Subventricular zone contacting glioblastoma: MRI features and prognosis

  Background  As the largest concentrated region of neural stem cells in the adult brain, subventricular zone (SVZ) is considered to have a close relationship with the origin of glioma. Several studies have shown that subventricular zone involved glioblastoma at diagnosis is a negative prognosticator of patients’ survival.

  Objective  To study the MRI features of subventricular zone involving glioblastoma and its influence on patients’ survival.

  Methods  Patients with glioblastoma who underwent surgical treatment in the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2018 were included. Clinical and imaging data were collected, then telephone follow-up was conducted to obtain overall survival and progression-free survival. Imaging features of SVZ involved glioblastoma and the influence of MRI subventricular zone involvement on patients’ survival were analyzed.

  Results  A total of 134 patients were included in this study. Among them, there were 54 males and 80 females, 27 cases were over 65 years old, and 107 cases were under 65 years old. There were 35 cases (26%) in the SVZ involved group and the other 99 cases (74%) belonged to the uninvolved group. Statistical analysis showed that the SVZ involved group appeared to have less cystic changes in the tumor (32.3% vs 51.4%, P=0.045), tumor growth crossing the midline (94.3% vs 60.6%, P＜0.001), multifocal lesions (34.3% vs 8.6%, P=0.003) and larger tumor diameter (5.88±1.27cm vs 3.32±1.62cm, P＜0.001). The median overall survival and progression-free survival were 13 months vs 25 months and 7 months vs 17 months for the SVZ involved group but and the uninvolved group (log-rank P＜0.001, respectively). In multivariate Cox survival analysis, SVZ involvement proved to be an independent risk factor for the survival of glioblastoma patients.

  Conclusion   The MRI features of SVZ involved glioblastomas show less intertumoral cystic transformation, easier to grow across the midline, multifocal lesions and larger tumor diameter. Besides, SVZ involvement in MRI at diagnosis is an independent negative prognostic indicator for the survival of glioblastoma patients.