Postoperative Perfusion Magnetic Resonance Imaging as a Tool for Predicting Survival in Glioblastoma of the Brain

Glioblastoma is the most frequently detected primary brain tumor (pGB), the prognosis of which significantly depends on the magnitude of residual GB (rGB), for which magnetic resonance imaging (MRI) is used in the postoperative period. Purpose: To analyze the data of ASL perfusion MRI (ASL-pMRI) performed prior to adjuvant radiation therapy (aRT), 6 to 8 weeks after resection of pGB, in terms of their prognostic significance for survival in this group of patients. Material and methods: The study included 54 patients (median age ‒ 58 years; gender: 29 men, 25 women). The Karnovsky index in 81.5 % of patients was ≥80 %. To visualize and calculate the dimensions of the rGB, ASL-pMRI was used according to the type of pseudo-continuous three-dimensional marking of arterial spins. The focus/foci of hyperperfusion (CBFmean > 64 ml/100g/min) in the area of the wall of the postoperative cyst were considered as rGB. Results: Survival in the total group of 54 patients with pGB was 18 months (95 % CI:14.23) . The use of ASL-pMRI made it possible to visualize rGB in 37 (68.5 %) patients. The probability of visualization of rGB was significantly higher (p=0.02) in the case of temporal localization of the tumor. Age (HR:1.04; 95 % CI: 1.01‒1.07; p=0.007), the maximum diameter of the rGB (HR:1.04; 95 % CI: (1.01‒1.07); p=0.03) and localization of pGB in the temporal lobe (HR:2.00; 95 % CI: 1.05‒3.80; p=0.034) had a significant negative impact on survival. The use of the multifactorial Cox model showed that only the age ≥60 years (HR:2.78; 95 % CI:1.26‒6.15; p=0.012) and the maximum diameter of rGB ≥25 mm (HR:3.35; 95 % CI:1.36‒8.22; p=0.008) retained their significant negative impact on the survival of patients with pGB. Conclusions: the use of ASL – pMRI 6 to 8 weeks after resection of pGB indicates that the results obtained can become an effective tool for predicting survival in this group of patients.