Recurrences of meningiomas: predictive value of pathological features and hormonal and growth factors

Single versus multiple reoperations for recurrent intracranial meningiomas

PURPOSE

To identify the risk factors and management of the multiple recurrences and reoperations for intracranial meningiomas.

METHODS

Data of a neurosurgical series of 35 patients reoperated on for recurrent intracranial meningiomas were reviewed. Analyzed factors include patient age and sex, tumor location, extent of resection, WHO grade, Ki67-MIB1 and PR expression at initial diagnosis, time to recurrence; pattern of regrowth, extent of resection, WHO grade and Ki67-MIB1 at first recurrence were also analyzed. All these factors were stratified into two groups based on single (Group A) and multiple reoperations (Group B).

RESULTS

Twenty-four patients (69%) belonged to group A and 11 (31%) to group B. The age < 65 years, male sex, incomplete resection at both initial surgery and first reoperation, and multicentric-diffuse pattern of regrowth at first recurrence are risk factors for multiple recurrences and reoperations. In group B, the WHO grade and Ki67-MIB1 increased in further recurrences in 54% and 64%, respectively. The time to recurrence was short in 7 cases (64%), whereas 4 patients (36%) further recurred after many years. Eight patients (73%) are still alive after 7 to 22 years and 2 to 4 reoperations.

CONCLUSION

The extent of resection and the multicentric-diffuse pattern of regrowth at first recurrence are the main risk factors for multiple recurrences and reoperations. Repeated reoperations might be considered even in patients with extensive recurrent tumors before the anaplastic transformation occurs. In such cases, even partial tumor resections followed by radiation therapy may allow long survival in good clinical conditions.

Time to Recurrence of Intracranial Meningiomas from a Monoinstitutional Surgical Series

BACKGROUND

Meningiomas show variable tendency to recur. While risk factors of recurrence have been largely investigated in literature, a paucity of data is available on the time to recurrence. Our purpose was to identify main factors affecting the time to recurrence to assist preoperative treatment decision-making strategy and to define a tailored clinical and neuroradiological follow-up.

METHODS

Data of 35 patients with intracranial meningioma recurrences have been retrospectively reviewed. Demographic (patient age at initial diagnosis and sex), radiologic (meningioma location, pattern of regrowth and topography of recurrences at first reoperation), pathologic (WHO grade and Ki67-MIB1 at initial surgery and at first reoperation, progesterone receptor [PR] expression), and surgical (extent of resection at initial surgery according to Simpsons grading system, number of reoperations) factors were analyzed.

RESULTS

Time to recurrence ranged from 20 to 120 months. Extent of resection at initial surgery was Simpson grade I in 7 patients (20%), grade II in 10 (28.5%), grade III in 14 (40%), and grade IV in 4 (11.5%). Longer median time to recurrence was observed for skull base localization (P < 0.01), Simpson grades I and II versus grades III (P = 0.01) and IV (P = 0.02), values of Ki67-MIB1 ≤ 4% (P = 0.001), and PR > 60% (P = 0.03); conversely, sex, age, number of reoperations, unchanged/progression of Ki67, and/or World Health Organization grade between first surgery and reoperation did not correlate in statistically significant way with time to recurrence.

CONCLUSIONS

The extent of resection and the Ki67-MIB1 represent the most important factors predicting shorter recurrence time of intracranial meningiomas. Patients with incomplete (Simpson grades III and IV) resection and high Ki67-MIB1 values, especially at non-skull base localization and with low PR values, require a closer short-term clinical and radiologic follow-up in the first years after surgery.

A prognostic model for tumor recurrence and progression after meningioma surgery: preselection for further molecular work-up

Purpose

The selection of patients for further therapy after meningioma surgery remains a challenge. Progress has been made in this setting in selecting patients that are more likely to have an aggressive disease course by using molecular tests such as gene panel sequencing and DNA methylation profiling. The aim of this study was to create a preselection tool warranting further molecular work-up.

Methods

All patients undergoing surgery for resection or biopsy of a cranial meningioma from January 2013 until December 2018 at the University Hospital Zurich with available tumor histology were included. Various prospectively collected clinical, radiological, histological and immunohistochemical variables were analyzed and used to train a logistic regression model to predict tumor recurrence or progression. Regression coefficients were used to generate a scoring system grading every patient into low, intermediate, and high-risk group for tumor progression or recurrence.

Results

Out of a total of 13 variables preselected for this study, previous meningioma surgery, Simpson grade, progesterone receptor staining as well as presence of necrosis and patternless growth on histopathological analysis of 378 patients were included into the final model. Discrimination showed an AUC of 0.81 (95% CI 0.73 - 0.88), the model was well-calibrated. Recurrence-free survival was significantly decreased in patients in intermediate and high-risk score groups (p-value < 0.001).

Conclusion

The proposed prediction model showed good discrimination and calibration. This prediction model is based on easily obtainable information and can be used as an adjunct for patient selection for further molecular work-up in a tertiary hospital setting.

Prediction of progesterone receptor expression in high-grade meningioma by using radiomics based on enhanced T1WI

AIM

To predict progesterone receptor (PR) expression of high-grade meningioma using radiomics based on enhanced T1-weighted imaging (WI).

MATERIALS AND METHODS

There were 157 cases of high-grade meningioma in the study. Seventy-eight cases had negative expression and 79 cases had positive expression. Spearman's rank correlation coefficient and least absolute shrinkage and selection operator (LASSO) regression were used to select the valuable features. The models were developed by naive Bayes (NB), random forest (RF), and support vector machine (SVM). Receiver operating characteristic (ROC) and decision curve analysis (DCA) analysis were used to assess the models.

RESULTS

Nine features were selected as the valuable features using Spearman's analysis and LASSO regression. The RF and NB models achieved the same area under the ROC curve (AUC) of 0.75, which was higher than that of SVM (0.74). There was no significant difference among the AUCs of the three models (p>0.05). There was a larger net benefit in the RF model than the SVM and NB models across all threshold probabilities in the DCA analysis.

CONCLUSION

The RF model had good performance in predicting PR expression of high-grade meningioma. PR expression evaluation for high-grade meningioma would be helpful in clinical practice.

Intracranial Meningiomas in Patients Aged ≥80 Years: Pathological Features and Surgical Problems

BACKGROUND

Patients aged >80 years frequently have intracranial meningiomas. In the present study, we have discussed the pathological features, comorbidities, and surgical complications for this age group from a surgical series and literature review.

METHODS

In the present study, we reviewed a surgical series of 354 intracranial meningiomas and compared the oldest age group (age, ≥80 years) of 17 patients with 73 patients aged 70-79 years and 264 patients aged <70 years. From a literature review, we selected 10 studies of meningiomas in patients aged ≥80 years. The analyzed factors included sex, meningioma location, World Health Organization grade, Ki-67 MIB1, progesterone receptor expression, comorbidities, American Society of Anesthesiologists class, Karnofsky performance scale score, postoperative complications, and death.

RESULTS

Patients aged ≥80 years had had higher rates of World Health Organization grade II meningioma, higher rates of Ki-67 expression of >4% and <20%, and progesterone receptor expression <15%. Of the postoperative complications, only neurological deficits and acute bronchopneumonia were significantly more frequent in patients aged ≥80 years. The incidence of intracerebral hematoma, lung embolism, acute heart ischemia, and death were not significantly different between the patients aged ≥80 years and those aged 70-79 years and <70 years.

CONCLUSIONS

Patients aged ≥80 years must be considered a true elderly group with higher rates of comorbidities. The very old age is not a limitation to surgery; however, careful patient selection is necessary. In addition, for the oldest age group, the surgical decision should not be delayed because of advancing age.

Imaging biomarkers associated with extra-axial intracranial tumors: a systematic review

Extra-axial brain tumors are extra-cerebral tumors and are usually benign. The choice of treatment for extra-axial tumors is often dependent on the growth of the tumor, and imaging plays a significant role in monitoring growth and clinical decision-making. This motivates the investigation of imaging biomarkers for these tumors that may be incorporated into clinical workflows to inform treatment decisions. The databases from Pubmed, Web of Science, Embase, and Medline were searched from 1 January 2000 to 7 March 2022, to systematically identify relevant publications in this area. All studies that used an imaging tool and found an association with a growth-related factor, including molecular markers, grade, survival, growth/progression, recurrence, and treatment outcomes, were included in this review. We included 42 studies, comprising 22 studies (50%) of patients with meningioma; 17 studies (38.6%) of patients with pituitary tumors; three studies (6.8%) of patients with vestibular schwannomas; and two studies (4.5%) of patients with solitary fibrous tumors. The included studies were explicitly and narratively analyzed according to tumor type and imaging tool. The risk of bias and concerns regarding applicability were assessed using QUADAS-2. Most studies (41/44) used statistics-based analysis methods, and a small number of studies (3/44) used machine learning. Our review highlights an opportunity for future work to focus on machine learning-based deep feature identification as biomarkers, combining various feature classes such as size, shape, and intensity. Systematic Review Registration: PROSPERO, CRD42022306922.

Molecular diagnosis and treatment of meningiomas: an expert consensus (2022)

ABSTRACT

Meningiomas are the most common primary intracranial neoplasm with diverse pathological types and complicated clinical manifestations. The fifth edition of the WHO Classification of Tumors of the Central Nervous System (WHO CNS5), published in 2021, introduces major changes that advance the role of molecular diagnostics in meningiomas. To follow the revision of WHO CNS5, this expert consensus statement was formed jointly by the Group of Neuro-Oncology, Society of Neurosurgery, Chinese Medical Association together with neuropathologists and evidence-based experts. The consensus provides reference points to integrate key biomarkers into stratification and clinical decision making for meningioma patients.

REGISTRATION

Practice guideline REgistration for transPAREncy (PREPARE), IPGRP-2022CN234.

Progesterone Receptor Expression in Meningiomas: Pathological and Prognostic Implications

Background

The progesterone receptor (PR) is variably expressed in most meningiomas and was found to have prognostic significance. However, the correlation with patient age, tumor location, time to recurrence, and pattern of regrowth has scarcely been discussed.

Methods

A surgical series of 300 patients with meningiomas is reviewed. The PR expression was classified as: 0. absent; 1. low (<15%); 2. moderately low (16-50%); 3. moderately high (51-79%); 4. high (≥80%). The PR values were correlated with the patient age and sex, meningioma location, WHO grade, Ki-67 MIB1, recurrence rate, pattern of recurrence (local-peripheral versus multicentric diffuse), and time to recurrence.

Results

The PR expression has shown lower rate of high expression in the elderly group (p = 0.032) and no sex difference (including premenopausal versus postmenopausal women), higher expression in medial skull base and spinal versus other locations (p = 0.0036), inverse correlation with WHO grade and Ki67-MIB1 (p < 0.0001). Meningiomas which recurred showed at initial surgery higher rates of low or moderately low PR expression than the non-recurrent ones (p = 0.0004), whereas the pattern of regrowth was not significant. Higher rates of PR values ≥80% were found in cases with time to recurrence >5 years (p = 0.036).

Conclusion

The higher PR expression in medial skull base meningiomas, the significant correlation with the time to recurrence, the lack of difference of PR expression between premenopausal and postmenopausal women and between local-peripheral versus multicentric-diffuse recurrences are the most relevant unreported findings of this study. The rate of PR expression must be included in the routine pathological diagnosis of meningiomas because of its prognostic significance.

Intraspinal clear cell meningioma without dural attachment: A case report and literature review

RATIONALE

Clear cell meningioma (CCM) is one of the rarest but most aggressive forms of meningioma, with a tendency to occur at a high recurrence rate. Intraspinal CCM, especially the nondura-based type, is even rarer than the intracranial CCM.

PATIENT CONCERNS

We report a case of a 45-year-old woman who presented with a 1-month history of episodic pain in the lower back and in both thighs in the front side. Femoral nerve stretch tests were positive on both sides. Magnetic resonance imaging (MRI) demonstrated an intradural tumor at the L3 level, which was isointense on T1- and T2-weighted images (WI) and homogeneously enhanced on gadolinium-contrast T1 WI.

DIAGNOSES

The space-occupying lesion was pathologically confirmed as CCM.

INTERVENTIONS

During surgery, we found that the tumor adhered to a nerve root, without dural attachment. The nerve root was partially removed to achieve complete resection.

OUTCOMES

The pain disappeared after the operation. The 1 year follow-up MRI revealed no evidence of tumor recurrence or metastasis.

LESSONS

Nondura-based intraspinal CCM is easier to completely remove, and such complete removal should be achieved during the first operation. Although the recurrence rate of this particular type of meningioma appears to be lower than that of other types, close clinical and radiological follow-up is necessary.

Meningiomas in Premenopausal Women: Role of the Hormone Related Conditions

Background

Several epidemiological and pathological findings suggest that the female sex hormones may influence the development of meningiomas. However, the role of pregnancy, oral contraceptives, and fertilization therapies is still controversial.

Methods

From the surgical series of 354 patients with meningiomas operated between 2006 and 2019, the group of 72 premenopausal women was separately considered. The tumor location, WHO grade, Ki67-labeling index (LI), progesterone receptor (PR) expression, and histological types were studied in premenopausal women with and without hormone-related conditions were compared.

Results

In this premenopausal group, 24 patients had hormone-related conditions, including use of oral contraceptives in 16, intrauterine fertilization in one, pregnancy in three, and tumors of the female reproductive system in four. The group of patients with hormone-related conditions, as compared to that with no hormone related conditions, showed slightly lower median age (38 versus 43 years) and no significant difference of meningioma location WHO grade, Ki 67-Li, PR expression and histological type. The clinical onset during pregnancy in three patients and tumor growth during contraceptive progesterone therapy in two others were evidenced.

Conclusion

The biological behavior of meningiomas and their pathological findings, including PR expression, are not correlated with the different hormone related conditions in premenopausal female patients. Contraceptives and fertilization therapies, mainly with progesterone, should be avoided in patients with meningiomas.

The relationship between vascular endothelial growth factor and histological grade in intracranial meningioma

Background

Meningioma is the most common benign intracranial neoplasm, accounting for 30% of all primary brain tumors. In 90% of cases, meningiomas are benign. Several aspects of molecular biology, including potential biomarkers, have been studied in attempts to better understand the natural history of meningiomas. Vascular endothelial growth factor (VEGF) is a biomarker responsible for inducing physiological and pathological angiogenesis. VEGF expression has been investigated as a potential predictor of several tumor aspects, including growth rate, recurrence rate, brain tissue invasion, peritumoral edema and surgical prognosis, and also as a marker of histological grade. However, there is no consensus in the literature with respect to the association between this biological factor and meningioma. We digitally analyzed immunohistochemical images using ImageJ software with the aim of correlating VEGF expression with tumor histology.

Methods

Tissue samples from patients presenting with meningioma who had undergone surgical removal between 2007 and 2016 at the Hospital de Clínicas de Porto Alegre (HCPA), in Southern Brazil, were analyzed to identify possible immunohistochemical associations between VEGF and histological grade and subtype.

Results

Seventy-six patients were included; 82% were female, mean age was 59.9 years (range: 18-91). No statistically significant associations were found between VEGF expression and histological grade or subtype (P = 0.310).

Conclusion

Our findings suggest that VEGF is frequently present in meningiomas regardless of histological grade and should not be used as a marker of severity or histological grade.

Recurrence/Regrowth in Grade I Meningioma: How to Predict?

The HLA-G and HLA-E molecules, Ki67, progesterone (PR), estrogen (ER) and androgen receptors (AR), p53, COX-2, and HER2 were studied to assess whether the biological behavior of grade I meningiomas is related to their expression. Tissue samples from 96 patients with grade I intracranial meningiomas were analyzed by immunohistochemistry on tissue microarray blocks (TMA) using antibodies specific for HLA-G, HLA-E, Ki67, PR, ER, AR, p53, COX-2, and HER2. Meningiomas were classified as small (≤2 cm, 1.0%), medium (>2 and ≤4 cm, 32.3%), and large (>4 cm, 66.7%). Tumor size was not related to recurrence/regrowth (p = 0.486), but was significantly correlated with peritumoral edema (p = 0.031) and intratumoral calcifications (p = 0.018). Recurrent meningiomas were observed in 14.6% of cases. Immunostaining for each marker was: HLA-G 100%; HLA-E 95.6%; PR 62%; ER 2.1%; AR 6.5%; p53 92.6%; COX-2 100%; HER2 0%; Ki67, mean 2.61 ± 2.29%, median 2.1%. Primary and recurrent meningiomas showed no significant relation with HLA-E and hormone receptors (p > 0.05), except for Ki67, where a higher median was observed in recurrent tumors than in primary (p = 0.014). The larger the tumor, the more severe the peritumoral edema, and the greater the presence of calcifications. Ki67 appears to be a good biomarker of recurrence/regrowth in grade I meningiomas.

Multicentric and diffuse recurrences of meningiomas

Background: Meningiomas recur with a rate of 10-32% at 10 years. Several features influence the risk of recurrence.Objective: To define the pathological and surgical features at risk of multicentric-diffuse versus local-peripheral recurrence.Methods: Thirty-three patients operated on for intracranial meningiomas who experienced multicentric-diffuse recurrence were retrospectively analyzed. The data of these patients were compared to those of 50 patients who experienced local-peripheral recurrence. The analyzed factors included age and sex, tumor location and shape, brain-tumor interface, entity of resection, WHO grade, Ki67 MIB1, progesterone receptor (PR) expression, number of reoperations, progression of WHO grade, and outcome.Results: Meningiomas which recurred in multicentric-diffuse pattern showed at initial surgery a significantly higher rate of flat-shaped tumors (p = .0008) and of cases with Ki67 Li ≥ 4% (p = .037) than those which recurred in localized-peripheral pattern, whereas other factors did not significantly differ. Among patients with multicentric-diffuse recurrences, 25 underwent one to three reoperations; 17 among them (66%) are alive with local tumor control or slow progression 2-25 years after the initial surgery versus only 2 out of 8 who did not undergo surgery.Conclusions: Flat-shaped meningiomas and those with Ki67 Li ≥ 4% are at higher risk of multicentric-diffuse recurrence. Multiple reoperations over a period of several years may obtain rather long survivals in selected patients with prevalent intradural, not anaplastic tumors and not too extensive dural infiltration.

Histopathological Spectrum of Meningiomas with Emphasis on Prognostic Role of Ki67 Labelling Index

BACKGROUND & OBJECTIVE

Meningiomas are the most frequently encountered primary non-glial tumors of the central nervous system (CNS). The Ki67 labelling index (Ki67LI) is a proliferation marker that may prove useful in determining the histological grade. This study aims at: 1) Studying the frequency, grade and histomorphological spectrum of meningiomas, 2) Evaluating 20 histological parameters and determining its utility in grading meningiomas and 3) Comparing the Ki67LI in the various subtypes and WHO grades.

METHODS

The cases of meningiomas diagnosed in our Department from June 2009 to May 2014 were included. The clinical details, grade and 20 histological parameters: mitosis, vesicular nuclei, macronucleoli, nuclear pleomorphism, scattered bizarre nuclei, hypercellularity, sheeting, lymphocytes, small cell change, foam cells, ossification, necrosis, papillary change, lipidization, psammoma bodies, vascularization, brain invasion, dural invasion, bone invasion and other soft tissue invasion were recorded for each case. The average and highest Ki67LI was recorded as percentage and number per high power field.

RESULTS

A total of 175 cases of meningioma were included: grade I (145), grade II (30). Atypical histological features like hypercellularity, sheeting, etc. were common in grade II tumors. Increased vascularity, lymphocytes and psammoma bodies were common in grade I tumors. Ki67LI (highest) ranged from 1-6% in grade I and 5-12% in grade II tumors.

CONCLUSION

Among different methods showing mitotic activity, Ki67% (highest) was the most statistically significant LI in differentiating grade I and grade II tumors. The median Ki67% (highest) was 4% for grade I and 7% for grade II tumors.

Convexity meningioma resection in the modern neurosurgical era

Convexity meningiomas are among the most common extra-axial tumors encountered in neurosurgery. Advances in diagnostic imaging, intraoperative technology, and nonsurgical treatment modalities have changed the face of neurosurgical oncology. In this chapter we describe the modern neurosurgeon's approach to convexity meningiomas in terms of diagnosis, treatment, and follow-up care.

High Mib-1-score correlates with new cranial nerve deficits after surgery for frontal skull base meningioma

Postoperative new cranial nerve deficits comprise severe concomitant morbidity in skull base meningioma surgery. Therefore, long-term cranial nerve integrity represents an important outcome measure. In the current study, we analyzed our institutional database in order to identify risk factors for postoperative new cranial nerve morbidity in the course of frontobasal meningioma surgery. Between 2009 and 2017, 195 patients were surgically treated for frontobasal meningioma at the authors' institution. Postoperative cranial nerve function was assessed immediately after surgery as well as 12 months postoperatively. A univariate and multivariate analysis was performed to identify factors influencing favorable postoperative cranial nerve outcome. Tumors with histological Mib-1-labeling indices > 5% were associated with a significantly higher percentage of new cranial nerve deficits immediately after surgery compared with those with Mib-1-labeling indices ≤ 5% (39% versus 20%, p = 0.029). Elevated Mib-1-labeling indices could be correlated with high CD68-positive macrophage staining (54% for Mib-1 index > 5% versus 19% for Mib-1 index ≤ 5%, p = 0.001). Elevated Mib-1-labeling index correlates with initial new cranial nerve dysfunction after resection of frontal skull base meningioma. With regard to elevated CD68-positive macrophage staining in high Mib-1-positive meningiomas, initial postoperative new cranial nerve morbidity might partly reflect macrophage-based inflammatory immune responses.

WHO grade, proliferation index, and progesterone receptor expression are different according to the location of meningioma

BACKGROUND

Meningiomas may show a different WHO grade and variable biological and clinical behaviors. The aim of the present study is to assess whether WHO grade, proliferation index, progesterone receptor (PR) expression, histological subtype, neuroradiological features, and the recurrence rate differ depending on the tumor location.

METHODS

Three hundred meningiomas operated on from 2006 to 2016 were reviewed. The WHO grade (2007 classification), Ki67-MIB1, progesterone receptor expression, and histological subtype were reexamined and correlated to the meningioma location, classified as medial skull base, lateral skull base, non-skull base, and spinal.

RESULTS

Non-skull base and lateral skull base meningiomas showed significantly higher rates of atypical WHO II forms (34% and 25.5% respectively) than medial skull base (12.5%) and spinal ones (7%) (p = 0.0003) and also higher rates of tumors with Ki67-Li > 4% (42% and 38% vs 22% and 14%) (p = 0.0031). The rate of meningiomas with PR expression ≤ 50% was significantly lower in medial skull base (25%) than in non-skull base (48%) (p = 0.009). Meningothelial and transitional meningiomas were more frequent at the skull base (68.5% and 54.5%, respectively), the fibroblastic subtype at the non-skull base (48.5%), and the psammomatous at the spinal canal (50%) (p < 0.00001). Medial skull base and spinal meningiomas showed significantly lower size (p < 0.00001), lower rates of cases with lost arachnoid interface (p = 0.0022), and significantly lower recurrence rates (p = 0.0035) than lateral skull base and non-skull base meningiomas.

CONCLUSION

Medial skull base meningiomas show lower size, lower rate of atypical forms, lower Ki67-Li values, and significantly higher PR expression than those at the lateral skull base and non-skull base. This corresponds to lesser aggressiveness and lower recurrence rates.

Recurrence of spinal meningiomas: analysis of the risk factors

Objective: Spinal meningiomas are slow-growing tumors with low recurrence rate after complete resection. The aim of this study is to investigate the risk factors correlated to the recurrence.Material and Methods: Six patients with spinal WHO grade I meningiomas which recurred after complete resection were reviewed and compared to 50 patients with no recurrence; the data were also compared with those of 50 intracranial meningiomas which recurred and 50 which did not recur after complete resection. The investigated factors included age and sex, tumor location and size, type of arachnoid interface, entity of resection (Simpson I or II), tumor consistency and vascularity, histological type, Ki-67 MIB-1, progesterone receptor (PR) and estrogen receptor (ER) expression. The data were statistically analyzed with the Kaplan-Meier method.Results: The statistical analysis showed that the presence of arachnoidal invasion (p = 0.023) and higher Ki-67 LI (p < 0.0001) were the only two significant risk factors for recurrence for both spinal and intracranial meningiomas. Large tumor size (p = 0.012), Simpson grade II resection (p = 0.03) and the absence of PR expression (p < 0.0001) were significant risk factors for recurrence of intracranial but not spinal meningiomas. Finally, age and sex, tumor location, consistency and vascularity, histological type, and ER expression were not correlated to recurrence for both localizations.Conclusions: The proliferation index Ki-67 and the arachnoid invasion are the risk factors for recurrence of spinal meningiomas, whereas tumor size, dural resection and PR expression are not significant. The small tumor size and the limited dural invasion may contribute to explain the lower recurrence rate.

Progesterone-only contraception is associated with a shorter progression-free survival in premenopausal women with WHO Grade I meningioma

The hormonally active nature of intracranial meningioma has prompted research examining the risk of tumorigenesis in patients using hormonal contraception. Studies exploring estrogen-only and estrogen/progesterone combination contraceptives have failed to demonstrate a consistent increased risk of meningioma. By contrast, the few trials examining progesterone-only contraceptives have shown higher odds ratios for risk of meningioma. With progesterone-only contraception on the rise, the risk of tumor recurrence with these specific medications warrants closer study. We sought to determine whether progesterone-only contraception increases recurrence rate and decreases progression-free survival in pre-menopausal women with surgically resected WHO Grade I meningioma. Comparative analysis of 67 pre-menopausal women taking hormone-based contraceptives (progesterone-only medication, n = 21; estrogen-only or estrogen/progesterone combination medication, n = 46) who underwent surgical resection of WHO Grade I intracranial meningioma was performed. Differences in demographics, degree of resection, adjuvant therapy and time to recurrence were compared between the two groups. Compared to patients taking combination or estrogen-only contraception, those taking progesterone-only contraception demonstrated a greater recurrence rate (33.3 vs. 19.6%) with a reduced time to recurrence (18 vs. 32 months, p = 0.038) despite a significantly shorter follow-up (p = 0.014). There were no significant demographic or treatment related differences. The results from this study suggest that exogenous progesterone-only medications may represent a specific contraceptive subgroup that should be avoided in patients with meningioma.

Meningioma in Breast Cancer Patients: Population-based Analysis of Clinicopathologic Characteristics

OBJECTIVES

Although an association between meningioma and breast cancer (BC) has been postulated, clear mechanisms remain obscure. By conducting population-based analyses in women with both BC and meningioma, hypothesis-generating causal links were pursued.

METHODS

Using the US SEER 18 registry (2004 to 2009), clinicopathologic and demographic characteristics from cohorts of women with only BC (n=279,821) or meningioma (n=19,570) diagnoses were compared with 412 women with both diagnoses (BC-meningioma).

RESULTS

BC diagnosis preceded meningioma by >2 months in 48% of women; 20% had synchronous (within 2 mo) disease. Median meningioma size was 1.9 and 2.4 cm in the BC-meningioma and meningioma cohorts, respectively (P=0.0009). Among BC-meningioma patients, meningioma size was similar whether diagnosed >2 months prior, synchronously, or >2 months after BC. Meningioma was pathologically confirmed in 38% of BC-meningioma and 51% of meningioma patients. Distribution of BC histologies was comparable in patients with and without meningioma, with ductal type predominating (80% in BC-meningioma, 83% in BC). Although hormone receptor status of invasive BC was not significantly different between BC-meningioma and BC groups, the BC-meningioma cohort had fewer women with ER+/PR+ in situ disease (P=0.006). BC stage among women with meningioma was more advanced versus women with BC only.

CONCLUSIONS

Women with BC and meningioma have smaller-sized meningiomas and more advanced BCs compared with women having only 1 diagnosis. As there was no temporal relationship between size and latency between tumor diagnoses, the disparity in meningioma size between BC-meningioma and meningioma cohorts may have BC-associated biological components that warrant further study.

Expression and clinical value of EGFR in human meningiomas

Background

Meningiomas are common intracranial tumors in humans that frequently recur despite having a predominantly benign nature. Even though these tumors have been shown to commonly express EGFR/c-erbB1 (epidermal growth factor receptor), results from previous studies are uncertain regarding the expression of either intracellular or extracellular domains, cellular localization, activation state, relations to malignancy grade, and prognosis.

Aims

This study was designed to investigate the expression of the intracellular and extracellular domains of EGFR and of the activated receptor as well as its ligands EGF and TGFα in a large series of meningiomas with long follow-up data, and investigate if there exists an association between antibody expression and clinical and histological data.

Methods

A series of 186 meningiomas consecutively operated within a 10-year period was included. Tissue microarrays were constructed and immunohistochemically analyzed with antibodies targeting intracellular and extracellular domains of EGFR, phosphorylated receptor, and EGF and TGFα. Expression levels were recorded as a staining index (SI).

Results

Positive immunoreactivity was observed for all antibodies in most cases. There was in general high SIs for the intracellular domain of EGFR, phosphorylated EGFR, EGF, and TGFα but lower for the extracellular domain. Normal meninges were negative for all antibodies. Higher SIs for the phosphorylated EGFR were observed in grade II tumors compared with grade I (p = 0.018). Survival or recurrence was significantly decreased in the time to recurrence analysis (TTR) with high SI-scores of the extracellular domain in a univariable survival analysis (HR 1.152, CI (1.036–1.280, p = 0.009)). This was not significant in a multivariable analysis. Expression of the other antigens did not affect survival.

Conclusion

EGFR is overexpressed and in an activated state in human meningiomas. High levels of ligands also support this growth factor receptor system to be involved in meningioma tumorigenesis. EGFR may be a potential candidate for targeted therapy.

The correlation of clinical and chromosomal alterations of benign meningiomas and their recurrences

Meningiomas (MGs) are the frequent benign intracranial tumors. Their complete removal does not always guarantee relapse-free survival. Recurrence-associated chromosomal anomalies in MGs haves been proposed as prognostic factors in addition to the World Health Organisation (WHO) grading, tumor size and resection rate. The aim of this study was to evaluate the frequency of deletions on chromosomes in sporadic MGs and to correlate them with the clinical findings and tumor behaviour. Along with survival, the tumor recurrence was the main endpoint. Chromosomal loss of heterozygosity (LOH) was studied. 46 benign MGs were subjected to the analysis, complete tumor resection was intended and no early mortalities were observed. Incomplete removal was related to parasagittal location and psammomatous hisptopathology (p<0.01). Chromosomal alterations were present in 82.6% of cases; LOH at 22q (67.4%) and 1p (34.8%) were the most frequent and associated with male sex (p=0.04). Molecular findings were not specific for any of the histopathologic grade. Tumor recurrence (14 of 46) correlated with tumor size (≥35mm), LOH at 1p, 14q, coexistence of LOH at 1p/14q, 10q/14q, 'complex karyotype' status (≥2 LOHs excluding 22q), patient age (younger <35), and Simpson grading of resection rate (≥3 of worse prognosis). The last 3 variables were independent significant prognostic factors in multivariate analysis and of the same importance in recurrence prediction (Receiver Operating Characteristic curves comparison p>0.05). Among the cases of recurrence, tumor progression was observed in 3 of 14. In 2 cases, LOH on 1p and/or coexistence of LOH 1p/14q correlated with anaplastic transformation.

Increased ratio of vascular endothelial growth factor to semaphorin3A is a negative prognostic factor in human meningiomas

Semaphorin3A (SEMA3A) is an anti-angiogenic factor which is expressed in human meningiomas in association with low microvessel density (MVD). It competes with vascular endothelial growth factor (VEGF) for receptor neuropilin-1 (NRP-1). The ratio between VEGF and SEMA3A has been recently demonstrated to regulate neo-angiogenesis, proliferation and progression of tumors. To clarify the involvement of these proteins in the above-mentioned phenomena, we analyzed the immunohistochemical expression of SEMA3A, VEGF and NRP-1 and their correlation with MVD in a series of 48 cases of meningioma with different histotype and histological grade. SEMA3A and VEGF expression was encountered in about half the cases, although at different levels. NRP-1 staining was evidenced in the vessels within all but two tumors and in the neoplastic cells of 18/48 meningiomas. A negative significant correlation emerged between SEMA3A amount and MVD; on the other hand, high VEGF levels appeared to be significantly associated with high MVD. A high VEGF/SEMA3A was significantly associated with high histological grade, proliferation index and MVD as well as with a higher recurrence rate of the meningiomas. Present data suggest that the balance between the expression of the pro-angiogenic factor VEGF and the anti-angiogenic SEMA3A may be involved in the regulation of neo-angiogenesis and proliferation in meningiomas, representing also a predictor of recurrences in these tumors. Further validation of our results may open the way for the use of drugs targeting not only VEGF, but also NRP-1 and SEMA3A to prevent recurrences of meningiomas.

Gamma Knife Radiosurgery for Cerebellopontine Angle Meningiomas

BACKGROUND:

Resection of cerebellopontine angle (CPA) meningiomas may result in significant neurological morbidity. Radiosurgery offers a minimally invasive alternative to surgery.

OBJECTIVE:

To evaluate, in a multicenter cohort study, the outcomes of patients harboring CPA meningiomas who underwent Gamma Knife radiosurgery (GKRS).

METHODS:

From 7 institutions participating in the North American Gamma Knife Consortium, 177 patients with benign CPA meningiomas treated with GKRS and at least 6 months radiologic follow-up were included for analysis. The mean age was 59 years and 84% were female. Dizziness or imbalance (48%) and cranial nerve (CN) VIII dysfunction (45%) were the most common presenting symptoms. The median tumor volume and prescription dose were 3.6 cc and 13 Gy, respectively. The mean radiologic and clinical follow-up durations were 47 and 46 months, respectively. Multivariate regression analyses were performed to identify the predictors of tumor progression and neurological deterioration.

RESULTS:

The actuarial rates of progression-free survival at 5 and 10 years were 93% and 77%, respectively. Male sex (P = .014), prior fractionated radiation therapy (P = .010), and ataxia at presentation (P = .002) were independent predictors of tumor progression. Symptomatic adverse radiation effects and permanent neurological deterioration were observed in 1.1% and 9% of patients, respectively. Facial spasms at presentation (P = .007) and lower maximal dose (P = .011) were independently associated with neurological deterioration.

CONCLUSION:

GKRS is an effective therapy for CPA meningiomas. Depending on the patient and tumor characteristics, radiosurgery can be an adjuvant treatment to initial surgical resection or a standalone procedure that obviates the need for resection in most patients.

Osteopontin expressions correlate with WHO grades and predict recurrence in meningiomas

Recurrence of meningiomas is a major prognostic issue. Although World Health Organization (WHO) histopathological grading correlates strongly with recurrence, it has some limitations, and predicting the biological behavior of grade I meningiomas is particularly difficult. Osteopontin (OPN) is a protein known to be involved in tumor progression. The purpose of this study is to determine expression of OPN in meningiomas and to investigate its correlation with WHO grades and tumor recurrence. Immunohistochemical (IHC) evaluation of expression of OPN was performed by two different methods to ensure reliability. OPN IHC and Allred scores were calculated on the basis of intensity and extent of staining. Both scores were in agreement and correlated significantly with meningioma grade and Ki-67 index. OPN scores were also significantly correlated with recurrence of WHO grade I meningiomas. Cut-off values for OPN IHC and OPN Allred scores between non-recurrent and recurrent grade I meningiomas were calculated as 70 and 5.5 respectively. We concluded that OPN is a valuable marker for grading meningiomas and for predicting the recurrence in WHO grade I tumors.

Predicting outcomes of patients with intracranial meningiomas using molecular markers of hypoxia, vascularity, and proliferation

BACKGROUND

The natural history of surgically treated intracranial meningiomas can be quite variable. Recurrence and patient outcome cannot currently be predicted with accuracy.

OBJECTIVE

To explore the potential roles of tumor hypoxia-regulated biological markers, preoperative imaging, measures of proliferation, and angiogenesis in predicting patient outcome.

METHODS

Tissue from 263 patients (average follow-up, 75 months) was examined for molecular markers hypoxia-inducible factor-1α (HIF-1α), carbonic anhydrase-IX (CA-IX), and glucose transporter-1 (Glut-1); vascular endothelial growth factor (VEGF); proliferation (MIB-1); and microvascular density (MVD) (Factor VIII). Preoperative magnetic resonance images were also examined for tumor size and peritumoral brain edema (PTBE).

RESULTS

VEGF, HIF-1α, CA-IX, and Glut-1 are positively correlated (P < .001-.005). PTBE was associated with higher grade (P = .03), larger tumors (P = .02), and log of MVD (P = .004). Progression-free survival (PFS) was associated with higher grade (P < .001), subtotal resection (P = .004), VEGF expression (P = .004), and log of MIB-labeling index (P < .001) on pairwise comparisons. Using multivariate analysis, PFS was associated with subtotal resection (HR 2.71, P = .027), higher grade (HR 6.29, P < .001), higher VEGF expression (HR 1.52, P = .038), and log of MIB-labeling index (HR 1.68, P = .005). Shorter overall survival was associated with subtotal resection (HR 3.23, P = .002), higher grade (HR 4.47, P < .001), higher expression of HIF-1α (HR 1.56, P < .001) and Glut-1 (HR 1.39, P = .02), and log of MIB-labeling index (HR 1.87, P < .001) when controlled for age.

CONCLUSION

HIF, VEGF, and MIB-1 are significantly correlated with tumor recurrence. With further study, these molecular markers may be used to predict outcome for patients with intracranial meningiomas.

Optic nerve sheath meningioma in the first decade of life: case report and review of the literature

Background/Aim

Tumors of the optic nerve are mostly either optic nerve gliomas or optic nerve sheath meningiomas (ONSMs). While gliomas occur in children, most meningiomas are slow-growing tumors affecting middle-aged individuals with progressive visual loss, proptosis, disc edema and optociliary veins on fundus examination. ONSMs are extremely rare in children, with only 14 cases reported in children under the age of 10 years. The purpose of this study is to describe an additional case and review clinical, radiologic and histopathological findings that can help differentiate such tumors in children and allow an early and accurate diagnosis.

Case Report

An 8-year-old girl had a 2-year history of progressive proptosis and total visual loss on the right side. A computed tomography scan revealed a well-defined intraconal mass with perioptic calcification. Magnetic resonance imaging showed a tumor surrounding the optic nerve and extending intracranially, with enhancement following gadolinium injection. The patient was submitted to fronto-orbital craniotomy for complete tumor excision. Histological studies identified the neoplasm as ONSM.

Conclusions

Though unusual, ONSMs may occur in children and, in these cases, present a much more aggressive behavior than in adults. ONSM should therefore be differentiated from optic glioma in children because of its aggressive behavior and need for different treatment modalities.

Correlation between dynamic contrast-enhanced perfusion MRI relative cerebral blood volume and vascular endothelial growth factor expression in meningiomas

PURPOSE

To determine whether there is a correlation between vascular endothelial growth factor (VEGF) expression and cerebral blood flow (CBV) measurements in dynamic contrast-enhanced susceptibility perfusion magnetic resonance imaging (MRI) and to correlate the perfusion characteristics in high- versus low-grade meningiomas.

METHODS AND MATERIALS

A total of 48 (24 high-grade and 24 low-grade) meningiomas with available dynamic susceptibility-weighted MRI were retrospectively reviewed for maximum CBV and semiquantitative VEGF immunoreactivity. Correlation between normalized CBV and VEGF was made using the Spearman rank test and comparison between CBV in high- versus low-grade meningiomas was made using the Wilcoxon test.

RESULTS

There was a significant (P = .01) correlation between normalized maximum CBV and VEGF scores with a Spearman correlation coefficient of 0.37. In addition, there was a significant (P < .01) difference in normalized maximum CBV ratios between high-grade meningiomas (mean 12.6; standard deviation 5.2) and low-grade meningiomas (mean 8.2; standard deviation 5.2).

CONCLUSION

The data suggest that CBV accurately reflects VEGF expression and tumor grade in meningiomas. Perfusion-weighted MRI can potentially serve as a useful biomarker for meningiomas, pending prospective studies.

Status of Ki-67, estrogen and progesterone receptors in various subtypes of intracranial meningiomas

Meningiomas are the most prevalent intracranial tumors in human being. Although, majority of these cases are of benign nature, malignant behavior might be seen in a number of patients. This study aimed to investigate the status of estrogen receptor, progesterone receptor and Ki-67 labeling index in different grades of surgical intracranial meningiomas. In this prospective study, 50 patients with intracranial meningiomas were operated at the department of neurosurgery, Tabriz Teaching Imam Reza Hospital; from February 2010 through January 2012. Tumor grade was determined histopathologically according to the World Health Organization (WHO) subtyping system. Status of estrogen and progesterone receptor, as well as the Ki-67 labeling index was determined by immunohistochemical approach and graded as 0 (absent), 1 (weak), 2 (moderate) and 3 (strong). The group of patients comprised 15 males (30%) and 35 females (70%) with a mean age of 71.76 +/- 10.20 (range: 49-87) years. WHO grades I, II and III tumors were reported in 68, 22 and 10% of the cases, respectively. Estrogen receptor, progesterone receptor and Ki-67 labeling index were detected in 20% (all grade 1), 98% (grade 1: 2%, grade 2: 22%, grade 3: 74%) and 38% (grade 1: 6%, grade 2: 22% and grade 3: 10%) of the cases, respectively. The rate of grade 1 estrogen receptor was significantly higher in WHO grade I tumors (29%) than in WHO grades II and III (zero for both, p = 0.02). Grade 2 progesterone receptor was significantly higher in WHO grade II tumors (72.7%) vs. WHO grades I (8.8%) or III (0%). On the other hand, the rate of grade 3 progesterone receptor was significantly higher in WHO grades I (85.3%) and III (100%) tumors than in WHO grade II (27.3%) (p = 0.01). The rate of grade 3 Ki-67 labeling index was significantly higher in WHO grade III tumors (100%) than in WHO grades I and II (zero for both, p < 0.001). This study showed that firstly, estrogen receptor is seldom expressed in patients with meningioma; however, its presence means a good prognosis. Secondly, Ki-67 labeling index is a marker of poor prognosis in these patients. Thirdly, although, progesterone receptors are frequently expressed in meningioma, their prognostic role varies greatly and needs to be determined in further studies.

Clinical features and immunohistochemical expression levels of androgen, estrogen, progesterone and Ki-67 receptors in relationship with gross-total resected meningiomas relapse

OBJECTIVE

To investigate the recurrent risk factors of intracranial meningiomas after gross-total resection (Simpson II Grade).

METHODS

We retrospectively analysed 162 meningiomas in the General Hospital of Shenyang Military Region and Changzheng Hospital in Shanghai China, which underwent nearly gross-total resection using microneurosurgery techniques from 2002 to 2007. Monofactorial and Cox regression statistics methods were carried out to analyse the relationship between the post-operation tumour relapse and some clinical features including the patient sex, age, tumour size, tumour shape, tumour pathological grade and the immunohistochemical expression levels of Ki-67, androgen receptor (AR), estrogen receptor (ER) and progesterone receptor (PR).

RESULTS

There are 53 recurrent meningiomas during the follow-up period. The recurrent rate is about 32.7%. Immunohistochemistry results indicate that AR, ER, PR, Ki-67 are positively expressed on some tumour cell nuclear. Cox regression analysis reveals that tumour size, tumour shape, pathological grade and Ki-67 expression levels are significantly correlated with the tumour relapse (p <0.05).

CONCLUSIONS

Our results demonstrate high recurrent rate for gross-total resection meningiomas. Tumour diameter exceeding 5 cm, irregular shape tumour, pathological grade II and III and positive expression of Ki-67 were the risk factors for post-operation meningioma relapse. The recurrent rate increases coincidentally with the follow-up period.

Bevacizumab therapy for adults with recurrent/progressive meningioma: a retrospective series

Intracranial meningiomas are often indolent tumors which typically grow over years to decades. Nonetheless, meningiomas that progress after maximum safe resection and radiation therapy pose a significant therapeutic challenge and effective therapies have yet to be identified. Preclinical studies implicate angiogenesis in the pathophysiology of more aggressive meningiomas, suggesting that anti-angiogenic therapies may be of utility in this setting. We performed a retrospective review of fourteen patients with recurrent meningioma treated at Duke University Medical Center with bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor, administered either alone or in combination with chemotherapy. Most patients were heavily pre-treated. Progression-free survival at 6 months was 86 % and was comparable regardless of meningioma grade and whether bevacizumab was administered as monotherapy or in combination with chemotherapy. Most toxicities were mild however single patients developed CNS hemorrhage (grade 1) and intestinal perforation (grade 4), respectively. Bevacizumab can be administered safely to patients with meningioma and appears to be associated with encouraging anti-tumor effect when administered as either a single agent or in combination with chemotherapy. Phase II trials investigating bevacizumab in patients with progressive/recurrent meningioma are warranted.

Radiological predictive factors for regrowth of residual benign meningiomas

The pre- and postoperative radiological predictive factors for the regrowth of residual benign meningiomas were investigated in 80 of 327 patients who underwent first surgery for intracranial meningioma, who met the following conditions: residual tumor observed on postoperative imaging, follow up for more than 5 years or until regrowth of the residual tumor, histological diagnosis of World Health Organization grade I, and no additional therapy performed within 1 month after surgery. These 80 patients were divided into those with no regrowth during the follow-up period (Group A, n = 54) and those with regrowth (Group B, n = 26), and the clinical characteristics and pre- and postoperative imaging findings were compared. Univariate analysis of factors influencing regrowth showed 6 factors were significant: tumor size ≥4 cm (p = 0.043), tumor volume ≥30 cm(3) (p = 0.026), presence of edema (p = 0.036), unclear brain-tumor interface (p < 0.001), presence of a pial-cortical blood supply (p = 0.031), and residual tumor volume ≥3.0 cm(3) (p < 0.001). Multivariate analysis showed only residual tumor volume ≥3.0 cm(3) was significant (p = 0.001). Generally, the significant imaging findings on univariate analysis suggest malignant meningioma. Similar findings may be observed even in grade I cases, and residual tumors may regrow in such cases. The possibility is particularly high if the residual tumor volume exceeds 3.0 cm(3), so early radiotherapy should be performed to prevent regrowth.

Study of effectiveness of mifepristone for glioma cell line growth suppression

OBJECTIVE

Glioblastoma multiforme is a malignant primary brain tumour with very limited treatment options. Any addition to existing treatment options which can improve prognosis and life expectancy is useful. In our study, we look at the usefulness of anti-progestogen mifepristone in causing growth suppression of glioma cell lines in the laboratory.

METHODS

We cultured five cell lines in the lab and exposed them to mifepristone in different doses for a total of 96 h. Five different doses of mifepristone were used. Progesterone and dexamethasone were also used as growth stimulants. Immunostaining was used to identify progesterone receptors (PRs) in the cell lines.

RESULTS

U257/7 and IN1265 showed statistically significant growth suppression (36% and 11%, P = 0.001 and 0.03 respectively), maximal at 96 h. Growth suppression in U257/7 showed a dose response progression except with the lowest dose which was not explicable. The response of IN1265 was seen only with the highest dose of mifepristone. There was no significant growth stimulation with either dexamethasone or progesterone. None of the cell lines showed any significant positivity for PRs.

CONCLUSION

We were able to produce enough growth suppression of glioma cell lines using mifepristone. This is in keeping with some of the published results in literature. This raises the possibility of using mifepristone in treating GBMs which have very limited treatment options. This, however, needs further work probably on primary glioma cultures first followed by in vivo studies before it can be used in patients.

Spinal meningiomas: age-related features

OBJECTIVES

Spinal meningiomas mainly occur in old patients, with a remarkable female prevalence. This study investigates the different features between younger and older patients in an adult population (>18 years).

MATERIALS AND METHODS

A surgical series of 120 adult patients operated on for spinal meningiomas at the Neurosurgical Clinic of the "Federico II" University of Naples is reviewed. In this series 117 patients with a sporadic spinal meningioma were divided in two groups: group I including 30 patients (25.6%) younger than 50 years of age, group II including 87 patients (74.4%) older than 50 years. 3 patients had a spinal meningioma and neurofibromatosis. Several parameters, including sex, predisposing factors, tumor location and growth, histology, recurrences, proliferation index Ki-67 LI, and outcome, are considered and compared in the two age groups.

RESULTS

Group I showed an incidence of high cervical spine (C1-C4) meningiomas higher than group II (23.3% vs 3.4%, p=0.026) and lower rate of thoracic tumors (60% vs 82.7%, p=0.04). No significant differences of histological type and Ki-67 LI were found. Group I had 2 cases of atypical meningiomas (6.6% vs 0%, ns). Recurrences occurred in 6.6% of group I and 2.6% of group II, with no significance. In recurrent meningiomas values of Ki-67 LI were significantly higher than values in not recurrent meningiomas (p=0.0001), whereas no difference of estrogen and progesterone receptor expression was noted.

CONCLUSIONS

Younger adult patients with spinal meningiomas show not rare occurrence of NF (9%) and significantly higher incidence of high cervical and lower incidence of thoracic localizations with respect to the older patients. On the other hand, there are not significant differences of histology, Ki-67 LI and recurrence rate, excepting for a slight difference for atypical meningiomas.

Angiogenesis in meningiomas

Neoangiogenesis has been correlated to biological aggressiveness and an adverse clinical course of several neoplasias. Its prognostic role in meningiomas appears to be controversial. Nonetheless, if adequately quantified with specific markers and appropriate scoring methods, angiogenesis seems to be significantly associated with a high growth fraction, development of recurrences and shorter overall survival of meningiomas. As a consequence, neoangiogenesis may represent a target for therapies aimed at reducing the growth of inoperable meningiomas or recurrence risk of totally resected tumors. Even more significantly, the identification of the factors that mediate angiogenesis in meningiomas could help us to determine appropriate novel anti-angiogenic therapies for these tumors. Herein the methods for quantification of angiogenesis as well as its regulating factors in meningiomas are reviewed.

Usefulness of thallium-201 SPECT in the evaluation of tumor natures in intracranial meningiomas

INTRODUCTION

Although intracranial meningiomas are regarded as benign tumors, some of them behave clinically as malignant tumors. Past reports suggest that MIB 1 and vascular endothelial growth factor (VEGF) in postoperative tumor specimens correlate with the aggressive nature of tumors, but preoperative prediction of such a nature is more useful for therapeutic planning for the tumor. The purpose of this study was to assess the usefulness of preoperative thallium-201 chloride single-photon emission computed tomography (Tl SPECT) to evaluate biological behavior in intracranial meningiomas.

METHODS

Tl SPECT was performed on 39 patients with intracranial meningioma and Tl uptake indices were calculated. The difference in the Tl uptake index between atypical meningiomas and other pathological types of meningioma was evaluated. Moreover, correlation of Tl uptake indices with the MIB1 labeling index was estimated. Tl uptake indices were also compared between VEGF strongly positive and weakly positive meningiomas.

RESULTS

The delayed index of atypical meningioma was significantly higher than that of the other pathological types (p = 0.036). Significant correlation was found between the Tl uptake index in the delayed image and MIB1 labeling index (p < 0.0001, R (2) = 0.36). Moreover, VEGF strongly positive meningiomas exhibited a significantly higher Tl uptake index compared to VEGF weakly positive meningiomas in both the early image and the delayed image (p = 0.029, 0.023, respectively).

CONCLUSIONS

Tl uptake index may be a possible preoperative surrogate marker of MIB1 and VEGF that is useful in detecting aggressive natures in intracranial meningiomas.

Long-term surgical outcome and biological prognostic factors in patients with skull base meningiomas

OBJECT

Although gross-total resection (GTR) is a preferable treatment for skull base meningiomas, subtotal resection (STR) with or without radiation therapy can be considered as an alternative treatment for patients at considerable surgical risk. The long-term prognosis of such patients might be related to the biological activity of the tumor. This study examined predictors of progression-free survival (PFS) and sought to determine the optimal treatment strategies, focusing on the pathobiological findings of skull base meningiomas.

METHODS

This study included 281 patients with skull base meningiomas (mean follow-up period 88.4 months). Risk factors for tumor progression were examined using a multivariate analysis. The PFS and overall survival (OS) rates were evaluated using the Kaplan-Meier method. The functional outcomes of the patients were measured using the Karnofsky Performance Scale (KPS).

RESULTS

The 10-year PFS and OS rates were 66.4% and 97.4%, respectively. Overall, 83.3% of patients achieved a favorable outcome, that is, an improved or unchanged KPS score. The extent of resection, additional radiotherapy, histological grade, MIB-1 index, and p53-positive rate were significantly associated with PFS. The PFS of patients undergoing STR without radiation therapy was significantly shorter than that of either those undergoing STR with radiation therapy or GTR, while no statistical difference was observed between the latter 2 groups. Among the patients undergoing STR with pathobiological risk factors (histological grade, MIB-1 index, and p53-positive rate), the PFS of the patients who received radiation therapy was better than that of those who did not receive radiation therapy. Among the patients undergoing STR without such risk factors, the PFS was not significantly different between patients who received radiation therapy and those who did not.

CONCLUSIONS

For patients with skull base meningiomas, a GTR is desirable and additional radiation therapy after STR may contribute to a longer PFS. Additional radiation therapy should be recommended, especially for patients with pathobiological risk factors, but not necessarily for those without such risks.

The significance of Ki-67/MIB-1 labeling index in human meningiomas: a literature study

Histology alone does not always predict the clinical outcome of human meningiomas. Determination of proliferative activity has therefore become an important diagnostic and prognostic tool to identify more aggressive meningiomas, and the Ki-67/MIB-1 monoclonal antibody has become widely used. The aim of this study was to assess the prognostic value of the Ki-67/MIB-1 labeling index (LI) in human meningiomas by a search in the literature. In PubMed/Medline databases, 53 articles were found, and they all showed positive correlations between Ki-67/MIB-1 LI and histological malignancy grade. The average mean labeling indices were 3%, 8%, and 17% for grade I-III meningiomas, respectively. There was, however, considerable overlap of indices between the malignancy groups. Concerning recurrence, meningiomas with a labeling index beyond 4% may indicate an increased relapse rate. Consequently, Ki-67/MIB-1 LI represents a useful predictor of tumor grade and risk of recurrence, however, it must be interpreted cautiously in the individual tumor.

Intraventricular meningioma after cranial irradiation for childhood leukemia

Meningiomas are among the most common brain tumors in adults. They are most commonly located over the cerebral convexities and are infrequently found in an intraventricular location. Ionizing cranial radiation is a risk factor for late occurrence of meningiomas within the radiation field. While pathologic grading of meningiomas is straightforward, significant variability often exists between pathologists in applying standard grading criteria. This has implications for prognosis. Radiation-induced meningiomas may also have predilection to recur. The authors describe a case of an intraventricular meningioma occurring 23 years after cranial irradiation for childhood acute lymphoblastic leukemia.

Risk profile associated with convexity meningioma resection in the modern neurosurgical era

OBJECT

Although meningiomas are commonly found along the supratentorial convexity, the risk profile associated with this subset of lesions in the modern neurosurgical era is unknown.

METHODS

The authors retrospectively reviewed the clinical course of patients with supratentorial convexity meningiomas treated during the past 10 years. All patients had undergone MR imaging within 72 hours after surgery and at least 1 year of clinical follow-up. Patients with multiple meningiomas, hemangiopericytomas, malignant meningiomas, or tumor-prone syndromes were excluded from analysis.

RESULTS

Between 1997 and 2007, 141 consecutive patients (median age 48 years, range 18-95 years) underwent resection of a supratentorial convexity meningioma. The most common signs or symptoms at presentation were headache (48%), seizures (34%), and weakness (21%). The mean tumor volume was 146.3 cm3 (range 1-512 cm3). There were no intraoperative complications or deaths. Medical or neurosurgical morbidity was noted in the postoperative course of 14 patients, equating to a 10% overall complication rate. Postoperative surgical complications included hematoma requiring evacuation, CSF leakage, and operative site infection. Medical complications included pulmonary embolus and deep vein thrombosis requiring treatment. A Simpson Grade 0 or 1 resection was achieved in 122 patients (87%). One hundred six tumors (75%) were WHO Grade I, whereas 35 (25%) were WHO Grade II. The median clinical follow-up was 2.9 years (range 1-10 years), and the median radiographic follow-up was 3.7 years (range 1-10 years). Six patients (4%) had radiographic evidence of tumor recurrence, with 3 (2%) undergoing repeat resection.

CONCLUSIONS

With the conservative recommendations for surgery for asymptomatic meningiomas and the advent of radiosurgery during the past 10 years, microsurgically treated convexity meningiomas are now typically large in size. Nevertheless, the patient's clinical course following microsurgical removal of these lesions is expected to be uncomplicated. The authors' findings provide a defined risk profile associated with the resection of supratentorial convexity meningiomas in the modern neurosurgical era.