Neurology India
Open access journal indexed with Index Medicus
  Users online: 1166  
 Home | Login 
  About Current Issue Archive Ahead of print Search Instructions Online Submission Subscribe Etcetera Contact  
  Navigate Here 
 Search
 
  
 Resource Links
  ╗  Similar in PUBMED
 ╗  Search Pubmed for
 ╗  Search in Google Scholar for
 ╗Related articles
  ╗  Article in PDF (487 KB)
  ╗  Citation Manager
  ╗  Access Statistics
  ╗  Reader Comments
  ╗  Email Alert *
  ╗  Add to My List *
* Registration required (free)  

 
  In this Article
 ╗  Abstract
 ╗ Introduction
 ╗  Materials and Me...
 ╗ Results
 ╗ Discussion
 ╗  References
 ╗  Article Tables

 Article Access Statistics
    Viewed2105    
    Printed64    
    Emailed2    
    PDF Downloaded69    
    Comments [Add]    
    Cited by others 5    

Recommend this journal

 


 
Table of Contents    
ORIGINAL ARTICLE
Year : 2013  |  Volume : 61  |  Issue : 1  |  Page : 40-44

Three risk factors for WHO grade II and III meningiomas: A study of 1737 cases from a single center


Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China

Date of Submission04-Sep-2012
Date of Decision17-Sep-2012
Date of Acceptance23-Jan-2013
Date of Web Publication4-Mar-2013

Correspondence Address:
Shu Jiang
Department of Neurosurgery, West China Hospital, Sichuan University, NO. 37. Guoxue Alley, Chengdu, Sichuan Province, 610041
China
Login to access the Email id

Source of Support: This work was supported by the National Natural Science Foundation of China (Grant No. 81072077) and Foundation of Science and Technology Department of Sichuan Provience (Grant NO.2010SZ0160), Conflict of Interest: None


DOI: 10.4103/0028-3886.107928

Rights and Permissions

 ╗ Abstract 

Background: Meningiomas account for 35.5% of central nervous system (CNS) tumors, of which 21-37.8% are atypical or anaplastic/malignant. High-grade meningiomas have higher rates of recurrence and worse outcome than grade I/II meningiomas. Thus, it is of importance to assess the tumor biology before treatment initiation. Materials and Methods: This study reviewed 1737 patients with histologically confirmed meningioma at a single institution. Meningiomas were classified according to World Health Organization (WHO) 2007 grading and the location of the tumor was confirmed from the operation records and preoperative imaging. Univariate and multivariate logistic regression were used to analyze the potential risk factors for high-grade pathology. Results: Young men and pediatric patients were less likely to have meningioma, but they had high-grade meningioma. Tumors originated from non-skull base and lateral intracranial are more likely to be grade II/III meningioma. Conclusions: Lateral and non-skull base location, male sex, and the younger patients increase the risk for grade II and III pathology. These factors should be considered while deciding treatment choice, surgical resection, and prognosis as well.


Keywords: Benign, location, meningioma, malignant, risk factor


How to cite this article:
Zhou P, Ma W, Yin S, Li Y, Jiang S. Three risk factors for WHO grade II and III meningiomas: A study of 1737 cases from a single center. Neurol India 2013;61:40-4

How to cite this URL:
Zhou P, Ma W, Yin S, Li Y, Jiang S. Three risk factors for WHO grade II and III meningiomas: A study of 1737 cases from a single center. Neurol India [serial online] 2013 [cited 2017 Apr 23];61:40-4. Available from: http://www.neurologyindia.com/text.asp?2013/61/1/40/107928



 ╗ Introduction Top


Meningiomas are the most common intracranial tumor and account for 35.5% of central nervous system (CNS) tumors. [1] About 21-27.8% of meningiomas are World Health Organization (WHO) grade II and III. [2],[3],[4],[5] High-grade tumors have higher risk of recurrence and requires special attention of neurosurgeons. [5],[6],[7] Surgical resection is the standard treatment; however, with wide use of gamma knife surgery (GKS), patients with small lesions and no neurological defects are no longer candidates for surgery. [8],[9],[10] Extensive resection in patients with invasive lesions and lesions in complex anatomical location may be associated with significant postoperative deficits. In patients with small lesions, GKS is chosen as the initial treatment modality, and if they turn out be high-grade tumors, further management becomes difficult. Determining the tumor grade preoperatively may help neurosurgeons plan appropriate surgical planning.

In order to identify high-grade tumors before treatment initiation, many studies have attempted to define the possible predictors suggestive of high-grade meningiomas. [11],[12],[13],[14],[15],[16],[17] Most of these studies suggested meningiomas, other than skull-based meningiomas, have higher risk of being atypical or malignant/anaplastic. The conclusions as regard to other risk factors like age and gender were inconsistent. One of the major limitations of these studies was inadequate patient sample size. The other limiting factor is the lack of uniform classification criteria. This study included a large patient sample from a single center, and WHO guidelines proposed in 2007 were adopted while classifying the meningiomas. [18]


 ╗ Materials and Methods Top


This study was a retrospective review of case records of all patients who underwent neurosurgical intervention for intracranial meningiomas between 2005 and 2010 in the West China Hospital. The data collected included age, gender, radiological findings, location of the meningioma, and histopathological findings. All tumor specimens were reviewed and classified according to the WHO 2007 guidelines. [18] Patients with other intracranial tumor or spinal meningiomas were excluded. For patients with repeated operation, only the first operation was included in the data analysis.

Clinical assessment was performed by one neurosurgeon and then re-checked by another neurosurgeon. The anatomical location was confirmed by radiological records and operation notes. Tumors originating from lateral cerebral convexity, cerebellar convexity, and lateral ventricle were considered lateral, non-skull base tumors; other tumor locations including falx, tentorium, sagittal sinus, fourth ventricle, and pineal region were considered median line of non-skull base tumors; skull-base tumors with lateral locations like sphenoid wing, parasellar, petroclival, jugular petrous, lateral anterior, and middle skull-base, and foramen were considered lateral skull-base tumors; olfactory groove, tuberculum, sella, clinoid, and foramen magnum were considered median line of skull-base tumors.

Statistical analysis

The risk factors were selected for analysis based on prior hypothesis and our clinical findings. Univariate analysis was used to identify covariates that might affect the frequency of grade II/III meningiomas. Risk factors with a significance of P ≤ 0.2 in univariate analysis were included in a stepwise binary logistic regression. We fit the binary logistic regression model (backward stepwise method) to analyze the risk factors. The specific setting of the variables was shown in [Table 1]. The goodness of fit of the regression model was confirmed by a non-significant P value on the Hosmer-Lemeshow test (χ2 =6.859, P =0.552). According to the result of the goodness of fit, we finally set age group as dummy variables instead of continuous variable (P =0.037). Odds ratios on multivariate analysis reflected the odds of having high-grade meningioma. All statistical tests were performed using SPSS 16.0. Probability values of 0.05 or less were considered statistically significant.
Table 1: Anatomical location and histological grade according to the world health organization 2007 classification


Click here to view



 ╗ Results Top


A total of 1737 patients had undergone surgical resection for histologically verified meningioma [Table 2]. The mean age was 50.3 ± 13.2 years (0.5-81 years). Data on anatomical location and histological grade are presented in [Table 1].
Table 2: Clinical characteristics of patients (n=1737)


Click here to view


The results of univariate and multivariate logistic regression analysis are presented in [Table 3] and [Table 4]. Analysis by age showed young patients having increased risk of grade II/III meningiomas. Compared to older (>60 years) patients, grade II/III meningiomas had higher incidence in the age group ≤20 years (OR, 2.36; 95% CI, 1.1-5.2; P =0.033), 21-40 years age group (OR, 1.39; 95% CI, 1.0-1.9; P =0.045), but there was no significant difference in the age group between 41 and 60 years (OR, 0.97; 95% CI, 0.7-1.3; P > 0.05). About half of the pediatric patients had II/III meningiomas (5/11, 45.5%) and 23.1% of patients > 65 years of age had higher-grade meningiomas. Univariate analysis demonstrated increased risk for males for grade II/III meningiomas (34.4% vs. 19.7%, P < 0.001) and the risk was increased two-fold (OR, 2.10; 95% CI, 1.7-2.6; P < 0.001) on the multivariate analysis.
Table 3: Univariate analysis of potential risk factors for grade II/IIImeningiomas


Click here to view
Table 4: Multivariate analysis of risk factors for grade II/III meningiomas


Click here to view


Tumor location was classified into four groups according to their origins into median line of skull-base, lateral skull-base, median line of non-skull base, and lateral non-skull base. Tumors with median line of skull-base had the lowest rate of grade II/III meningiomas (26/202, 12.9%). Compared with tumors located at the median line of skull-base with other locations had increased incidence of high-grade meningiomas. Tumors with lateral non-skull base location had the highest incidence (OR, 2.89; 95% CI, 1.9-4.5; P < 0.001) of grade II/III meningiomas, followed by the location of median line of non-skull base (OR, 2.80; 95% CI, 1.4-5.4; P =0.002) and lateral skull base (OR, 1.72; 95% CI, 1.0-2.8; P =0.032).


 ╗ Discussion Top


Determining factors that can accurately predict grade of meningioma before pathological diagnosis would help neurosurgeons to appropriately balance the risk of surgery and the extent of surgical resection. The strength of our study is large patient sample size from a single centre. We stratified the sample according to the age and anatomical locations. The analysis indicates that male gender, younger age, non-skull base location are significant risk factors for grade II/III pathology.

Our results demonstrated that males conferred about two-fold risk of having grade II/III meningiomas and females had a higher overall incidence of meningiomas. [16],[19],[20] The possible reasons for this male gender association with high-grade meningiomas are still unclear. Various studies suggested that hormone levels, hormone receptor status, and chromosome abnormalities may affect the tendency for high-grade tumors. [21],[22],[23],[24],[25] Some studies have also shown an inverse relationship between progesterone receptor expression level and tumor histological grade and tumor recurrence. [22],[22],[23],[24],[25] The hormone-related molecules may be used as markers to identify low-grade and high-grade meningiomas.

Meningiomas are uncommon in the pediatric age group and the prognosis is poor probably related to the aggressive behavior and high recurrence rate. [26],[27],[28],[29],[30],[31],[32],[33] Most of the earlier literature suggested that the pediatric and adolescent meningiomas are more likely to be high-grade meningiomas. Because of large sample size, we were able to stratify the patients into various age groups. In this study, children had the highest rate of grade II/III meningiomas and young men aged ≤40 years had increased incidence of grade II/III meningiomas (44.8% for aged ≤20 years, 28.9% for aged 21-40 years). The possible reason for this occurrence of age-related grade of meningioma may be embryologic abnormality like genetic mutations. These results suggest that, in young patients, surgical therapy should be considered as the first choice even for tumors <3 cm so that high-grade meningiomas are included. Young patients may benefit more from primary surgical intervention and higher grade resection grade. [29] On the other hand, for the aged patients with small tumor or residual tumor, which is hard to remove, GKS could be applied to control the tumor or avoid the increased surgical morbidity, especially for grade I meningioma. [34],[35]

There have been reports regarding the association between grade of meningioma and anatomical location [11],[12],[13],[14],[15],[16] , the observations were that non-skull base meningiomas have a two- to four-folds increased risk of being grade II/III meningiomas. Our study also confirms these observations. Based on the detailed anatomical stratification, we found that meningiomas with lateral non-skull base location have the highest risk of high-grade pathology, followed by tumors with median line of non-skull base location. Our results further support previous conclusions. Besides, we found that meningiomas with median line of skull-base location have the lowest risk of grade II/III pathology. These observations suggest that surgical resection should be the treatment for the tumors with non-skull base location, especially lateral non-skull base meningiomas. Because of the close proximity to important neurovascular structures; complete surgical resection of the skull-base meningiomas may be associated with significant morbidity. As most meningiomas located at the median line of skull-base are benign (87.1%), high Simpson resection grade is associated with higher rates of surgical morbidity and neurological damage, staged operation can be chosen because of the slow growth of the tumor. [36] GKS could also play an important role in the management of the residual tumor. [37],[38],[39],[40],[41],[42] Although some studies claimed that prior surgery is a risk factor for high-grade meningioma, [16] we believe that it is the high-grade meningioma that leads to reoperation.

In addition, the radiological features and histopathological findings are also important predictions for high-grade meningioma and tumor recurrence. Some authors thought that tumor-brain interface and heterogeneous enhancement on magnetic resonance imaging (MRI) were independent predictive factors for high-grade meningioma and capsular enhancement; tumor margin were also useful in distinguishing high-grade tumors from benign tumors. [17] The pathological findings including high mitotic index, brain invasion, high MIB-1 index, spontaneous necrosis, and macronucleoli may also prompt high-grade meningioma and high risk of recurrence. Most of those factors were related to the proliferation of tumor cells and growing speed. Many molecular markers have been used to evaluate the recurrence-free survival, especially the MIB-1 index, hypoxia-inducible factor-1α, and vascular endothelial growth factor. Those markers could be beneficial for planning tailored optimal follow-up strategies and the associated signal system may be used as the target of targeted therapy. [43],[44]

In conclusion, we found that anatomical location, gender, and age are all independent preoperative risk factors for grade II/III meningioma. Notably, the limitations of our study should be acknowledged. First, this is a retrospective study and only important factors inherent to this study design are analyzed. Second, our department mainly serves patients with large and complex tumors because of its role as the tertiary referral center of southwest China. It is highly possible that our sample may not demographically represent the entire meningioma population.

 
 ╗ References Top

1.Dolecek TA, Propp JM, Stroup NE, Kruchko C. CBTRUS Statistical Report: Primary brain and central nervous system tumors diagnosed in the United States in 2005-2009. Neuro-Oncol 2012;14:v1-v49.  Back to cited text no. 1
[PUBMED]    
2.Modha A, Gutin PH. Diagnosis and treatment of atypical and anaplastic meningiomas: A review. Neurosurgery 2005;57:538-50.  Back to cited text no. 2
[PUBMED]    
3.Sade B, Chahlavi A, Krishnaney A, Nagel S, Choi E, Lee JH. World Health Organization Grades II and III meningiomas are rare in the cranial base and spine. Neurosurgery 2007;61:1194-8.  Back to cited text no. 3
[PUBMED]    
4.Rogers L, Gilbert M, Vogelbaum MA. Intracranial meningiomas of atypical (WHO grade II) histology. J Neurooncol 2010;99:393-405.  Back to cited text no. 4
[PUBMED]    
5.Aghi MK, Carter BS, Cosgrove GR, Ojemann RG, Amin-Hanjani S, Martuza RL, et al. Long-term recurrence rates of atypical meningiomas after gross total resection with or without postoperative adjuvant radiation. Neurosurgery 2009;64:56-60.  Back to cited text no. 5
[PUBMED]    
6.Nakasu S, Fukami T, Jito J, Nozaki K. Recurrence and regrowth of benign meningiomas. Brain Tumor Pathol 2009;26:69-72.  Back to cited text no. 6
[PUBMED]    
7.Yang SY, Park CK, Park SH, Kim DG, Chung YS, Jung HW. Atypical and anaplastic meningiomas: Prognostic implications of clinicopathological features. J Neurol Neurosurg Psychiatry 2008;79:574-80.  Back to cited text no. 7
[PUBMED]    
8.Starke RM, Williams BJ, Hiles C, Nguyen JH, Elsharkawy MY, Sheehan JP. Gamma knife surgery for skull base meningiomas. J Neurosurg 2012;116:588-97.  Back to cited text no. 8
[PUBMED]    
9.Flickinger JC, Kondziolka D, Maitz AH, Lunsford LD. Gamma knife radiosurgery of imaging-diagnosed intracranial meningioma. Int J Radiat Oncol Biol Phys 2003;56:801-6.  Back to cited text no. 9
[PUBMED]    
10.Kondziolka D, Mathieu D, Lunsford LD, Martin JJ, Madhok R, Niranjan A, et al. Radiosurgery as definitive management of intracranial meningiomas. Neurosurgery 2008;62:53-8.  Back to cited text no. 10
[PUBMED]    
11.Durand A, Labrousse F, Jouvet A, Bauchet L, Kalamaridès M, Menei P, et al. WHO grade II and III meningiomas: A study of prognostic factors. J Neurooncol 2009;95:367-75.  Back to cited text no. 11
    
12.Kasuya H, Kubo O, Tanaka M, Amano K, Kato K, Hori T. Clinical and radiological features related to the growth potential of meningioma. Neurosurg Rev 2006;29:293-6.  Back to cited text no. 12
[PUBMED]    
13.McGovern SL, Aldape KD, Munsell MF, Mahajan A, Demonte F, Woo SY. A comparison of World Health Organization tumor grades at recurrence in patients with nonskull base and skull base meningiomas. J Neurosurg 2010;112:925-33.  Back to cited text no. 13
[PUBMED]    
14.Nakasu S, Nakasu Y, Nakajima M, Matsuda M, Handa J. Preoperative identification of meningiomas that are highly likely to recur. J Neurosurg 1999;90:455-62.  Back to cited text no. 14
[PUBMED]    
15.Pasquier D, Bijmolt S, Veninga T, Rezvoy N, Villa S, Krengli M, et al. Atypical and malignant meningioma: Outcome and prognostic factors in 119 irradiated patients. A multicenter, retrospective study of the Rare Cancer Network. Int J Radiat Oncol Biol Phys 2008;71:1388-93.  Back to cited text no. 15
[PUBMED]    
16.Kane AJ, Sughrue ME, Rutkowski MJ, Shangari G, Fang S, McDermott MW, et al. Anatomic location is a risk factor for atypical and malignant meningiomas. Cancer 2011;117:1272-8.  Back to cited text no. 16
[PUBMED]    
17.Kawahara Y, Nakada M, Hayashi Y, Kai Y, Hayashi Y, Uchiyama N, et al. Prediction of high-grade meningioma by preoperative MRI assessment. J Neurooncol 2012;108:147-52.  Back to cited text no. 17
[PUBMED]    
18.Louis DN, Ohgaki H, Wiestler OD, Cavenee WK, Burger PC, Jouvet A, et al. The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol 2007;114:97-109.  Back to cited text no. 18
[PUBMED]    
19.Mahmood A, Caccamo DV, Tomecek FJ, Malik GM. Atypical and malignant meningiomas: A clinicopathological review. Neurosurgery 1993;33:955-63.  Back to cited text no. 19
[PUBMED]    
20.Rohringer M, Sutherland GR, Louw DF, Sima AA. Incidence and clinicopathological features of meningioma. J Neurosurg 1989;71:665-72.  Back to cited text no. 20
[PUBMED]    
21.Tabernero MD, Espinosa AB, Maillo A, Rebelo O, Vera JF, Sayagues JM, et al. Patient gender is associated with distinct patterns of chromosomal abnormalities and sex chromosome linked gene-expression profiles in meningiomas. Oncologist 2007;12:1225-36.  Back to cited text no. 21
[PUBMED]    
22.Wolfsberger S, Doostkam S, Boecher-Schwarz HG, Roessler K, van Trotsenburg M, Hainfellner JA, et al. Progesterone-receptor index in meningiomas: Correlation with clinico-pathological parameters and review of the literature. Neurosurg Rev 2004;27:238-45.  Back to cited text no. 22
[PUBMED]    
23.Abdelzaher E, El-Gendi SM, Yehya A, Gowil AG. Recurrence of benign meningiomas: Predictive value of proliferative index, BCL2, p53, hormonal receptors and HER2 expression. Br J Neurosurg 2011;25:707-13.  Back to cited text no. 23
[PUBMED]    
24.Hsu DW, Efird JT, Hedley-Whyte ET. Progesterone and estrogen receptors in meningiomas: Prognostic considerations. J Neurosurg 1997;86:113-20.  Back to cited text no. 24
[PUBMED]    
25.Tao Y, Liang G, Li Z, Wang Y, Wu A, Wang H, et al. Clinical features and immunohistochemical expression levels of androgen, estrogen, progesterone and Ki-67 receptors in relationship with gross-total resected meningiomas relapse. Br J Neurosurg 2012;26:700-4.  Back to cited text no. 25
[PUBMED]    
26.Thuijs NB, Uitdehaag BM, Van Ouwerkerk WJ, van der Valk P, Vandertop WP, Peerdeman SM. Pediatric meningiomas in The Netherlands 1974-2010: A descriptive epidemiological case study. Childs Nerv Syst 2012;28:1009-15.  Back to cited text no. 26
[PUBMED]    
27.Lakhdar F, Arkha Y, El Ouahabi A, Melhaoui A, Rifi L, Derraz S, et al. Intracranial meningioma in children: Different from adult forms? A series of 21 cases. Neurochirurgie 2010;56:309-14.  Back to cited text no. 27
[PUBMED]    
28.Menon G, Nair S, Sudhir J, Rao BR, Mathew A, Bahuleyan B. Childhood and adolescent meningiomas: A report of 38 cases and review of literature. Acta Neurochir (Wien) 2009;151:239-44.  Back to cited text no. 28
[PUBMED]    
29.Kotecha RS, Pascoe EM, Rushing EJ, Rorke-Adams LB, Zwerdling T, Gao X, et al. Meningiomas in children and adolescents: A meta-analysis of individual patient data. Lancet Oncol 2011;12:1229-39.  Back to cited text no. 29
[PUBMED]    
30.Arivazhagan A, Devi BI, Kolluri SV, Abraham RG, Sampath S, Chandramouli BA. Pediatric intracranial meningiomas-do they differ from their counterparts in adults? Pediatr Neurosurg 2008;44:43-8.  Back to cited text no. 30
    
31.Tufan K, Dogulu F, Kurt G, Emmez H, Ceviker N, Baykaner MK. Intracranial meningiomas of childhood and adolescence. Pediatr Neurosurg 2005;41:1-7.  Back to cited text no. 31
[PUBMED]    
32.Sandberg DI, Edgar MA, Resch L, Rutka JT, Becker LE, Souweidane MM. MIB-1 staining index of pediatric meningiomas. Neurosurgery 2001;48:590-5.  Back to cited text no. 32
[PUBMED]    
33.Baumgartner JE, Sorenson JM. Meningioma in the pediatric population. J Neurooncol 1996;29:223-8.  Back to cited text no. 33
[PUBMED]    
34.Wojcieszynski AP, Ohri N, Andrews DW, Evans JJ, Dicker AP, Werner-Wasik M. Reirradiation of recurrent meningioma. J Clin Neurosci 2012;19:1261-4.  Back to cited text no. 34
[PUBMED]    
35.Konglund A, Rogne SG, Lund-Johansen M, Scheie D, Helseth E, Meling TR. Outcome following surgery for intracranial meningiomas in the aging. Acta Neurol Scand 2012 [Epub ahead of print].  Back to cited text no. 35
    
36.Hashimoto N, Rabo CS, Okita Y, Kinoshita M, Kagawa N, Fujimoto Y, et al. Slower growth of skull base meningiomas compared with non-skull base meningiomas based on volumetric and biological studies. J Neurosurg 2012;116:574-80.  Back to cited text no. 36
[PUBMED]    
37.Starke RM, Williams BJ, Hiles C, Nguyen JH, Elsharkawy MY, Sheehan JP. Gamma knife surgery for skull base meningiomas. J Neurosurg 2012;116:588-97.  Back to cited text no. 37
[PUBMED]    
38.Davidson L, Fishback D, Russin JJ, Weiss MH, Yu C, Pagnini PG, et al. Postoperative Gamma Knife surgery for benign meningiomas of the cranial base. Neurosurg Focus 2007;23:E6.  Back to cited text no. 38
[PUBMED]    
39.Starke RM, Nguyen JH, Rainey J, Williams BJ, Sherman JH, Savage J, et al. Gamma Knife surgery of meningiomas located in the posterior fossa: factors predictive of outcome and remission. J Neurosurg 2011;114:1399-409.  Back to cited text no. 39
[PUBMED]    
40.Starke RM, Williams BJ, Hiles C, Nguyen JH, Elsharkawy MY, Sheehan JP. Gamma knife surgery for skull base meningiomas. J Neurosurg 2012;116:588-97.  Back to cited text no. 40
[PUBMED]    
41.Williams BJ, Yen CP, Starke RM, Basina B, Nguyen J, Rainey J, et al. Gamma Knife surgery for parasellar meningiomas: Long-term results including complications, predictive factors, and progression-free survival. J Neurosurg 2011;114:1571-17.  Back to cited text no. 41
[PUBMED]    
42.Ohba S, Kobayashi M, Horiguchi T, Onozuka S, Yoshida K, Ohira T, et al. Long-term surgical outcome and biological prognostic factors in patients with skull base meningiomas. J Neurosurg 2011;114:1278-87.  Back to cited text no. 42
[PUBMED]    
43.Jensen R, Lee J. Predicting outcomes of patients with intracranial meningiomas using molecular markers of hypoxia, vascularity, and proliferation. Neurosurgery 2012;71:146-56.  Back to cited text no. 43
[PUBMED]    
44.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. J Neurosurg 2012;117:121-8.  Back to cited text no. 44
[PUBMED]    



 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]

This article has been cited by
1 Birth desires and intentions of women diagnosed with a meningioma
Michelle A. Owens,Benjamin M. Craig,Kathleen M. Egan,Damon R. Reed
Journal of Neurosurgery. 2015; 122(5): 1151
[Pubmed] | [DOI]
2 Tissue Engineering Strategies as Tools for Personalized Meningioma Treatment
Letizia Ferroni,Alessandro Della Puppa,Domenico DŠAvella,Maurizio Isola,Renato Scienza,Chiara Gardin,Barbara Zavan
Artificial Organs. 2015; 39(7): E114
[Pubmed] | [DOI]
3 Grade 2 meningioma and radiosurgery
Rabih Aboukais,Fahed Zairi,Jean-Paul Lejeune,Emile Le Rhun,Maximilien Vermandel,Serge Blond,Patrick Devos,Nicolas Reyns
Journal of Neurosurgery. 2015; 122(5): 1157
[Pubmed] | [DOI]
4 Proposal for a new risk stratification classification for meningioma based on patient age, WHO tumor grade, size, localization, and karyotype
P. H. Domingues,P. Sousa,A. Otero,J. M. Goncalves,L. Ruiz,C. de Oliveira,M. C. Lopes,A. Orfao,M. D. Tabernero
Neuro-Oncology. 2014; 16(5): 735
[Pubmed] | [DOI]
5 Long-term survival analysis of atypical meningiomas: survival rates, prognostic factors, operative and radiotherapy treatment
Salah Hammouche,Simon Clark,Alex Hie Lin Wong,Paul Eldridge,Jibril Osman Farah
Acta Neurochirurgica. 2014; 156(8): 1475
[Pubmed] | [DOI]



 

Top
Print this article  Email this article
   
Online since 20th March '04
Published by Wolters Kluwer - Medknow