Neurofibromatosis: types, symptoms, causes and treatment

The symptoms depend on the type. The NHS says NF1 symptoms are often mild but some people have symptoms that cause problems, that how severe they are usually depends on where the tumours are and how big they are, and that many symptoms are there from birth or start during early childhood, though some do not appear until later.

NF1 signs listed by the NHS are below. For NF2 the main symptoms come from tumours in the inner ear, as described in the comparison table.

• Light brown patches of skin (cafe-au-lait spots), which may be harder to see on brown and black skin.

• Freckles in the armpits or around the tops of the legs.

• Lumps on or just under the skin (neurofibromas) that can be painful or itchy, tending to appear during the teenage years or early 20s.

• Yellow-brown raised dots on the coloured part of the eye (iris) that do not usually affect vision.

• Eye problems such as a squint, reduced vision or a bulging eye.

• A large head and below average height, and learning difficulties.

Nerve Tumours UK says neurofibromatosis, collectively known as NF, is the medical group name for NF1, NF2-related schwannomatosis (NF2) and schwannomatosis (SWN). It describes NF as one of the most common neuro-genetic conditions, although it can still be classified as a rare condition, and says it manifests differently from person to person.

The NHS describes NF1 as a genetic condition where tumours grow on the nerves and skin, and NF2 (also known as NF2-related schwannomatosis) as a rare genetic condition where non-cancerous tumours grow on nerves in the brain, inner ear and spinal cord. Nerve Tumours UK says schwannomatosis is a very rare condition sharing some features with NF2, where people rarely develop growths on the hearing and balance nerves.

The NHS says most people with NF2 get tumours in their inner ear, which grow slowly and cause hearing loss, ringing or buzzing in the ears (tinnitus) and balance problems. Tumours can also form on the spinal cord and on the layers surrounding the brain (meninges), which do not always cause symptoms but can cause headaches, feeling or being sick, fits (seizures), blurred vision and vision loss, weakness in the face, and weakness, numbness or tingling in the hands and feet.

The NHS says children with NF2 often have eye problems such as a squint or childhood cataracts, lumps or marks on the skin, and foot drop.

The NHS says NF1 and NF2 are each caused by an altered gene. Sometimes the altered gene is passed on to a child by one of their parents, but sometimes a child can be born with the condition even if their parents do not have the altered gene. If you have NF1 or NF2, there is a 1 in 2 (50%) chance of passing the affected gene on to any child you have. Nerve Tumours UK says 1 in 2 of all diagnoses are the first one within the family.

The NHS says that if you have a close relative with NF2, such as a parent, you might be offered a genetic test, and a geneticist can explain the chance of any children you have being affected.

For NF1 the NHS says a GP who thinks you or your child might have it will refer you to a specialist for tests, which can include eye tests to check vision, an MRI scan to check for tumours in areas such as the brain, spine and tummy, and genetic tests.

For NF2 the NHS says tests may include hearing tests, eye tests and scans such as a CT or MRI scan, and you may see several specialists including an audiologist, an ophthalmologist and a geneticist. A genetic test is sometimes used to diagnose NF2.

The NHS says there is currently no cure for NF1 or NF2, but treatments can help manage symptoms and complications. You are supported by different healthcare professionals, which for NF1 may include a neurologist, an ophthalmologist and a dermatologist, with children also under a paediatrician.

Treatment depends on your symptoms and may include medicine to stop tumours growing, surgery to remove tumours that are at risk of causing problems, and radiotherapy to treat small tumours or pieces of a larger tumour that are left after surgery. If symptoms are not causing any problems, the NHS says your doctor may suggest waiting to see if any problems develop before starting treatment.

For NF2 the NHS also lists hearing aids and cochlear implants, and says most people with NF2 will need surgery at some point during their life to remove tumours from their inner ear, brain or spinal cord.

The NHS says NF1 is a lifelong condition that usually gets worse over time and affects everyone differently. It recommends a check-up at least once a year so changes can be picked up early, yearly blood pressure checks and eye checks (every year for children, every 2 years for adults), and a yearly mammogram from the age of 40 for women with NF1 to check for breast cancer.

The NHS lists possible complications of NF1 as high blood pressure, bone and joint problems such as bowed legs or scoliosis, a tumour on the optic nerve, depression and anxiety, and a higher risk of certain cancers. It says children with NF1 often have learning difficulties and may need extra support at school. NF1 and NF2 can affect life expectancy, and the NHS says your care team can discuss this with you.

The NHS says that if you have NF1 and are pregnant you may get problems such as narrowed arteries and high blood pressure. You may also get more tumours, or your tumours may get bigger and be itchy. It advises talking to your care team if you have NF1 and are pregnant or planning to get pregnant.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if you or your child keep getting headaches that do not go away or are getting worse, keep feeling or being sick, or have blurred vision or vision loss. For NF2 it says to call 999 if you have a seizure for the first time, or weakness or numbness in your face or down one side of your body.

See a GP if you think you or your child might have neurofibromatosis.

Nerve Tumours UK says its specialist NF nurse advisors are based within NHS trusts around the UK and that there is a national NF helpline for people without regional access to specialist services. Care is usually delivered by NHS specialist NF services with a team of specialists. Private genetic and neurology consultations exist, and results should be shared with your GP and NF service.