Glioma

Glioma is a family of brain tumors, not one diagnosis. What the family tree looks like. Which page is yours, and what the words on your report mean.

The short version

Gliomaglioma: A tumor that starts in the glial cells. Those are the support cells of the brain and spinal cord. Gliomas are given a grade from 1 to 4. The grade says how the tumor is expected to act. See the glossary is a family name, not a diagnosis. If your paperwork says only "glioma", it has told you the neighborhood and not the address. Your pathology report will have a more exact name on it. That name usually comes with a grade and some gene results. It is what everything else depends on. This page helps you work out which one is yours, then sends you to the right place. If your report uses words you cannot find anywhere, the naming rules changed in 2021. That is covered here too.

What is a glioma?

Your brain has nerve cells, and it has helper cells packed around them. The helper cells are called glial cells. A glioma is a tumor that starts in those helper cells. Gliomas are the most common kind of tumor that begins in the brain itself.

"Glioma" covers a lot of ground. Some grow very slowly. Some grow fast. They are treated differently and they behave differently, which is why the family name on its own cannot tell you much.

The family, roughly

Think of it as a family tree with a few main branches.

• The adult-type diffuse gliomas. This group has just three names in it: astrocytoma, oligodendroglioma, and glioblastoma. Gene results are what tell them apart, not how they look alone.
• Gliomas of the kind usually seen in children. These are a separate group with their own biology. Some grow slowly, some do not.
• Gliomas with a clear edge. Many gliomas spread out into the brain around them. A smaller group sits in a more defined lump, and the word for those on a report is circumscribedcircumscribed: A tumor with an edge. It sits apart from the brain around it rather than growing into it. It is the opposite of diffuse. That is why some of these can be cured by an operation. See the glossary. That difference matters a lot for surgery.
• Ependymoma, which starts in the cells lining the fluid spaces of the brain and spine.

One thing here catches almost everybody out. You may see the words "adult-type" or "pediatric-type" on a report. Those describe the tumor's biology, not the age of the person who has it. Adults are sometimes told they have a pediatric-type glioma. Children are sometimes told they have an adult-type one. It is not a mistake on your report. Nobody has filed you in the wrong place.

Words that sound like diagnoses but are not

Some phrases describe a group rather than name a tumor:

• Low-grade glioma and high-grade glioma describe how fast a group of tumors tends to grow. Each covers several real diagnoses.
• Diffuse glioma means the tumor spreads out into the brain around it rather than sitting in one lump.

You can be told any of these and still not have been told your diagnosis. It is completely fair to ask, "so what is the full name of mine?"

Is it cancer? What does its grade mean?

Some gliomas are cancer and some are not, and which one you have is the thing that decides it. That is not a dodge, and this section gives you enough to work out where yours sits.

The word doctors use for the ones that are cancer is malignant. The word for the ones that are not is benign. But benign in the brain does not mean harmless. A benign tumor still takes up room inside a closed skull, and it can still press on a part of the brain that matters. It is a statement about how the cells behave, not a promise that it will not cause trouble.

Grade 1 gliomas sit in a defined lump with a border. Most of them can be cured by surgery, if the surgeon can safely reach all of it. For those, "they got it all" can genuinely mean finished.

Grade 2 and above are different for most gliomas. Most of them grow out into the brain around them, so there is no edge to cut around. They are malignant, and with today's treatments they are not curable. That is a hard sentence and it is here on purpose. Being told "low grade" and hearing "not serious" is the commonest misunderstanding about these tumors. It falls apart later, at the worst possible moment.

Ependymoma is different from the gliomas this paragraph describes, and its page explains how.

Not curable is not the same as untreatable, and it is not a timeline. Treatment can work for a long time. Some of these tumors are watched rather than treated for years. What it means is that the plan assumes the tumor will need attention again, which is why the scans do not stop.

What the grade actually describes

A grade describes how normal or abnormal the tumor cells look under a microscope. In a lower grade tumor such as grade 1, the cells look close to normal. In a higher grade tumor such as grade 4, they look more abnormal.

Two things about grade trip people up.

Grade is not the same across different tumors. Since 2021, grading is done within each tumor type. A grade 4 of one tumor type does not mean the same thing as a grade 4 of another. So comparing your grade with somebody else's, when you have different diagnoses, does not tell you what it seems to.

Grade is no longer only about how the cells look. Gene results can now set the grade. That means a tumor can be given a higher grade than its appearance alone would suggest. The words on your gene results explains the individual tests.

Why does my report have a grade but no stage?

Most cancers are given a stage, which describes how far they have spread through the body. Brain tumors are given a grade instead.

The reason is biological. A glioma can spread within the brain, but it very rarely leaves the central nervous system for the rest of the body. Cases have been reported, but they are unusual enough to be written up when they happen. So the thing staging is designed to measure mostly does not apply here.

Where does it grow, and why does it cause these symptoms?

Most people are told what they have long before anyone explains what it is doing. These are the ways a tumor in the brain causes symptoms. They overlap, and most people have more than one going on at once. Which of them apply to you depends on what your tumor is and where it sits.

It takes up room. The skull is a closed box. It cannot stretch. So anything new inside it has to push on something. The tumor and any swelling around it together take up space and press on nearby parts of the brain.

It can make the brain around it swell. This one surprises people, and it is worth understanding. Fluid builds up in the brain tissue near the tumor. That swelling plays a major part in deciding what symptoms you get. Some of what you are feeling may not be the tumor itself. It may be the swelling around it. That is why medicines that bring swelling down can change how somebody feels, without the tumor being any different than it was.

Pressure can build up inside the head. When the pressure inside the skull rises, there is a pattern doctors watch for: headaches that are worse in the morning, feeling sick to your stomach and throwing up, odd eye movements, seizures, and being confused or very drowsy. Not everybody with raised pressure has all of it, and some people have almost none of it. If this pattern is new for you, it is worth a phone call rather than a wait. If you have a shunt, it means getting help right away.

It can set off seizures. A tumor and the irritated brain around it can upset the normal electrical activity of that part of the brain. For some people a seizure is the first sign that anything is wrong.

It can block the flow of fluid. The brain makes a fluid that circulates around it and drains away. A tumor sitting in the wrong place can block that flow, so the fluid backs up and the pressure goes up. This is more likely with tumors near the narrow channels the fluid passes through. It can be treated, and the usual treatment is a shunt. That is a thin tube that carries the fluid to another part of the body, where it is absorbed. It is the word your team will use. Shunts and hydrocephalus covers what having one is like, and the signs it has stopped working.

Why your symptoms are the ones you have

The short rule: the symptom tells you where, the scan tells you what. A tumor disturbs whatever job the brain does in that spot, so where it sits decides what you notice.

There is one exception, and it is the fluid. When the flow is blocked, what you notice is the pressure rather than the spot: headaches worse in the morning, throwing up, double vision, and feeling unsteady. Those signs are much the same wherever the blockage sits, so they tell you the pressure is up, not where the tumor is. If that is your pattern, the part above called It can block the flow of fluid is the one about you, and it says what can be done. If the pattern is new, the phone call above applies.

• Front of the brain. Personality, behavior, planning, motivation, and on one side, producing speech.
• Side of the brain, near the temple. Seizures, memory, and understanding what people say.
• Upper back part of the brain. Sensation, knowing where your body is in space, reading, writing and arithmetic.
• Back of the brain. Vision, and losing part of your field of view.
• Cerebellum, low at the back. Balance, coordination and walking.
• Brainstem. Double vision, facial weakness, and trouble swallowing.
• Deep in the middle, near the spaces the fluid runs through. A tumor here can block the flow, so what you notice is often the pressure rising rather than anything that points to the spot.
• The floor of the skull, below and behind the ear. Hearing, balance, and the nerves to the face. So hearing loss or ringing in one ear, dizziness, and numbness or weakness down one side of the face. Your team may call the whole floor of the skull the skull base. This spot is one part of it.
• Behind the eyes, at the base of the brain. Vision, and the hormones that set energy, weight, thirst and periods. In a child, growth and puberty too. Side vision is what usually goes first, so things start disappearing at the edge. Your team may call this the pituitary or the sellar region.

If something on this list matches what you have noticed, it is worth writing down and taking to your next appointment. Your team can tell you whether it fits where your tumor actually is.

This list is about what the place explains. The other half of the question is what the place changes: whether an operation is offered, how much of it can come out, and when the place makes something urgent on its own. Where your tumor is, and what that changes is that half.

The one that is specific to gliomas

Most gliomas do something the list above does not cover: they grow through brain tissue instead of pushing it aside. They do not sit in a neat ball with an edge. Tumor cells spread out into the normal brain around them, and they reach further than the abnormal area you can see on a scan. So a scan understates how far the tumor really goes.

This is the reason "they got it all" and "cured" are not the same sentence for most gliomas. It is not that your surgeon missed something. It is that the edge that shows on the scan is not the true edge.

Not every glioma behaves this way. A smaller group of them sit in a more defined lump with a clearer border, and for those, surgery can mean something closer to finished. Which kind you have is on your pathology report, and it is one of the most useful things to ask about.

Seizures are one of the most common ways a glioma first shows up, along with headaches, feeling sick to your stomach, and problems with movement, speech or sensation. And for tumors at the front of the brain, changes in behavior and personality can be present for months or even years before anybody thinks of a scan. That is why some people look back and recognize something they could not name at the time.

Some people have no symptoms at all. A small share of lower-grade gliomas are found by accident, on a scan done for something else entirely. If that was you, the strangeness of being told you have a brain tumor while feeling perfectly well is real. Say so to your team rather than assuming you have no right to be shaken by it.

What symptoms does it cause?

The most common ones are headaches, seizures, feeling sick to your stomach or throwing up, and problems with movement, speech, sensation or thinking. Which of them you get depends mostly on where the tumor is, which the section above walks through.

When to call for help right now

Some things should not wait for the next appointment.

Call an ambulance for any of these. Call 911, or your local emergency number:

• A first ever seizure.
• A seizure that lasts more than five minutes.
• One seizure right after another, with no waking up in between.
• Someone who cannot be woken.
• Trouble breathing, or someone who seems to be choking.
• Suddenly not being able to speak, move one side, or see.

A seizure like the ones you usually have, that stops on its own, is not an ambulance call. What to do during a seizure draws the line.

Call your team the same day for any of these:

• A headache much worse than usual, or one that wakes you from sleep.
• Throwing up again and again.
• New weakness in the face, an arm or a leg.
• New trouble speaking, or understanding what people say.
• New confusion.
• Sleeping much more than being awake.
• A sudden change in your vision.

If you are having chemotherapy, a fever is its own rule. It means calling your team right away, at any hour, not waiting for the morning. An infection during chemotherapy can get dangerous fast, and it is treatable when it is caught early. The fever rule explains why, and what number your team will give you.

In the weeks after brain surgery, a fever is its own rule too, especially with a stiff neck or a bad headache. What comes after a craniotomy has the rest of that list.

If you have a shunt, the signs it has stopped working are their own rule. For you, everything on the same-day list above is a right-away call instead, and so are a few other signs. Get help right away, at any hour: call your team, or go to the emergency department. Signs a shunt is not working has the full list.

If you are not sure whether to call, call. Nobody on that team minds a phone call that turns out to be nothing.

Same day means today, not the next clinic appointment. Ask your team now for the after-hours number, and put it somewhere you will find it at two in the morning rather than somewhere sensible.

What to do during a seizure has the step-by-step, and getting help now is the short version to keep on a phone.

How do doctors find out it is this?

Usually a scan comes first, then a tissue sample.

• An MRI scan shows where the tumor is, how big it is, and something about how it is behaving.
• A tissue sample. A scan can suggest a glioma. It cannot give you the exact name. That needs a piece of the tumor, taken either at an operation or by a needle biopsystereotactic biopsy: Taking a small sample through a narrow opening in the skull, guided by a scan. A full opening is not made. It is used when the area to be sampled is hard or risky to reach. See the glossary.
• Gene tests on that tissue. These are what separate the three main adult diagnoses from each other.

How tissue is taken is about that step: the needle, the operation, and what happens if the sample does not give an answer.

The full answer arrives in layers, not all at once, and the name can change as later results come back. Waiting for results is about that wait, which is one of the hardest parts of this whole process.

What do the words on my report mean?

Your report should carry the tumor type, a grade, and the gene results, brought together into one final answer. Doctors call that combined answer the integrated diagnosis, and it is what your team treats.

Your pathology report, part by part walks through the document itself, and the words on your gene results explains each test in turn.

If your paperwork uses words you cannot find

The rules for naming brain tumors changed in 2021. If your paperwork was written before that, some of its words are no longer used.

This matters more than it sounds. People read an old report next to a new one, see two different names, and think somebody made a mistake. Usually nobody did. The tumor did not change. The way doctors write it down changed.

Three changes affect almost every report.

• Roman numeral grades, such as grade II or grade IV on an older report. These are now written with ordinary numbers instead: grade 2, grade 4. Nothing about the grade itself changed. Only the way of writing it did.
• Gene results are now part of the name. Older reports named a tumor mostly by how the cells looked. A name written now usually has a gene result built into it. That is why a newer report can look longer and more technical than an older one about the same tumor. You may also see NOSNOS: Short for "not otherwise specified". It means the gene tests needed to name the tumor fully were not done or could not be done. Ask your team whether they can be. See the glossary or NECNEC: Short for "not elsewhere classified". The tests were done, but the results do not match any named tumor type. Ask your team what it means for your plan. See the glossary written next to your diagnosis. These say something about the testing, not about how serious the tumor is. NOS means the tests needed to be more exact were not available. NEC means testing was done, but the results did not fit any defined group neatly.

Seeing an older name on your own report does not mean it was wrong. It means it was written under the old rules. If you are holding an old report and a new one and they do not match, that is a good thing to take to your team and ask about.

The glioma names that changed

These are the ones most likely to be on an older report about a glioma.

• Anaplastic anything, such as anaplastic astrocytoma. Doctors no longer use the word anaplastic when they name these tumors. The grade does that job now. You will still hear people say it.
• Diffuse astrocytoma, on its own. This is no longer a diagnosis by itself. It is now written with the gene result and a grade attached. See astrocytoma.
• Oligoastrocytoma, sometimes called a mixed glioma. This one no longer exists at all. It used to be the name for a tumor that looked like a mix of two types. Gene tests can now sort those tumors into one group or the other, so the mixed name was dropped.
• Secondary glioblastomaglioblastoma: A glioma that is given grade 4. Grade 4 is the highest grade there is. The tumor grows fast. Treatment usually starts soon after it is found. It often means surgery, and then radiation and chemotherapy. See the glossary, or glioblastoma with an IDHIDH gene change: A small change in a tumor's IDH gene. It is the first thing your team looks at when naming an adult glioma, and it can affect which treatments are offered. Your pathology report says whether your tumor has it. See the glossary change. Now called astrocytoma, IDH-mutant, grade 4, so the page you want is astrocytoma, not glioblastoma. These tumors were found to behave differently from the ones still called glioblastoma, so they were moved out from under that name.
• Glioblastoma multiforme, or GBM. Now just glioblastoma, IDH-wildtype. Many people still say GBM in conversation.
• DIPG, or diffuse intrinsic pontine glioma. That name described where the tumor sat. Most of these are now called diffuse midline glioma, H3 K27-alteredH3 K27-altered: A change in a histone. A histone is a protein DNA wraps around. A diffuse glioma can have it. If it also sits in the middle of the brain or spine, it is called a diffuse midline glioma. See the glossary.

Two things follow from all this, and both surprise people.

A tumor with an IDH change is never called glioblastoma now. If your 2016 report said secondary glioblastoma and your new one says astrocytoma, you have not been given a different disease. It was renamed.

It also runs the other way. A tumor can now be called grade 4 because of its gene results, even when the cells did not look that way under the microscope. So you can be told grade 4 when nobody saw the changes that used to be required for it. That is the new rules working, not a mix-up.

How is it usually treated?

Treatment is chosen from the exact type, the grade and the gene results together. This is the practical reason all that naming matters: the classification is what guides the treatment. Two people who both say they have a glioma can be offered completely different plans, and neither is wrong.

The usual building blocks:

• Surgery, to take out as much as can safely be taken and to get tissue for testing. If the tumor is close to the parts that handle speech or movement, you may be awake for part of it. Awake brain surgery explains why.
• Radiation therapy, often after surgery.
• Chemotherapy, as pills or into a vein, depending on the drug.

Which of these apply, in what order, and whether any apply at all depends entirely on which glioma you have. Some people are watched rather than treated at first, and that is a plan rather than an absence of one. Watching a tumor, step by step goes through what that involves.

Alongside all this there is supportive treatment. That means medicines to stop seizures, medicines to bring swelling down, and treatment for a fluid blockage if you have one.

A tumor board is a meeting where specialists look at one person's case together: surgeons, cancer doctors, the lab, and the people who read scans. It tends to happen when a case is complicated or something is hard to read.

You do not go to the meeting. Afterwards, the doctor who knows you best explains what was said.

What they decide is advice, not an order. The choice is still yours. Because you are not in the room, tell your team what matters to you before it happens, so it is taken into account.

What is treatment actually like, and what is normal afterwards?

The part people are least prepared for is that finishing treatment is not the same as feeling finished. Tiredness after radiation often arrives late and lingers. Thinking and memory can feel slower for a while. Both of these are common and neither means treatment failed.

If you are about to start something and want to know what the day itself involves, these are the pages that walk through it: surgery, radiation therapy and chemotherapy. Each one covers what is normal afterwards and when to call somebody.

Everyday life: work, driving, seizures and tiredness

Seizures and driving. If you have had a seizure, or are at risk of one, living with seizures covers the practical side: water and bathrooms, cooking, sleep, alcohol, and how to keep doing the things you want to keep doing. The rules about driving vary a lot by where you live. In some places it is your doctor who has to report it, not you. Start with the driving section, then confirm it with your own team.

Work and money. Many people keep working, sometimes with adjustments. Some need time away and then return. The financial side is one of the most stressful parts and it is worth asking early what help exists.

Tiredness and thinking. Tiredness is one of the most common and most underestimated effects, and it is not the same as ordinary tiredness. Alongside it, many people notice their memory or concentration is not what it was. Both are worth saying out loud to your team rather than pushing through, because there are things that help and nobody offers them if they do not know.

Follow-up scans, and what to do while you wait

Most people with a glioma stay on long-term scan follow-up, often for years. The scans are how a change gets spotted early, while there are still choices about what to do.

The waiting is its own problem, and it has a name: scanxiety. Patients coined it, and it is worth knowing because it is the word that will find you other people who get it.

For most people the worst part is not the scan. It is the gap between the scan and the result. Knowing that in advance helps, because it tells you which days to plan something for. Tell your team if that wait is hard. Sometimes the timing can be changed, and sometimes saying it out loud is what helps.

If something changes between appointments, you do not have to wait for the next one. Bringing a scan forward is an ordinary thing to ask for.

Follow-up scans, and what the results mean goes through the rest of it: what your team compares your scan with, what the words on the report mean, and why a scan that looks worse is not always worse.

If it comes back, or changes

For many gliomas, a change over time is expected rather than surprising, and your team will have been watching for it from the start. That is what the scans are for.

If something does change, there are usually still options:

• More surgery.
• Radiation, if it has not been used yet or can be used again.
• A different drug.
• A clinical trial, which is worth asking about earlier than most people do.

Which of these are open to you depends on your diagnosis, what you have already had, and how you are doing in yourself.

Being told there has been a change is a hard day. It is not the same as being told there is nothing left to try.

Did I cause this?

Almost everybody asks this, usually in the first week, usually in private. It is worth answering plainly.

For most brain tumors, nobody knows the cause. That is the honest state of it. The exact cause of most brain and spinal cord tumors is not fully understood, and there are very few well established risk factors. Tumors start when genes that control how cells grow and divide are changed, and in most cases those changes happen by chance during a person's life. Not because of something done or not done.

Cell phones. They give off a kind of radiation called radiofrequency. It is not the same as the radiation in an x-ray. The energy is too low to damage DNA, and it is not known to cause cancer. The evidence so far is that using a cell phone does not cause brain tumors.

Stress. There is no scientific evidence that stress causes brain tumors, and no data linking stress to a higher chance of getting one. A hard year before a diagnosis is a hard year. It is not a cause.

Something you ate, or did not eat. No food and no diet is an established cause of a brain tumor. It is not on the list of known risk factors at all.

Something you passed on, or caught. Brain tumors are not contagious. Most are not inherited either. A small number of people do have an inherited condition that raises the risk, and if that applies to you, your team will raise it and offer to talk it through.

If you are turning this over at three in the morning, that is ordinary and it happens to nearly everyone. It is also worth saying out loud to somebody on your team, because they have answered it many times and they would rather you asked.

What might happen over time

For the person caring for someone with this

If you are the one driving to the appointments, keeping track of the pills, and lying awake at night worrying about them, this part is for you.

You are allowed to ask questions. In one study, families said they were afraid of annoying the doctor by asking too much. One of them was told by a doctor to stop playing doctor. Ask anyway. Write your questions down before you go, and bring a notepad. Two people in the room hear more than one.

Ask who your first call is. Care comes from a lot of people at once, and it is easy to end up as the only one holding it together. Ask the team: who do I call first? Some teams have one person whose job this is, often a nurse. Get the name and the number.

Get two numbers, and know which one to use. One for work hours, one for nights and weekends. Then ask what counts as "call us today" and what counts as "call an ambulance" for this tumor, and write the answer down where you can see it. If you are not sure which it is, call. Nobody on that team will mind.

If they have seizures, read about them before you need to. What to do when someone has a seizure is the one to know by heart. Living with seizures is about the rest of the time: what is safe, what to change, and driving.

Ask to be shown anything you are sent home to do. In that same study, families were sent home to change dressings and give medicines with no training at all. That is not fair to you. Before you leave the hospital, ask someone to show you. Then do it once while they watch.

Say what you notice. You may see a change before they do. Changes in thinking, mood and behavior can show up to the people close by first. Telling the team is not going behind their back. It is something the team cannot learn any other way.

Look after yourself, and let people help. Eat, sleep, and keep your own appointments. Take a little of the day back for yourself. When someone asks what they can do, give them a real job: a meal, a ride, an hour with the kids. Most people want to help and do not know how to offer.

You can talk to somebody about all of this today. See where to get help.

Which glioma it is changes what this job looks like. For a grade 1 that was fully removed, the work may be a few weeks of recovery and then scans. For a diffuse glioma it is a longer road, with stretches where nothing much happens and stretches where a lot does. It is fair to ask the team which of those you are looking at, and you are allowed to ask it without the person you care for in the room.

If seizures are part of this, they are the thing most caregivers most want to be ready for. What to do during a seizure is the step-by-step, worth reading before you need it, and living with seizures covers the rest of the time.

What to ask your team

• What is the full name of my tumor, including the grade and the gene results?
• Is that name on my pathology report, and can I have a copy?
• My older paperwork uses a different word. Which one applies now?
• Which parts of my treatment are decided by the gene results?
• Is any of what I am feeling caused by swelling rather than the tumor itself?
• What would make you want to see me before my next appointment?
• Who do I call after hours, and what number is it?
• Is there a clinical trial I should know about?

Where to get support

• Getting help now if you need somebody today.
• Living with seizures for the practical side of seizures.
• Your team's specialist nurse, who is usually the fastest way to get a question answered without waiting for a clinic appointment.
• Other people with the same diagnosis. Many people say this helped more than they expected, once they found the group that matched their actual tumor rather than brain tumors in general.