Overview
- Two main types: localized (localized cutaneous or intraneural) and expansive (diffuse cutaneous or plexiform).
- Pathology demonstrates proliferation of majority of peripheral nerve elements.
- As a simple heuristic: schwannomas originate from Schwann cells whereas neurofibromas originate from majority of peripheral nerve elements.
- On histopathological section, collagen bundles can form a "shredded-carrot" appearance.
Localized
Localized cutaneous neurofibroma
The most common form of neurofibroma
- Localized cutaneous neurofibromas are pedunculated subcutaneous nodules that arise from the dermis or subcutaneous fat and protrude from the skin. They are circumscribed and originate from small, cutaneous nerves. On gross pathology, they are shinny and tan-white.
Intraneural neurofibroma
- Intraneural neurofibroma produce a fusiform expansion of a large nerve or nerve root.
- Whereas schwannomas form an eccentric, encapsulated tumor within the nerve, intraneural neurofibromas infiltrate the nerve and twist and stretch the nerve fibers (called dolioectasia).
- Neurofibromas CANNOT be resected from the nerve because they envelop the nerve fibers (on the contrary, schwannomas can be resected from the nerve).
Expansive
Diffuse cutaneous neurofibroma
- Diffuse cutaneous neurofibromas form plaque-like subcutaneous enlargements.
- Typically form in the head and neck region.
Plexiform neurofibroma
- Plexiform neurofibroma involves multiple adjacent nerve fascicles and has a vermiform (worm-like) appearance and feel.
- The overlying skin is stretched and thinned and the plexiform neurofibroma feels irregular and torturous to palpation.
Sporadic vs NF-1
Sporadic Neurofibroma
- Isolated, localized neurofibroma (cutaneous or intraneural)
Neurofibromas strongly associated with NF-1
- Multiple localized neurofibromas
- Diffuse neurofibromas
- Plexiform neurofibromas
Sporadic Neurofibroma
- Isolated, localized neurofibroma (cutaneous or intraneural)
Neurofibromas strongly associated with NF-1
- Multiple localized neurofibromas
- Diffuse neurofibromas
- Plexiform neurofibromas
References
- Adesina, Adekunle M., Tarik Tihan, Christine E. Fuller, and Tina Young Poussaint. Atlas of Pediatric Brain Tumors. Springer, 2016.
- Bland-Sutton, John. Tumours, Innocent and Malignant; Their Clinical Characters and Appropriate Treatment. New York?: Funk, 1911. http://archive.org/details/tumoursinnocentm1911blan.
- Gray, Frangoise, Charles Duyckaerts, and Umberto De Girolami. Escourolle and Poirier’s Manual of Basic Neuropathology. OUP USA, 2013.
- “Neuropathology for the Neuroradiologist: Antoni A and Antoni B Tissue Patterns | American Journal of Neuroradiology.” Accessed July 9, 2018. http://www.ajnr.org/content/28/9/1633.
- Newton, Herbert B. Handbook of Brain Tumor Chemotherapy, Molecular Therapeutics, and Immunotherapy. Academic Press, 2018.
- Orkin, Stuart H., David E. Fisher, A. Thomas Look, Samuel Lux, David Ginsburg, and David G. Nathan. Oncology of Infancy and Childhood E-Book. Elsevier Health Sciences, 2009.
- Rodriguez, Fausto J., Andrew L. Folpe, Caterina Giannini, and Arie Perry. “Pathology of Peripheral Nerve Sheath Tumors: Diagnostic Overview and Update on Selected Diagnostic Problems.” Acta Neuropathologica 123, no. 3 (March 2012): 295–319. https://doi.org/10.1007/s00401-012-0954-z.
Image References
- Localized Cutaneous Neurofibromas
- Germany, Klaus D. Peter, Gummersbach. Neurofibroma of the Skin. Patient Suffering from Recklinghausen’s Disease. November 25, 2009. Self-photographed. https://commons.wikimedia.org/wiki/File:Neurofibroma03.jpg.
- Diffuse Cutaneous Neurofibroma
- Nasimudeen, Dr Roshan. English: Diffuse Neurofibroma: The Tumor Is Poorly-Circumscribed and Spreads Laterally along Tissue Planes Causing Plaque-like Thickening of the Skin. March 24, 2017. Department of Pathology, Government Medical College, Kozikode. https://commons.wikimedia.org/wiki/File:Diffuse_neurofibroma.jpg.
- Plexiform Neurofibroma
- Bockenheimer, Ph (Philipp). Atlas of Clinical Surgery; with Special Reference to Diagnosis and Treatment for Practitioners and Students. New York?: Rebman, 1908. http://archive.org/details/atlasofclinicals00bock.
- Schwannoma
- Nasimudeen, Dr Roshan. English: Neural Tumour with Cut End of Nerve Affected by It on Both Ends. March 24, 2017. Department of Pathology, Government Medical College, Kozhikode. https://commons.wikimedia.org/wiki/File:Schwannoma.jpg.