Craniopharyngioma

A growth that sits next to the pituitary gland, the nerves for sight, and the space the brain's fluid drains through. Why sight, hormones and fluid are the three things a team watches. What the two type names on your report mean. And the warning signs this page carries rules for.

The short version

A craniopharyngioma is a growth that sits deep in the head, just above the gland that runs your hormones. It is slow growing, and it is not cancer.

It causes trouble because of where it is, not because it spreads. Three things sit right next to it: the nerves for sight, the hormone gland, and the narrow space the fluid around your brain drains through.

So the three things a team watches are your sight, your hormones, and that fluid. Most people need an operation, and many need hormone medicine afterwards, often for good.

Two sets of warning signs here are handled differently, and they are worth knowing before the night you need them. You will find them in the symptoms section.

What is a craniopharyngioma?

It starts from a few cells that were left behind before you were born.

Long before birth, a small tube of tissue helps build the gland under your brain. Nearly all of it disappears. In a few people, some cells stay behind, and many years later a growth can start from them.

That is why nothing you did caused it, and why it can turn up at any age.

It is often part solid and part fluid. Many of these growths have one or more fluid-filled sacs mixed in with the solid part. Doctors call a sac like that a cyst. The cysts matter as much as the solid part, because a sac that fills up takes room just as a solid lump does.

It sits in a small space at the base of the brain, right by the gland your report may call the pituitary. Your team may say it is near the stalk, which is the thin bridge joining that gland to the part of the brain above it.

Is it cancer? What does its grade mean?

No. It is not cancer, and it does not spread around the body.

Your report may use the word benign. The word is accurate, and left on its own it will mislead you, so here is the whole of it.

Benign says the growth is not cancer, and that it will not travel to other organs. It does not say small, and it does not say easy. Surgeons describe these growths as benign but locally pushy: they sit among things you cannot do without and they tend to stick to them. A growth that is not cancer can still take part of your sight, and can still stop a gland working.

Harmless is a different word, and it is not the one that applies here.

If your report carries a grade, it will be the lowest one. Grades run from 1 to 4 and describe how a growth is expected to behave. This one is a grade 1. On an older report the very same thing is written as grade I.

What matters is what it presses on, and how your hormones are doing. Both of those come further down.

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

Almost everything on this page follows from its three neighbours.

It grows in a small hollow near the base of the brain. Above it run the nerves carrying sight from each eye, crossing at a spot doctors call the chiasm. Below it sits the hormone gland. Behind and above lies a narrow channel that the fluid around your brain passes through, and the part of the brain that controls hunger, sleep, temperature and thirst.

So trouble from this one arrives in three different ways.

It can press on the nerves for sight. Because of where those nerves cross, what fades first is usually the outer edge of vision on each side. People often do not notice it early. It gets found on a proper eye test, or when somebody keeps bumping into things they did not see coming.

It can stop the gland working. Then you make too little of one hormone or several. In a child that often shows up as growth slowing down or puberty arriving late. At any age it can show up as tiredness, feeling cold, or a thirst that will not settle.

It can block the fluid. This is the one that can come on fastest, and it is why the symptoms section carries a rule for it.

A note on what follows. The part below is written about brain tumors in general. The piece that matters most here is the fluid. In the brain map that follows, the entry to read is the one about behind the eyes, where the pituitary sits. The deep middle entry can apply too, because of the fluid. The rest of the map is about growths elsewhere. That general part also carries advice to make a phone call rather than wait when pressure signs are new. Here that is overridden for these signs: the rule in the symptoms section is stronger, and it is the one to follow.

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.

What symptoms does it cause?

They fall into the three groups above: sight, hormones, and fluid.

From pressure on the nerves for sight, the common ones are losing the outer edges of your vision on both sides, blurred sight, and sometimes double vision.

When hormones run low, the signs are broad and easily explained away: tiredness, weakness, dizziness, weight that shifts, feeling cold all the time, dry skin, changes to your periods, and less interest in sex. In a child, slow growth or late puberty is often what gets noticed first. Nothing on that list points at your head.

A thirst you cannot satisfy, with far more trips to the bathroom, is its own thing, and it is common here. It happens when the back of the gland can no longer hold water in the body. An older name for it borrowed the word diabetes. What most people mean by that word is a completely different illness.

From the fluid backing up, the signs are headaches, throwing up or feeling sick to your stomach, being much sleepier than usual, and being confused. Headaches from this are often worse in the morning.

Two sets of signs here carry rules of their own. Both sit just below these lists.

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.

This tumor has two rules the list above does not carry. Both are better learned now than looked up in a hurry.

If these signs arrive quickly, or arrive together, treat them as urgent. A headache that is getting worse, throwing up again and again, being much sleepier than usual, being confused, or your sight changing quickly. Those same signs appear on the same-day list above, and they are the ones this growth has a reason to cause, because it sits right where the fluid drains, and a blocked drain can need treating quickly. These need help right away, at any hour, not a wait for the same day. Phone your team whatever the hour, or head for the emergency department. If someone cannot be woken, if speech or one side suddenly stops working, if sight suddenly goes, or if a first seizure happens, call 911, or your local emergency number, without waiting to reach anybody else. This is treated, and treating it early is the whole point. Shunts and hydrocephalus has the full list of signs for anyone who already has a tube draining that fluid. This rule is yours even if you do not have one of those tubes.

Rarely, one of these growths bleeds inside itself, and that brings the same signs on suddenly. It is uncommon enough that it is not what a headache usually means. It is in this list because the answer is the same either way: get seen.

If you take a steroid as replacement, being ill changes the rules. A body that cannot make its own stress hormone has no reserve to draw on, so an everyday illness can turn serious. An infection, an operation or an injury does the same. Doctors call it an adrenal crisis, and the Endocrine Society says it can kill if it is not treated.

Watch for being very sick to your stomach, confusion, feeling faint, and sudden weakness. If that is happening now, do not wait: call 911, or your local emergency number. A hospital is where this gets treated. If you carry an emergency injection, this is the moment it is for, and you go in afterwards anyway. Ask your team now for a written plan of your own: what to do on days when you are ill, what to do when medicine will not stay down, whether an emergency injection belongs in your bag, and whether to wear medical alert jewelry. Steroids goes into the medicine itself, and sets out the identical rule for anyone whose body has stopped making its own.

This can be yours before anyone has put you on replacement. For some people a crisis is how the problem gets found at all. If this growth, or an operation on it, has harmed the gland, take these signs just as seriously.

Both rules are worth explaining to whoever you live with.

How do doctors find out it is this?

A scan, blood tests, a proper eye test, and in the end the tissue itself.

An MRI scan shows where the growth sits and what it is touching. A CT scan is sometimes added, because the specks of calcium these growths often contain show up well on it, and that helps tell this apart from other things that grow in the same spot.

Blood tests show which hormones are low, and that shapes what happens next.

When the growth sits close to those nerves, a proper eye test is arranged. It is not the sight test you have for glasses. It charts the edges of your vision, which is where loss begins here, and repeating it later is how small changes get noticed.

The scan usually points to it, and the blood tests show what the gland is doing. But the diagnosis and the type name are confirmed on tissue taken during the operation, and that is one of the reasons an operation comes first.

What do the words on my report mean?

Your report may carry a long type name, and it is a description rather than bad news.

Adamantinomatous, and papillary. These are the two kinds. The first is the one seen most often in children, and it usually holds cysts and specks of calcium. The second is seen almost only in adults. They look different under a microscope and they carry different gene changes.

Until recently they were treated as two versions of one growth. The World Health Organization now counts them as two separate types, because they turned out to differ in who gets them, how they look on scans, and what is going on in their genes. So a newer report may name yours more precisely than an older one would have. Nothing about your growth changed.

A gene name may appear too. One of these types usually carries a change in a gene called BRAFBRAF: A gene in a pathway that tells cells to divide. Some tumors carry a change in it. There are drugs made to target that change, so your team may test for it. See the glossary. That is not part of the growth's name, and it is not something you inherited or passed on. What it changes is the treatment, which is why the treatment section returns to it.

Grade 1, and grade I on an older report. Both mean the same thing. The rules for writing grades changed in 2021, from Roman numerals to ordinary ones, and plenty of paperwork still carries the earlier style.

Diabetes insipidus, and arginine vasopressin deficiency. These are two names for the same thing: the trouble with thirst and peeing a lot described above. The name was changed on purpose, because sharing the word "diabetes" with a completely different illness was getting people hurt. Pituitary tumor tells that story in full, and a report saying both names at once is doing exactly what was intended.

Your pathology report goes through the document itself, though yours may not carry everything that page describes.

How is it usually treated?

An operation is almost always the first step, and what is aimed for has changed.

Surgery. The goal is to take pressure off the nerves for sight and to unblock the fluid, and to find out exactly what the growth is. There are two routes in, and which one is used depends on where the growth sits and how far it reaches. One goes up through the nose and the sinus behind it. The other is through an opening made in the skull. What comes after an operation covers the general aftercare.

How much is taken out is a real decision, and it is worth asking about. Taking out every last piece lowers the chance of it coming back. But these growths stick to things you cannot do without, and pulling tissue away from the part of the brain that controls hunger, sleep and temperature can cause lasting problems of its own. Many teams now deliberately leave a piece alone rather than risk that, and treat what is left another way. Surgeons are also advised to spare the stalk where they can. There is no single right answer, and it depends on your own scan.

Radiation, often after surgery, treats what was deliberately left behind or what has come back. Radiation therapy covers the course itself and what to ask about afterwards.

Draining a cyst. When the growth is mostly a fluid sac, a thin tube can be put into it to let the fluid out. Sometimes a small reservoir is left under the scalp so the sac can be drained again without another operation.

Medicine aimed at a gene change. For the adult type that carries the BRAF change, drugs aimed at that change can shrink the growth. Where the type is already known, they are sometimes given first, to make the operation easier. This is newer than the other options. The reports so far are small, side effects are common enough that some people stop, and how long the benefit lasts is not yet settled. It is a fair thing to ask whether your type carries that change.

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

Hormones afterwards

Many people need hormone medicine afterwards, and often for good. That is not a sign that something went wrong. It is an expected outcome of treating a growth in this spot, and the missing hormones can be replaced.

Which ones you need depends on what the growth and the treatment affected. A hormone doctor takes this over and stays involved for the long term.

If one of them is a steroid, go back and read the illness rule above, and make sure your plan is written down before you go home. Tell any doctor treating you that you take it, especially before an operation or if you become ill.

Say so if thirst becomes constant and you are passing far more water than before. It is common after an operation in this spot. It is treatable, and it is much better said than worked out at home.

Sight often gets better once the pressure comes off, and it will be tested again after the operation. How much comes back depends partly on how long the nerves were under pressure.

When hunger and weight change, and it is not willpower

This one deserves its own explanation, because it is the part most often misunderstood by everyone around you.

The area next to this growth controls hunger and how much energy your body burns. If it is damaged, by the growth or by treating it, hunger can become very hard to control and weight can climb fast.

This is not a lack of effort, and saying so is not kindness, it is the finding. Weight gain from damage in that spot mostly does not respond to ordinary advice about eating less and moving more. The same damage can also upset sleep, body temperature and mood.

Teams do take it seriously, and there are things to try. It is honest to say that results so far have been disappointing, and that no drug for it has yet been proven to work in the strongest kind of trial. Ask who on your team looks after this, and ask early rather than after a year of being told to try harder.

Everyday life

From day to day, this comes down to hormones, sight, and how much energy you have.

If you take hormone replacement, it needs a daily routine, and a separate plan for the days you are sick. That written plan is the thing to keep where you can find it in a hurry.

If your vision has altered, get it tested before you go back to driving. The sight you lose first is exactly the sight you lean on at the edges of the road.

When what changed is your sight takes the rest of that: what a field test shows, who decides about driving, and who can help you work out whether you still can.

Tiredness, sleep that is out of step, and trouble holding attention are all common here, and they are worth saying out loud at appointments rather than absorbing at home.

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

Follow-up here is scans, blood tests and eye tests together, and it goes on for a long time.

Follow-up scans covers how each new scan is compared with the one before. Waiting for results is for the wait itself.

Have your own schedule written down, and know what would bring a scan forward.

If it comes back

These growths come back often enough that follow-up is built around it.

It usually comes back in the same place. The choices are the same as before: another operation, radiation, draining a cyst, or in some cases medicine aimed at a gene change. Which of them fits depends on the first round of treatment and on what remains.

Coming back is not only an early risk. It usually happens in the first few years, but it has been reported many years later, which is why check-ups carry on long after you feel finished with all this. If you have been told follow-up goes on indefinitely, that is why.

Ask what each option is meant to achieve, and write it down while you are being told.

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.

For this growth there is a more definite answer than usual. It starts from cells left behind before you were born, so there was nothing to prevent and nothing to avoid. If you are a parent combing back through the pregnancy for a mistake, there is no mistake waiting to be found.

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.

Three things are specific to this one.

Learn both urgent rules alongside them. One is signs that arrive quickly or together; the other is illness in anyone whose gland has been harmed, whether or not they are on a replacement steroid. You may well spot either before they do, and neither can wait until morning.

Hunger and weight changes are not a lack of effort. If the area that controls appetite was affected, hunger can be very hard to control, and ordinary advice about eating less does not work. Treating it as willpower is the most common way this goes wrong at home.

A failing gland can look like a change of character. Being tired, flat, cold or uninterested can all come from hormones that have stopped arriving, rather than from someone who has stopped trying. Say it to the team rather than keeping it to yourself.

What to ask your team

• Which hormones are low now, and which will be checked later?
• Has my sight been mapped properly, and when will it be done again?
• Is the fluid draining normally on my scan?
• What is the plan: an operation, radiation, draining a cyst, or a mix?
• How much are you aiming to take out, and what are you deliberately leaving?
• Which type is mine, and does it carry the gene change that has a medicine?
• Will I need hormone replacement, and for how long?
• If I need a steroid, what is my plan for days when I am ill?
• Should I carry an emergency injection and wear medical alert jewelry?
• Who looks after appetite and weight if that becomes a problem?
• What would make you want me to call before the next appointment?
• Who do I call after hours, and what is the number?

Where to get support

• Getting help now, for the day a page is not enough and you need a person.
• When your child has a brain tumor, if the person with this is your child. It covers what changes when the patient is a child, from holding still for a scan to school and the long tail of check-ups.
• The Pituitary Network Association publishes patient material on growths in this part of the head and the hormone problems they cause.
• The specialist nurse on your team, who is usually the quickest way to a real answer.