma in 22-year-old man. A–D, Transverse T1-weighted contrast-enhanced MR images (600/14) show subtle contrast enhancement in left frontal lobe. Transverse, B, T2-weighted and, C, intermediate-weighted MR images (3400/19) show slight increased signal intensity involving left frontal lobe, consistent with LGG (arrow). D, Transverse gradient-echo dynamic susceptibility-weighted contrast-enhanced MR image (1000/54) with relative CBV color overlay map shows lesion with high initial perfusion (relative CBV, 3.84), more consistent with HGG. E–G, MR images at 6-month follow-up. E, MR image corresponding to A shows increase in contrast enhancement and progression of disease. F, MR image corresponding to B and, G, FLAIR MR image (9000/110/2500) show increased tumor volume and mass effect behaving more like HGG than true LGG.

Figure 3:

Pathologically proved left temporal AA in 65-year-old woman. A, Transverse T1-weighted contrast-enhanced MR image (600/14) shows enhancing lesion (arrow) in left temporal region, consistent with HGG. Transverse, B, FLAIR MR image (9000/110/2500) and, C, T2-weighted MR image (3400/119) show lesion with abnormal T2 signal intensity involving left temporal lobe. D, Transverse gradient-echo (1000/54) dynamic susceptibility-weighted contrast-enhanced MR image with relative CBV color overlay map shows lesion with low perfusion (relative CBV, 1.2) on initial image. E–H, MR images at 9-month follow-up. E, MR image corresponding to A shows dominant enhancing component to be slightly smaller. Disease remains stable, suggesting true low-grade lesion without malignant transformation or components. F, FLAIR MR image corresponding to B and, G, MR image corresponding to C show that signal intensity abnormality within left temporal lobe has slightly decreased in size. Stable-appearing lesion is in concordance with low relative CBV at presentation. H, MR image corresponding to D shows lesion with stable perfusion (relative CBV, 1.1).

Figure 4:

Kaplan-Meier survival curves for progression-free survival for different histologic tumor types show time to progression to be concordant with histologic tumor type. LGO has longest time to progression, followed by LGA, LGOA, AOA, AA, and GBM.