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Published on: February 17, 2023
A study of prognostic factors in 45 cases of atypical meningioma
Toshiki Endo1,2, Ayumi Narisawa3, Hosam Shata Mohamed Ali3,4
1Department of Neurosurgery, Tohoku University, Graduate School of Medicine, 1-1 Seiryo Aoba, Sendai, Japan, 980-8574. endo@nsg.med.tohoku.ac.jp.
Background:
Atypical meningioma differs from Grade I meningioma in terms of high recurrence rate and short life expectancy. We evaluated the clinical course of atypical meningioma and investigated prognostic factors affecting its outcomes.
Method:
We reviewed 45 patients with atypical meningioma who underwent surgical intervention between January 2000 and December 2013. The mean age of the patients and mean follow-up period was 58.7 years and 81.0 months, respectively. Analyses included factors such as patient age, gender, location and size of tumor, extent of surgical resection (Simpson Grading System), and MIB-1 labeling index (LI). Univariate analysis was used to detect prognostic factors associated with recurrence and survival.
Results:
The 5-year recurrence-free rate for all 45 patients was 58.4 %; 5- and 10-year survival rates were 83.2 % and 79.9 %, respectively. In univariate analyses, age >60 years, and MIB-1 LI correlated with disease recurrence, whereas age >60 years, subtotal surgical resection, MIB-1 LI, and indication for radiotherapy correlated with death. MIB-1 LI levels higher than 12.8 % and 19.7 % predicted recurrence and death, respectively. In our cohort, 26 patients received postoperative radiotherapy including conventional radiation (n = 21) or gamma knife radiosurgery (n = 5). Postoperative radiotherapy did not decrease recurrence rates in our cohort (p = 0.63). Six and two patients who died during the study period underwent conventional radiation and radiosurgery, respectively.
Conclusions:
Age, male gender, extent of surgical resection, and higher MIB-1 LI influenced the outcome of atypical meningioma. In our cohort, postoperative radiotherapy failed to provide long-term tumor control. Following incomplete surgical resection of atypical meningioma in elderly patients, adjuvant postoperative radiotherapy may not be an ideal treatment option, particularly when MIB-1 LI is higher than 19.7 %.
Insights
Atypical meningioma outcomes are influenced by age, gender, resection extent, and MIB-1 LI. Postoperative radiotherapy did not improve recurrence rates in this study.
Area of Science:
- Neurosurgery
- Oncology
- Pathology
Background:
- Atypical meningioma (WHO Grade II) presents higher recurrence and lower survival rates compared to Grade I meningiomas.
- Understanding prognostic factors is crucial for managing atypical meningioma.
- This study evaluates clinical outcomes and prognostic indicators in atypical meningioma patients.
Purpose of the Study:
- To identify prognostic factors influencing the clinical course of atypical meningioma.
- To assess the impact of surgical resection extent and MIB-1 labeling index (LI) on patient outcomes.
- To evaluate the efficacy of postoperative radiotherapy in atypical meningioma management.
Main Methods:
- Retrospective review of 45 patients with atypical meningioma treated between 2000 and 2013.
- Analysis of patient demographics, tumor characteristics (size, location), extent of surgical resection (Simpson Grading System), and MIB-1 LI.
- Univariate analysis to determine factors associated with recurrence-free survival and overall survival.
Main Results:
- The 5-year recurrence-free rate was 58.4%, with 5- and 10-year survival rates of 83.2% and 79.9%, respectively.
- Age > 60 years, subtotal resection, and MIB-1 LI (>12.8% for recurrence, >19.7% for death) were significant prognostic factors.
- Postoperative radiotherapy, including conventional radiation and gamma knife radiosurgery, did not significantly reduce recurrence rates (p=0.63).
Conclusions:
- Age, male gender, extent of surgical resection, and higher MIB-1 LI significantly impact atypical meningioma outcomes.
- Postoperative radiotherapy demonstrated no long-term tumor control benefit in this patient cohort.
- Adjuvant radiotherapy following incomplete resection in elderly patients with high MIB-1 LI (>19.7%) may not be an optimal strategy.
