Flat, light brown spots on the skin
called ‘café au lait’ spots
What is NF1?
Neurofibromatosis (NF) is a rare, progressive, genetic condition, with the most common type being neurofibromatosis type 1 (NF1). NF1 can impact every organ system and be involved in the development of non-malignant (non-cancerous) tumours that may affect the brain, spinal cord and nerves.1,2
NF1 is also one of the most common inherited disorders and is caused by a mutation or flaw in the NF1 gene. Half of all people with NF1 are estimated to inherit the mutation from a parent while the other half have no family history.1-3
What is NF1-PN?
Up to 50% of people with NF1 may develop non-malignant tumours on the nerve sheaths called plexiform neurofibromas (PN).4
PN can appear anywhere inside or outside of the body. While they are often identified in infancy or childhood, the impacts of PN can persist into adulthood. As a lifelong condition, PN may also appear later in a person's life. Some PN can grow fast and become large, which can progressively interfere with normal physical functions. 4,5,6
Although PN may start as non-malignant, PN will later become cancerous in a small proportion (~10%) of adults and can be associated with reduced lifespan.7,8
Initial signs of NF1 may include:
The severity of NF1 can vary significantly and people with the disease may not develop every symptom.4
Soft lumps on and under the skin
Neurofibromas
Patients with NF1 may also experience:
Reference.4
Freckling in unusual places
such as the armpits or groin area
Optic gliomas
tumours that develop in the cells surrounding the optic nerve
Bone issues
Increased head size
Scoliosis
Back bone deformities
Small stature
Tiny bumps on the iris of the eye
called 'lisch nodules'
Delayed or early puberty
Neurocognitive differences
Hypertension
High blood pressure
References
- Chong, S. Lifelong management of neurofibromatosis patients. J Korean Neurosurg Soc. 2025;16;68(3):261–271.
- Ly KI, et al. The diagnosis and management of neurofibromatosis type 1. Med Clin N Am. 2019;103:1035-1054.
- Solem EP, et al. Factors associated with parental knowledge of neurofibromatosis type 1 (NF1): parental affected status and genetic counseling. J Genet Couns. 2020;29:1151-1158.
- Miller DT, et al. Health supervision for children with neurofibromatosis type 1. Pediatrics. 2019;143(5).
- Hirbe AC, et al. Neurofibromatosis type 1: a multidisciplinary approach to care. The Lancet Neurol. 2014;13(8):834-843.
- Abdelmoughit E, et al. Plexiform neurofibroma of the thigh: management experience and review of literature. J Pioneer Med Sci. 2015;5:103–106.
- Nguyen R, et al. Growth dynamics of plexiform neurofibromas: a retrospective cohort study of 201 patients with neurofibromatosis 1. Orphanet J Rare Dis. 2012;7:75.
- Gross A, et al. Association of plexiform neurofibroma volume changes and development of clinical morbidities in neurofibromatosis 1. Neuro-Oncol. 2018;20(12):1643–1651.
Veeva ID: GL/UNB-NF1/0097