National Institutes of Health. Prognosis NF-1 is a progressive and diverse condition, making the prognosis difficult to predict. The NF-1 gene mutations manifest the disorder differently even amongst people of the same family. This phenomenon is called variable expressivity. For example, some individuals have no symptoms, while others may have a manifestation that is rapidly more progressive and severe. For many NF-1 patients, a primary concern is the disfigurement caused by cutaneous/dermal neurofibromas, pigmented lesions, and the occasional limb abnormalities. However, there are many more severe complications caused by NF-1 like increased cancer risk, a plexiform neurofibroma has a 10-15% chance of developing into a MPNST (Malignant Peripheral Nerve Sheath Tumour) . Many NF patients live perfectly normal and uninterrupted lives. Epidemiology NF-1 is estimated to affect around 25,000 people in the UK. See also Neurofibromatosis type II References External links Deficiencies of intracellular signaling peptides and proteins Neurological disorders Neuro-cardio-facial-cutaneous syndromes RASopathies tr:Nörofibromatoz tip 1