Microvessel density as a prognostic and predictive biomarker in newly diagnosed glioblastoma: correlations with radiological features and bevacizumab efficacy.

Purpose: This study aimed to evaluate the prognostic significance of microvessel density (MVD), assessed by CD34 immunohistochemistry (IHC), and its correlation with radiological features and bevacizumab (BEV) treatment efficacy in newly diagnosed glioblastoma.

Methods: We retrospectively analyzed 41 patients with newly diagnosed glioblastoma. MVD was quantified using CD34 IHC, and patients were stratified into low and high MVD groups according to the cutoff value determined by receiver operating characteristic curve analysis (sensitivity, 76.5%; specificity, 75.0%; AUC, 0.725). Radiological characteristics-including relative cerebral blood flow (rCBF), peritumoral edema, and cystic components-were assessed. Survival outcomes were compared using Kaplan-Meier analysis. Treatment responses to temozolomide (TMZ) with or without BEV were evaluated in both MVD groups.

Results: Patients in the low MVD group exhibited significantly longer progression-free survival (PFS, p < 0.001) and overall survival (OS, p < 0.001) than those in the high MVD group. Low MVD was associated with significantly lower rCBF, less peritumoral edema, and a higher prevalence of cystic components. All six cystic-type cases were found in the low MVD group and showed favorable prognosis. The addition of BEV to TMZ significantly prolonged PFS in the high MVD group (p = 0.001) but not in the low MVD group, with no OS benefit observed in either group.

Conclusion: MVD serves as a prognostic biomarker and may help predict BEV treatment efficacy in glioblastoma. Combined with radiological features, MVD assessment could support more individualized therapeutic strategies. Further prospective studies using both CD34 protein and mRNA expression are warranted to validate these findings.