Novel Findings in a Case Series of Falcine Meningiomas: Experience with 115 Patients

Introduction: Falcine meningiomas represent up to 10% of all intracranial meningiomas, however they have not been a common subject of study in the meningioma literature. Falcine meningiomas have be further characterized by their site of origin on the falx and divided into three groups. A review of the senior author's surgical experience at multiple institutions between 1982–2013 yielded one hundred fifteen falcine meningiomas. The patient group was restricted to patients who had intraoperative findings consistent with falcine origin of the tumor. The cohort demographics, pathologic and radiographic characteristics and long-term postoperative outcomes were studied and described here.

Results: In this series, female patients were more common: of the 115 patients treated 44 were male and 70 female. The mean follow-up period was 63 months. A majority (42%) of the tumors involved the anterior third of the falx and the superior sagittal sinus(SSS) was patient in 64% of patients. A majority (77%) of patients had WHO Grade I tumors, however, male patients were more likely to have WHO Grade II or III compared with females. All male patients had a dural tail, as compared with 82% of female patients. Extent of resection did not appear to be related to site of origin along the falx or involvement of the SSS. Gross total resection was achieved in 84% of patients. There was a 34% recurrence rate; 69% of these underwent reoperation. Multivariate analysis revealed that male gender, subtotal resection and not excising falx beyond the tumor were all independent risk factors for recurrence.

Discussion: The existing literature on falcine meningiomas is currently limited. The senior author's case series demonstrates some findings within these tumors that will hopefully inform their surgical management. The outcome data suggest that extent of resection beyond the tumor and dural tail are important determinants of recurrence. Representative cases will be presented that demonstrate pathologic presence of atypical cells within the falx, over a centimeter beyond the tumor site. These findings advocate for aggressive resection of the falcine dura far beyond the tumor margin. Further studies are certainly needed to determine if these findings are common among falcine meningiomas or are gender-specific.