Dynamic susceptibility contrast‑enhanced perfusion magnetic resonance imaging parameters for predicting promoter methylation and prognostic value in newly diagnosed patients with glioblastoma.

O6-methylguanine DNA methyltransferase promoter methylation is an important clinical biomarker of newly diagnosed glioblastoma. Previous radiological studies using dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) perfusion have aimed to predict methylation status non-invasively in gliomas with radiological characteristics. The possibility of predicting methylation status using DSC-MRI perfusion with a radiological approach remains controversial. The present study aimed to evaluate the usefulness of MRI perfusion parameters as non-invasive markers to predict methylation status and prognosis in newly diagnosed glioblastoma patients. Thus, 50 patients with histologically confirmed primary glioblastoma, -wildtype who underwent tumor resection at Osaka University Hospital (Suita, Japan) between January 2017 and January 2023 were included in this study. The mean cerebral blood volume (CBV) ratio (rCBV) and cerebral blood flow (CBF) ratio (rCBF) for tumors with methylation (mean rCBV:2.09 and mean rCBF:3.08) were significantly higher compared with those for tumors without methylation (mean rCBV:1.33 and mean rCBF:1.85; P<0.05). While patients with methylation had longer progression-free survival (PFS) compared with those without methylation (P<0.05), there was no significant difference in OS with or without methylation (P=0.06). By contrast, there was no association between MRI perfusion parameters and OS or PFS in patients with glioblastoma. Furthermore, the association between CBV, CBF, promotor methylation status, OS, and PFS were explored. There was no significant prognostic difference between low vascularity tumors (rCBV <1.3 or rCBF <1.8) with or without methylation. On the other hand, high vascularity tumors (rCBF ≥1.8) with promotor methylation were associated to longer OS and PFS compared with those without. However, there was no association between methylation status and OS or PFS in patients with high rCBV (rCBV ≥1.3). The present study indicated that CBV and CBF could be used to predict the methylation status in glioblastomas. However, the prognostic value of tumor vascularity and methylation status may be limited.