Prognostic vascular imaging biomarkers in high-grade gliomas: tumor permeability as an adjunct to blood volume estimates.

RATIONALE AND OBJECTIVES: Despite recent advances in the treatment of high-grade gliomas, overall survival (OS) remains poor, which underlines the importance of searching for and determining prognostic imaging biomarkers. The purpose of our retrospective study was to correlate patient survival with relative cerebral blood volume (rCBV) and permeability surface area-product (PS) measured using perfusion computed tomography (PCT) in patients with high-grade gliomas.

METHODS: This study was composed of 54 patients with high-grade gliomas (World Health Organization [WHO] grade III, n = 14; WHO grade IV, n = 40) who underwent pretreatment PCT. Kaplan-Meier survival estimates were computed to describe OS for patients with high-versus-low PCT parameters, as well as grade III and IV gliomas.

RESULTS: Differences in OS between high and low rCBV, PS, and rCBV + PS were significant (P < .001) for all high-grade gliomas. After adjustment for WHO grade, rCBV (P = .041) and rCBV + PS (P = .013) estimates remained significant, whereas PS estimates were not (P = .214). PS estimates showed a statistically significant difference for OS in the grade III glioma group (P = .011), whereas for grade IV gliomas, rCBV estimates were statistically significant (P = .019). rCBV + PS was statistically significant for OS in both grade III (P = .001) and grade IV (P = .004) glioma groups.

CONCLUSIONS: Blood volume and permeability estimates measured using PCT can help predict survival in patients with high-grade gliomas. Patients with high PCT parameters showed worse OS compared to the patients with low PCT. Both rCBV and rCBV + PS remained statistically significant even after adjustment for WHO grade, suggesting these may be better predictors of OS than histological grade.