Non-cancerous (benign) brain tumours

A tumour is called benign when its cells grow slowly, do not invade neighbouring tissue and do not spread around the body. That is a description of how the cells behave, not a promise that nothing will come of it: the skull does not stretch, and even a quiet-looking tumour takes up room the brain does not have to spare. This is where the trouble comes from — not from the tumour itself but from the pressure it puts on the part of the brain next to it, or from the way it blocks the flow of fluid. The reassuring part is everything else: most of these tumours can either be removed or watched for years with no treatment at all.

How a slow-growing tumour announces itself

The signs depend not on size but on which part of the brain has come under pressure. Because the tumour advances unhurriedly, the complaints build up over months or even years, and people get used to them.

• a headache unlike your usual ones: worse in the morning, worse when you bend over, cough or strain, waking you at night, sometimes with vomiting that comes without warning nausea;
• a first-ever seizure in an adult, one of the commonest reasons a tumour is found at all;
• double vision, loss of side vision, a fog in front of the eyes;
• weakness or numbness in the arm and leg on one side, unsteadiness, handwriting that has changed;
• trouble with speech, memory or arithmetic; changes in character and behaviour that the family notices before the person does;
• hearing loss and noise in one ear only, which is how a tumour of the hearing nerve behaves;
• disrupted periods, discharge from the breast, loss of sex drive and unexplained tiredness with a tumour of the pituitary, the pea-sized gland that runs the hormones.

In small children the picture is different: morning vomiting, a squint, delay in development and, in babies, a head that is growing too fast.

When to call an ambulance

Call an ambulance (in Spain, Italy, Portugal, Poland and Ukraine the single European number 112 is in use) if:

• a headache comes on out of nowhere and reaches its peak within seconds — that kind of pain points to bleeding rather than a tumour, but the place to sort it out is hospital;
• someone has a seizure for the first time, a seizure lasts more than five minutes, or seizures follow one after another;
• drowsiness and confusion are deepening and the person is hard to rouse;
• an arm and leg suddenly become weak, the face droops or speech is lost;
• a severe headache comes with repeated vomiting and vision that is getting worse.

Nobody in that state should drive, and nor should the one person left alone with them: help may be needed on the way.

Which tumours count as benign

There are several dozen kinds, each growing from its own tissue. Four are the ones most often seen.

• Meningioma, from the membranes that cover the outside of the brain. The commonest of all, and often found by chance on a scan done for something else.
• Low-grade glioma, from the cells that support and feed the nerve cells. In children this is usually a pilocytic astrocytoma, which grows over many years.
• Acoustic neuroma (a schwannoma), on the nerve between the inner ear and the brain.
• Pituitary adenoma, from the hormone gland at the base of the brain. It gives itself away either by an excess of one hormone or by pressing on the visual pathways.

Tumours are given a grade from one to four. Grade 1 is genuinely benign: it comes out and the matter is closed. Grade 2 is less straightforward, because a diffuse grade 2 glioma grows slowly but has no clear edge and over the years can turn into something more aggressive. That is why it is watched for life, even when the person feels perfectly well.

How the tumour is found

At the appointment the doctor asks how the complaints have changed, tests the strength of your arms and legs, your coordination, reflexes and visual fields, and looks into the back of the eye: a swollen optic disc gives away raised pressure inside the skull before any serious symptom appears.

The key investigation is an MRI scan of the brain with contrast. It shows the tumour itself, the swelling around it and any shift of neighbouring structures. A CT scan is quicker, is irreplaceable in an emergency and sees bone and fresh blood well, but small tumours, particularly at the skull base and in the back of the head, get lost on it: a normal CT scan does not rule a tumour out. An EEG finds no tumours whatsoever — it shows epileptic activity — and it is ordered alongside a scan, never instead of one. Blood tests do not answer this question either.

The final answer on what the tumour is and how fast it tends to grow comes from examining the tissue, taken at biopsy or after removal. There are exceptions: a pituitary adenoma is recognised from hormone blood tests and visual field testing, and an acoustic neuroma from the MRI scan and a hearing test, with no sample needed at all.

How it is treated

Treatment is chosen to fit the type of tumour, where it sits and what it is doing, and it does not always begin with an operation.

• Watching. A small meningioma or acoustic neuroma causing no symptoms is often simply followed with repeat scans at set intervals. If it has not grown in years, it is left alone.
• Surgery. The main option when the tumour is pressing on the brain. The surgeon lifts out a piece of bone, removes the tumour and puts the bone back. The pituitary is usually reached through the nose, with no cut on the head at all.
• Medicine instead of a scalpel. A prolactinoma, the pituitary tumour that makes prolactin, usually shrinks on tablets from the dopamine agonist group and needs no operation.
• Radiotherapy and radiosurgery. Used when the tumour sits somewhere that cannot be reached, or when a fragment has been left behind after surgery.
• Treating the effects themselves. Anti-epileptic medicines for seizures, a short course of steroids to settle the swelling around the tumour and, if fluid is not draining, a shunt.

If radiotherapy to the head and neck lies ahead, see a dentist before the course begins and have everything that needs treating dealt with: irradiated jaw bone heals badly, and having a tooth out after radiotherapy becomes a problem in its own right.

Recovery and getting back to ordinary life

Most benign brain tumours are treated successfully, but coming back to yourself after surgery or radiotherapy can take a long time. A heavy tiredness lingers, concentration is harder, memory lets you down, difficulties with speech, vision or movement sometimes remain, and mood shifts. Some of these effects do not show up straight away but months after the treatment ends.

What helps is rehabilitation and therapeutic exercise, a speech and language therapist where speech has suffered, an occupational therapist who works out how to fit the home and the daily routine around what you can manage now, and a psychologist, because anxiety after a diagnosis like this is entirely normal.

Driving is a subject of its own. With seizures, and after brain surgery, you must not drive for a period, and the authority that issues driving licences has to be told. The timescales and the rules differ from country to country, so check yours with your doctor. For the same reason, do not swim alone or work at height while seizures are not under control. Follow-up scans go on for several years: a tumour can come back and, occasionally, change to a more aggressive character.

What genuinely raises the risk

The cause of most of these tumours is unknown. Only a few things are reliably linked to them: age, past irradiation of the head (radiotherapy given in childhood, for instance) and rare inherited conditions such as neurofibromatosis types 1 and 2, tuberous sclerosis and Li-Fraumeni syndrome. Meningiomas are noticeably more common in women, and European regulators warn of their link with long-term use of certain progestogens at high doses, in particular cyproterone acetate; if you are on such treatment, discuss how long the course should last with your doctor.

Mobile phones, knocks to the head, stress and food supplements, on the other hand, are not on that list: for all the looking that has been done, there is no convincing evidence that they play a part.

Online consultation with a doctor

A remote appointment earns its place where what is needed is an explanation rather than an examination. Reading the scan report together and working out what "space-occupying lesion" actually means. Deciding whether a new complaint is worrying or is a consequence of treatment already given. Sorting out side effects of anti-epileptic medicines, preparing questions for the neurosurgeon, planning rehabilitation, talking through the return to work and to driving.

The limits are plain. No conversation replaces a scan, and with a sudden severe headache, a seizure, deepening drowsiness or sudden weakness down one side, what is needed is not a consultation but an ambulance.

This material is for information only and does not replace medical advice.