Radiation therapy is a core treatment for many gliomas. It uses precisely targeted high-energy beams to damage the DNA of tumor cells, stopping them from growing and dividing. Knowing how it works can ease the uncertainty of starting treatment.
How it works Tumor cells are generally less able to repair radiation damage than healthy cells. By delivering radiation in many small daily doses (fractions), radiation oncologists maximize damage to the tumor while giving normal brain tissue time to recover between treatments. Modern techniques shape the beams precisely around the tumor to spare healthy brain as much as possible.
A typical course For higher-grade gliomas, radiation is often given five days a week for several weeks (commonly around six weeks), frequently together with temozolomide chemotherapy. Each daily session takes only minutes, and the radiation itself is painless and invisible — like getting an X-ray. The most time-consuming parts are the planning visit and the brief daily setup. Before treatment starts, you'll usually have a planning session that includes a custom mesh mask to keep your head perfectly still and a planning CT/MRI to map the exact target.
What to expect day to day Side effects build up gradually over the course and are covered in detail in their own article, but commonly include fatigue, some hair loss in the treated area, and scalp changes. Many people continue working or daily activities, especially early on, though fatigue often increases over time.
Types of radiation Most glioma radiation is external beam (usually a form of intensity-modulated radiation). Some situations use specialized approaches such as stereotactic radiosurgery (highly focused radiation, sometimes used for small or recurrent lesions) or proton therapy (which can spare more surrounding tissue, sometimes used in children). Your radiation oncologist chooses the approach based on your tumor.
A practical tip: the daily routine of radiation can feel relentless, but it's also finite and structured. Many patients find comfort in the rhythm and in the radiation therapy team they see every day. Ask your team how long your course will be, what side effects to expect, and how to manage fatigue.