Stereotactic radiosurgery: it is not surgery, and it is usually one day

Gamma Knife and CyberKnife sound like operations and are not. Nothing is cut and you stay awake. What the day is really like, including the long wait while your plan is built. And why success is often a tumor that simply stays the same size.

The short version

Nothing is cut. Stereotactic radiosurgery is radiation, not an operation, and the name is the most misleading thing about it. A lot of faint beams are aimed at your head from different angles, and they cross at one small spot. Only where they cross is the dose large enough to matter. You are awake the whole time and you feel nothing while it runs. It is usually one day rather than weeks of visits, and you usually go home the same evening. The longest part of the day is the wait while your plan is built, and this page spends time on it because most others do not.

What is it?

It is a way of giving a large dose of radiation to one small target in a single visit, or in a small number of visits.

Each beam on its own is weak. On its own it would do very little to anything it passes through. The beams come in from many different directions and cross at the tumor, and only where they cross is the dose large. That is how the tissue around the target is spared.

There is no knife and no cutting. The American Cancer Society says it plainly, and so does Cleveland Clinic: despite the name, this is not surgery. There is no incision, no general anesthetic, and nothing is taken out. The name is about how exactly the beams can be aimed. Cleveland Clinic puts it as being as accurate as a surgical knife, without cutting into your body. That is where the word comes from, and it is a poor word for what happens to you.

You will hear machine names, and they are doing the same job. A Gamma Knife aims a couple of hundred thin beams at the target from fixed positions, all at once. A CyberKnife, or a linear acceleratorlinear accelerator: The machine that gives external radiation. It moves around you and aims the beam. Like an x-ray, the radiation from it is painless. See the glossary set up for this, uses one beam and moves around your head to come at the target from many angles. Which one your center has is a fact about your center.

Two sets of initials turn up on letters. SRS means the whole dose in one visit. SRT, sometimes written as fractionated radiosurgery, means the same idea split over a few visits. If your letter says one of these, that is what it is telling you. Ask how many visits yours is, and why that number. It depends on what is being treated and where it sits.

Why this and not an operation, or weeks of radiation?

Because of what it can reach, and what it can be aimed at.

It suits a small target with an edge that can be drawn, and it takes nothing out, so there is no tissue for the laboratory. The team has to be able to say exactly where the treated area stops, and nothing comes back from it that a pathologist can look at, so it does not answer a question about what the tumor is. The size of what is being treated is one of the things that decides whether this is an option at all, so ask where yours falls.

It can reach places an operation cannot. It is used for tumors in parts of the brain that cannot safely be operated on, and for people who are not well enough for an operation.

If cancer has spread to your brain from somewhere else, guidelines from three American cancer societies say this treatment on its own should be offered when there are up to four spots that have not been operated on, with one exception for small cell cancer. They also say it should be offered to the place a spot was removed from, after an operation for one or two of them, when that area can be treated safely. If that is your situation, those are two sentences worth taking to your appointment. Cancer that has spread to the brain is the page for the rest of it.

If you have a 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, the answer is more careful. European guidelines say that for a newly diagnosed 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 this has not been shown to do better than an ordinary course of radiation. For a tumor that has come back, it is one of the treatments considered. So it is a reasonable question at a recurrence and a less likely answer at the start.

It is also used after an operation, on what is left behind or on a spot that has come back.

Ask what it is meant to achieve. Stopping growth, shrinking, or easing a symptom are three different goals, and they change what counts as this working.

What happens, step by step

One day, start to finish, for most people.

1. You arrive in the morning. You will usually have been asked not to eat or drink after midnight, but ask, because centers differ.
2. A line goes into a vein in your arm. It is used for the dye that makes the scan clearer, and it can give you something to help you relax if you want it.
3. Your head is fixed in place, with either a frame or a mask. That step has its own section below.
4. You have a scan with the frame or mask on, usually an MRI, sometimes a CT as well. This takes around half an hour. Its whole job is to say exactly where the target is, right now, in the position you are in.
5. You wait while your plan is built. A neurosurgeon, a radiation oncologistradiation oncologist: The doctor in charge of radiation treatment. They decide which area is treated, and how the treatment is split up. See the glossary and a physicist work out the angles and the dose from that scan. This is the long part.
6. The treatment. You lie on the treatment table, your head is held in position, and the machine does the rest. You stay awake. You can talk to the team, and they can see and hear you.
7. The frame or mask comes off, and you go home, usually the same day.

How long does it take?

Longer than people expect, and almost none of it is the treatment.

• The treatment itself: somewhere between about a quarter of an hour and a couple of hours. It depends on the size and shape of what is being treated and where it sits.
• The planning wait: up to an hour at one large hospital, one to two hours at another. Ask yours.
• The whole day: plan for several hours at the center. One hospital tells people to allow up to twelve hours.

So plan the day, not the treatment. Nobody should be sitting in a parking lot wondering what has gone wrong at hour five. Ask your center what a typical day runs to, and tell whoever is with you.

What does it feel like?

The treatment itself feels like nothing at all. The parts around it are where the sensation is.

The frame, if you have one, is the part people ask about. Four spots are numbed with an injection: each side of your forehead, and the back of your head. Then the pins are tightened. People describe pressure rather than pain. The frame itself weighs less than two pounds, and your head is not shaved for it.

A mask, if you have one instead, is the same mesh mask used for ordinary radiation. What the mask is like, and what to ask for if it frightens you covers that in full, and every word of it applies here.

During the treatment you feel nothing. There is no heat. There is no noise. You do not see the beam. People often doze off, and that is fine.

You are awake and you can speak. You are not put to sleep, and you are not alone in the sense that matters: the team is just outside, watching and listening, and you can talk to them.

You can ask for something to help you relax. You do not have to be in distress to ask, and plenty of people do. Ask at the appointment before the day, not on the morning.

The wait, and what to do with it

This is the part of the day that gets explained the least, so here it is in full.

After your scan, you sit and wait while the team builds your plan from it. At one hospital that is a neurosurgeon, a radiation oncologist and a physicist. You are usually still wearing the frame or the mask holder while they do. It can run to a couple of hours. Nothing is wrong. This is the step that makes the rest of it accurate, and it cannot be done in advance because it is built from the scan you just had.

Things that make it easier, and that centers are used to being asked for:

• Ask in advance how long the wait usually runs at your center. The answer varies by hospital and by how complicated the plan is, and knowing the number is most of it.
• Ask whether the person with you can sit with you. It is worth asking rather than assuming either answer.
• Bring something to listen to, and something to drink if you are allowed it. Reading with a frame on is harder than people expect.
• Ask for something to take the edge off if the waiting is the part you are dreading. It is the same medicine as above.
• Ask what you can do about the feel of it. Pressure from the frame, or a dry mouth, or needing the bathroom are all ordinary things to raise, and none of them is a silly thing to ask about.

You are not being left. It is a fair thing to ask somebody to come and tell you where the plan is up to.

Side effects, in the days after

What turns up in the first few days tends to be mild. Here is the list your center will go through with you.

• Headache, and feeling tired.
• Feeling sick to your stomach, or throwing up.
• Sore pin sites, if you had a frame. There may be a little bleeding when the pins come out, a dressing goes on, and there can be bruising, a change in skin color, and numbness or tingling in the scalp there.
• Grogginess on the way home, from the relaxing medicine. This is why somebody else drives.

One hospital tells people they should be able to get back to work or school the next day, and may be asked to go easy on anything strenuous for a few days. Ask what yours says, because that is a permission rather than a prediction.

Looking after pin sites, if you had a frame. One hospital's instructions are to take the dressing off the day after, clean the sites twice a day with a little antibiotic ointment for three or four days, keep your head up on a couple of pillows for the first week, and leave washing your hair for two days. Your center will give you their own version. Follow theirs, and ask for it in writing before you leave. Pin sites also have their own rule about when to call, and it is at the bottom of the next section, under the list of things that cannot wait.

Side effects that can come later

Two things can turn up well after the day, and both have answers.

Swelling at the treated spot. The area can swell, either soon afterward or months later. It can press on brain around it and bring on symptoms. Steroids often settle it, and your team may give you one around the treatment to head it off. Steroids is the page for that medicine.

A change on a later scan that is not the tumor. Months or years afterward, something can turn up on a scan of the treated spot that looks a great deal like the tumor coming back, and is not. It has a name, radiation necrosisradiation necrosis: Damaged tissue where radiation was aimed, months or years later. On a scan it can look like tumor coming back. Telling the two apart can take more scans, and sometimes a sample. See the glossary, and there is treatment for it. Follow-up scans, and what the results mean explains what it is, how your team tells the two apart, and what the timing usually looks like after this particular treatment. That page owns it. Read it when you get to that scan rather than now.

Hair loss depends on where the target sits. One hospital lists it as happening only when a tumor is close to the scalp. If yours is, ask whether to expect it over that spot.

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.

If you had a frame, the pin sites are this page's own rule. The list above does not have them in it, because no other treatment on this site leaves pin holes in your scalp. Call your team the same day if a pin site turns hot to the touch, if anything cloudy or bad smelling leaks from one, or if you run a fever. The same day, for any one of those three. That is the same answer brain surgery gives for a warm wound, a leaking wound and a fever after an operation.

The fever lines in the list above are written for people having chemotherapy and for the weeks after an operation. Neither of those is you. Yours is the one in this paragraph.

What you need first, or need to bring

Ask your center for their own list, because these vary. In general:

Before the day:

• A recent, detailed MRI with dye. Your MRI scan covers that appointment.
• Tell them about anything implanted. A pacemaker, a cochlear implant, a nerve stimulator, a medicine pump.
• Ask about your blood thinnersblood thinner: A medicine that makes it harder for your blood to clot. Aspirin is one. And there are several others. Never stop one on your own before an operation. Your team decides that. And each medicine is different. See the glossary, if you take any, well before the day. Pins go into your scalp.
• Say if lying flat on your back for half an hour to an hour would be hard, because of your back, your breathing or reflux. Say it early, not on the table.
• Arrange somebody to drive you both ways. Not just home.

The night before and the morning:

• Ask when you have to stop eating and drinking. Do not assume.
• Wash your hair, and leave it loose. No clips, pins, bands or hairpieces on the day.
• Take your morning medicines with sips of water unless you are told otherwise, and bring every medicine you take, including the ones you buy yourself and any inhalers.
• Wear loose clothes and shoes you can slip off. Not a shirt that has to come off over your head, because of the frame.
• Bring something to fill several hours.

For the person taking them

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.

This one is a single long day rather than a course, so what it asks of you is concentrated into it.

You are the ride, and that is not optional. One hospital tells people to arrange a driver both ways, whether they are having a frame or a mask. If they took the relaxing medicine they will be groggy afterward as well.

Clear the whole day. Several hours at the center is normal, and one hospital tells people to allow up to twelve hours. The treatment is the short part. Most of the day is the scan and the wait while the plan is built.

The wait is the hard part, not the treatment. They may be sitting in a frame for a couple of hours with nothing happening. Ask whether you can sit with them. If you cannot, ask somebody to come and tell you both how it is going, because silence in that gap is where the fear grows.

That evening and the day after. They can usually do ordinary things the next day, and are often told to go gently for the first day or two. If there were pins, there is a small dressing and there are pin sites to clean for a few days. Ask to be shown how before you leave, and do it once while somebody watches.

The pin sites are the part no other page on this site covers. Hot to the touch, leaking anything cloudy or bad smelling, or a fever means calling the team the same day. Everything else to watch for is the same list as for any brain tumor, and it is above.

And know that the answer is not coming today. There is nothing to be told that evening. The first real news is a scan weeks or months away. Knowing that in advance stops the drive home being a wait for a phone call that was never going to come.

Why am I having another one?

Being offered this a second time is not automatically bad news.

This treatment can be repeated. Sometimes that is for the same spot. Sometimes it is because a new spot has turned up somewhere else in the brain, which is a different event from the treated one failing, and is one of the reasons you keep having scans.

Your team may also have planned more than one session from the start, if what is being treated is larger or sits somewhere awkward.

Ask which of those it is. "The one we treated has grown", "something new has appeared" and "this was always going to take two" are three different conversations, and people sit through the wrong one for weeks.

Who reads it, and how do I get the result?

There is no result on the day, and it is worth knowing that before you go home.

Nothing is taken out and nothing is sent to a laboratory, so there is nothing to report that evening. The answer comes from a scan some weeks or months later, and then from the ones after that.

Success often looks like nothing happening. The goal is called tumor control, and it means the tumor stays the same size or gets smaller. Both count. A tumor that has stopped growing has done what the treatment asked of it.

That matters because of what the scans show. A tumor that is not cancer often stops growing right away without ever getting smaller. A cancerous one is more likely to become stable or to get smaller over weeks to months. Full effects can take months, and sometimes a year or more.

So "no change" on your report may be the good outcome, and it does not read like one. Ask your team, before you leave, what they will be looking for on the first scan and when it is. Then ask who tells you, and whether the report will appear in your records before anybody calls. Follow-up scans, and what the results mean goes through the words on the report.

What to ask your team

• Will I have a frame or a mask, and why that one?
• How long is the whole day here, start to finish?
• How long does the planning wait usually take, and can somebody sit with me?
• Can I have something to help me relax, and when do I ask for it?
• Is this one session or several?
• What is this meant to do: stop it growing, shrink it, or help a symptom?
• Will I need a steroid afterward, and who adjusts it?
• What should make me call you in the first week?
• When is my first scan afterward, and what will you be looking for on it?
• How will you tell later whether a change on a scan is the tumor or the treatment?
• If a new spot turns up, can this be done again?

Where to go next

• Radiation therapy: the mask, the daily visits, and what comes after for the ordinary course of radiation, the mask, and the side effects of treating a larger area.
• Follow-up scans, and what the results mean for what the scans afterward are looking for, and for radiation necrosis.
• Cancer that has spread to the brain if that is why this has been offered.
• Brain surgery: what happens, and what comes after for what an operation involves, which is often the other thing on the table.
• Proton therapy: a different beam, and how people get to one for the other name people meet at the same appointment.
• Get help now if you need to talk to a person today.