# The impact of postoperative ischemic changes on survival outcomes in IDH-wildtype glioblastoma

## TL;DR

This study found that larger areas of reduced blood flow after surgery are linked to shorter survival in patients with a specific type of brain tumor called IDH-wildtype glioblastoma.

## Contribution

The study shows that postoperative ischemia independently predicts survival in IDH-wildtype glioblastoma patients.

## Key findings

- Large infarcts were associated with shorter overall survival (14.0 months) compared to smaller infarcts or none/rim-only.
- Infarct volume was independently linked to reduced overall survival in multivariable models.
- Large infarcts remained predictive of shorter progression-free and overall survival when modeled categorically.

## Abstract

BackgroundGlioblastoma (GBM) is an aggressive brain tumor. The authors of this study wanted to find out whether areas of reduced blood flow, called ischemia, that appear after surgery affect how long people live with this disease. To do this, they reviewed scans from 451 patients taken within three days after tumor removal and measured the size of any new areas with poor blood supply. Their results showed that larger areas of ischemia were linked to shorter survival. The prognostic relevance of postoperative ischemia in GBM remains unclear. This study investigated the association between infarct volume and survival in patients with Isocitrate Dehydrogenase (IDH)-wildtype GBM.

We retrospectively reviewed 451 patients with IDH-wildtype GBM who underwent resection between 2013 and 2024 and had diffusion-weighted imaging within 72 h postoperatively. Ischemic changes were defined as new areas of diffusion restriction and stratified into none/rim-only, small (<5 cm³), and large (≥5 cm³) infarcts. Progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan–Meier and Cox regression models adjusted for age, preoperative KPS, tumor size, extent of resection, MGMT status, adjuvant therapy, and postoperative deficits.

Large infarcts were associated with shorter median PFS (7.0 months [95% CI: 5-9]) and OS (14.0 months [95% CI: 9-18]) compared to small infarcts and none/rim-only (PFS: P = .07; OS: P = .001). In multivariable models, infarct volume was independently associated with reduced OS (per cubic centimeter increase, HR = 1.02, 95% CI: 1.01-1.032; P = .003), while its association with PFS did not reach statistical significance (HR = 1.01, 95% CI: 1.0-1.02; P = .13). When modeled categorically, large infarcts remained predictive of shorter PFS (HR = 1.4, 95% CI: 1.01-1.9; P = .04) and OS (HR = 1.7, 95% CI: 1.2-2.4; P = .001).

Infarct volume is independently associated with survival in IDH-wildtype GBM. These findings highlight the clinical relevance of postoperative ischemia and may point toward ischemia-related mechanisms as targets for future therapeutic investigation.