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Neurofibromatosis is a genetic conditions, also known as von Recklinghausen's disease. It is abbreviated as NF.

It comes in several flavours:

  1. Neurofibromatosis type 1 - NF1 (peripheral).
  2. Neurofibromatosis type 2 - NF2 (central).
  3. Neurofibromatosis type 3 - Schwannomatosis.

Neurofibromatosis type 1

  • Autosomal dominant.


Features (need 2/7 to diagnose):[1]

  1. Two or more neurofibromas or one plexiform neurofibroma.
  2. Café-au-lait spots.
  3. Freckles in axilla or inguinal area.
  4. Optic nerve glioma.
  5. Iris hamartomas (Lisch nodules).
  6. Sphenoid dysplasia or typical long-bone abnormalities (e.g. bowing).
  7. First-degree relative with NF1.


Diagnostic criteria CAFE SPOT:[2]

  • Café-au-lait spots.
  • Axillary or inguinal freckling.
  • neuroFibroma (two or more) or plexiform neurofibroma (one).
  • Eye hamartomas (Lisch nodules).
  • Skeletal abnormalities, e.g. sphenoid dysplasia, leg bowing.
  • Positive family history. †
  • Optic Tumour (optic nerve glioma).


  • † One could include paraganglioma here.

Other associations

Possible association


Neurofibromatosis type 2

  • Caused by mutations in the NF2 gene;[7] this gene is also known as merlin.[8]
  • Reduced life expectancy.
  • Mean age at diagnosis: 35years.


Features (need 1/3 to diagnose):[9]

  1. Bilateral CNVIII masses on imaging.
  2. Unilateral CNVIII mass + first-degree relative with NF2.
  3. First-degree relative with NF2 and 2/4 of the following:
    1. Meningioma (meningothelial meningioma) up to 50% of the cases.[10]
    2. Glioma, mostly spinal ependymomas (up tp 20% of NF2 cases affected).
    3. Schwannoma.
    4. Juvenile cataract.

Mnemonic MISME:[11]


  • Cerebral microhamartomas.
  • Schwannosis (Schwann cell proliferations).
  • Peripheral neuropathy.


  • Cortical proliferations of meningeothelial cells around small vessels.
  • May occur within NF2 and sporadic.
  • Associated with seizures and/or headaches.
    • Often asymptomatic.

See also


  • Autosomal dominant.
  • Prevalence: 1:155000 (UK).
  • Distinct entity from NF2, mainly due to absence of vestibular schwannomas.
  • Mean age at diagnosis: 40years.
  • Life expectancy better compared to NF2.



  1. Two or more non-intradermal schwannomas.
  2. Radiological exclusion of vestibular schwannoma.
  3. NF2-mutation excluded.
  4. One schwannoma or meningioma and one relative with confirmed schwannomatosis.
  5. Germline SMARCB1 or LZTR1 variant and histologically confirmed schwannoma or meningioma.


  • INI1 mosaic pattern in schwannomas.[13]


  1. URL: Accessed on: 3 May 2010.
  2. URL: Accessed on: 30 May 2011.
  3. Alexakis, N.; Connor, S.; Ghaneh, P.; Lombard, M.; Smart, HL.; Evans, J.; Hughes, M.; Garvey, CJ. et al. (2004). "Hereditary pancreatic endocrine tumours.". Pancreatology 4 (5): 417-33; discussion 434-5. doi:10.1159/000079616. PMID 15249710.
  4. Agaimy A, Hartmann A (October 2010). "[Hereditary and non-hereditary syndromic gastointestinal stromal tumours]" (in German). Pathologe 31 (6): 430–7. doi:10.1007/s00292-010-1354-6. PMID 20848108.
  5. Harrison B, Sammer D (September 2014). "Glomus tumors and neurofibromatosis: a newly recognized association". Plast Reconstr Surg Glob Open 2 (9): e214. doi:10.1097/GOX.0000000000000144. PMC 4229273. PMID 25426397.
  6. Castoldi, L.; De Rai, P.; Marini, A.; Ferrero, S.; De Luca, V.; Tiberio, G. (2001). "Neurofibromatosis-1 and Ampullary Gangliocytic Paraganglioma Causing Biliary and Pancreatic Obstruction.". Int J Gastrointest Cancer 29 (2): 93-98. PMID 12754392.
  7. Online 'Mendelian Inheritance in Man' (OMIM) 101000
  8. Online 'Mendelian Inheritance in Man' (OMIM) 607379
  9. URL: Accessed on: 3 May 2010.
  10. URL: Accessed on: 26 October 2010.
  11. URL: Accessed on: 20 February 2012.
  12. Evans, DG.; Bowers, NL.; Tobi, S.; Hartley, C.; Wallace, AJ.; King, AT.; Lloyd, SKW.; Rutherford, SA. et al. (Jun 2018). "Schwannomatosis: a genetic and epidemiological study.". J Neurol Neurosurg Psychiatry. doi:10.1136/jnnp-2018-318538. PMID 29909380.
  13. Caltabiano, R.; Magro, G.; Polizzi, A.; Praticò, AD.; Ortensi, A.; D'Orazi, V.; Panunzi, A.; Milone, P. et al. (Jun 2017). "A mosaic pattern of INI1/SMARCB1 protein expression distinguishes Schwannomatosis and NF2-associated peripheral schwannomas from solitary peripheral schwannomas and NF2-associated vestibular schwannomas.". Childs Nerv Syst 33 (6): 933-940. doi:10.1007/s00381-017-3340-2. PMID 28365909.