Is Falcine Meningioma a Diffuse Disease of the Falx? Case Series and Analysis of a “Grade Zero” Resection

• Published in: Neurosurgery Vol. 87; no. 5; pp. 900 - 909
• Main Authors: Mooney, Michael A, Abolfotoh, Mohammad, Bi, Wenya Linda, Tavanaiepour, Daryoush, Almefty, Rami O, Bassiouni, Hischam, Pravdenkova, Svetlana, Dunn, Ian F, Al-Mefty, Ossama
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01.11.2020; Copyright by the Congress of Neurological Surgeons; Wolters Kluwer Health, Inc
• Subjects: Adult; Aged; Brain cancer; Dura Mater - pathology; Dura Mater - surgery; Female; Humans; Male; Meningeal Neoplasms - mortality; Meningeal Neoplasms - pathology; Meningeal Neoplasms - surgery; Meningioma; Meningioma - mortality; Meningioma - pathology; Meningioma - surgery; Middle Aged; Neoplasm Grading; Neoplasm Recurrence, Local - mortality; Neoplasm Recurrence, Local - pathology; Neoplasm Recurrence, Local - surgery; Neurosurgery; Neurosurgical Procedures - methods; Patients; Progression-Free Survival; Radiation therapy; Retrospective Studies; Sinuses; Surgery; Tumors; Recurrence; Simpson grade; Falx; Meningioma
• ISSN: 0148-396X; 1524-4040; 1524-4040
• DOI: 10.1093/neuros/nyaa038

Abstract BACKGROUND Falcine meningiomas have unique characteristics including their high rates of recurrence, association with high grade pathology, increased male prevalence, and potential for diffuse involvement of the falx. OBJECTIVE To address these issues in a substantial series of falcine meningiomas and report on the impact of extent of resection for this distinct meningioma entity. METHODS Retrospective analysis of characteristics and outcomes of 59 falcine meningioma patients who underwent surgery with the senior author. A “Grade Zero” category was used when an additional resection margin of 2 to 3 cm from the tumor insertion was achieved. RESULTS For de novo falcine meningiomas, gross total resection (GTR) was associated with significantly decreased recurrence incidence compared with subtotal resection (P ≤ .0001). For recurrent falcine meningiomas, median progression-free survival (PFS) was significantly improved for GTR cases (37 mo vs 12 mo; P = .017, hazard ratio (HR) .243 (.077-.774)). “Grade Zero” resection demonstrated excellent durability for both de novo and recurrent cases, and PFS was significantly improved with “Grade Zero” resection for recurrent cases (P = .003, HR 1.544 (1.156-2.062)). The PFS benefit of “Grade Zero” resection did not achieve statistical significance over Simpson grade 1 during the limited follow-up period (mean 2.8 yr) for these groups. CONCLUSION The recurrence of falcine meningiomas is related to the diffuse presence of tumor between the leaflets of the falx. Increased extent of resection including, when possible, a clear margin of falx surrounding the tumor base was associated with the best long-term outcomes in our series, particularly for recurrent tumors.