Neurofibromatosis is a group of genetic conditions that cause tumours to grow on nerves and produces abnormalities in the bones and skin.

The most common form is neurofibromatosis Type 1 (NF1). It may cause dark spots to form on the skin that are similar to birthmarks (called café-au-lait spots). NF1 can cause tumours (neurofibromas) on or under the skin, in the eyes, or in the nervous system (brain and spinal cord). These tumours are often not cancer but, in some cases, can turn into cancer. NF1 also can cause developmental problems as a child grows that affect learning and memory.

There is no cure for neurofibromatosis, but treatment may relieve symptoms. Some people choose to have large or highly visible tumours removed by surgery. Surgery to remove tumours of the spinal cord, brain, or other nerves under the skin may be needed if the tumours are causing pain or disfigurement.