Overall survival prediction scale for patients with grade 4 brain astrocytoma

Objective. To create a prognostic scale for overall survival in grade 4 astrocytomas based on molecular biological data. Material and methods. After morphological confirmation of WHO grade 4 astrocytoma (2021 WHO classification criteria), 175 patients were classified as GBM (grade 4) without IDH1 mutations; IDH1 mutation was detected in 25 patients (12.5%; G4 astrocytoma). Molecular biological analysis of IDH1 gene mutations and MGMT promoter methylation was performed in 194 (97%) patients. Results. To study concomitant significance of IDH1 mutation and MGMT promoter methylation in grade 4 gliomas, we created the IDH1/MGMT index(0 — IDH1+/MGMT+; 1 — IDH1/MGMT (+/–); 2 — IDH1-/MGMT-). This predictor was digitized in 194 patients who underwent molecular analysis. The most informative classification matrix according to overall survival was as follows: IDH1/MGMT index (OR=1.712; p=0.0004), REP (OR=1.971; p=0.0001), functional status before microsurgery at the lowest possible level (OR=1.797; p=0.001). Simple summation of numerical indicators for factors 1—3 in each patient allowed us to identify 5 prognostic classes: class 1 (0—1 points), class 2 (2 points), class 3 (3 points), class 4 (4 points), class 5 (5 points). Log-rank criterion for Kaplan-Meier survival curves revealed significant differences between classes (χ2=55.780; p