Neurothekeoma

Neurothekeoma
Other namesBizarre cutaneous neurofibroma, myxoma of nerve sheath, pacinian neurofibroma
Neurothekeoma histology slide
SpecialtyOncology Edit this on Wikidata

A Neurothekeoma (NT) is a type of rare benign cutaneous tumor that usually develops on the head and neck. They often occur in the second and early third decades of life and tend to afflict women more frequently than men.[1] First described by Richard L Gallager and Elson B. Helwig, who proposed the term in order to reflect the presumed origin of the lesion from nerve sheath.[2] Microscopically, the lesions described closely resembled the tumor, "nerve sheath myxoma (NSM)", an entity first described by Harkin and Reed.[3] The latter had, through the years, been variously described as bizarre cutaneous neurofibroma, myxoma of nerve sheath, and pacinian neurofibroma.[4]

Clinically, neurothekeomas present as a solitary nodule of the skin. The most common sites of occurrence are the head and neck and the extremities. The lesions range in size from about 0.5 cm to more than 3 cm. The average patient age is about 25 years, but neurothekeomas may occur at any age. Women are affected about twice often; the male to female ratio is approximately 1:2.[5]

Microscopically, neurothekeoma consists of closely aggregated bundles or fascicles of spindle-shaped cells. The fascicles may or may not have a myxoid background.[6]

Since the time of their first description, it has been reported that neurothekeomas are likely not of nerve sheath origin, as implied by the term.[5] Consequently, neurothekeoma and nerve sheath myxoma are likely not related histogenetically, although they are similar in appearance and in behavior.[5] Based mostly on the quantity of myxoid matrix present, neurothekeomas can have a variety of histologic characteristics, including myxoid, cellular, or mixed-type. The myxoid variety of neurothekeoma has inadvertently included nerve sheath myxoma because to similarity in clinical presentation and histology. However, it appears that the neurothekeoma that Barnhill and Mihm reported in 1990 is a separate and distinct entity from true nerve sheath myxoma.[7] It has been proposed that neurothekeomas are derived from fibrohistiocytic cells rather than the peripheral nerve sheath.[8][9][10][11] Despite having a different histologic appearance, neurothekeomas do not respond with the S100 protein while nerve sheath myxoma do (myxoid, mixed, or cellular).

  1. ^ Barnhill RL, Mihm MC. Cellular neurothekeoma. A distinctive variant of neurothekeoma mimicking nevomelanocytic tumors. Am J Surg Pathol. 1990 Feb;14(2):113-20
  2. ^ Gallager RL, Helwig EB (December 1980). "Neurothekeoma-a benign cutaneous tumor of neural origin". American Journal of Clinical Pathology. 74 (6): 759–764. doi:10.1093/ajcp/74.6.759. PMID 7446487.
  3. ^ Harkin, James C.; Richard J. Reed (1969). Tumors of the Peripheral Nervous System. Armed Forces Institute of Pathology Atlas of Tumor Pathology 2Nd series. Washington, D.C.: Armed Forces Institute of Pathology. Retrieved 2024-05-30.
  4. ^ Pulitzer DR, Reed RJ (October 1985). "Nerve-sheath myxoma (perineurial myxoma)". American Journal of Dermatopathology. 7 (5): 407–421. doi:10.1097/00000372-198510000-00003. PMID 4091218. S2CID 12507923.
  5. ^ a b c Fetsch JF, Laskin WB, Hallman JR, Lupton GP, Miettinen M (July 2007). "Neurothekeoma: an analysis of 178 tumors with detailed immunohistochemical data and long-term patient follow-up information". American Journal of Surgical Pathology. 31 (7): 1103–1114. doi:10.1097/pas.0b013e31802d96af. PMID 17592278. S2CID 13038590.
  6. ^ Reed, Richard J.; Pulitzer, Donald R. (2008), "Chapter 35: Tumors of Neural Tissue", in Elder D; et al. (eds.), Lever's Histopathology of the Skin (Ninth ed.), Philadelphia: Lippincott Raven, ISBN 978-0781773638
  7. ^ Almeida TFA, Verli FD, Dos Santos CRR, Falci SGM, Almeida LY, Almeida LKY, Mesquita ATM, León JE. Multiple Desmoplastic Cellular Neurothekeomas in Child: Report of the First Oral Case and Review of the Literature. Head Neck Pathol. 2018 Mar;12(1):75-81.
  8. ^ Fetsch JF, Laskin WB, Hallman JR, Lupton GP, Miettinen M. Neurothekeoma: an analysis of 178 tumors with detailed immunohistochemical data and long-term patient follow-up information. Am J Surg Pathol. 2007 Jul;31(7):1103-14.
  9. ^ Hornick JL, Fletcher CD. Cellular neurothekeoma: detailed characterization in a series of 133 cases. Am J Surg Pathol. 2007 Mar;31(3):329-40.
  10. ^ Page RN, King R, Mihm MC, Googe PB. Microphthalmia transcription factor and NKI/C3 expression in cellular neurothekeoma. Mod Pathol. 2004 Feb;17(2):230-4.
  11. ^ Yun SJ, Park HS, Lee JB, Kim SJ, Lee SC, Won YH. Myxoid Cellular Neurothekeoma: A New Entity of S100-Negative, CD68-Positive Myxoid Neurothekeoma. Ann Dermatol. 2014 Aug;26(4):510-3.