Department of Pathology at UMMS-Baystate
Diagnosis | Medical Pathology | Neoplasms | Pathological Conditions, Signs and Symptoms | Pathology
Cutaneous (extracranial) meningioma is a rare entity that arises from arachnoid cells. It can be ectopic or metastatic. The incidence of cutaneous meningiomas is 1-2% of all meningiomas. This tumor most commonly occurs on the scalp or along the vertebral axis as a firm, generally painless, subcutaneous nodule, and it invokes a wide clinical differential diagnosis. So, a definitive diagnosis is based on tissue microscopy. This is a rare entity with a broad differential diagnosis on cytology that can pose a diagnostic challenge to a cytopathologist. Literature review revealed few cases reporting the cytology of this tumor and most reported cases are based on conventional cytology smears. We present the cytomorphologic features of an ectopic extracranial meningioma evaluated on a ThinPrep Papanicolaou stain with subsequent histologic correlation.
A 59-year-old male with a past medical history of chronic rhinitis presented with a left forehead, deep subcutaneous, firm, painless mass. The mass measured 2.5 cm and was gradually enlarging. On imaging, the mass was limited to the subcutaneous tissue. On fine needle aspiration cytology, the hypo-cellular aspirate demonstrated polygonal cells arranged in small clusters and single cells with a moderate amount of cytoplasm and bland appearing oval nuclei with intranuclear grooves and pseudo-inclusions. The final diagnosis was epithelioid neoplasm favoring extracranial meningioma. A biopsy for a definitive diagnosis was recommended. Excision biopsy was performed which showed whorls and nests of round to oval cells with pale cytoplasm, indistinct cell borders, and intranuclear cytoplasmic pseudo-inclusions in a background of subcutaneous adipose tissue and collagen. Immunohistochemistry studies showed focal EMA staining, strong and diffuse vimentin staining, and negative S100 staining confirming the morphological diagnosis of cutaneous meningioma.
cutaneous meningioma, cytopathology, ThinPrep Papanicolaou stain
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DOI of Published Version
25th Annual University of Massachusetts Medical School Research Retreat 2020
Alhusseiny AM, Kashikar RM. (2020). ThinPrep Cytopathology of Cutaneous Meningioma with Histologic Correlation. University of Massachusetts Medical School Publications. https://doi.org/10.13028/q6bn-9b12. Retrieved from https://escholarship.umassmed.edu/publications/40
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This work is licensed under a Creative Commons Attribution 4.0 License.