Glioblastoma: what is the role of radiotherapy?

What makes glioblastoma different?

Glioblastoma is an aggressive malignant tumour that arises in the brain. Its diagnosis depends on imaging and, whenever possible, tissue examination and molecular tests. It should not be confused with meningioma, brain metastases or other gliomas, which may require very different treatments.

Where does radiotherapy fit?

The team first considers whether as much of the tumour as possible can be removed safely. After surgery—or after a biopsy when resection is not suitable—radiotherapy is generally used to treat the area where tumour cells may remain. For patients fit enough to receive it, radiotherapy is commonly combined with temozolomide, a chemotherapy medicine given during and after radiation treatment.

Is the treatment course always the same length?

No. The number of sessions depends on functional status, age, tumour characteristics, previous procedures and the person’s priorities. A shorter treatment schedule may be appropriate for some patients. The decision should not depend on age alone; the team weighs disease control, potential side effects and quality of life.

What may happen on follow-up scans?

MRI follow-up is essential. Early changes caused by treatment can resemble tumour growth, a phenomenon called pseudoprogression. A change on a scan therefore does not always mean that the tumour is worsening; interpretation requires symptoms, serial imaging and sometimes additional tests.

Questions to discuss

Ask about the realistic aims of treatment, whether temozolomide is suitable, the planned number of sessions, symptom management and the next MRI. Outcomes vary greatly, and no treatment guarantees a cure or a particular period of disease control.