The differential diagnosis of dermal nerve sheath myxoma includes acral fibromyxoma, superficial angiomyxoma, soft tissue myoepithelioma, and cellular neurothekeoma
. Acral fibromyxoma has a less myxoid matrix than dermal nerve sheath tumor and is negative for S100 protein.
These include such widespread adult and pediatric cancers as melanoma and neuroblastoma, as well as other less common types of tumors, namely, paraganglioma, pheochromocytoma, schwannoma, esthesioneuroblastoma, malignant peripheral nerve sheath tumors, granular cell tumors, neurofibroma, perineurioma, neurothekeoma
, nerve sheath myxoma, and medullary thyroid cancer .
Besides, the possibly histogenetic link among PFHT and cellular neurothekeoma
has also been documented .
Various other terms also had been used for the dermal neoplasms, such as neurothekeoma
, nerve sheath myxoma, benign myxoid tumor of nerve sheath, perineural myxoma, bizarre cutaneous neurofibroma.1,3 However, some authors consider that the term pacinian perineural cell fibroma may describe it better.2
Other pathological differential diagnoses of our case would include hybrid peripheral nerve sheath tumors, perineurioma, cellular neurothekeoma
, nerve sheath myxoma (classic neurothekeoma
), desmoplastic neurothekeoma
, superficial angiomyxoma (cutaneous myxoma), (16) solitary neurofibroma with prominent differentiation of Meissner bodies, or spindle cell carcinoma.
When they are pigmented they can be misdiagnosed clinically as malignant melanoma, bednar tumor, mycosis fungoides and neurothekeoma
There are 5 entities commonly accepted as myxomas: intramuscular myxoma, juxta articular myxoma, superficial angiomyxoma (or cutaneous myxoma), aggressive angiomyxoma (usually pelvic and perineal regions) and myxoma of nerve sheath (myxoid neurothekeoma
It is notably absent in cellular neurothekeoma
, Langerhans cell histiocytosis, perineurioma, MCC, spindle cell SCC, AFX, and leiomyosarcoma.
Although some morphologically similar lesions lack S100 expression (such as cellular neurothekeoma
), (25) S100 is expressed in a subset of sarcomas and may be expressed in carcinomas, especially those from the breast and salivary gland.
PGP9.5: a marker for cellular neurothekeoma
. Am J Surg Pathol.
To expand the differential diagnosis, some spitzoid lesions may need to be distinguished from cellular neurothekeomas
or histiocytic/fibrohistiocytic lesions.
Of the several antigens detected by anti-S100, A6 is expressed by some melanocytic lesions and is also a very helpful marker to detect neurothekeomas