Long-term outcomes of fractionated stereotactic radiotherapy for intracranial skull base benign meningiomas in single institution

Single fraction and hypofractionated radiosurgery for perioptic meningiomas-tumor control and visual outcomes: a systematic review and meta-analysis

Perioptic meningiomas, defined as those that are less than 3 mm from the optic apparatus, are challenging to treat with stereotactic radiosurgery (SRS). Tumor control must be weighed against the risk of radiation-induced optic neuropathy (RION), as both tumor progression and RION can lead to visual decline. We performed a systematic review and meta-analysis of single fraction SRS and hypofractionated radiosurgery (hfRS) for perioptic meningiomas, evaluating tumor control and visual preservation rates. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we reviewed articles published between 1968 and December 8, 2022. We retained 5 studies reporting 865 patients, 438 cases treated in single fraction, while 427 with hfRS. For single fraction SRS, the overall rate of tumor control was 95.1%, with actuarial rates at 5 and 10 years of 96% and 89%, respectively; tumor progression was 7.7%. The rate of visual stability was 90.4%, including visual improvement in 29.3%. The rate of visual decline was 9.6%, including blindness in 1.2%. For hfRS, the overall rate of tumor control was 95.6% (range 92.1-99.1, p < 0.001); tumor progression was 4.4% (range 0.9-7.9, p = 0.01). Overall rate of visual stability was 94.9% (range 90.9-98.9, p < 0.001), including visual improvement in 22.7% (range 5.0-40.3, p = 0.01); visual decline was 5.1% (range 1.1-9.1, p = 0.013). SRS is an effective and safe treatment option for perioptic meningiomas. Both hypofractionated regimens and single fraction SRS can be considered.

Concomitant Temozolomide plus radiotherapy for high-grade and recurrent meningioma: a retrospective chart review

Background

High-grade and recurrent meningiomas are often treatment resistant and pose a therapeutic challenge after surgical and radiation therapy (RT) failure. Temozolomide (TMZ) is a DNA alkylating agent that appears to have a radiosensitizing effect when used in combination with RT and may be worthwhile in meningioma treatment. Thus, we investigated the potential efficacy of concomitant RT plus TMZ compared to historical controls of just RT used in the treatment of high-grade and recurrent meningiomas.

Methods

We performed a retrospective analysis of patients with meningioma treated at the University of Colorado with TMZ chemoradiation. Progression free survival (PFS) and overall survival (OS) were calculated from the start of chemoradiation to local recurrence or death, respectively.

Results

Eleven patients (12 tumors) were treated with chemoradiation with a median follow-up of 41.5 months. There were two WHO grade 1, eight grade 2 and two grade 3 meningiomas. Three patients died during the follow-up period—one being disease related (11.1%). Two patients had meningioma recurrence—at 2.3 months (WHO grade 3), and 5.4 years (WHO grade 2). Three-year OS and PFS for grade 2 meningiomas were each 88%. Historical controls demonstrate a 3-year median OS and PFS of 83% and 75.8%, respectively.

Conclusions

Treatment options are limited for meningiomas after local failure. In this study, TMZ chemoradiation demonstrated no significant difference in PFS and OS in the treatment of grade 2 meningiomas compared to historic controls. Further study is warranted to find novel methods for the treatment of malignant and recurrent meningiomas.

Stereotactic Radiosurgery for Perioptic Meningiomas: An International, Multicenter Study

BACKGROUND

Stereotactic radiosurgery (SRS) is increasingly used for management of perioptic meningiomas.

OBJECTIVE

To study the safety and effectiveness of SRS for perioptic meningiomas.

METHODS

From 12 institutions participating in the International Radiosurgery Research Foundation (IRRF), we retrospectively assessed treatment parameters and outcomes following SRS for meningiomas located within 3 mm of the optic apparatus.

RESULTS

A total of 438 patients (median age 51 yr) underwent SRS for histologically confirmed (29%) or radiologically suspected (71%) perioptic meningiomas. Median treatment volume was 8.01 cm3. Median prescription dose was 12 Gy, and median dose to the optic apparatus was 8.50 Gy. A total of 405 patients (93%) underwent single-fraction SRS and 33 patients (7%) underwent hypofractionated SRS. During median imaging follow-up of 55.6 mo (range: 3.15-239 mo), 33 (8%) patients experienced tumor progression. Actuarial 5-yr and 10-yr progression-free survival was 96% and 89%, respectively. Prescription dose of ≥12 Gy (HR: 0.310; 95% CI [0.141-0.679], P = .003) and single-fraction SRS (HR: 0.078; 95% CI [0.016-0.395], P = .002) were associated with improved tumor control. A total of 31 (10%) patients experienced visual decline, with actuarial 5-yr and 10-yr post-SRS visual decline rates of 9% and 21%, respectively. Maximum dose to the optic apparatus ≥10 Gy (HR = 2.370; 95% CI [1.086-5.172], P = .03) and tumor progression (HR = 4.340; 95% CI [2.070-9.097], P < .001) were independent predictors of post-SRS visual decline.

CONCLUSION

SRS provides durable tumor control and quite acceptable rates of vision preservation in perioptic meningiomas. Margin dose of ≥12 Gy is associated with improved tumor control, while a dose to the optic apparatus of ≥10 Gy and tumor progression are associated with post-SRS visual decline.

Stereotactic radiotherapy of appropriately selected meningiomas and metastatic brain tumor beds with gamma knife icon versus volumetric modulated arc therapy

PURPOSE

To determine if the gamma knife icon (GKI) can provide superior stereotactic radiotherapy (SRT) dose distributions for appropriately selected meningioma and post-resection brain tumor bed treatments to volumetric modulated arc therapy (VMAT).

MATERIALS AND METHODS

Appropriately selected targets were not proximal to great vessels, did not have sensitive soft tissue including organs-at-risk (OARs) within the planning target volume (PTV), and did not have concave tumors containing excessive normal brain tissue. Four of fourteen candidate meningioma patients and six of six candidate patients with brain tumor cavities were considered for this treatment planning comparison study. PTVs were generated for GKI and VMAT by adding 1 mm and 3 mm margins, respectively, to the GTVs. Identical PTV V_100% -values were obtained for the GKI and VMAT plans for each patient. Meningioma and tumor bed prescription doses were 52.7-54.0 in 1.7-1.8 Gy fractions and 25 Gy in 5 Gy fractions, respectively. GKI dose rate was 3.735 Gy/min for 16 mm collimators.

RESULTS

PTV radical dose homogeneity index was 3.03 ± 0.35 for GKI and 1.27 ± 0.19 for VMAT. Normal brain D_1% , D_5% , and D_10% were lower for GKI than VMAT by 45.8 ± 10.9%, 38.9 ± 11.5%, and 35.4 ± 16.5% respectively. All OARs considered received lower maximum doses for GKI than VMAT. GKI and VMAT treatment times for meningioma plans were 12.1 ± 4.13 min and 6.2 ± 0.32 min, respectively, and, for tumor cavities, were 18.1 ± 5.1 min and 11.0 ± 0.56 min, respectively.

CONCLUSIONS

Appropriately selected meningioma and brain tumor bed patients may benefit from GKI-based SRT due to the decreased normal brain and OAR doses relative to VMAT enabled by smaller margins. Care must be taken in meningioma patient selection for SRT with the GKI, even if they are clinically appropriate for VMAT.

External beam radiation therapy for meningioma

Radiation therapy (RT) plays an important role in the management of meningioma. Surgery often remains the initial treatment of choice as it reduces mass effect and confirms the diagnosis and grade. However, RT has frequently been successful in the primary setting and is commonly employed as adjuvant therapy for incompletely resected tumors as well as for high-grade meningiomas regardless of resection extent. Some meningiomas develop in locations less amenable to resection or in patients who are poor surgical candidates, in which circumstances RT is particularly appropriate as primary treatment. Recent cooperative group studies including RTOG 0539 have better established the role of RT for meningioma. These studies suggest a role for adjuvant RT for completely resected Grade II meningioma, which was less clear historically. Ongoing clinical trials such as NRG BN 003 and ROAM will further clarify this. This chapter reviews the role of fractionated external beam RT for various grades of meningioma.

[Skull base meningioma: Clinical and radiological efficacy based on a quantitative volumetric analysis]

PURPOSE

To date, no correlation has been found between clinical and radiological efficacy after irradiation of skull base meningiomas. However, the evaluation of the radiological response was most often made by questionable methods that may have underestimated the radiological effectiveness of radiotherapy. The objective of this work is to verify this hypothesis by quantitative volumetric analysis.

MATERIAL AND METHODS

Data from 35 patients treated with either helical tomotherapy (45.7%) or fractionated stereotactic radiotherapy (54.3%) were retrospectively analysed. These were mainly women (94%) aged 59 (43-81) with lesions mainly of the cavernous sinus (60%). There was a median of 2 (1-4) symptoms and the main symptoms were visual impairment (39%), cranial nerve deficits (23.4%) and headaches (17.2%).

RESULTS

Median tumour volume decreased significantly (P<0.05) from 9.6mL (0.3-36.6) to 6.8mL (0.1-26.5) after median follow-up of 44 months (24-77). Sixty-three percent of patients had an improvement of at least one symptom. In univariate analysis, clinical efficacy (P<0.05), radiotherapy technique (P<0.05), tumor topography (P<0.05) and initial tumor volume (P<0.05) were predictive factors for radiological response. In multivariate analysis, only the inverse correlation between radiological response and initial tumor volume remained significant (ρ: -0.47 95% CI -3.2 to 5.7; P<0.05).

CONCLUSION

The quantitative volumetric monitoring demonstrates a major radiological efficiency of radiotherapy. However, no clear correlation between clinical and radiological efficacy was found.

An overview of meningiomas

Meningiomas are the most common primary intracranial tumor. Important advances are occurring in meningioma research. These are expected to accelerate, potentially leading to impactful changes on the management of meningiomas in the near and medium term. This review will cover the histo- and molecular pathology of meningiomas, including recent 2016 updates to the WHO classification of CNS tumors. We will discuss clinical and radiographic presentation and therapeutic management. Surgery and radiotherapy, the two longstanding primary therapeutic modalities, will be discussed at length. In addition, data from prior and ongoing investigations of other treatment modalities, including systemic and targeted therapies, will be covered. This review will quickly update the reader on the contemporary management and future directions in meningiomas. [Formula: see text].

Intermediate-risk meningioma: initial outcomes from NRG Oncology RTOG 0539

OBJECTIVE This is the first clinical outcomes report of NRG Oncology RTOG 0539, detailing the primary endpoint, 3-year progression-free survival (PFS), compared with a predefined historical control for intermediate-risk meningioma, and secondarily evaluating overall survival (OS), local failure, and prospectively scored adverse events (AEs). METHODS NRG Oncology RTOG 0539 was a Phase II clinical trial allocating meningioma patients to 1 of 3 prognostic groups and management strategies according to WHO grade, recurrence status, and resection extent. For the intermediate-risk group (Group 2), eligible patients had either newly diagnosed WHO Grade II meningioma that had been treated with gross-total resection (GTR; Simpson Grades I-III) or recurrent WHO Grade I meningioma with any resection extent. Pathology and imaging were centrally reviewed. Patients were treated with radiation therapy (RT), either intensity modulated (IMRT) or 3D conformal (3DCRT), 54 Gy in 30 fractions. The RT target volume was defined as the tumor bed and any nodular enhancement (e.g., in patients with recurrent WHO Grade I tumors) with a minimum 8-mm and maximum 15-mm margin, depending on tumor location and setup reproducibility of the RT method. The primary endpoint was 3-year PFS. Results were compared with historical controls (3-year PFS: 70% following GTR alone and 90% with GTR + RT). AEs were scored using NCI Common Toxicity Criteria. RESULTS Fifty-six patients enrolled in the intermediate-risk group, of whom 3 were ineligible and 1 did not receive RT. Of the 52 patients who received protocol therapy, 4 withdrew without a recurrence before 3 years leaving 48 patients evaluable for the primary endpoint, 3-year PFS, which was actuarially 93.8% (p = 0.0003). Within 3 years, 3 patients experienced events affecting PFS: 1 patient with a WHO Grade II tumor died of the disease, 1 patient with a WHO Grade II tumor had disease progression but remained alive, and 1 patient with recurrent WHO Grade I meningioma died of undetermined cause without tumor progression. The 3-year actuarial local failure rate was 4.1%, and the 3-year OS rate was 96%. After 3 years, progression occurred in 2 additional patients: 1 patient with recurrent WHO Grade I meningioma and 1 patient with WHO Grade II disease; both remain alive. Among 52 evaluable patients who received protocol treatment, 36 (69.2%) had WHO Grade II tumors and underwent GTR, and 16 (30.8%) had recurrent WHO Grade I tumors. There was no significant difference in PFS between these subgroups (p = 0.52, HR 0.56, 95% CI 0.09-3.35), validating their consolidation. Of the 52 evaluable patients, 44 (84.6%) received IMRT, and 50 (96.2%) were treated per protocol or with acceptable variation. AEs (definitely, probably, or possibly related to protocol treatment) were limited to Grade 1 or 2, with no reported Grade 3 events. CONCLUSIONS This is the first clinical outcomes report from NRG Oncology RTOG 0539. Patients with intermediate-risk meningioma treated with RT had excellent 3-year PFS, with a low rate of local failure and a low risk of AEs. These results support the use of postoperative RT for newly diagnosed gross-totally resected WHO Grade II or recurrent WHO Grade I meningioma irrespective of resection extent. They also document minimal toxicity and high rates of tumor control with IMRT. Clinical trial registration no.: NCT00895622 (clinicaltrials.gov).

[Base of the skull meningioma: Efficacy, clinical tolerance and radiological evaluation after radiotherapy]

Skull base meningioma leads to functional disturbances, which can significantly alter the quality of life. The optimal management of these lesions, whose goals are neurological preservation and tumour local control, is not yet clearly established. It is widely recognized that the goal of a radical excision should be abandoned despite the advances in the field of microsurgery of skull base lesions. Although less morbid, partial tumour excision would be associated with increased risk of local tumour recurrence. Although discussed both exclusive and adjuvant have proven to be highly successful in terms of clinical improvement and local control. Various radiation techniques have demonstrated their efficacy in the management of this pathology. However, high rates of clinical improvement are in contrast with low rates of radiological improvement. The notion of clinical and radiological dissociation appeared. However, in most of these studies, the analysis of the radiological response could be subject of legitimate criticism. This work proposes to review the local control, the efficacy and the clinical tolerance and the radiological response of the various radiation techniques for the meningioma of the base of the skull and to demonstrate the interest of quantitative volumetric analyses in the follow-up of meningioma after radiotherapy.

CyberKnife Stereotactic Radiosurgery and Hypofractionated Stereotactic Radiotherapy As First-line Treatments for Imaging-diagnosed Intracranial Meningiomas

Definitive radiotherapy is an important alternative treatment for meningioma patients who are inoperable or refuse surgery. We evaluated the efficacy and toxicity of CyberKnife-based stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (hSRT) as first-line treatments for intracranial meningiomas that were diagnosed using magnetic resonance imaging (MRI) and/or computed tomography (CT). Between February 2005 and September 2015, 41 patients with intracranial meningiomas were treated with CyberKnife-based SRS or hSRT. Eleven of those tumors were located in the skull base. The median tumor volume was 10.4 ml (range, 1.4–56.9 ml). The median prescribed radiation dose was 17 Gy (range, 13–20 Gy to the 61–88% isodose line) for SRS (n = 9) and 25 Gy (range, 14–38 Gy to the 44–83% isodose line) for hSRT (n = 32). The hSRT doses were delivered in 2 to 10 daily fractions. The median follow-up period was 49 months (range, 7–138). The 5-year progression-free survival rate (PFS) for all 41 patients was 86%. The 3-year PFS was 69% for the 14 patients with tumor volumes of ≥13.5 ml (30 mm in diameter) and 100% for the 27 patients with tumor volumes of <13.5 ml (P = 0.031). Grade >2 toxicities were observed in 5 patients (all of them had tumor volumes of ≥13.5 ml). SRS and hSRT are safe and effective against relatively small (<13.5 ml) meningiomas.

Hypofractionated stereotactic radiotherapy (HFSRT) for who grade I anterior clinoid meningiomas (ACM)

PURPOSE

While microsurgical resection plays a central role in the management of ACMs, extensive surgery may be associated with substantial morbidity particularly for tumors in intimate association with critical structures. In this study, we evaluated the use of HFSRT in the management of ACM.

MATERIALS AND METHODS

A total of 22 patients with ACM were treated using HFSRT. Frameless image guided volumetric modulated arc therapy (VMAT) was performed with a 6 MV linear accelerator (LINAC). The total dose was 25 Gy delivered in five fractions over five consecutive treatment days. Local control (LC) and progression free survival (PFS) rates were calculated using the Kaplan-Meier method. Common Terminology Criteria for Adverse Events, version 4.0 was used in toxicity grading.

RESULTS

Out of the total 22 patients, outcomes of 19 patients with at least 36 months of periodic follow-up were assessed. Median patient age was 40 years old (range 24-77 years old). Median follow-up time was 53 months (range 36-63 months). LC and PFS rates were 100 and 89.4 % at 1 and 3 years, respectively. Only two patients (10.5 %) experienced clinical deterioration during the follow-up period.

CONCLUSION

LINAC-based HFSRT offers high rates of LC and PFS for patients with ACMs.

Optic toxicity in radiation treatment of meningioma: a retrospective study in 213 patients

In this retrospective evaluation, we correlated radiation dose parameters with occurrence of optical radiation-induced toxicities. 213 meningioma patients received radiation between 2000 and 2013. Radiation dose and clinical data were extracted from planning systems and patients' files. The range of follow-up period was 2-159 months (median 75 months). Median age of patients was 60 years (range 23-86). There were 163 female and 50 male patients. In 140 cases, at least one of the neuro-optic structures (optic nerves and chiasm) was inside the irradiated target volumes. We found 15 dry eye (7 %) and 24 cataract (11.2 %) cases. Median dose to affected lachrymal glands was 1.47 Gy and median dose to affected lenses was 1.05 Gy. Age and blood cholesterol level in patients with cataract were significantly higher. Patients with dry eye were significantly older. Only two patients with visual problems attributable to radiation treatment were seen. They did not have any risk factors. Maximum and median delivered doses to neuro-optic structures were not higher than 57.30 and 54.60 Gy respectively. Low percentages of cases with radiation induced high grade optic toxicities show that modern treatment techniques and doses are safe. In very few patients with optic side effects, doses to organs at risk were higher than the defined constraint doses. This observation leads to the problem of additional risk factors coming into play. The role of risk factors and safety of higher radiation doses in high grade meningiomas should be investigated in more comprehensive studies.

Meningiomas: knowledge base, treatment outcomes, and uncertainties. A RANO review

Evolving interest in meningioma, the most common primary brain tumor, has refined contemporary management of these tumors. Problematic, however, is the paucity of prospective clinical trials that provide an evidence-based algorithm for managing meningioma. This review summarizes the published literature regarding the treatment of newly diagnosed and recurrent meningioma, with an emphasis on outcomes stratified by WHO tumor grade. Specifically, this review focuses on patient outcomes following treatment (either adjuvant or at recurrence) with surgery or radiation therapy inclusive of radiosurgery and fractionated radiation therapy. Phase II trials for patients with meningioma have recently completed accrual within the Radiation Therapy Oncology Group and the European Organisation for Research and Treatment of Cancer consortia, and Phase III studies are being developed. However, at present, there are no completed prospective, randomized trials assessing the role of either surgery or radiation therapy. Successful completion of future studies will require a multidisciplinary effort, dissemination of the current knowledge base, improved implementation of WHO grading criteria, standardization of response criteria and other outcome end points, and concerted efforts to address weaknesses in present treatment paradigms, particularly for patients with progressive or recurrent low-grade meningioma or with high-grade meningioma. In parallel efforts, Response Assessment in Neuro-Oncology (RANO) subcommittees are developing a paper on systemic therapies for meningioma and a separate article proposing standardized end point and response criteria for meningioma.

Long-term efficacy of fractionated radiotherapy for benign meningiomas

PURPOSE

To assess long term efficacy of fractionated stereotactic radiotherapy (fSRT) in the treatment of benign intracranial meningiomas.

MATERIALS AND METHODS

Retrospective study of 222 patients with histologically confirmed (58%) and unverified presumed (42%) grade I intracranial meningioma treated with fSRT in a single institution to doses of 50-55Gy in 30-33 fractions.

RESULTS

At a median follow-up of 43months (range 3-144) the 5 and 10years local control (LC) were 93% and 86%. Patients with tumors involving the optic nerve (42 patients) and patients with cavernous sinus/parasellar region meningiomas (78 patients) had 5 and 10years LC of 100%. The 5 and 10years survival probabilities were 93% and 84%. On multivariate analysis gender and tumor site were independent predictors of LC. Worsening of pre-existing cranial nerve deficit occurred in 8 (3.5%) and onset of new deficit in 1 (0.5%) patient. Two patients with optic nerve sheath meningioma (1%) developed radiation retinopathy. There were no cases of radiation necrosis or second brain tumors.

CONCLUSION

fSRT achieves excellent medium and long term tumor control with minimal morbidity particularly in patients with benign meningiomas involving the parasellar region and the optic nerves and questions the role of other treatment modalities for tumors at these locations.

State-of-the-art treatment alternatives for base of skull meningiomas: complementing and controversial indications for neurosurgery, stereotactic and robotic based radiosurgery or modern fractionated radiation techniques

For skull base meningiomas, several treatment paradigms are available: Observation with serial imaging, surgical resection, stereotactic radiosurgery, radiation therapy or some combination of both. The choice depends on several factors. In this review we evaluate different treatment options, the outcome of modern irradiation techniques as well as the clinical results available, and establish recommendations for the treatment of patients with skull-base meningiomas.

Endocrine and visual function after fractionated stereotactic radiotherapy of perioptic tumors

PURPOSE

To find out whether the use of stereotactic techniques for fractionated radiotherapy reduces toxicity to the endocrine and visual system in patients with benign perioptic tumors.

PATIENTS AND METHODS

From 1993 to 2009, 29 patients were treated with fractionated stereotactic radiotherapy. The most frequent tumor types were grade I meningioma (n = 11) and pituitary adenoma (n = 10, 7 nonfunctioning, 3 growth hormone-producing). Patients were immobilized with the GTC frame (Radionics, USA) and the planning target volume (PTV; median 24.7, 4.6-58.6 ml) was irradiated with a total dose of 52.2 Gy (range, 45.0-55.8 Gy) in 1.8-Gy fractions using a linear accelerator (6 MeV photons) equipped with a micro-multileaf collimator. Maximum doses to the optic system and pituitary gland were 53.4 Gy (range, 11.5-57.6 Gy) and 53.6 Gy (range, 12.0-57.9 Gy).

RESULTS

Median follow-up was 45 months (range, 10-105 months). Local control was achieved in all but 1 patient (actuarial rate 92% at 5 years and 10 years). In 9 of 29 patients (31%), partial remission was observed (actuarial response rate 40% at 5 years and 10 years). In 4 of 26 patients (15%) with at least partial pituitary function, new hormonal deficits developed (actuarial rate 21% at 5 years and 10 years). This rate was significantly higher in patients treated for a larger PTV (< /> 25 ml: 0% vs. 42% at 5 years and 10 years, p = 0.028). Visual function improved in 4 of 15 patients (27%) who had prior impairment. None of the patients developed treatment-related optic neuropathy, but 2 patients experienced new disease-related visual deficits.

CONCLUSION

Fractionated stereotactic radiotherapy for benign tumors of the perioptic and sellar region results in satisfactory response and local control rates and does not affect the visual system. The assumption that patients can be spared hypophyseal insufficiency only holds for small tumors.

Pediatric meningiomas in The Netherlands 1974-2010: a descriptive epidemiological case study

OBJECTIVE

The purpose of this study was to review the epidemiology and the clinical, radiological, pathological, and follow-up data of all surgically treated pediatric meningiomas during the last 35 years in The Netherlands.

METHODS

Patients were identified in the Pathological and Anatomical Nationwide Computerized Archive database, the nationwide network and registry of histopathology and cytopathology in The Netherlands. Pediatric patients of 18 years or younger at first operation in 1974-2009 with the diagnosis meningioma were included. Clinical records, follow-up data, radiological findings, operative reports, and pathological examinations were reviewed.

RESULTS

In total, 72 patients (39 boys) were identified. The incidence of operated meningiomas in the Dutch pediatric population is 1:1,767,715 children per year. Median age at diagnosis was 13 years (range 0-18 years). Raised intracranial pressure and seizures were the most frequent signs at presentation. Thirteen (18 %) patients had neurofibromatosis type 2 (NF2). Fifty-three (74 %) patients had a meningioma World Health Organization grade I. Total resection was achieved in 35 of 64 patients. Fifteen patients received radiotherapy postoperatively. Mean follow-up was 4.8 years (range 0-27.8 years). Three patients died as a direct result of their meningioma within 3 years. Four patients with NF2 died as a result of multiple tumors. Nineteen patients had disease progression, requiring additional treatment.

CONCLUSION

Meningiomas are extremely rare in the pediatric population; 25 % of all described meningiomas show biological aggressive behavior in terms of disease progression, requiring additional treatment. The 5-year survival is 83.9 %, suggesting that the biological behavior of pediatric menigiomas is more aggressive than that of its adult counterparts.