Clinical features and treatment of intracranial chordoid meningioma: a report of 30 cases.

AIMS: To discuss the clinical characteristics and prognosis of chordoid meningioma (CM). METHODS AND RESULTS: Tumour samples of CM from 30 patients were re-examined. The postoperative outcomes were analyzed on the basis of clinical observations. The survival probabilities were calculated using the Kaplan-Meier method. Thirty-two operations were performed in 30 cases, including 27 operations for total removal and five operations for subtotal removal. The median follow-up period was 34.0 months. Tumour recurred in five patients, with a median recurrence time of 32.0 months. No systemic manifestations of Castleman's syndrome were found. The majority (80%) of tumours were found in the supratentorial compartments. The MIB-1 labelling index (MIB-1 LI) varied from 1% to 10%. In univariate analyses, the presence of aggressive factors (P = 0.001) and the extent of resection (P = 0.037) were related to progression-free survival (PFS). The MIB-1 LI (P = 0.50) and postoperative radiotherapy (P = 0.62) were not related to PFS. CONCLUSIONS: Chordoid meningioma is a rare subtype of meningioma, and is often found supratentorially. There is an absence of association with Castleman's syndrome. Aggressive factors and the extent of resection are helpful in predicting recurrence. It might be more pertinent to downgrade CM to grade I, unless it shows aggressive factors.