Dividing patients into groups depending on their astrocytoma malignancy grade, no improvement was observed in the GBM group (83.8% in both groups); however, in the grade II astrocytoma group, PSS demonstrated a solid improvement in predicting two-year survival compared to IDH1 mutational status alone—93.8% vs. 75.00%, respectively. This evidence concerns the gene IDH1 and glioblastoma.