CAP16 Abstract Highlights - Heterotopic Cutaneous Meningioma: An Unusual Presentation Occurring in a Patient With a History of Intracranial Meningioma

The 2016 annual meeting of the College of American Pathlologists (CAP16) is coming up September 25-28 in Las Vegas. I'll be attending the meeting this year. In this series of posts, I'll be featuring poster abstracts of particular interest to neuropathologists.

Chibuike L. Enwereuzo and Jean Henneberry at Baystate Medical Center/Tuft University School of Medicine, in Springfield, Massachusetts  discuss an unusual case of cutaneous meningioma in a patient with a history of intracranial meningioma (Poster #106):

Meningioma is a neoplasm of the meninges and typically occurs in intracranial sites. Extracranial meningioma has been reported most frequently in the sinonasal tract and skull bone, most often as extension of intracranial meningiomas. Isolated heterotopic meningioma without contiguous intracranial lesion is extremely rare. A 56-year-old woman presented in December 2015 with 2 firm subcutaneous scalp masses: one in the left lateral and the other in the left superior regions. The clinical impression was that of lipoma. Pathologic examination revealed
an ill-defined proliferation of fairly uniform meningothelial cells, infiltrating a fibroblastic stroma with interspersed adipose tissue. The 2 excised lesions had similar histologic features. Immunohistochemical stains were performed, and the tumor cells were positive for epithelial membrane antigen and negative for S100. A diagnosis of atypical meningioma, World Health Organization (WHO) grade II, was made. The patient’s medical history was significant for intracranial meningioma of the frontal lobe in October 2007, which was diagnosed as atypical meningioma, WHO grade II. Comparison of the scalp masses to her prior meningioma revealed a distinctly different morphologic pattern. Considering the 8-year interval between the scalp tumors and intracranial meningioma, it is unlikely that her most recent tumors represent a recurrence or metastasis of the intracranial tumor.