Neurofibromatosis type 1 (NF1) can be challenging to diagnose owing to the wide variation in symptoms and manifestations. Patients often visit different specialists and a physician with expertise in NF1 is needed for an accurate diagnosis.1–3
A: The diagnostic criteria for NF1 are met in an individual who does not have a parent diagnosed
with NF1 if two or more of the following are present:4
B: A child of a parent who meets the diagnostic criteria specified in “A” merits a diagnosis of NF1 if one or more of the criteria in A are present.
Adapted from: Legius E et al. Genet Med. 2021;23(8):1506–1513.4
*If only café-au-lait macules and freckling are present, the diagnosis is most likely NF1 but exceptionally the person might have another diagnosis such as Legius syndrome. At least one of the two pigmentary findings (café-au-lait macules or freckling) should be bilateral.
†Sphenoid wing dysplasia is not a separate criterion in case of an ipsilateral orbital plexiform neurofibroma.
*If only café-au-lait macules and freckling are present, the diagnosis is most likely NF1 but exceptionally the person might have another diagnosis such as Legius syndrome. At least one of the two pigmentary findings (café-au-lait macules or freckling) should be bilateral.
†Sphenoid wing dysplasia is not a separate criterion in case of an ipsilateral orbital plexiform neurofibroma.
Due to the complex nature of NF1, overall management of the condition requires a patient-centric, multidisciplinary approach including oncologists, surgeons, general practitioners, neurologists, dermatologists and ophthalmologists.3,5
*The management options listed are not exhaustive.
Complete surgical resection is the best option for patients with PN, with the goal of treatment to improve or prevent a PN-related morbidity.5,7 The benefits and risks must be considered on a case-by-case basis.
Several factors should be considered, including:5
- Patient age
- PN-associated morbidities – such as pain, disfigurement and functional impairment
- Future risk of PN causing morbidities – for example, PN adjacent to vital structures, such as the spinal cord, may not cause morbidity at present, but are at risk of future morbidity should the PN grow
- PN growth rate – rapidly growing PN, (> 20% increase in PN volume in the previous year) with impending morbidity is likely to be a candidate for surgery
Complete surgical resection can be challenging. As PN are highly vascularised with an infiltrative nature, resection is associated with a high risk of nerve damage, excessive bleeding for large tumours, functional impairment and delayed wound healing.9
Incomplete resection can also result in tumour regrowth.9
Regular clinical evaluations should be carried out at least annually, or more regularly as required, to ensure developing manifestations are identified as early as possible.3,10
These clinical observations should focus on:3
These clinical observations should focus on:3
Adapted from: Miller DT et al. Pediatrics. 2019;143(5):e20190660 and Hersh J et al. Pediatrics. 2008. 121(3):633–642.3,11
*Some specialists recommend performing an MRI of the head upon a diagnosis of NF1 being made to determine if an optic pathway glioma is present.11
ADHD, attention deficit hyperactivity disorder; MRI, magnetic resonance imaging; NF1, neurofibromatosis; PN, plexiform neurofibroma.
healthcare professional