Correlation of GFAP to malignancy grade.Grade I higher levels compared to other grades.Grade II significantly higher compared to grade IV.Within grade II glioma GFAP levels were higher in:IDHmut compared to IDHwtATRX loss compared to ATRX retentionNo significant correlation of GFAP to survival after correction for age and tumor grade. Here, ATRX is linked to central nervous system cancer.