Introduction: The Simpson grading system has played an important role in the surgical resections of meningiomas. This study set out to determine if this grading system predicts meningioma recurrence in a modern cohort of patients with tumors of all World Health Organization (WHO)
Methods: Adult patients who underwent primary, non-biopsy resection of a meningioma at a tertiary care institution between 2007 and 2015 were retrospectively reviewed. Stepwise multivariate proportional hazard analyses were used to identify associations with recurrence following resection. Log-rank analyses were used to compare Kaplan-Meier plots for time to recurrence between each Simpson grade.
Results: Of the 572 patients who met the inclusion criteria, 72 (12.6%) presented with recurrence. The factors associated with recurrence after gross-total resection (Simpson I-III) were non-WHO grade 1 (HR [95 % CI] 6.215 [2.864-12.419], p < .0001) and preoperative neurological deficits (HR [95 % CI] 2.862 [1.512-5.499], p = 0.001). Factors associated with recurrence after subtotal resections (Simpson IV) were African-American patients (HR [95 % CI] 2.776 [1.232-5.890], p = 0.02) and parafalcine location (HR [95 % CI] 3.956 [1.624-8.775], p = 0.004). Notably, the Simpson grading scale was not an independent risk factor for recurrence.
Conclusions: The identification and consideration of the factors associated with recurrence after gross-total or subtotal resections may help guide treatment strategies for patients with meningiomas.
Patient Care: In the past, the Simpson grading system set a precedent for the management of patients who underwent surgery for a meningioma. While the goal is to still remove dural attachments and bony involvement when possible, Simpson grade I resections are not always possible. Patients who possess the factors discovered in our study may be predisposed to recurrence and therefore may warrant closer surveillance imaging and/or adjuvant therapies.
Learning Objectives: By conclusion of this session, participants should be able to: 1) identify the role that Simpson grade can play in meningioma resections and 2) describe risk factors associated with greater risk of recurrence after meningioma resection