Neurofibromatosis is the name for a number of genetic conditions. It causes multiple tumours to develop that affect the nervous system.
Tumours are abnormal tissue growths. In neurofibromatosis, the tumours are usually non-cancerous, or benign.
Types of neurofibromatosis
There are two main types of neurofibromatosis:
- Neurofibromatosis type 1 (NF1) is the most common type of neurofibromatosis, occurring in about 1 in 3,000 people.
- Neurofibromatosis type 2 (NF2) is the least common type of neurofibromatosis, occurring in about 1 in 25,000 people.
Despite sharing the same name, the two types of neurofibromatosis are separate conditions that have different causes and symptoms.
This section is about NF2.
Find out more about neurofibromatosis type 1.
Symptoms
Almost everyone with NF2 has tumours that start growing on the nerves responsible for hearing and balance. These typically cause symptoms such as:
- gradual hearing loss, which usually gets worse over time
- ringing or buzzing in the ears (tinnitus)
- balance problems, particularly when moving in the dark or walking on uneven ground
Tumours can also develop inside the brain or spinal cord, or the nerves to the arms and legs. This can cause symptoms such as weakness in the arms and legs and persistent headaches.
Read more about the symptoms of neurofibromatosis type 2.
Causes
NF2 is caused by a genetic mutation. This is where the instructions that are carried in all living cells become scrambled in some way. As a result, one or more of the body’s processes do not working correctly.
In half of all cases of NF2, the genetic mutation is passed down by a parent to their child.
In other cases, the genetic mutation appears to develop on its own in a child with no family history of the condition. This is called a sporadic mutation.
Read more about the causes of neurofibromatosis type 2.
Treatment
There is currently no cure for NF2. Treatment involves managing the symptoms as and when they occur. Surgery can be used to remove tumours on the hearing and balance nerves. However, it can cause complete deafness or facial weakness, so decisions about surgery should be made by specialist NF2 teams.
Most people with NF2 eventually develop significant hearing loss and often benefit from learning to lip read or using a hearing aid. Sometimes, special implants can be inserted to aid hearing.
Read more about treating neurofibromatosis type 2.
Outlook
The outlook for NF2 can be highly variable. Some people’s symptoms get worse rapidly. For other people, the condition progresses much more slowly. However, most people with NF2 will eventually lose their hearing and some people will require a wheelchair or other type of mobility device.
Tumours that develop inside the brain and spinal cord can place a considerable strain on the body and shorten life expectancy. The average life expectancy for someone with NF2 is 65 years of age.
However, this is expected to increase as treatment improves.
