CNS lymphoma

A cancer of white blood cells that starts in the brain, the spinal cord, or the eyes. Why an operation to remove it is not the treatment. Why a steroid can take the answer away before anyone has it. And what the medicine that reaches the brain is actually like.

The short version

CNS lymphoma is a cancer of white blood cells. Most lymphomas start in the glands of the immune system. This one starts inside the brain, the spinal cord, or the eyes instead.

It is treated differently from almost every other tumor on this site. An operation to take it out is not the treatment. A small sample is taken to name it, and then the treatment is medicine that can reach the whole brain.

One thing is worth knowing on day one. A steroid can shrink this tumor fast, but only for a while, and that can take the answer away before anyone has it. Teams try to get the sample first. It is in the section on finding out, below.

The name on your report may be longer than the one at the top of this page. Your team may also send you to a blood cancer doctor as well as a brain doctor. Both are normal here, and neither means anything has gone wrong.

What is CNS lymphoma?

It is a blood cancer growing in the brain, not a tumor grown from brain cells. That one fact explains most of what follows.

Lymphoma starts in a white blood cell called a lymphocyte. These cells are part of how your body fights infection, and they travel everywhere. Most lymphomas start in lymph glands. When lymphoma starts in the brain, the spinal cord or the eyes and is nowhere else, it is called primary CNS lymphoma. CNS is short for central nervous system, which means the brain and the spinal cord together.

The eyes belong with the brain here, which surprises people. The brain, the back of the eye and the testicles are all guarded by a barrier that keeps most things out, including much of the immune system. A classification used by blood cancer doctors groups these places together and calls them immune sanctuaries. That is why a brain diagnosis comes with an eye examination.

It is rare, and that shapes your care. Because few people have it, most of what is known comes from small studies rather than large ones, and specialists still disagree about parts of the treatment. This page says where they disagree rather than smoothing it over.

Is it cancer? What does its grade mean?

Yes, it is cancer. The word your team may use is malignant.

There is no grade for this one, and that is not an oversight. Most brain tumors get a number from 1 to 4 that says how the cells look and behave. The international book that names brain tumors lists this one and prints no grade beside it at all. Beside other tumors it prints 1, 2 or 3.

The reason is that this is a lymphoma. Lymphomas are sorted by what kind of white blood cell they came from and where they are, not by the brain tumor scale. So if you are looking for your number and cannot find one, nothing is missing from your report.

What takes the place of a grade here is the type of cell and where it is. Your report will name the cell. Your scans and an eye examination say where it is. Those two things, not a number, are what the plan is built from.

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

It tends to grow deep, near the fluid spaces in the middle of the brain.

It also tends to be in more than one place at once, and its edges blend into the brain around it rather than stopping cleanly. Those two facts are the whole reason surgery is not the treatment, and they come up again further down.

Where it sits explains the symptoms people notice first. Deep in the brain are the paths that carry thinking, attention and memory between one part and another. So the first changes are often in how somebody thinks and behaves, rather than a single obvious thing going wrong.

Before you read the next part. What follows describes how tumors in the brain cause symptoms in general, and most of it fits this one. One part fits less well. Seizures happen with this tumor, but they are less common with it than with most other brain tumors, so treat that paragraph as something that happens to a minority here rather than to most people. That is not a reason to take a seizure less seriously. A first ever seizure is an ambulance call, and that rule below applies to you exactly as it does to anyone else.

One more part of it is written for other tumors rather than for this one. It says that medicines which bring swelling down do not change the tumor itself. Here a steroid changes both, and that is why the timing of one has a section of its own further down this page.

And one thing in the map of brain areas below. Its deep middle entry starts with pressure, because that is what a growth blocking the fluid does first. This one does not usually start that way. Here the first changes are the ones described above, in thinking and behavior. Pressure can still come later, and the symptoms section below says what to do about it.

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?

The commonest first sign is a change in thinking, memory or personality, and it is very often the people nearby who notice it before the person does.

That can look like confusion, forgetting things, losing the thread, or somebody simply not seeming like themselves. It is easy to put down to stress, low mood, or getting older.

Other common signs are weakness down one side, trouble with balance and walking, and the signs of pressure building up inside the head.

Symptoms usually build over weeks, not over months or years.

Eye symptoms belong on this list. Blurred vision, or floaters, which are small shapes that drift across what you are looking at. Eye involvement can also be completely silent. Most people whose eyes are involved notice nothing wrong with their sight, which is exactly why an eye examination is part of finding out and not something you ask for only if your sight has changed.

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.

Use the list above. It is the one to go by, and this page does not add a separate set of warning signs for this tumor on top of it.

The one rule that is genuinely yours arrives with treatment, not with the tumor. That rule is in the list above: the fever rule, and it is there because this treatment lowers the white blood cells that fight infection.

How do doctors find out it is this?

A scan raises the question. A small sample answers it.

An MRI scan usually comes first. Sometimes the scan itself is enough to make 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 suspect lymphoma, before anything has been proved.

Then tissue. A scan can suggest lymphoma. Only looking at the cells can say it. What you have is usually a stereotactic 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. How tissue is taken goes through that day, start to finish.

The sample is taken to name it, not to remove it. This is the part that is unlike most of this site. For most brain tumors the question is how much can safely come out. Here the operation is for the answer, and the treatment is medicine. There is one exception, and it is about pressure rather than cure: if pressure inside the head is rising fast, a surgeon may take some bulk away at the same time as the sample.

Why the steroid timing matters so much

A steroid can make this tumor shrink within days. That does not last, and it can cost you the diagnosis.

Steroids are given to a great many people with a brain tumor, to bring down swelling. For almost every other tumor they do nothing to the tumor itself. This one is the exception. Steroids act on lymphoma cells directly, and the tumor can shrink or fade off the scan quickly. Doctors have a name for what is left behind when it does: a ghost tumor.

The shrinking does not last. After a steroid, this tumor usually comes back within a short time. So a steroid on its own is not a treatment for it, however good the next scan looks. The treatment is the medicine that comes after the diagnosis.

That matters because a sample taken from a tumor that has already faded may not hold enough lymphoma to name. Samples taken after a steroid has been started are more likely to come back with no answer at all.

This is why teams often want a biopsy before starting steroids, if it is safe to wait. Steroids is the page for that medicine, and this is the one tumor on this site where a steroid acts on the tumor itself rather than only on the swelling around it.

That rule is less frightening than it sounds, and here is why.

It is a rule for your team, not a decision you have to police. The guideline that states it grades it as the weakest kind of recommendation, and grades the exception more strongly: if somebody is getting worse, the answer is to do the biopsy sooner, not to leave them without treatment.

If a steroid was started before anyone suspected lymphoma, that is common and it is not a mistake you have to fix. It usually happens in an emergency room, days before the word lymphoma is first said out loud. Teams work around it, and there is more than one way round it: the sample can be taken soon after that first dose, or the team can wait and look again later. Ask which one applies to you.

If you are already on a steroid, do not stop it yourself. Tell whoever is treating you that you are on one, and let them decide. Coming off a steroid suddenly can make you very ill.

A sample that cannot be named is a known situation with a known path. Sometimes the tumor has to be watched until there is enough of it to test again. Your team will tell you what they are waiting for.

What else gets checked, and why

Your eyes. An eye doctor looks into the back of the eye with a bright light and a lens, an examination called a slit lamp. It is done for everybody, not only for people whose sight has changed.

The fluid around your brain and spine. A sample of that fluid, taken with a needle in the lower back, can sometimes show lymphoma cells. It is not always needed, and a clear result does not rule this out.

The rest of your body. This sounds alarming. It is the opposite. To call something primary CNS lymphoma, doctors have to show it is not somewhere else, because lymphoma that started elsewhere and spread would be treated differently. Scans of the body, and sometimes a bone marrow sample, are how that is shown. Blood tests are done at the same time.

What do the words on my report mean?

Your report may not say "CNS lymphoma" at all. The name used by the international classification of brain tumors is primary diffuse large B-cell lymphoma of the CNS. It is long, and every part of it is doing a job.

• Primary means it started here rather than arriving from somewhere else.
• Diffuse large B-cell names the cell. B cells are one kind of lymphocyte, and these ones look large under the microscope.
• Lymphoma of the CNS places it in the brain and spinal cord.

B cell. The kind of white blood cell this starts from. Some of the treatment is aimed at a marker on the surface of those cells, which is why the cell type is worth knowing rather than skipping over.

You may meet a second name, from a different rule book. Blood cancer doctors updated their own classification a year after the brain one, and grouped this together with lymphoma of the back of the eye and of the testicles, under a heading about immune sanctuaries. Two books, two names, one disease. If your paperwork uses one and a website uses the other, nobody has made a mistake.

Old names turn up in older writing. Reticulum cell sarcoma and microglioma are both historical names for this disease. If you find them while reading, you have found something old rather than something new.

No grade. As above, there is no grade 1 to 4 for this one. Your pathology report walks through a report part by part, though the grade section of it will not apply to yours.

How is it usually treated?

The treatment is medicine, and it starts soon after the diagnosis.

Surgery does not treat it. A federal patient guide says it plainly: surgery is not used to treat primary CNS lymphoma. The reason is the shape of the disease rather than the skill of the surgeon. It spreads through brain tissue rather than pushing it aside, it is often in several places, and single cells sit beyond anything a scan can show. Taking out what can be seen would leave what cannot.

Who leads your care may be two people. A brain specialist and a blood cancer specialist often share it, because this is a blood cancer in a brain. Ask who your first call is, because with two teams it is easy for that to go unsaid.

The main drug is methotrexate, given at a high dose into a vein. The dose has to be high for a reason worth understanding: the brain is guarded by a barrier that keeps most drugs out, and only a high dose crosses it in useful amounts. This is why it is not a tablet you take at home.

Other drugs are usually given with it. Which ones vary. One of them, rituximab, is an antibody that sticks to a marker on B cells. Whether it adds benefit here is honestly still argued: one guideline panel could not reach agreement on recommending it.

Then a second phase, and this is where specialists disagree most. After the first course, a further treatment is usually given to keep it away. There is more than one accepted way to do it, including a stem cell transplant using your own cells, more chemotherapy, or radiation to the whole brain. Trials have not settled which is best.

What is agreed is the worry about radiation to the whole brain. It can cause lasting problems with thinking and memory, and that risk is higher in older people. Guidelines say it should be avoided or put off in older patients for that reason. What radiation to the whole brain involves is covered on its own page.

If the eyes are involved, treatment can be given into the eye as well as into a vein.

Chemotherapy into the spinal fluid is sometimes used and is genuinely disputed. Some studies found no benefit from adding it, others suggested some, it carries a risk of infection where the small device sits, and recent trials have largely stopped using it. If it comes up, asking why is entirely reasonable.

Age on its own does not decide this. What matters more is how well your kidneys work, because the main drug leaves the body through them, and how well you are otherwise. Guidelines say plainly that people should not be sorted by age alone. Where the full treatment is too much, a gentler version is used rather than nothing.

Ask about a clinical trial, early. For this disease the guideline does not hedge: it says every patient should be offered a suitable trial. That is unusually strong, and it is because so much here is still being worked out. Clinical trials explains what taking part involves. Suitable trials are not always available near you, which is worth knowing so that a "no" does not read as a door closing.

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

The hospital stays

Each round of the main drug usually means a few days in the hospital, and the reason is not the medicine going in. That part takes a few hours. The days afterwards are about getting it safely out again.

While you are there:

• Fluids run into a vein, in large amounts, to keep the drug moving through your kidneys.
• A medicine makes your urine less acidic, for the same reason. You may be asked to have your urine tested each time you pass it.
• A second medicine protects you from the first. It is called leucovorin, or folinic acid, and it starts a day or so after the main drug. It shields your normal cells while the treatment works on the lymphoma. It is not a sign anything has gone wrong.
• Blood is taken every day to measure how much of the drug is left. You go home when that level has dropped far enough, which is why the stay is a few days rather than a fixed number.
• Some medicines carry on at home for a few days after you leave.

Rounds usually come every few weeks, so there is a rhythm of going in and coming out. Ask your own team for your dates in writing.

Not everybody stays in. Some places now give this treatment without an overnight stay. If that is offered to you, it is a real option and not a corner being cut.

What it does to you

Mouth sores are one of the commonest problems this drug causes, and they can be bad enough to make eating hard. Say so early instead of putting up with them. There is treatment that helps.

Your kidneys are watched closely, which is what the blood tests and the fluids are about.

Blood counts fall, which brings tiredness and the risk of infection. That is where the fever rule matters most.

Tiredness is heavier than people expect and lifts slowly.

Thinking can be foggy during treatment. Some of that is the treatment, some is the tiredness, and some can be the tumor settling down. Raise it yourself at the next appointment. Nobody is likely to ask you first.

Everyday life

Infection is the thing to plan around, because the treatment lowers the cells that fight it. Your team will go through what that means for crowds, food and visitors during the weeks when counts are low. None of it is forever.

Tiredness is the symptom most likely to shape a week. Sleep does not clear it. Put whatever matters most into the part of the day when you are at your best.

Thinking and memory deserve saying out loud. If following a conversation or keeping track of appointments has got harder, that is worth reporting rather than hiding, because some of it can be helped and all of it is easier when the people around you know.

Work and driving are decided case by case. Driving law is set locally, so no website can settle it for you, this one included. Put that question to your team.

Seizures, if you have had one, have their own pages: what to do during a seizure and living with seizures.

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

Follow-up here means MRI scans, and eye examinations alongside them. If your eyes were involved at the start they are checked more often.

Reading one scan against the last is a page of its own. So is the wait between a scan and a phone call, which a lot of people find harder than the appointment itself.

Tell your team about new symptoms between scans, and this is not a formality. When this disease comes back, most of the time it is noticed because somebody reported something new, and only a minority of returns are found on a scan that was already booked. So the thing you notice matters as much as the appointment in the diary.

Ask for the schedule on paper. It should say when the next scan falls, when the eye appointment falls, and which person to call if something shifts before either of them.

If it comes back

It often comes back, even when the first treatment worked well. Saying so plainly is kinder than letting it arrive as a shock.

There is no agreed standard for what to do next. The authors of a review written for doctors say it outright: there are no approved treatments and no widely accepted standard approach for this situation. That is a real gap, and it is not the same as nothing being available.

What is used includes going back to the same main drug, using different drugs, higher dose treatment with a transplant of your own stem cells, and radiation. Which one fits depends on what you had the first time, how long the gap was, and how well you are.

This is the point where a trial is most worth asking about, for the same reason the guideline gives it such weight.

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 one there is something to add, because for some people there is a known reason. People whose immune system is weakened have a higher chance of getting this particular tumor. That includes people living with HIV, and people taking medicines that damp the immune system down after a transplant. If that is not you, this belongs in the same place as every other brain tumor: nobody knows. If it is you, it is worth knowing, and it changes nothing at all about whose fault this is.

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.

Beyond that, three things matter especially here.

You may be the reason the diagnosis gets made. When the first change is in thinking, memory or personality, the person living it often cannot see it. If you have been quietly wondering whether somebody is not themselves, that observation is medical information. Say it to the team, in front of them, and say what you have actually seen.

The fever rule is yours to know too. Once chemotherapy starts, a raised temperature means phoning at any hour. Often it is the person alongside who spots it first, before anybody has thought to reach for a thermometer. What a temperature means during chemotherapy sets out the number your own team will want you to use.

The changes in thinking are the hardest part to live with, and they are not them. Other people caring for someone with a brain tumor say this is the part nobody warned them about. It helps to have somebody to say that to who is not the person you are caring for.

What to ask your team

• What exactly does my report say the cells are?
• Is it in my eyes or my spinal fluid as well as my brain?
• Who is leading my care, and who do I call first?
• Am I on a steroid now, and how does that affect the sample?
• If my tissue could not be named, what happens next, and when?
• What is my first course of treatment, and how many rounds are planned?
• How long is each hospital stay likely to be, and could I have it without one?
• What is the second phase likely to be, and why that one for me?
• If radiation to the whole brain is suggested, what would it mean for my thinking?
• How are my kidneys, and does that change the plan?
• Is there a clinical trial I could join?
• Between appointments, what counts as worth phoning about?
• When is my next eye appointment?

Where to get support

• Getting help now, for the hour when reading has stopped helping and a voice would be better.
• The National Brain Tumor Society publishes patient material on this particular diagnosis, which is unusual for a tumor this rare.
• Lymphoma organizations cover the blood cancer side, including what low blood counts mean day to day.
• The specialist nurse attached to your team. With two specialties involved, that is often the one person who can see the whole plan at once.