Synopsis

 well-circumscribed masses
 thick collagen
 small, epithelioid cells exhibiting corded, trabecular and whorled growth patterns
 spindle cells with wavy nuclei end elongated cytoplasmic processes
 dense collagen stroma
 focal whorling formation

Histogenesis

 perineurial cells

Immunochemistry

 EMA + (epithelial membrane antigen +) (#12836021#)
 GLUT1 + (#12836021#)
 CD99 +
 vimentin +
 collagen type IV +
 CD10 +
 S-100 -
 smooth muscle actin - (SMA -)
 CD34 -
 cytokeratin - AE1-3-
 CD57 -

Epidemiology

 children and young adults
 dermal or subcutaneous nodules in the hands or palms
 rarely bilateral (#11841380#)

Predisposition

 neurofibromatosis type 2 (NF2)

Cytogenetics

 46XX,del(10)(q22q24),der(10),del(22)(q11-12q?)/47, idem,+der(10)
 46,XY,t(2;10)(p23;q24) (#16096405#)
 47,XX,add(3)(q23),add(6)(q21),-5,-9,-10,-22,+mar1,+mar2,+mars (#16096405#)

Target regions

 2p23
 10q22-10q24

Molecular biology

 mutations in the NF2 gene (#11290539#, #10403310#)

References

 Yamaguchi U, Hasegawa T, Hirose T, Fugo K, Mitsuhashi T, Shimizu M, Kawai A, Ito Y, Chuman H, Beppu Y. Sclerosing perineurioma: a clinicopathological study of five cases and diagnostic utility of immunohistochemical staining for GLUT1. Virchows Arch. 2003 Aug;443(2):159-63. Epub 2003 Jun 26. PMID: #12836021#

 Balarezo FS, Muller RC, Weiss RG, Brown T, Knibbs D, Joshi VV. Soft tissue perineuromas in children: report of three cases and review of the literature. Pediatr Dev Pathol. 2003 Mar-Apr;6(2):137-41. Epub 2003 Jan 28. PMID: #12545405#

 Fetsch JF, Miettinen M. Sclerosing perineurioma: a clinicopathologic study of 19 cases of a distinctive soft tissue lesion with a predilection for the fingers and palms of young adults. Am J Surg Pathol. 1997 Dec;21(12):1433-42. PMID: #9414186#