EC Neurology

Intracranial mesenchymal tumor (IMT) is a rare tumor that has recently been identified in children and young adults as a provisional entity with uncertain differentiation. It was previously referred to as the intracranial myxoid variant of angiomatoid fibrous histiocytoma; however, this term is not recommended in the latest World Health Organization (WHO) classification (5^th edition, 2021).

IMT exhibits diverse histological features, including stellate and spindle cell morphology, mucin-rich stroma, hemangioma-like vasculature, and an epithelioid cell pattern with mucin-poor collagenous stroma. The tumor often presents polyphenotypic immunoprofiles, frequently showing positivity for desmin, EMA, and CD99, which can complicate diagnosis.

Due to its rarity, the biological behavior, outcomes, and management remain undefined in the literature.

Herein, we present a new case initially suspected to be a cavernoma based on preoperative imaging. It was misdiagnosed as a meningioma during intraoperative frozen section consultation. This case illustrates the diagnostic challenges encountered in pathological analysis.

 Keywords: Intracranial; Mesenchymal Tumor; Morphology; Pitfalls; Case Report

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