Clinical features, radiological findings, and treatment outcomes of high-grade lateral ventricular meningiomas: a report of 26 cases.

High-grade meningiomas in ventricles are rare, where most published series only include a few patients. A retrospective analysis was performed on the clinical features, radiological findings, and treatment outcomes of 26 patients with high-grade meningiomas in lateral ventricles who were surgically treated in our hospital between July 2008 and July 2016. A female predilection (female/male = 1.4:1) was observed with a mean age of 42.4 years. Headache and/or vomiting (65.3%) were the most common initial symptom, and with symptom duration time ranging between 7 days and 5 years (mean 8.5 months). The lateral ventricle trigone area was the most common site (80.7%). Twenty-two patients (84.6%) obtained gross total resection. The 2007 WHO classification was used to classify 22 (84.6%) meningiomas as grade II and the remaining four tumors were graded III. These tumors accounted for a recurrence rate of 38.5% (10 of 26 patients) and a mortality rate of 11.5% (3 deaths) during the follow-up periods. The recurrence rate after the gross total resection was 27.3% (6 of 22 patients). Radiotherapy was administered as an adjuvant treatment in 12 patients (46.2%) after surgery. There were 4 recurrences out of the 12 patients who received radiotherapy and 6 of the 14 patients relapsed without radiotherapy (p = 0.58). The subtotal resection was considered a risk factor for recurrence. The postoperative radiotherapy seemed to have little significance for the high-grade meningiomas in the lateral ventricles. Long-term follow-up is required, regardless of the resection grade, and reoperation is feasible for patients with recurrence.