High-grade glioma

A glioma that grows fast. Usually grade 3 or grade 4.

What a high-grade glioma is

A high-grade glioma grows fast. Doctors grade brain tumors from 1 to 4. High grade means grade 3 or grade 4.

It is a group, not one tumor

Several different tumors are high grade, and they are not the same as each other. Grade 4 covers glioblastoma, and it also covers some tumors with an IDH gene change, and some tumors found in the middle of the brain.

This matters when you read research. Two studies can both say "grade 4" and be about different diseases with different treatments. Look for the exact name on your report.

What to ask your team

This is not medical advice. It explains research in plain words. Your care team knows your case. Talk with them before you make any decision about your treatment.

Last reviewed: August 16, 2026

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