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[Relevance of Simpson's grading system for resections in WHO grade I meningiomas]
Alvaro Otero1, María Dolores Tabernero2, María Cristina Muñoz3
1Servicio de Neurocirugía, Complejo Asistencial Universitario de Salamanca, Salamanca, España.
Object:
The aim of this study is to assess if the recurrence rates and recurrence/progression-free survivals (RFS) are different after Simpson's grades I, II, III and IV resections in World Health Organization (WHO) grade I meningiomas.
Material And Methods:
A retrospective review was conducted on the data of patients who underwent surgical treatment of WHO grade I meningiomas located in convexity, falx/parasagittal, and skull base (anterior/media/posterior) between June 1991 and December 2011. In Simpson's grade IV resections, surgical treatment was supplemented with radiotherapy/radiosurgery on the tumour remains. A comparison was made on the recurrence rates and RFSs between Simpson's grades I, II, III, and IV resections, both overall and in tumour subsets according to their location.
Results:
A total of 208 meningiomas were included in this study. There were no significant differences in recurrence rates and RFSs between Simpson's grades I, II, III, and IV. No significant differences were noted between the different degrees of Simpson in any of the location groups. In convexity meningiomas, the recurrence rates were 7% and 33% in Simpson's grades I and III resections, respectively (P=.131).
Conclusions:
It has been shown that the rates of tumour control in meningiomas are not related to Simpson grades. In falx/parasagittal and skull base meningiomas, more aggressive attempts of tumour resection must be balanced against the risks of damaging critical neurovascular structures. In convexity meningiomas, a Simpson's grade I resection should be attempted first.
Insights
Tumor recurrence rates and progression-free survival in World Health Organization (WHO) grade I meningiomas are not significantly different across Simpson resection grades I-IV. Surgical approach should balance extent of resection with neurovascular risks based on tumor location.
Area of Science:
- Neurosurgery
- Oncology
- Pathology
Background:
- Meningiomas are common primary tumors of the central nervous system.
- Surgical resection is the primary treatment for meningiomas.
- Simpson grading classifies the extent of meningioma resection based on visible tumor removal.
Purpose of the Study:
- To evaluate the impact of Simpson's grades I, II, III, and IV resections on recurrence rates and recurrence/progression-free survival (RFS) in World Health Organization (WHO) grade I meningiomas.
Main Methods:
- Retrospective review of 208 patients with WHO grade I meningiomas (convexity, falx/parasagittal, skull base) treated between 1991-2011.
- Simpson grades I-IV resections were analyzed for recurrence rates and RFS.
- Simpson grade IV resections were supplemented with radiotherapy/radiosurgery for residual tumor.
Main Results:
- No significant differences in recurrence rates or RFS were observed between Simpson's grades I, II, III, and IV overall.
- No significant differences were noted across Simpson grades within specific tumor locations.
- Convexity meningiomas showed 7% recurrence for Simpson grade I versus 33% for Simpson grade III (P=.131).
Conclusions:
- Tumor control rates in meningiomas are independent of Simpson resection grades.
- For falx/parasagittal and skull base meningiomas, aggressive resection must be weighed against potential neurovascular damage.
- A Simpson's grade I resection is recommended as the initial approach for convexity meningiomas.
