You just received the diagnosis. Breathe. Start here.

Glioblastoma (GBM) is the most common and most aggressive primary brain tumour in adults. It starts from the brain's own support cells (glia), grows quickly and tends to infiltrate nearby tissue, which makes it hard to remove completely. It does not spread from other organs and it is not contagious: it begins in the brain itself. Understanding this helps explain why treatment usually combines surgery, radiotherapy and chemotherapy.

MGMT is a gene that repairs DNA in cells, including tumour cells. In the molecular report your team looks at whether its “switch” is off (methylated) or on (unmethylated):

• Methylated (switch off): the tumour repairs itself less, and usually responds better to temozolomide chemotherapy. It's a relatively favourable sign.
• Unmethylated (switch on): the tumour defends itself more against that chemo. It does not mean there is no treatment, but it may steer your team toward other strategies or trials.

Always ask for your MGMT status: it genuinely influences decisions.

IDH is another gene that is tested. Since 2021, glioblastoma is defined as IDH-wildtype (“IDH not mutated”). If your report shows an IDH mutation instead, the tumour is classified differently (IDH-mutant astrocytoma), with a different course. So this technical-sounding word actually defines exactly which disease you have. It is worth confirming it.

Next-generation sequencing (NGS) is a test that reads many of the tumour's genes at once, from the sample taken during surgery or biopsy. It goes beyond the basic markers: it gives a fuller molecular picture that can refine the diagnosis, reveal alterations with possible targeted treatment and, above all, open the door to clinical trials for which that data is essential.

NGS is the minimum you should request, but it is not the most complete option. Ideally it should be complemented with a methylation profile (classifies the tumour more precisely and can change the diagnosis) and, when available, RNA-seq (detects gene fusions such as NTRK or FGFR that DNA alone misses and that have specific approved treatments). The more your team knows about your tumour, the more doors open.

It isn't always done routinely, so you can ask your team to request it or to send the sample to a centre that performs it. Es tu derecho.

5-ALA: why it helps. 5-ALA is a liquid taken by mouth a few hours before surgery. It makes tumour cells glow under a special blue light, so the surgeon can tell tumour from healthy brain, hard to see under normal light, because glioblastoma infiltrates the surrounding tissue.

Because of this, fluorescence-guided surgery removes more tumour than white light alone, and removing as much as is safely possible is linked to better outcomes. It is the agent approved specifically for glioblastoma. It does not suit every case. Your neurosurgeon decides.

A fresh frozen sample, not only paraffin. After surgery the priority is diagnosis, so tissue is normally fixed in formalin and embedded in paraffin (FFPE). That works for diagnosis and for many molecular tests, but formalin degrades the tumour's DNA and RNA over time.

A sample frozen fresh at the time of surgery preserves the genetic material far better: it is the gold standard for the most complete molecular studies and is needed for some experimental therapies. It must be requested in advance and kept in the hospital biobank. Make sure it is stored and that you could access it later if needed, for example to send it to another hospital.

Gliadel wafers: ask your surgeon. Gliadel consists of small wafers impregnated with carmustine (a chemotherapy agent) that the surgeon can place directly inside the tumour cavity during resection. The drug is released locally over the following weeks. It is not suitable for every case and not every centre has them available, but if your surgery is planned, it is worth asking whether they might be an option in your case.

Neoadjuvant treatment: is there a trial before surgery? Some clinical trials administer immunotherapy or other agents before surgery (neoadjuvant), because the immune system may respond better while the tumour is still present. If your surgery is not urgent, ask your team whether there is a neoadjuvant trial you could enter. These opportunities exist only before the operation.

Surgical technology: ask what your operating room has. Intraoperative MRI (iMRI), awake surgery with cortical mapping, and neuromonitoring are tools that help maximise safe resection. Not every hospital has all of them. If your centre lacks them, it is a valid reason to request referral to a centre that does.

Standard treatment usually follows a sequence known as the Stupp protocol: surgery to remove as much as safely possible, then radiotherapy together with chemotherapy (temozolomide), followed by maintenance chemotherapy. Tumour Treating Fields (TTFields) and, depending on your case, clinical trials with investigational therapies may be added. Not every path is the same for everyone: your molecular status (MGMT, IDH), the surgery and your general condition shape the plan. Ask about trials early.

TTFields (Tumour Treating Fields) are alternating electric fields that disrupt the division of tumour cells. They are delivered by a portable device worn on the scalp for many hours a day. Added to standard chemotherapy (temozolomide) in newly diagnosed glioblastoma, clinical trials have shown an improvement in survival.

Since August 2025 they are funded by the Spanish National Health System: they were added to the SNS common service portfolio, within a Ministry of Health monitoring study. Adult patients with newly diagnosed glioblastoma who meet the eligibility criteria can access them through designated hospitals. It is a right. Ask your team whether you are eligible and which centre to go to.

Not everyone is eligible, and the device requires commitment (worn most of the day). Your team will assess whether it fits your case.

▶ Denied TTFields? Here's how to fight back

Many hospitals apply internal cost protocols that in practice deny or delay access to TTFields. This is common, but you can and should fight it. A hospital's budget protocol does not override your right to a treatment included in the SNS service portfolio (Royal Decree 1030/2006). The Cohesion Act (Law 16/2003) and the Patient Autonomy Act (Law 41/2002) protect you.

1. Ask for the denial in writing: demand a signed document with explicit reasons. Many hospitals back down when asked to put it on paper.
2. Formal complaint to the hospital: file a complaint with the Patient Services department (SAP). It is registered and requires a response.
3. Patient Ombudsman / Ombudsman: contact the Patient Ombudsman of your autonomous community, or the regional/national Ombudsman. It is free and they can mediate.
4. Complaint to the regional Health Department: file a formal complaint with the health authority of your autonomous community.
5. Complaint to the hospital management: a complaint addressed to the hospital's general manager, copied to the Health Department, usually speeds things up.
6. Go to the media: public visibility (press, TV, social media) creates institutional pressure. No hospital wants to be in the news for denying an approved, funded treatment.
7. Legal action: as a last resort, administrative litigation allows you to legally claim the denied treatment. Life is worth more than any budget criterion.