Citation, DOI, disclosures and article data
At the time the article was created Khalid Alorabi had no recorded disclosures.View Khalid Alorabi's current disclosures
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The Simpson grade of meningioma resection was described in 1957 and correlated the degree of surgical resection completeness with symptomatic recurrence 1.
- complete removal including resection of the underlying bone and associated dura
- 9% symptomatic recurrence at 10 years
- complete removal and coagulation of dural attachment
- 19% symptomatic recurrence at 10 years
- complete removal without resection of dura or coagulation
- 29% symptomatic recurrence at 10 years
- subtotal resection
- 44% symptomatic recurrence at 10 years
- simple decompression with or without biopsy
- 100% symptomatic recurrence at 10 years (small sample in the original paper)
In the conception of the Simpson grade, it was unclear whether meningiomas were surgically curable tumors, and the grade was created based on the assumption that there is a direct correlation between the degree of resection and recurrence of the tumor 2.
The advent of routine post-operative MRI, molecular classifications of meningiomas, and improvements in surgical techniques have put the validity of the Simpson grading into debate 2. Several recent studies found no difference in recurrence in Simpson grade I-III resections, and there also appears to be variability in recurrence within Simpson grade IV resections 3-4. The location of the tumor (convexity vs skull base vs others) also appears to influence the validity of the Simpson grade 5.
Several other grading systems have been proposed, including the MEGA (Meningioma Group Amsterdam Grading System of Meningioma Removal Based on Postoperative Magnetic Resonance Imaging) scale and the Okudesa-Kobayashi grade; however, these have not been widely validated 6,7.
History and etymology
The Simpson grade was described in 1957 by Australian neurosurgeon Donald Simpson (1927-2017) while he worked at the Royal Adelaide Hospital.
- 1. Simpson D. The recurrence of intracranial meningiomas after surgical treatment. J. Neurol. Neurosurg. Psychiatr. 1957;20 (1): 22-39. J. Neurol. Neurosurg. Psychiatr. (citation) - doi:10.1136/jnnp.20.1.22 - Free text at pubmed - Pubmed citation
- 2. Schwartz T & McDermott M. The Simpson Grade: Abandon the Scale but Preserve the Message. J Neurosurg. 2021;135(2):488-95. doi:10.3171/2020.6.jns201904 - Pubmed
- 3. Sughrue M, Kane A, Shangari G et al. The Relevance of Simpson Grade I and II Resection in Modern Neurosurgical Treatment of World Health Organization Grade I Meningiomas. JNS. 2010;113(5):1029-35. doi:10.3171/2010.3.jns091971 - Pubmed
- 4. Oya S, Kawai K, Nakatomi H, Saito N. Significance of Simpson Grading System in Modern Meningioma Surgery: Integration of the Grade with MIB-1 Labeling Index as a Key to Predict the Recurrence of WHO Grade I Meningiomas. JNS. 2012;117(1):121-8. doi:10.3171/2012.3.jns111945 - Pubmed
- 5. Voß K, Spille D, Sauerland C et al. The Simpson Grading in Meningioma Surgery: Does the Tumor Location Influence the Prognostic Value? J Neurooncol. 2017;133(3):641-51. doi:10.1007/s11060-017-2481-1 - Pubmed
- 6. DeMonte F, Smith H, Al-Mefty O. Outcome of Aggressive Removal of Cavernous Sinus Meningiomas. J Neurosurg. 1994;81(2):245-51. doi:10.3171/jns.1994.81.2.0245 - Pubmed
- 7. Slot K, Verbaan D, Bosscher L, Sanchez E, Vandertop W, Peerdeman S. Agreement Between Extent of Meningioma Resection Based on Surgical Simpson Grade and Based on Postoperative Magnetic Resonance Imaging Findings. World Neurosurg. 2018;111:e856-62. doi:10.1016/j.wneu.2017.12.178 - Pubmed