Neurofibromatosis describes a group of genetic conditions that lead to the growth of tumors along the nerves. In the majority of cases, these tumors are benign but they can become cancerous in some cases.
Types of neurofibromatosis
There are two main types of neurofibromatosis:
- The most common form is neurofibromatosis type 1 (NF1), which occurs in 1 in 3000 births.
- Neurofibromatosis type 2 (NF2) is a less common form that is observed in around 1 in 35,000 births.
Although these two conditions share the same name, they are separate illnesses caused by different gene mutations.
Neurofibromatosis type 1
NF1 is a congenital condition that is present from birth, although some of the symptoms associated with the illness develop over time. The severity of symptoms varies between individuals but in the majority of cases, the skin is affected and is typically characterized by:
- Pale brown patches with smooth outlines, referred to as café au lait spots.
- Soft, benign tumors underneath or on the surface of the skin. These are called neurofibromas.
- Around a third of people affected by this condition also develop the following symptoms:
- Scoliosis or curvature of the spine
- High blood pressure
- Learning and behavioural difficulties
The underlying cause of NF1 is a genetic mutation, which causes derangement of the genetic material that governs the growth and development of the nerve cells. This leads to uncontrolled and abnormal growth of the nerve tissue. In about 50% of cases, the gene is inherited, while other cases are sporadic with the mutations developing independently of any family history of the condition.
At present, there is no available cure for NF1. Most people with this condition need to be routinely monitored for worsening symptoms and treated accordingly. Surgery may be advised to remove the tumors and correct bone deformities and medication may be prescribed to help control symptoms such as high blood pressure.
In addition, therapy is available to help people deal with any behavioural difficulties. A large proportion of people with NF1 manage to lead a fulfilled life with the help of careful monitoring and treatment but complications such as stroke can mean life expectancy is reduced by up to 15 years in some individuals.