Cavernous Malformation‐Like Vascular Lesion Within an Atypical Meningioma: A Case Report

A case of meningioma that contained a cavernous malformation (CM)-like, anomalous vascular lesion within the tumor is reported. The patient was an 84-year-old man with a convexity meningioma of the left frontal lobe. The tumor showed histopathological features of atypical meningioma suggestive of progression to anaplastic meningioma and contained a well-circumscribed vascular lesion resembling a CM. The pathogenesis of the association of meningiomas with CM-like vascular lesions is briefly discussed, and in the present case the vascular lesion is considered to represent an anomalous reactive proliferation of stromal blood vessels in an atypical meningioma.