Cytology of chordoid meningioma: a series of five cases with emphasis on differential diagnoses

摘要

Background: Chordoid meningioma is a rare meningioma variant characterised by epithelioid cord-likerntumour cells in a myxoid stroma. It is classified as grade II (World Health Organization) tumours, as they haverna tendency to behave more aggressively than traditional meningiomas and have a greater likelihood ofrnrecurrence. Aims: To report the features of intraoperative imprint smears of five cases of chordoid meningioma.rnMethods: The intraoperative squash smears were reviewed for cellularity, cellular atypia, mitotic figure,rncytoplasmic vacuolation, intranuclear inclusion, presence of a cohesive cord of tumour cells, whorl-likernstructure, psammoma bodies, chronic inflammatory cells (lymphocytes and plasma cells), background mucinrnand necrosis. Results: All cases were of moderate to high cellularity, with cohesive cords of bland tumour cells possessingrnuniformly round nuclei with smooth nuclear outline, stippled chromatin and small nucleoli, with cytoplasmicrnvacuolation and chronic inflammatory cells in the background. Intranuclear inclusions (80%) and whorl-likernstructures (60%) were also common. Necrotic background, psammoma bodies or mitotic figures werernconsistently absent. Conclusions: The cytological features of chordoid mengiomas are distinctive, and intraoperative imprintrndiagnosis is feasible.