Glioblastoma multiforme (GBM) brain tumors

No one wants to hear that they have a brain tumor. Glioblastoma brain tumors are cancerous and fast-growing. When you choose Advocate Health Care for your treatment, you’ll have access to all the specialists needed to treat these complex tumors – from neuro-oncology to physical therapy and rehab.

What is a glioblastoma?

Glioblastoma – also known as glioblastoma multiforme (GBM) – is a cancerous tumor of the brain that’s a type of astrocytoma. Both glioblastomas and astrocytomas are part of the brain tumor group called gliomas.

Glioblastomas and astrocytomas grow from star-shaped cells called astrocytes. But a GBM tumor can also have cancerous blood vessels and areas of dead cells inside it.

What makes glioblastomas hard to treat?

Having different kinds of cells is one of the things that makes glioblastomas resistant to treatment, because you need to have treatments for each of the types of cells. Tumors that are made mostly of one type of cell are easier to treat.

Recent research has shown there are four different genetic subtypes that respond differently to treatments. Doctors need to identify which cancer subtype you have to make an effective treatment plan. This can be a complicated process.

Another thing that makes glioblastomas hard to treat is the blood-brain barrier – a feature of the blood vessels in the brain that makes it harder for medicines like chemotherapy to get into the brain.

Glioblastomas also grow finger-like tentacles that reach all around them into other parts of the brain. It can be hard for a neurosurgeon to find all the pieces of glioblastoma cancer and remove them.

Location of glioblastomas

About a third of glioblastomas occur in the front part of the brain. Another third occurs in the sides of the brain. The rest are found in other parts of the brain. It’s rare for them to grow outside the brain or cause cancer in other parts of the body (metastasize).

Glioblastoma risk factors

Undergoing radiation therapy treatment of the head and neck area during childhood increases the risk of developing a glioblastoma tumor. There’s also a higher risk in people with Li-Fraumeni syndrome, neurofibromatosis, Turcot syndrome, Lynch syndrome, or constitutional mismatch repair deficiency syndrome.

Glioblastomas can occur at any age and are most likely to appear between the ages of 65-74. They’re more common in men and White people.

Symptoms of glioblastoma

Glioblastoma symptoms start happening quickly because the tumors grow so quickly that they crowd out healthy brain cells. They also cause swelling from excess fluid which creates more crowding. Some of the most common glioblastoma symptoms are:

Testing to diagnose glioblastomas

Doctors can usually diagnose a glioblastoma from imaging tests. Glioblastomas show up on MRI scans when a contrast dye is added to the area. The cancerous cells pick up more contrast dye than normal cells do, so the tumor appears with many bright areas.

You may have other kinds of MRIs to help with diagnosis and treatment planning. Functional MRI (fMRI) is used to pinpoint whether your tumor is near parts of the brain that control important functions like speech or movement. MRI spectroscopy (MRS) may also be used because it provides information about chemical levels in the brain. Some chemicals are more abundant in tumors, and some are more common in normal brain tissues.

In some cases, your doctor may recommend genetic testing to identify more details about your cancer.

Grading glioblastoma tumors

Doctors describe tumors in terms of grades from 1-4. Glioblastoma tumors are grade 4 tumors – they grow quickly and can spread across the brain.

Some GBM tumors develop from grade 2 or grade 3 astrocytoma tumors. Others have been shown to just appear as grade 4 tumors without evidence of starting out as a lower grade tumor.

Glioblastoma multiforme treatment options

Doctors usually start with surgical treatment of a glioblastoma cancer. Surgery allows them to:

• Gather a tissue sample (biopsy) to confirm the diagnosis
• Relieve pressure on the brain
• Safely remove as much tumor as possible

Your tumor may not be removed if it’s too close to areas of the brain that control important functions like movement or speech. In that case, your doctor will do their best to obtain a biopsy to guide decisions about other glioblastoma treatments.

No two tumors are the same. Your doctor will decide what treatments will work best against your tumor based on its size, location and the type of cells that it has. They’ll also consider your general health when making decisions about treatment.

Other therapies for glioblastoma

Surgery is never considered a cure for a glioblastoma. You’ll almost always receive one or more of the following kinds of therapies after surgery. Therapies offered after surgery are called adjuvant therapies.

• Radiation therapy is one of the oldest kinds of therapy offered for cancer treatment. It focuses radiation on the tumor to shrink it or kill it. Radiation can be offered from outside your body or inside your body.
• Chemotherapy is also offered for cancer therapy. Chemotherapy is considered a medical therapy because it uses medicines that travel through your body. Some chemotherapy is given by pills that you swallow, and some is given by injection into the bloodstream.
• Targeted therapy is a relatively new kind of cancer therapy. It’s based on research that has identified parts of cancer cells called biomarkers. A targeted therapy can make medication go directly to those biomarkers without affecting healthy cells.
• Immunotherapy uses advanced medical knowledge to help your immune system make the cancer cells stop growing or kill them.

Radiation therapy and chemotherapy may be given before surgery to try to shrink the tumor and make it easier to remove. When they’re used that way, they’re called neoadjuvant therapies.

Research continues to be done to find new and better ways of fighting cancer. Your Advocate Health Care doctors may be able to recommend new glioblastoma multiforme treatments available because of that research. You might also be able to participate in clinical trials that could be offering the next big breakthrough in cancer treatment.

Managing side effects from glioblastoma treatment

Radiation and chemotherapy may cause side effects. Your doctor will let you know the side effects for any treatments they recommend.

Just as no two tumors are the same, no two people have the same side effects. We’ll work with you to manage your side effects. It’s an important part of your treatment, so be sure to let your doctor know about any side effects.