Neurothekeoma (nerve sheath myxoma)

Neurothekeomas are subdivided into (i) myxoid/hypocellular, (ii) cellular and (iii) mixed subtypes. The mxoid variant shows evidence of neurosustentacular differentiation, while the status of the mixed and cellular variants is less certain.

It has been argued that nerve sheath myxoma is a different entity and should not be classed as a myxoid form of neurothekeoma.

Immunohistochemistry

	myxoid variant	cellular and mixed variants
Nerve growth factor receptor	10/10	0/10
S-100	11/11	1/11
GFAP	10/11	0/10
CD57	5/9	1/7
CD34 (QBend10)	10/10	0/9
Collagen type IV	9/9	9/10
EMA	8/11	1/10
Neurofilament	1/10	1/10
SMA	3/10	5/10
Calponin	4/9	7/9
Factor XIIIa	5/9	7/9

References

WB Laskin et al. The "Neurothekeoma": immunohistochemical analysis distingusihes the true nerve sheath myxoma from its mimics. Hum Pathol 2000;31:1230-1241.

©SMUHT/PW Bishop