The histopathological spectrum of cutaneous meningeal heterotopias: clues and pitfalls

Abstract

Histopathological features of cutaneous meningeal heterotopias are various and sometimes misleading. Fibrous lesions should not be misdiagnosed as aplasia cutis. Podoplanin-positive pseudovascular spaces represent the main pitfall and should not be diagnosed as lymphangioma. Correct diagnosis is confirmed by EMA and NSE coexpression within the lesion.

Formation of fibroblastic reticular network in the brain after infection with neurovirulent murine coronavirus

“…5C, D). Arachnoid cells are reportedly podoplaninpositive (Pod + ), 48 just as with FRCs in the lymphoid organs. [45][46][47] However, in our analysis, only part of Zic2 + cells in the meninges was Pod + (Supplemental Fig.…”

Case of rudimentary meningocele in identical twin sisters

“…Several terms have been used to describe rudimentary meningocele, and these include cutaneous meningioma, acoelomic meningeal hamartoma, hamartoma of the scalp with ectopic meningothelial elements, sequestrated meningocele and meningeal heterotopia. [1][2][3][4][5] The developmental mechanism of rudimentary meningocele has not been completely clarified yet. Whether rudimentary meningocele is due to proliferation of meningothelial tissue along cutaneous nerves or a variant of meningocele that has occlusion of connection between the skin and the meningeal space is controversial.…”

“…1 A linkage between rudimentary meningocele and neural tube defect (NTD) has been suggested. [1][2][3] There is a recent evidence for a multisite closure of the neural tube. 1 This explains the most frequent locations of NTD and also the congenital nature and distribution of rudimentary meningocele, which also coincide with those of classic meningoceles.…”

Recurrent nodule on the scalp: a differential diagnosis of a nodule on the scalp

“…Association with sinus pericranii, alopecia or scalp hair tufts is reported. [3][4][5] Other important associations are breast cancer, and type I neurofibromatosis, as it is described in meningiomas. 6 As in our case, it can be misdiagnosed as epidermoid or trichilemmal cyst, dermoid cyst, lipoma or fibroma; thus, a skin biopsy is required to differentiate between them.…”

“…Finally, type III CMH shows spindle-shaped and epithelioid cells in a fibrocollagenous stroma and psammoma bodies, as in intracranial meningiomas. 3 Differential diagnosis must be performed regarding the histological pattern; type I CMH shares some features with angiosarcoma; type II, and occasionally type I CMH, might resemble metastatic carcinoma or melanocytic tumour, requiring in almost all cases immunostains. Meningothelial cells express EMA and vimentin; and are negative for S-100, Melan-A, cytokeratin and vascular markers, such as CD31, CD34, Fac-torVIII.…”