Spheno-orbital meningiomas: predictors of recurrence and novel strategies for surgical management.

Abstract

Objective: Spheno-orbital meningiomas (SOMs) represent approximately 2%-9% of tumors affecting the sphenoid wings. The main challenge in treating these meningiomas is achieving gross-total resection (GTR) due to the hyperostosis, which is pathognomonic. This study explored potential correlations between the recurrence rate of SOM and the extent of resection (EOR) of both the bony tumor portion (BTP) and soft tumor portion (STP). Additionally, it analyzed the progression-free survival (PFS) of SOM patients in relation to the EOR, adjuvant treatments, and other recognized risk factors, including demographic, clinical, and radiological characteristics.

Methods: This retrospective study included a consecutive series of patients surgically treated for SOM at a single institution between 2011 and 2021. Demographic and clinical data were gathered from institutional medical records. Preoperative and postoperative brain CT and MRI scans were analyzed, with the STP and BTP identified and segmented based on their radiological characteristics. PFS was assessed using the Kaplan-Meier method, considering treatment options at recurrence (stereotactic radiosurgery [SRS] versus surgery) and applying the Youden index to determine the optimal residual STP volume cutoff.

Results: The study cohort included 89 patients diagnosed with SOM, with a female-to-male ratio of 8.9:1. The average follow-up period was 78 months. Sixty percent of the patients had a history of contraceptive use for more than 10 years. While no significant correlation was found between postoperative BTP volume and recurrence (p > 0.05), a significant correlation was observed for the STP (p < 0.001). The recurrence rate after the initial surgery was 22.5%, with 20% of those patients undergoing a second surgery and 80% treated with SRS. Only 3.4% of patients required three treatments throughout the follow-up. Patients with a postoperative STP volume greater than 3.7 mm3 had an adjusted OR of 1.342 for recurrence risk (p < 0.001) and shorter progression-free survival (p = 0.049).

Conclusions: This study suggests that achieving a safe maximal resection of the STP might help lower the recurrence rate of SOM, whereas this does not appear to apply to the BTP. Overall, the surgical approach for SOM should be tailored to prioritize maximal resection of the STP. Conversely, removal of the BTP should be tailored based on neurological deficits caused by direct compression of the orbit or venous congestion.