Cutaneous meningioma: a potential diagnostic pitfall in p63 positive cutaneous neoplasms

Abstract

Cutaneous meningiomas are divided into three groups. Type I lesions present at birth and are derived from ectopic arachnoid cells. Type II lesions usually present in adults and are derived from arachnoid cells surrounding nerve bundles. Type III lesions are due to direct extension or metastasis from dural-based neoplasms. Dural-based meningiomas are known to express p63. The aim of our study is to examine the expression of p63 in type II and type III meningioma. Two cases of cutaneous meningioma (type II and type III) were evaluated for the expression of p63, EMA, CK 5/6, S100 and CD31. The cells of interest were spindled to epithelioid and arranged in a whorling pattern. Immunohistochemical staining showed expression of EMA and p63 in both cases, while stains for CK 5/6, S100 and CD31 were negative. Among cutaneous tumors, p63 is considered a marker of epithelial derivation, as it is positive in epidermal and adnexal neoplasms. It is important to be aware of p63 expression in the context of cutaneous meningioma to avoid misinterpretation as an epithelial tumor. On the basis of our small study, it is unlikely that p63 expression would be helpful in distinguishing between type II and type III meningioma, as both may be p63-positive.

Expression of Mesothelioma-Related Markers in Meningiomas: An Immunohistochemical Study

“…Fox et al [37] have reported negative Keratin 5/6 expression in two cases of ectopic cutaneous meningiomas.…”

Type III cutaneous atypical meningioma of the scalp

“…Both types I and II lesions are thought to represent hamartomas and carry significant histopathologic overlap 7 . Type III lesions arise from either direct extension or metastasis from an intracranial meningioma 8 …”

“…7 Type III lesions arise from either direct extension or metastasis from an intracranial meningioma. 8 F I G U R E 2 Coronal section of magnetic resonance imaging showing a type III cutaneous atypical meningioma of the scalp Histopathologically, type I lesions are typically located in the deep dermis and are composed of pseudovascular clefts, which may be lined by scattered eosinophilic epithelioid meningothelial cells with minimal to no atypia in a collagenous nodule. They may also present with a cystic channel or with well-circumscribed nodules.…”

Atypical Presentation of Transcranial Extension of Intracranial Meningiomas

“…Owing to the similar results from immunohistochemical staining of type II and III meningiomas, imaging involving a combination of x-ray and MRI or CT and MRI was performed to appropriately classify the tumors. 27,37,38,[40][41][42][43] Based on our findings, both x-rays and CTs were unable to show the presence of intracranial exchange, resulting in MRIs being the recommended imaging technique to determine whether a lesion is dural based. 37,38,41…”

“…The broad differential diagnosis when evaluating lesions of the head/scalp area can make it difficult to identify cutaneous meningiomas. 37,38 The clinical presentation of firm, subcutaneous nodules normally associated with cutaneous meningiomas is similar to that of a lipoma, trichilemmal cyst, basal cell carcinoma, squamous cell carcinoma, Merkel cell carcinoma, or metastasis of another tumor. 38,39 As a result, all the cases in Table 1 conducted a histological examination with the aid of immunohistochemistry because histopathological findings by themselves are nonspecific.…”