Follow-up scans, and what the results mean

The scans that carry on after treatment. How often they happen, and what your team compares them with. What the words on the report mean. And why a scan that looks worse is not always worse.

The short version

Scans carry on after treatment. They exist so that a change is picked up early enough to do something about. Three things are worth knowing before your next one. A scan that looks worse does not always mean the tumor has grown. Treatment itself causes changes that look like growth, in the months after radiation and sometimes years later, and your team has rules for telling them apart. The word "stable" on a report means the change was inside an agreed band, not that nothing moved at all. And for most people the hardest part is not the scan. It is the gap between the scan and the answer, so ask for the two to be booked close together.

What is a follow-up scan?

It is the same kind of scan you have had before, done again, so your team can see what has changed since last time.

Almost always it is an MRI, and it works the same way it did the first time. Your MRI scan covers the machine, the noise, the dye, and what your options are if you find small spaces hard. None of that changes because the scan is a follow-up.

What changes is what the scan is for. The first one was asked so somebody could find out what was there. This one is asked so somebody can compare.

Why do the scans carry on?

Because a change is easier to deal with when it is found early, while more of the options are still open.

Follow-up is closest together in the first months and years after treatment. It spreads out after that. Your team is watching for three things at once: the tumor coming back or growing, the effects of the treatment you had, and anything new that would explain a symptom you have told them about.

It is not a test you can pass or fail. It is the part of the plan that keeps your team's picture of you up to date.

There is one thing a scan cannot do, and it is worth knowing early. It shows what is big enough to see. So a scan with nothing left to measure on it is a real and welcome thing, and it still is not the same as saying nothing is there. That is why scans carry on even after an operation that went as well as anybody hoped, and it is not a sign that your team is holding something back.

What happens to the pictures

The short answer is that your new scan is not read on its own. It is read against your old ones.

1. Your pictures are lined up with the earlier ones. The old scans are not filed away. They are the thing the new one is measured against.
2. One scan is the starting point. After surgery it is usually the scan done in the first day or two. After radiation, the current version of the rules described further down this page sets the starting point at a scan about four weeks after the last session. Everything later is compared with that.
3. The same parts get measured. Mostly this is the area that brightens when the dye goes in. That is the part the rules are built around.
4. The change gets a word. Smaller, bigger, or somewhere in between. The next section is about those words.
5. The word is not the whole answer. Your team puts it together with how you are doing and what medicines you are on before deciding anything.

Step five is the one to hold on to. A report describes a picture. Your team treats a person.

How often, and how long until I hear?

There is no single schedule that fits everybody, so this page does not print one. How often you are scanned depends on your diagnosis, the treatment you had, and how things have gone since. The shape is usually the same: closer together at first, further apart as time passes.

So ask for yours, in writing, and ask what would change it.

The wait for the result is local too. It depends on your hospital, not on your scan, and it is fair to ask before you leave: when will this be read, and who is going to call me?

If something changes between scans, you do not have to wait for the next one. Asking for a scan to be brought forward is an ordinary thing to do, and telling your team about a new symptom is what gets that decided.

What is the day itself like?

Much like the last one. Same machine, same noise, same holding still.

The person running the scanner will not be able to tell you anything. They are not the person who reads it, so a result is not theirs to give. That silence is not a signal, in either direction, and a lot of people read it as one on the drive home.

Afterward you go straight back to whatever you were doing. There is nothing to recover from and nothing you have to avoid. The one exception is if you were given something to help you lie still. Then follow the instructions you were given about driving.

The waiting, and what actually helps

The wait has a name. Scanxiety. In a review of people being followed after cancer surgery it was close to universal, and for most of them the worst part was not the scan. It was the days between the scan and the answer.

Here is the honest state of it. In that same review, five trials tested ways of making the wait easier against ordinary care. None of them reduced it. Scanning people more often did not help either, which is worth knowing if you have wondered whether closer follow-up would settle your mind. So this page is not going to promise you a technique.

What is left is the part you can arrange, and it is not nothing:

• Ask for the scan and the results appointment to be booked close together. Nobody has shown that closing that gap fixes the waiting. It is put first because it is the part of this that is yours to ask about, and because the gap is what people describe as the worst of it.
• Ask who calls you, and when. Knowing which day it might come stops every day being that day.
• Decide in advance whether you want to read the report before you have spoken to anyone. In the United States it can appear in your online records first. Waiting for your results goes through that choice, and it is the same choice here.
• Plan something for the waiting days. Not to be brave about it. Because they are days, and they pass better with something in them.
• Say it out loud to your team. People assume this part is theirs to carry privately. It is a normal thing to raise at an appointment, and sometimes the timing can be changed once somebody knows.

And if the waiting is bigger than that, you are not being dramatic and you do not have to wait for an appointment. Get help now has people you can talk to today.

What the words on the report mean

Reports about brain tumors use a small set of words for change, and they come from an agreed set of rules. The rules are called RANO, short for Response Assessment in Neuro-Oncology.

Two things about those rules are worth knowing before you read the words.

The first is that they were built for research studies. The paper describing the current version says so plainly: the criteria are primarily intended for clinical trials. They exist so a treatment tried in one hospital can be compared with the same treatment tried in another. They are not a set of instructions about you.

The second is that each word covers a range, not a point. The rules set cut-offs. The word you get is whichever band your change fell in.

That is what makes stable an easy word to misread. Stable does not mean identical. It means the change was too small to count as shrinking and too small to count as growing. A tumor that got a little smaller and one that got a little bigger can both be called stable. The word does not say which of those happened to you.

The other words work the same way. Response means it shrank by more than the agreed amount. Progression means it grew by more than the agreed amount. A smaller change in the shrinking direction sometimes gets a word of its own, which is why a report can name something between the two.

If progression is the word on your report, it is not the end of the plan. It is the point where the plan gets looked at again, and there are usually still things to try. Your own tumor page goes through what those are for your diagnosis, and it is the right place for that conversation rather than this one.

None of this is a reason to distrust your report. It is a reason to ask one question at the appointment: compared with which scan, and by how much? That turns a word back into the measurement it came from.

What if the scan looks worse?

A scan can look worse because of the treatment rather than because of the tumor. It has a name, and it is one of the things people most often meet without any warning: pseudoprogression.

What is on the pictures is repair, not growth. Treatment kills tumor cells, the area around them swells and becomes leaky, and dye collects there. That looks almost exactly like a tumor getting bigger. The window for it is roughly the first three months after radiation ends.

It is common. Common enough that the rules your team follows have a step built in for it, rather than treating it as a surprise. There is no reliable figure to put here, because studies that counted it in different ways came back with very different answers.

It is not only a problem on the screen. The same swelling can press on brain tissue and give you real symptoms, which is the part almost nobody is warned about. Those symptoms are treatable, so report them rather than waiting for a scan to explain them.

So a repeat scan is often the answer, instead of a change of plan. Inside the first twelve weeks after radiation, new brightness is not enough on its own. It is only called growth when something else backs it up:

• another scan a few weeks later shows the same thing, or
• the new area sits outside where the radiation was aimed, or
• a sample shows it.

You may be offered a more detailed kind of scan to help sort it out. Those help, and they do not settle it. Older reviews said outright that they cannot reliably tell the two apart. Newer ones report them doing better than that. Both agree on where the certainty comes from: a sample of tissue, or time.

Waiting is the hard part, because time is the one thing you did not want to spend on this. It is not your team dithering, and it is not something being kept from you. Ask what they think they are seeing, what a repeat scan would settle, and what you should report while you are waiting. Those three answers make the weeks in between something you can plan around.

What if something shows up much later?

There is a second look-alike, and it works on a much longer timescale. Well after radiation has finished, tissue inside the treated area can break down and die, and the body's reaction to that shows up brightly on a scan. The name for it is radiation necrosis, and it is easily mistaken for the tumor returning.

This one is not only on the screen either. The swelling around it can press on brain tissue and cause symptoms. Steroids often settle it. Sometimes another medicine is added, and sometimes an operation is needed. Steroids covers that medicine, including why your team asks what dose you are on before a scan.

The clearest numbers come from one kind of radiation, and it may not be yours. They are from people given a focused, high-dose treatment called stereotactic radiosurgerystereotactic radiosurgery: Radiation aimed at a small target, in one visit or a few. There is no cutting, despite the name. See the glossary, most of them for meningiomas or for tumors that began in another part of the body. In that group it turned up around eight months afterward on average, with a spread running from one month to well over three years. How likely it is varied a lot even inside that group, depending on what was treated and how strong the dose was, and it is not the same picture as the weeks of daily treatment most people with 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 have. Ask your own radiation team what it means for the treatment you had. If that focused treatment is the one you had, what it is and what the day is like covers the rest of it.

The useful part is the same as the section above. A changed scan does not automatically mean one thing, and your team will usually want another look before anyone decides which thing it is.

What you can do around a scan

Small things, and they are worth doing because most of the rest of this is not in your hands.

• Book the results appointment when you book the scan, if your hospital lets you. This is the most useful thing on the list.
• Ask what this scan will be compared with. Then you know what "stable" would be stable against.
• Keep your own copies. Ask for your pictures on a disc or a link, and keep your reports together. They travel with you if you ever change hospital or want another opinion.
• Write your symptoms down as they happen, with dates. At the appointment you are reading rather than remembering, and a change that started six weeks ago is worth more to your team than "a while".
• Take somebody with you to the results appointment. Two people hear more than one, and the second person can write while you listen.
• Say what you want to be told, and how. Some people want every detail. Some want the headline. Both are allowed, and your team cannot guess.

Why do they want to scan me again so soon?

Being sent back sooner than you expected is frightening. It usually means something more ordinary than it feels like.

One common reason is the one in the section above: something on the last scan needs a second look before anybody calls it anything. The rules build that in on purpose. A repeat a few weeks later is often how the question gets answered, because waiting is what separates a treatment effect from real growth.

Other reasons are more mundane. The pictures may not have come out well enough to compare. A different kind of scan may be needed to answer a specific question. Or the plan may have changed for a reason that has nothing to do with what was seen.

Ask which of those it is. It is a fair question, the answer is usually short, and it saves you weeks of assuming the worst of them.

Two other repeats trip people up and neither of them is this. Your MRI scan covers the scan just before surgery and the scan just after it.

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

A radiologistradiologist: A doctor trained to read scans and write down what they show. The report goes to the doctor who asked for the scan, who then tells you. One who specializes in the brain and spine is called a neuroradiologist. See the glossary reads the pictures and sends a report to the doctor who ordered the scan. That doctor is the person who talks you through it. Your MRI scan has the detail on who does what.

What is different about a follow-up scan is that the report is a comparison. It will refer to earlier scans, sometimes by date. If you are reading it on your own, that is often what makes it hard to follow.

Hearing nothing is not a result. Ask what you should expect: whether somebody calls either way, or only if there is something to say. Then you know what silence means, instead of turning it over for a week.

If a report lands before anyone has spoken to you and it knocks the wind out of you, you can ask your team to start again from the top. That is a reasonable thing to ask for, and asking does not use anything up.

What to ask your team

• How often will I be scanned, and what would change that?
• Can I book the scan and the results appointment at the same time?
• What is this scan being compared with?
• Will the report appear in my online records before we speak?
• Do you call me either way, or only if there is something to say?
• If the scan looks worse, how will you tell treatment effect from growth?
• If we are not sure, what happens next: another scan, a different scan, or a sample?
• What should I call you about between scans?
• Can I have a copy of my pictures and reports for my own records?
• Is this scan being discussed at a tumor boardtumor board: A meeting where specialists talk through one person's case together: the surgeon, the cancer doctor, the lab, and whoever read the scans. You are not there. What they decide is advice your own doctor goes through with you. See the glossary?
• Am I likely to get radiation necrosis from the radiation I had, and what would it look like?

Where to go next

• Your MRI scan for the scan itself, the dye, and the machine.
• The extra scans before treatment for what those same extra scans are used for before an operation or radiation.
• Waiting for your results for the longer wait after tissue has been taken, and for the choice about reading a report on your own.
• Your pathology report, part by part for the other report, the one that names your tumor.
• Radiation therapy for the treatment behind both of the scan changes on this page.
• Watching a tumor, step by step if your scans are part of a plan to watch a tumor rather than treat it.
• Brain tumor types for what follow-up usually looks like for your own diagnosis.
• Get help now if you need to talk to a person today.