Title:MR Imaging, MGMT Promoter Methylation Features and Prognostic
Analysis of Subventricular Zone Contacting IDH Wild-type Glioblastoma
Volume: 19
Author(s): Ruoyu Liu, Qi Liu, Kai Zhao, Minghang Liu, Guochen Sun and Bainan Xu*
Affiliation:
- Department of Neurosurgery, First Medical Center, PLA General Hospital, 28 Fuxing Rd, Beijing, 100853 China
Keywords:
Subventricular zone, glioblastoma, MR imaging feature, MGMT promoter methylation, prognosis, radiotherapy.
Abstract:
Background: As the largest concentration of neural stem cells in adult brain, the subventricular
zone (SVZ) is considered to be a potential source of glioblastoma (GBM) occurrence in recent
years.
Methods: In this study, 116 patients with glioblastoma treated at PLA General Hospital were retrospectively
reviewed. The features of SVZ contacting glioblastoma were analyzed in terms of MR imaging
and MGMT promoter methylation. We also evaluated the prognostic value of SVZ contacting in
GBM patients.
Results: GBM with SVZ involvement on MRI is more likely to grow across the midline (36.8% vs.
6.9%, P=0.002), more often multifocal lesion (35.6% vs. 6.9%, P=0.003) and have a lower proportion
of MGMT promoter methylation (36.8% vs. 69.0%, P=0.003). The median overall survival and progression-
free survival of patients in the SVZ contacting group were 12 months and 7 months, while 25
months and 17 months in the non-contacting group (P<0.001, respectively). There was no significant
difference in overall survival (P=0.229) and progression-free survival (P=0.808) between patients with
different SVZ contacting regions. Multivariate survival analysis indicated that patients with MRI SVZ
involvement showed worse overall survival (HR=2.060, 95%CI 1.195-3.550，P=0.009) and progression-
free survival (HR=3.021, 95%CI 1.788-5.104，P＜0.001).
Conclusion: This study suggested that MRI SVZ involvement at diagnosis is an independent risk factor
for overall survival and progression-free survival in IDH wild-type glioblastoma patients. Based on
MR imaging, we also found that SVZ contacting glioblastomas had a larger proportion of crossing
midline tumors and multifocal lesions. In addition, patients with SVZ contact in our research presented
a lower proportion of MGMT promoter methylation.
