Indian Journal of Dermatology
CORRESPONDENCE
Year
: 2021  |  Volume : 66  |  Issue : 4  |  Page : 416--419

A Case of Dermal Nerve Sheath Myxoma: A Different Tumor from Cellular Neurothekeoma


Huimin Meng, Cunhuo Jiang 
 Department of Dermatology, The Second People's Hospital of Chengdu, Chengdu 610000, Sichuan, China

Correspondence Address:
Huimin Meng
Department of Dermatology, The Second People's Hospital of Chengdu, Chengdu 610000, Sichuan
China




How to cite this article:
Meng H, Jiang C. A Case of Dermal Nerve Sheath Myxoma: A Different Tumor from Cellular Neurothekeoma.Indian J Dermatol 2021;66:416-419


How to cite this URL:
Meng H, Jiang C. A Case of Dermal Nerve Sheath Myxoma: A Different Tumor from Cellular Neurothekeoma. Indian J Dermatol [serial online] 2021 [cited 2023 Feb 7 ];66:416-419
Available from: https://www.e-ijd.org/text.asp?2021/66/4/416/326109


Full Text



Sir,

A 28-year-old Chinese female presented with a 10-year history of a nodule on her left palm [Figure 1], which was slow-growing. In the previous 3 months, the nodule had presented with tenderness. She denied drainage or bleeding. No previous history of trauma, insect bites, or scarring to the area was elicited.{Figure 1}

Physical examination revealed a 1 cm nodule of skin color on the left palm with tenderness, which was firm, nonmobile, and irregular margin.

Complete excision and microscopic examination were performed, showing multiple well-defined various sized lobules separated by fibrous septa in the dermis [Figure 2]. The lobules consisted of large amounts of myxoid matrix and a few scattered spindled stellate cells [Figure 3]. No atypical cells or mitotic figures were seen. Immunohistochemical analyses were positive for S100 protein and vimentin. Ki-67 labeling index was <5%, but negative for glial fibrillary acidic protein (GFAP), CD 34, CD10, Carcinoembryonic antigen (CEA), and Pan cytokeratin (PCK) [Figure 4]. A diagnosis of a dermal nerve sheath myxoma (DNSM) was established [Figure 5],[Figure 6],[Figure 7]. The patient was reviewed 11 months later with no evidence of recurrence.{Figure 2}{Figure 3}{Figure 4}{Figure 5}{Figure 6}{Figure 7}

The first nerve sheath myxoma was reported in the literature by Harkin and Reed in 1969, which originated from the peripheral nerve sheath.[1] And the term neurothekeoma (NT) was introduced in 1980 by Gallager and Helwig.[2] With the increasing number of recent immunohistochemical and ultrastructural reports, the data indicate that NSM exhibits true nerve sheath differentiation, whereas no such compelling evidence exists for cell neurothekeomas (CNT). More evidence shows that NSM is different from CNT by histogenesis, morphology, and immunophenotype.

NSM present with solitary, superficial, multinodular masses in the 0.5–2.5 cm size range, a peak incidence in the third and fourth decades of life,[3],[4] and an anatomic distribution that most of them (86%) occurred in the extremities,[4] no gender difference. CNT also occur as pink erythematous, dome-shaped, solitary, asymptomatic papule, mostly during the second and third decades of life, demonstrating a female predominance (1:1.8).[5] The tumors mostly arise on the upper extremities and head and neck.[5] The mean tumor size is 1 cm, and 90% are smaller than 2 cm.[5],[6]

NSM present as well-circumscribed, non-encapsulated, lobulated lesions, exhibiting proliferation of spindle, stellate, and occasionally epithelioid-shaped cells in an abundant myxoid stroma.[4] Meanwhile, no mitosis or necrosis was evident in the lobular.[4] CNT topically had spindled and epithelioid mononuclear neoplastic cells with relatively abundant cytoplasm;[6] most cases were poorly marginated.[5] The majority of CNT also had occasional multinucleated tumor cells. The tumor cells had a strong tendency for whorled growth, and oftentimes, focal fascicular growth was also present. Nuclear atypia and mitosis were common.[5],[6]

NSM was immunoreactive for S100 protein (100%[3]), often positive for GFAP and CD57,[3],[4] and negative for A melanoma monoclonal antibody (NKI)/C3. CNT was positive for NKI/C3 (100%), Neuro-specific enolase (NSE) (89%), CD10, Mit-F, CD68, α-(Smooth muscle actin) SMA, but negative for S100 protein, GFAP, Melan-A, and CD34.[5],[6],[7]

Other histological differential diagnoses of nerve sheath myxoma include myxoid neurofibroma (MN), perineurioma, and superficial acral fibromyxoma. MN typically has collagen bundles within the myxoid stroma, is not mitotic, and lacks a lobular structure.[8] The tumors consisted of interlacing bundles of Schwann cells, which of the nucleus' apex is slightly curved, comma-like, or wavy. They show patchy S100 (Schwann cells) and CD34 (fibroblast) expression simultaneously.[9] Perineuriomas show a whorled fascicular pattern in a myxoid or collagenous stroma. They can be differentiated from NSM on immunohistochemistry as perineuriomas show strong positivity for EMA and are negative for S100, GFAP, and CD34.[10] Superficial acral fibromyxoma is composed of stellate and spindle-shaped fibroblast-like tumor cells with storiform and fascicular or random growth patterns in a variable degree of admixed myxoid or collagenous matrix with lobular pushing or infiltrative margin in the dermis. There is also blood vessel proliferation, and mast cells are present throughout the dermis with mild nuclear atypia. Tumor cells show positivity for CD34, CD99, vimentin, but EMA results are inconsistent.[11]

Surgical excision was the most common treatment for NSM. NSM has a relatively high local recurrence rate (57%)[4] than the local recurrence rate (7.3–7.5%) in CNT.[5],[6]

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Harkin JC, Reed RJ. Solitary benign nerve sheath tumors. Atlas of Tumor Pathology. Washington DC, USA: Armed Forces Institute of Pathology; 1969. p. 29-51.
2Gallager RL, Helwig EB. Neurothekeoma-A benign cutaneous tumor of neural origin. Am J Clin Pathol 1980;74:759-64.
3Kim BW, Won CH, Chang SE, Lee MW. A case of nerve sheath myxoma on finger. Indian J Dermatol 2014;59:99-101.
4Fetsch JF, Laskin WB, Miettinen M. Nerve sheath myxoma: A clinicopathologic and immunohistochemical analysis of 57 morphologically distinctive, S-100 protein- and GFAP-positive, myxoid peripheral nerve sheath tumors with a predilection for the extremities and a high local recurrence rate. Am J Surg Pathol 2005;29:1615-24.
5Hornick JL, Fletcher CD. Cellular neurothekeoma: Detailed characterization in a series of 133 cases. Am J Surg Pathol 2007;31:329-40.
6Fetsch 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;31:1103-14.
7Kao EY, Kernig ML. Neurothekeoma. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019 Jan17.
8Kane PM, Gaspar MP, Rekant MS. Solitary myxoid neuro fibroma of the palm. J Hand Microsurg 2015;7:330-1.
9da Costa MD, Hoshino K, Stavale JN, Lanzoni OP, Cavalheiro S, Paiva Neto MA. Unusual intracerebral presentation of a myxoid neurofibroma. World Neurosurg 2017;100:713.e5-8.
10Yadav SK, Singh S, Sarin N, Naeem R, Pruthi SK. Nerve sheath myxoma of scalp: A rare site of presentation. Int J Trichology 2019;11:34-7.
11Ramya C, Nayak C, Tambe S. Superficial acral fibromyxoma. Indian J Dermatol 2016;61:457-9.