Meningiomas Adjacent to Major Venous Sinuses-Clinical Outcome and Recurrence

BACKGROUND: Surgical treatment of meningiomas next to venous sinuses is difficult because of their irregular growth patterns and infiltration into the venous sinuses, making gross total resection impossible in some patients. We evaluated the postoperative clinical and neurologic course of this tumor subgroup. METHODS: This study included 141 consecutive patients with meningioma located within 20 mm of a major venous sinus. Complete data sets were available for all patients. We reviewed patient charts and surgical reports for demographics, histology, and clinical and neurologic performance preoperatively and postoperatively and during follow-up. Radiographic images were screened for tumor extension, infiltration into the skull, sinus infiltration (Sindou grade), extent of resection (Simpson grade), and tumor recurrence. RESULTS: Immediate postoperative neurologic improvement was found in 53.7% (n = 36) of patients with preoperative neurologic deficits (n = 67). Follow-up was up to 13.5 years. Medical Research Council Neurological Performance Scale and Karnofsky performance scale postoperatively improved in 24.1% and 55.3% of patients, respectively. Local tumor recurrence was detected in 10.6% (n = 15) of patients. HigherWorld Health Organization grade (P = 0.03), tumor size (P = 0.001), and bone invasion (P = 0.002) were predictors of local tumor recurrence. The median MIB-1 labeling index in patients with tumor recurrence was twice as high as in patients without recurrence. CONCLUSIONS: Surgical removal of meningiomas adjacent to venous sinuses reduces neurologic impairment and enables local tumor control in most patients. Tumor size, bone infiltration, and higher World Health Organization grade are important predictors of tumor recurrence.