Isocitrate Dehydrogenase Wild-type Glioblastoma Resection Under Fluorescein Sodium and White Light Guidance Based on Response Assessment in Neuro-Oncology Resect Criteria

Operative Neurosurgery 30:861–869, 2026

This study evaluates sodium fluorescein–guided resection versus white‑light surgery in isocitrate dehydrogenase wild‑type glioblastoma, using RANO resection classes and quantitative MRI volumes to compare residual contrast‑enhanced tumor burden. The retrospective analysis of 162 patients shows significantly lower postoperative CE residual volume and higher complete CE resection rates with fluorescein guidance.

The paper also correlates molecular markers with resection outcomes, finding MGMT promoter methylation associated with higher complete CE resection rates and suggesting fluorescein guidance may particularly improve CE resection across molecular subgroups, while survival differences require longer follow‑up and larger cohorts.

Objective Increase extent of resection of the contrast-enhanced (CE) portion of IDH–wild-type glioblastoma, using the RANO absolute residual-volume resection classes to quantify what sodium fluorescein guidance achieves vs white light (WL) surgery.

Design/measurement Retrospective comparative study of 162 patients (fluorescein 82 vs WL 80), with pre/post-op MRI volumetrics outlined in Brainlab and categorized by RANO EOR classes.

Key EOR result Residual CE tumor volume was lower with fluorescein guidance than WL (median 0.0 cm³ vs 0.5 cm³, P = .023).

Complete CE resection rate Proportion with 0 cm³ residual CE (RANO I + IIA) was higher with fluorescein (62.2%) than WL (42.5%), P = .012.

RANO distribution shift RANO class distribution differed between groups (P = .015), with more IIA and fewer IIB resections under fluorescein guidance.

Non-CE resection No significant between-group differences were found in preoperative CE/NCE volumes or postoperative NCE residual volumes, consistent with fluorescein primarily highlighting BBB-disrupted (enhancing) tissue.

MGMT association MGMT promoter methylation was associated with higher likelihood of achieving nonresidual CE (complete CE resection), P = .005; fluorescein guidance and MGMT status were significant predictors of nonresidual CE.

Survival Overall survival did not significantly differ between fluorescein-guided and WL groups (log-rank P = .15), while MGMT-methylated patients had significantly better survival than unmethylated (P = .019; HR = 0.52).

Volumetric Growth and Growth Curve Analysis of Residual Intracranial Meningioma

Neurosurgery 92:734–744, 2023

After meningioma surgery, approximately 1 in 3 patients will have residual tumor that requires ongoing imaging surveillance. The precise volumetric growth rates of these tumors are unknown.

OBJECTIVE: To identify the volumetric growth rates of residual meningioma, growth trajectory, and factors associated with progression.

METHODS: Patients with residual meningioma identified at a tertiary neurosurgery center between 2004 and 2020 were retrospectively reviewed. Tumor volumewas measured using manual segmentation, after surgery and at every follow-up MRI scan. Growth rates were ascertained using a linear mixed-effects model and nonlinear regression analysis of growth trajectories. Progression was defined according to the Response Assessment in Neuro- Oncology (RANO) criteria (40% volume increase).

RESULTS: There were 236 patients with residual meningioma. One hundred and thirtytwo patients (56.0%) progressed according to the RANO criteria, with 86 patients being conservatively managed (65.2%) after progression. Thirteen patients (5.5%) developed clinical progression. Over a median follow-up of 5.3 years (interquartile range, 3.5–8.6 years), the absolute growth rate was 0.11 cm3 per year and the relative growth rate 4.3% per year. Factors associated with residual meningioma progression in multivariable Cox regression analysis were skull base location (hazard ratio [HR] 1.60, 95% CI 1.02–2.50) and increasing Ki-67 index (HR 3.43, 95% CI 1.19–9.90). Most meningioma exhibited exponential and logistic growth patterns (median R2 value 0.84, 95% CI 0.60–0.90).

CONCLUSION: Absolute and relative growth rates of residual meningioma are low, but most meet the RANO criteria for progression. Location and Ki-67 index can be used to stratify adjuvant treatment and surveillance paradigms.