Intraoral nerve sheath myxoma: Case report and systematic review of the literature

Abstract

Oral NSM is rare and may represent a diagnostic challenge for pathologists. To confirm the diagnosis of NSM, the evaluation of S-100 protein expression or other neural marker is essential. The use of the terms NSM and neurothekeoma as synonymous or as variants of the same tumor should be avoided, because they are clearly distinct lesions.

Oral nerve sheath myxoma: a rare and unusual intraoral neoplasm

“…They found no cases of positive expression of desmin ( n = 8), smooth muscle actin ( n = 5), epithelial membrane antigen ( n = 4), or AE1/AE3 ( n = 3) . Other histologic differential diagnosis includes plexiform neurofibroma and plexiform schwannoma with myxoid change . The histopathological features noted in our case were consistent with a NSM, and diagnosis was confirmed by the positive immunoreactivity with S100.…”

“…The etiology of NSM is unknown, although as many occur in areas subject to trauma, it has been proposed that traumatic injury may play a role . Aside from fibroepithelial polyps, differential diagnosis may include a mucocele, lipoma, fibrolipoma, schwannoma, and a neurofibroma .…”

“…Aside from fibroepithelial polyps, differential diagnosis may include a mucocele, lipoma, fibrolipoma, schwannoma, and a neurofibroma . Histologically, the primary differential diagnosis is a neurothekeoma, which may clinically be indistinguishable from a NSM . Nerve sheath myxomas present as well‐circumscribed, nonencapsulated, lobulated lesions, exhibiting proliferation of spindle, stellate, and occasionally epithelioid‐shaped cells in an abundant myxoid stroma .…”

“…Nerve sheath myxomas present as well‐circumscribed, nonencapsulated, lobulated lesions, exhibiting proliferation of spindle, stellate, and occasionally epithelioid‐shaped cells in an abundant myxoid stroma . Mast cells are frequently seen . In general, less cellularity and larger degree of myxomatous change differentiates a NSM from a neurothekeoma, particularly the cellular variant, in which the tumor cells are characterized by hyperchromatic nuclei and high mitotic counts .…”

An unusual case of neurothekeoma of the arm in an adult

“…This tumor usually involves dermis or, less frequently, mucosal or submucosal tissue and, typically, is described as a small, solitary, slow growing and reddish to flesh-colored nodule or papule [3]. Neurothekeoma preferentially affects the central aspect of the face, the arms or shoulders of women in the second and third decades of life [4, 5]. To the best of our knowledge, this is the first case report of neurothekeoma involving the wrist developing from synovial tissue and with uncertain clinical behavior in an adult female.…”