Meningiomas: causes and risk factors

Interdisciplinary Therapeutic Approaches to Atypical and Malignant Meningiomas

Meningiomas have the highest incidence among brain tumors. In contrast to benign tumors that constitute the majority of this tumor entity, the treatment of aggressive meningiomas (WHO Grade 2 and 3) is more challenging, requiring gross total removal of the tumor and the affected dura and adjuvant radiotherapy. Sometimes the location and/or the configuration of the tumor do not favor radical surgical resection without endangering the patient's clinical condition after surgery and pharmacological therapy has, until now, not been proven to be a reliable alternative. Discussion: In this narrative review, we discuss the current literature with respect to the management of meningiomas, discussing the importance of the grade of resection in the overall prognosis of the patient and in the planning of adjuvant therapy. Conclusions: According to the location and size of the tumor, radical resection should be taken into consideration. In patients with aggressive meningiomas, adjuvant radiotherapy should be performed after surgery. In cases of skull base meningiomas, a maximal, though safe, resection should take place before adjuvant therapy. An interdisciplinary approach is beneficial for patients with primary or recurrent meningioma.

Clinical tool for prognostication of discharge outcomes following craniotomy for meningioma

BACKGROUND

Patients' comorbidities might affect the immediate postoperative morbidity and discharge disposition after surgical resection of intracranial meningioma.

OBJECTIVE

To study the impact of comorbidities on outcomes and provide a web-based application to predict time to favorable discharge.

METHODS

A retrospective review of the prospectively collected national inpatient sample (NIS) database was conducted for the years 2009-2013. Time to favorable discharge was defined as hospital length of stay (LOS). A favorable discharge was defined as a discharge to home and a non-home discharge destination was defined as an unfavorable discharge. Cox proportional hazards model was built. Full model for time to discharge and separate reduced models were built.

RESULTS

Of 10,757 patients who underwent surgery for meningioma, 6554 (60%) had a favorable discharge. The median hospital LOS was 3 days (interquartile range [IQR] 2-5). In the full model, several clinical and socioeconomic factors were associated with a higher likelihood of unfavorable discharge. In the reduced model, 13 modifiable comorbidities were negatively associated with a favorable discharge except for drug abuse and obesity, which are not associated with discharge. Both models accurately predicted time to favorable discharge (c-index:0.68-0.71).

CONCLUSION

We developed a web application using robust prognostic model that accurately predicts time to favorable discharge after surgery for meningioma. Using this tool will allow physicians to calculate individual patient discharge probabilities based on their individual comorbidities and provide an opportunity to timely risk stratify and address some of the modifiable factors prior to surgery.

Secondary meningioma after cranial irradiation: case series and comprehensive literature review

BACKGROUND

Secondary meningioma after cranial irradiation, so-called radiation-induced meningioma, is one of the important late effects after cranial radiation therapy. In this report, we analyzed our case series of secondary meningioma after cranial irradiation and conducted a critical review of literature to reveal the characteristics of secondary meningioma.

MATERIALS AND METHODS

We performed a comprehensive literature review by using Pubmed, MEDLINE and Google scholar databases and investigated pathologically confirmed individual cases. In our institute, we found pathologically diagnosed seven cases with secondary meningioma between 2000 and 2018. Totally, 364 cases were analyzed based on gender, WHO grade, radiation dose, chemotherapy. The latency years from irradiation to development of secondary meningioma were analyzed with Kaplan-Meier analysis. Spearman's correlation test was used to determine the relationship between age at irradiation and the latency years.

RESULTS

The mean age at secondary meningioma development was 35.6 ± 15.7 years and the mean latency periods were 22.6 ± 12.1 years. The latency periods from irradiation to the development of secondary meningioma are significantly shorter in higher WHO grade group (P = 0.0026, generalized Wilcoxon test), higher radiation dose group (P < 0.0001) and concomitant systemic chemotherapy group (P = 0.0003). Age at irradiation was negatively associated with the latency periods (r = -0.23231, P < 0.0001, Spearman's correlation test).

CONCLUSION

Cranial irradiation at older ages, at higher doses and concomitant chemotherapy was associated with a shorter latency period to develop secondary meningiomas. However, even low-dose irradiation can cause secondary meningiomas after a long latency period. Long-term follow-up is necessary to minimize the morbidity and mortality caused by secondary meningioma after cranial irradiation.

Metformin Is Associated with a Lower Incidence of Benign Brain Tumors: A Retrospective Cohort Study in Patients with Type 2 Diabetes Mellitus

Background: The risk of benign brain tumors (BBT) associated with metformin use has not received much attention. Therefore, a retrospective cohort study was designed to investigate such an association in patients with type 2 diabetes mellitus (T2DM). Methods: We used the database of Taiwan's National Health Insurance to enroll 152,176 ever users and 16,120 never users of metformin for the follow-up of incidence of BBT and a more specific outcome of cerebral meningioma. The patients were newly diagnosed with T2DM between 1999 and 2005; and they were followed up from 1 January 2006 until 31 December 2011. Hazard ratios were estimated by Cox regression incorporated with the inverse probability of treatment weighting using propensity score. Results: During follow-up, 111 never users and 557 ever users were diagnosed with BBT. For BBT, the respective incidence rates for never users and ever users were 153.95 per 100,000 person-years and 77.61 per 100,000 person-years. While ever users were compared to never users, the hazard ratio was 0.502 (95% confidence interval: 0.409-0.615). A dose-response pattern was seen when ever users were categorized into tertiles of cumulative duration of metformin therapy (cutoffs: <27.10 months, 27.10-58.27 months and >58.27 months) with respective hazard ratios of 0.910 (0.728-1.138), 0.475 (0.375-0.602) and 0.243 (0.187-0.315). For cerebral meningioma, the overall hazard ratio was 0.506 (0.317-0.808); and the hazard ratios comparing the respective tertiles to never users were 0.895 (0.531-1.508), 0.585 (0.346-0.988) and 0.196 (0.104-0.369). Conclusions: A reduced risk of BBT and cerebral meningioma is observed in metformin users in patients with T2DM.

Intracranial meningioma in two coeval adult cats from the same litter

Case summary

In this report we describe the occurrence of intracranial meningioma in two adult cats from the same litter. The location of the meningioma varied: one tumour was at the level of the brainstem, and the other was affecting the temporal and piriform lobes. The cat with the brainstem meningioma was treated with radiotherapy and the littermate had a rostrotentorial craniectomy for tumour removal. Both cats had a histopathological diagnosis of grade I meningioma of a predominantly fibrous subtype.

Relevance and novel information

Cases of familial meningioma in cats have not previously been described in the veterinary literature. However, familial meningioma is well described in humans and it is possible that cases are underestimated in animals. We discuss the possible genetic background and other causes, as well as challenges we may face in veterinary medicine in identifying these associations.

Depression and anxiety in recurrent giant cell tumor of bone

Giant cell tumor of bone (GCTB) is a benign neoplasia more frequently encountered in young females. The pathogenic and evolutionary dynamics of the disease is strongly influenced by the presence of depression and cellular mechanisms, especially proinflammatory and immune. Although it is not a malignant tumor, it is often recurrent, which determines a high level of depression, anxiety, and fear of the patients. Cytokine mechanisms, especially through increased tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6), as well as the involvement of the receptor activator of nuclear factor-kappa B (RANK)–RANK ligand (RANK-L) system, can be correlated with the risk of malignancy. Unfavorable evolution is associated with persistent pain, difficulties of movement and body dysmorphic symptoms. The diagnosis is based mainly on histopathological (HP) assessment. The patients can be treated with pharmacological agents (Denosumab), surgery with tumor excision, reconstruction or osteosynthesis, and radiotherapy. Patients with GCTB require HP and imaging evaluations, especially of relapses, to detect the risk of metastasis or malignancy, simultaneously with psychological and psychiatric monitoring to detect depression, addictive behaviors, and suicide risk. It is necessary to evaluate in a multidisciplinary team to avoid unfavorable oncological and psychiatric developments. Through its clinical, HP, and therapeutic features, GCTB has multiple connections with the psychological and psychopathological dimension.

Histopathological Correlation (World Health Organization Classification) of Meningiomas and Their Anatomical Localization: A Multicenter Epidemiological Study in Mexico

OBJECTIVE

To determine the epidemiology of the localization and histological type of meningiomas in the Mexican population and the distribution of the different histological patterns and their relationship to tumor localization and patient demographics.

METHODS

A retrospective analysis was performed in 5 hospitals in Mexico from 2009 to 2019. For qualitative variables, mean values were compared using Pearson χ² test for the correlation between location and histological pattern as well as the clinical presentation and the patient's sex. Student t test was performed for age and its correlation with location and histology.

RESULTS

Analysis of 179 patients revealed significant differences in histopathological pattern, patient sex, and tumor location. No significant differences were found for age or clinical presentation in association with any specific histological pattern.

CONCLUSIONS

There was a correlation between the histology of the 15 histopathological varieties of meningiomas and the predilection site of appearance as well as certain demographic aspects, such as sex. This study lays the foundation for future studies in Mexico on the differentiation and typing of meningiomas regardless of the histological grade to which they belong, as the exact behavior of these tumors, including grade I tumors, remains unknown to date.

Paraplegia due to spinal meningioma during the third trimester of pregnancy: case report and literature review

INTRODUCTION

Spinal meningiomas represent 25-45% of intradural spinal tumors and ~2% of meningiomas of the central nervous system (CNS), and their occurrence during pregnancy is unusual. We present an updated literature review.

CASE REPORT

A 36-year-old woman, at 32.6 weeks of gestation, was hospitalized for urinary tract infection and urinary retention. One month earlier, she had decreased strength in lower limbs, and this weakness rapidly progressed to flaccid paraplegia without sphincters control. Magnetic resonance imaging (MRI) revealed a well-defined intradural extramedullary lesion in T3-T4. Using a posterolateral approach, the tumor was completely removed; however, there was no clinical improvement, and the patient was discharged with an impairment scale (AIS) grade A. Histopathology examination indicated a psammomatous meningioma.

DISCUSSION

Meningiomas are benign tumors that are slowly progressive; however, the hemodynamic and hormonal changes of pregnancy are related to their accelerated growth. Reports show that the onset of the symptoms during the third trimester of pregnancy, including early neurological symptoms or signs of spinal cord compression, can be easily attributed to those of pregnancy by both the patient and the doctor. The time to diagnosis and medulla compression time are thus prolonged, which can be further compounded in middle-high income countries due to limitations in obtaining images for evaluation. Although rare, spinal meningiomas should be considered in the differential diagnosis of patients with neurological symptoms during pregnancy. Their early recognition is important to avoid irreversible neurological damage.

Increased Risk of Subsequent Meningioma Among Women with Malignant Breast Cancer

OBJECTIVE

Despite the increasing evidence of the association between breast cancer and meningioma in women, the relationship between these tumors remains improperly examined. In this study, we aim to identify the sociodemographic and clinicopathologic features of women with breast cancer associated with a higher risk of developing a meningioma.

METHODS

The SEER (Surveillance Epidemiology and End Results) database (18 registries) was used to identify women with breast cancer as their first neoplasm. The risk of subsequent meningioma was reported as the standardized incidence ratio (SIR) and was analyzed by sociodemographic and clinicopathologic subgroups. Results are given as SIR (95% confidence interval [CI]).

RESULTS

A total of 564,516 women diagnosed with breast cancer between 2004 and 2016 were included for analysis. A 26% increased risk of meningioma development (SIR, 1.26; 95% CI, 1.19-1.33; P < 0.05) was found in the cohort compared with the general population. Patients aged between 18 and 49 years (SIR, 2.16; 95% CI, 1.78-2.61; P < 0.05) and those with a more advanced tumor stage (stage IV; SIR, 2.39; 95% CI, 1.71-3.25; P < 0.05) were at a higher risk. Hormone receptor expression and treatment modality subgroups were at a similar risk compared with the general population.

CONCLUSIONS

Our study corroborated the known association between these tumors and found a 26% risk of meningioma development in women with breast cancer, with younger patients and those with a more aggressive disease having a higher than expected risk.

Demographics and outcome of histologically confirmed intracranial meningiomas

Objective:

Meningiomas represent the most common intracranial extraaxial neoplasia in adults, accounting for a third of all diagnosed primary tumors of the brain. Despite decades of research, relatively little data on demographics of meningiomas exist. The aim of our study was to undertake an analysis of demographics and outcome of patients who underwent meningioma surgery over an 8-year time period at our institution.

Methods:

We reviewed 187 consecutive patients with histologically confirmed meningioma. Demographic data, tumor location and side, surgical resection grade, and histopathological and radiological data were collected and assessed for all patients. Furthermore, recurrence, morbidity, and mortality were evaluated.

Results:

Of the 187 consecutive patients undergoing meningioma resection over a period of 8 years, 131 (70.1%) were women ( p < 0.001). Meningiomas were classified as World Health Organization (WHO) grade I, grade II, and grade III in 66.8%, 31.0%, and 2.1%, of the cases, respectively ( p < 0.001). MIB-1 proliferation index was <1 in 7.5%, 1–5 in 52.9%, 6–10 in 22.4%, >10 in 11.8% of the lesions ( p < 0.001). In 82.4% of the cases, gross total resection was achieved. Recurrence occurred in 23 patients (12.3%), while overall morbidity and mortality rate was 41.2% and 7.7%, respectively.

Conclusion:

Based on our results, women are more than twice as likely to be affected, and the peak age is between 60 years and 70 years. Recurrence rate in our cohort was relatively low when compared to the data in the literature. The diagnosis of WHO grade II meningiomas, 31% in our cohort, is increasing since the 2007 WHO criteria have been published.

Association of hormone replacement therapy with increased risk of meningioma in women: A hospital-based multicenter study with propensity score matching

AIM

There is no consensus regarding the association between hormone replacement therapy (HRT) and risk of meningioma so far. We conducted the first study among Chinese female patients to investigate the influence of HRT use on the risk of meningioma.

METHODS

We retrospectively collected records of diagnosis of meningioma for women aged 50 years and above during 2011-2016 and dispense of HRT prior to meningioma diagnosis in three tertiary hospitals in China. Meningioma cases were matched with controls at a ratio of 1:2 by using nearest neighbor propensity scores matching in order to balance the baseline characteristics between groups, which generated a total of 629 cases with 1258 controls.

RESULTS

We observed prior use of HRT associated with increased risk of meningioma (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.0-1.4) and the association was more prominent among women having multiple HRT dispenses and longer term exposure (OR, 1.3; 95% CI, 1.1-1.6), among those with combination therapy of estrogens and progestogens (OR, 1.3; 95% CI, 1.1-1.7) than monotherapy, and among progestogen users than estrogen users as for monotherapy. Furthermore, vaginal, subcutaneous implant seems to be associated with a higher risk of meningioma compared with oral administration although no significance had been reached.

CONCLUSION

This case-control study provides evidence that hormone use for an HRT purpose might constitute the development and growth of meningioma as an independent risk factor, especially for combination therapy and/or long-term users, which supports that meningioma might be a hormone-sensitive tumor.

Relationships Between Neurofibromatosis-2, Progesterone Receptor Expression, the Use of Exogenous Progesterone, and Risk of Orbitocranial Meningioma in Females

Background: The pathogenesis of meningioma in females and its association with exogenous progesterone is remained unclear. This study was aimed to examine expression of Progesterone receptor (PR) and Neurofibromatosis-2 (NF2) and assess their relationships to history of exogenous progesterone use and risk of meningioma.

Methods: Our study was a case-control study that involves 115 females, 40 cases who diagnosed with orbito-cranial meningioma and 75 controls of healthy, that has been presented in previous study. The demographic characteristics, reproductive factors, and history of progesterone use were obtained in–depth face-to-face interviews. PR and NF2 mRNA were assessed by real-time quantitative polymerase chain reaction (RT-qPCR) on serum specimens.

Results: The mean age of participants in cases vs. controls were 46.6 ± 6.2 vs. 46.5 ± 7.45 (P = 0.969). The expression of PR and NF2 in cases was significantly lower than in controls. The longer duration of progesterone exposure was significantly associated with lower expression of PR and NF2. Significant association between lower expression of PR (OR 11.7; 95% CI 4.17–32.9; P < 0.001 comparing the lowest quartile vs. 3 highest quartile of PR) and NF2 (OR 4.23; 95% CI 1.85–9.67; P = 0.001 comparing the 2 lowest quartiles vs. 2 highest quartiles) with increased risk of meningioma were also reported.

Conclusion: In this study we showed that the longer the exposure to exogenous progesterone, the lower the expression of PR and NF2 mRNA in the serum. Low expression of PR and NF2 were associated with higher risk of meningioma, suggesting that low PR expression and inactivation of NF2 might play a key role in progesterone-associated meningioma tumorigenesis and may be potential clinical marker for females at higher risk of meningioma.

The diagnostic value of texture analysis in predicting WHO grades of meningiomas based on ADC maps: an attempt using decision tree and decision forest

OBJECTIVES

The preoperative prediction of the WHO grade of a meningioma is important for further treatment plans. This study aimed to assess whether texture analysis (TA) based on apparent diffusion coefficient (ADC) maps could non-invasively classify meningiomas accurately using tree classifiers.

METHODS

A pathology database was reviewed to identify meningioma patients who underwent tumour resection in our hospital with preoperative routine MRI scanning and diffusion-weighted imaging (DWI) between January 2011 and August 2017. A total of 152 meningioma patients with 421 preoperative ADC maps were included. Four categories of features, namely, clinical features, morphological features, average ADC values and texture features, were extracted. Three machine learning classifiers, namely, classic decision tree, conditional inference tree and decision forest, were built on these features from the training dataset. Then the performance of each classifier was evaluated and compared with the diagnosis made by two neuro-radiologists.

RESULTS

The ADC value alone was unable to distinguish three WHO grades of meningiomas. The machine learning classifiers based on clinical, morphological features and ADC value could achieve equivalent diagnostic performance (accuracy = 62.96%) compared to two experienced neuro-radiologists (accuracy = 61.11% and 62.04%). Upon analysis, the decision forest that was built with 23 selected texture features and the ADC value from the training dataset achieved the best diagnostic performance in the testing dataset (kappa = 0.64, accuracy = 79.51%).

CONCLUSIONS

Decision forest with the ADC value and ADC map-based texture features is a promising multiclass classifier that could potentially provide more precise diagnosis and aid diagnosis in the near future.

KEY POINTS

• A precise preoperative prediction of the WHO grade of a meningioma brings benefits to further treatment plans. • Machine learning models based on clinical, morphological features and ADC value could achieve equivalent diagnostic performance compared to experienced neuroradiologists. • The decision forest model built with 23 selected texture features and the ADC value achieved the best diagnostic performance (kappa = 0.64, accuracy = 79.51%).

Rare Case of Convexity Meningioma Growing into Arachnoid Cyst

BACKGROUND

Meningioma growing into an arachnoid cyst is an extremely rare event. Only 3 cases are reported in the literature. In 2 of them, an operative procedure in or near the arachnoid cyst preceded tumor growth.

CASE DESCRIPTION

We report a case of a patient requiring marsupialization of an arachnoid cyst of the middle cranial fossa. On follow-up, 3 years postoperatively he showed no signs of recurrence or tumor growth. One year later, the fourth year after surgery on the cyst, he presented with large tumor growth into the former cyst's cavity. Pathologic workup after resection revealed an atypical meningioma (World Health Organization grade II).

CONCLUSIONS

We discuss the possible pathogenesis in light of the scarce published literature, as well as the differential diagnosis of this rapidly growing tumor.

3D Fast Spin-Echo T1 Black-Blood Imaging for the Preoperative Detection of Venous Sinus Invasion by Meningioma : Comparison with Contrast-Enhanced MRV

OBJECTIVES

To prospectively evaluate the diagnostic value of 3D fast spin-echo (FSE) T1 black-blood magnetic resonance (MR) imaging (3D CUBE T1WI) in comparison with contrast-enhanced MR venography (CE-MRV) in the detection of sinus invasion by meningiomas.

METHODS

In this study forty consecutive patients with suspected meningiomas adjacent to venous sinus underwent conventional MR imaging, CE-MRV and 3D CUBE T1WI scans. Images obtained by each technique were assessed independently by two neuroradiologists for (1) wall invasion and (2) lumen occlusion of the target venous sinus.

RESULTS

The use of 3D CUBE T1W imaging was found to provide an easy way to detect the venous wall invasion by para-sinus lesions. The interobserver agreement was excellent (κ = 0.843; 95% confidence interval CI 0.757-0.929) and the result was highly consistent with the surgical findings (sensitivity 90.48%, specificity 94.12%). In the analysis of the lumen occlusion, the interobserver agreement obtained by 3D CUBE T1WI sequence was excellent (κ = 0.956; 95% CI, 0.913-0.999) with a diagnostic accuracy of 94.74%, which surpassed CE-MRV not only in interobserver agreement (κ = 0.736; 95% CI, 0.639-0.833) but also in diagnostic value (accuracy = 68.42%). Among 38 patients with meningiomas, the existence and extent of peritumoral edema did not correlate with the invasion of adjacent venous sinus.

CONCLUSION

Currently, 3D CUBE T1WI sequence is a reliable technique to provide accurate assessment about the venous sinus invasion by meningioma. Meanwhile, CE-MRV is more suitable in the evaluation of the bypass draining veins around the tumor.

Sudden Unexpected Deaths Due to Intracranial Meningioma: Presentation of Six Fatal Cases, Review of the Literature, and A Discussion of the Mechanisms of Death

Deaths due to meningiomas are routinely diagnosed in clinical practice because this neoplasm tends to present with the typical progression of neurological deficits. On the other hand, sudden unexpected deaths due to meningiomas are rarely described in the literature. The study presents six fatal cases of previously undiagnosed intracranial meningiomas from the Cook County Medical Examiner's Office from 1998 to 2014. The most common explanation of the mechanism of sudden death due to intracranial neoplasms is a rapid increase in intracranial pressure produced by the mass effect of the neoplasm. Other mechanisms of death include acute intracranial and intratumoral hemorrhage, and benign neoplasms that grow in the vicinity of vital centers altering neural discharge in autonomic pathways leading to cardiac suppression or lethal arrhythmia. Forensic pathologists must keep in mind that sudden unexpected death caused by intracranial meningiomas, although extremely rare, may be encountered in the forensic setting.

[Extra-axial tumors of the central nervous system]

Extra-axial tumors are intracranial neoplasms but are not located within the brain parenchyma. The localization of intracranial neoplasms helps to narrow down the possible differential diagnoses and also plays a deciding role in the treatment strategy and the prognosis. For this reason exact localization of these lesions is extremely important. Extra-axial tumors are the most common neoplasms among adults. They can be divided in a broad spectrum of histopathological subgroups. The most common extra-axial tumors are meningiomas, which arise from the dura mater. In the vast majority of cases they are benign and slowly growing. Only a few rare subgroups show aggressive behavior.

Multiple meningiomas in a woman irradiated in utero

Meningiomas are a common central nervous system tumour and radiation is a known risk factor for their development. In utero radiation exposure correlates to developmental abnormalities and carcinogenesis in a dose- and gestational age-related manner. Radiation induced meningioma has been reported in detail in the literature in patients who had been irradiated earlier in life. At the time of publication, there was no data on radiation exposure whilst in utero and meningioma. We report on a 42-year-old woman with multiple intracranial meningiomas and no other risk factors except a history of in utero exposure to low dose X-ray radiation at 12weeks gestational age.

Molecular Genetics of Intracranial Meningiomas with Emphasis on Canonical Wnt Signalling

Research over the last decade recognized the importance of novel molecular pathways in pathogenesis of intracranial meningiomas. In this review, we focus on human brain tumours meningiomas and the involvement of Wnt signalling pathway genes and proteins in this common brain tumour, describing their known functional effects. Meningiomas originate from the meningeal layers of the brain and the spinal cord. Most meningiomas have benign clinical behaviour and are classified as grade I by World Health Organization (WHO). However, up to 20% histologically classified as atypical (grade II) or anaplastic (grade III) are associated with higher recurrent rate and have overall less favourable clinical outcome. Recently, there is emerging evidence that multiple signalling pathways including Wnt pathway contribute to the formation and growth of meningiomas. In the review we present the synopsis on meningioma histopathology and genetics and discuss our research regarding Wnt in meningioma. Epithelial-to-mesenchymal transition, a process in which Wnt signalling plays an important role, is shortly discussed.

Secondary malignancy following radiotherapy for thyroid eye disease

AIM

To describe the first case of a secondary meningioma in a patient after radiation treatment for thyroid eye disease (TED). Secondarily to identify any additional cases of secondary malignancy resulting from radiotherapy for thyroid eye disease from our institutional experience.

BACKGROUND

Thyroid eye disease (TED) is a self-limiting auto-immune disorder causing expansion of orbital soft tissue from deposition of glycosaminoglycans and collagen, leading to significant cosmetic and functional morbidity. Established management options for TED include: glucocorticosteroids, orbital radiotherapy, and surgical orbital decompression. Two large series on radiotherapy for TED have been reported without any cases of secondary malignancy.

MATERIALS AND METHODS

The case of a patient with visual failure, found to have a sphenoid wing meningioma after previous TED radiotherapy is described. We then reviewed 575 patients with at least 3-year follow-up receiving radiotherapy for TED at British Columbia Cancer Agency to identify other possible secondary malignancies.

RESULTS

The patient had postoperative improvement in her vision without any identified complications. Three additional cases of hematologic malignancy were identified. The calculated risk in our population of developing a radiation-induced meningioma after TED with at least 3 years of follow-up of is 0.17% (1/575); with hematopoetic malignancies the risk for secondary malignancy is 0.7% (4/575).

CONCLUSIONS

Our calculated risk for secondary malignancy (0.17%, 0.7%) is similar to the reported theoretical risk published in the literature (0.3-1.2%). There is real risk for the development of a secondary malignancy after radiotherapy treatment of TED and treatment options should include consideration for this potential.

A retrospective analysis of meningioma in Central Texas

Documented meningioma cases in Central Texas (USA) from 1976 to 2013 were studied utilizing the Scott & White Brain Tumor Registry. All the cases examined were histologically diagnosed as meningiomas. Of the 372 cases, most were benign tumors (p < 0.05). A majority of the patients were females (p < 0.05). Elderly individuals (>45 years of age) superseded the younger patients in meningioma incidence (p < 0.05). Previous data regarding meningioma epidemiology in Texas showed a higher incidence in black patients when compared to white patients. By contrast, this study’s findings of Central Texas meningioma demographics show increased incidence of meningiomas in white patients (p < 0.05). This interesting find in meningioma prevalence warrants further investigation with a larger sample size, in order to establish validity and further parse out possible causes of meningioma development among white individuals.

Association of tamoxifen with meningioma: a population-based study in Sweden

Previous studies suggest that hormone therapy may play an important role in the development of meningioma. However, it is unclear whether medication with tamoxifen can prevent meningioma. Our study cohort included all women who were diagnosed with breast cancer between 1961 and 2010, and a total of 227 535 women were identified with breast cancer with a median age at diagnosis of 63 years. Women diagnosed with breast cancer after 1987 were defined as tamoxifen exposed; those diagnosed with breast cancer before or during 1987 were defined as not exposed to tamoxifen. Standardized incidence ratios (SIRs) were used to calculate the risk of subsequent meningioma. Of these women, 223 developed meningioma. For women without tamoxifen exposure, the risk of meningioma was significantly increased, with an SIR of 1.54 (95% confidence interval 1.30-1.81); the risk was not increased in those with tamoxifen exposure (SIR=1.06, 95% confidence interval 0.84-1.32). The increased risk of meningioma in women without tamoxifen exposure persisted during 10 years of follow-up. In this historical cohort study, we found that women diagnosed with breast cancer but not treated with tamoxifen had an increased incidence of meningioma, whereas the incidence was close to that of the general population in patients treated with tamoxifen. This suggests that tamoxifen may prevent the development of meningioma.

Epidemiology of meningiomas post-Public Law 107-206: The Benign Brain Tumor Cancer Registries Amendment Act

BACKGROUND

The current analysis follows the implementation of Public Law 107-260, the Benign Brain Tumor Cancer Registries Amendment Act, which mandated the collection of nonmalignant brain tumors.

METHODS

Meningiomas were selected from the Surveillance, Epidemiology, and End Results (SEER) Program database for the years 2004 to 2011. Demographic and clinical characteristics, initial treatment patterns, and survival outcomes were evaluated using surveillance epidemiology statistical methods.

RESULTS

The average annual age-adjusted incidence rate per 100,000 population was 7.62 (95 % confidence interval [CI], 7.55-7.68) for all meningiomas, 7.18 (95% CI, 7.12-7.25) for benign meningiomas, 0.32 (95% CI, 0.31-0.33) for borderline malignant meningiomas, and 0.12 (95% CI, 0.11-0.12) for malignant meningiomas. The annual rates increased for benign and borderline malignant tumors but decreased for malignant tumors. The rates for women exceeded those for men, especially for those with benign meningiomas. Black race was associated with significantly higher rates as was advancing age. Greater than 80% of tumors were located in cerebral meninges. Diagnostic confirmation through pathology occurred for approximately 50% of benign tumors, 90% of borderline malignant tumors, and 80% of malignant tumors. No initial treatment was reported for greater than 60% of benign tumors, 29% of borderline malignant tumors, or 31% of malignant tumors. The 5-year relative survival estimates for benign tumors, borderline malignant tumors, and malignant tumors were 85.6% (95% confidence interval [CI], 85%-86.2%), 82.3% (95% CI, 79.3%-84.8%), and 66% (95% CI, 60.6%-70.9%), respectively. Predictors of poorer survival were advanced age, being male gender, black race, no initial treatment, and malignant tumor behavior.

CONCLUSIONS

The current analysis demonstrates that there is an increasing incidence of nonmalignant meningiomas, probably because of reporting learning curves associated with the implementation of Public Law 107-260. The high proportion of cases who receive no initial treatment is a survival outcome concern, especially for patients with malignant meningiomas.

Brain tumors: Special characters for research and banking

A brain tumor is an intracranial neoplasm within the brain or in the central spinal canal. Primary malignant brain tumors affect about 200,000 people worldwide every year. Brain cells have special characters. Due to the specific properties of brain tumors, including epidemiology, growth, and division, investigation of brain tumors and the interpretation of results is not simple. Research to identify the genetic alterations of human tumors improves our knowledge of tumor biology, genetic interactions, progression, and preclinical therapeutic assessment. Obtaining data for prevention, diagnosis, and therapy requires sufficient samples, and brain tumors have a wide range. As a result, establishing the bank of brain tumors is very important and essential.

Merlin, the NF2 gene product

Merlin, the protein product of NF2 gene, is one of the most versatile tumor suppressors capable of integrating different mechanisms that regulate cell proliferation, motility, survival and signaling pathways underlying and governing those mechanisms. Merlin is considered a member of the band 4.1 families of cytoskeleton-associated proteins also called ERM family and acts as tumor suppressor. The main cause for transformation of Schwann cells into schwannomas is credited to the inactivation of the neurofibromin 2 (NF2) gene and the consecutive loss of its protein merlin. Recent scientific advances improved our understanding of pathogenic mechanisms involving NF2 gene. The present review brings genetic properties of NF2 gene, molecular characteristics of merlin, summarizes mutational spectra and explains merlin's multifunctional roles regarding its involvement in neurofibromatosis associated tumorigenesis.

The vitamin D receptor (VDR) gene polymorphisms in Turkish brain cancer patients

Objective. It has been stated that brain cancers are an increasingly serious issue in many parts of the world. The aim of our study was to determine a possible relationship between Vitamin D receptor (VDR) gene polymorphisms and the risk of glioma and meningioma. Methods. We investigated the VDR Taq-I and VDR Fok-I gene polymorphisms in 100 brain cancer patients (including 44 meningioma cases and 56 glioma cases) and 122 age-matched healthy control subjects. This study was performed by polymerase chain reaction-based restriction fragment length polymorphism (RF LP). Results. VDR Fok-I ff genotype was significantly increased in meningioma patients (15.9%) compared with controls (2.5%), and carriers of Fok-I ff genotype had a 6.47-fold increased risk for meningioma cases. There was no significant difference between patients and controls for VDR Taq-I genotypes and alleles. Conclusions. We suggest that VDR Fok-I genotypes might affect the development of meningioma.

μMLC-LINAC radiosurgery for intracranial meningiomas of complex shape

BACKGROUND

We present the long-term results of a consecutive series of patients with meningiomas treated by LINAC-radiosurgery using the micro-multi-leaf collimator technique (μMLC).

METHODS

Between May 2001 and July 2009, 78 patients (m: f = 024:54; median age, 56.8 years; range, 20.1-81 years) with 87 intracranial meningiomas (78 WHO I, seven WHO II, two WHO III) were treated with μMLC-LINAC radiosurgery at our institution, either as a primary or salvage treatment following one or more microsurgical procedures. Fifty-eight of 87 tumors (66.7%) were located in the skull base. The remaining 29 meningiomas (33.3%) were located in the convexity of the brain. The median tumor volume was 4.8 ml (range, 0.2-18.3 ml). The median tumor surface dose, maximal dose, and therapeutic isodose were 12 Gy, 16 Gy, and 75%, respectively.

RESULTS

For retrospective evaluation, we included 70 patients (78 tumors) with a minimum radiological follow-up of 24 months. After a median follow-up of 79.7 months (range, 24.2-109.1 months), 24 patients (34.3%) improved in their clinical status (paresis of N. abducens 18/48, facial paresis 4/8, and hemiparesis 2/9), 41 patients remained stable (58.6%), three patients had treatment-related temporary complaints (4.3%); two patients developed vertigo, and one had a left-sided hemihypesthesia. All complaints recovered completely after steroid medication within 2 weeks. Two patients (2.8%) developed permanent trigeminal neuralgia. Follow-up MR images showed a partial remission in 21 tumors (26.9%) and a stable tumor size in 55 cases (70.5%). Two patients with high-grade meningiomas showed a tumor progression (one WHO II and one WHO III meningioma). At the end of follow-up (July 2010), the actuarial 5- and 9-year progression-free survival after radiosurgery were 98 and 96%, respectively. There was no treatment-related mortality.

CONCLUSIONS

LINAC radiosurgery using a micro multi-leaf collimator for complex shaped intracranial meningiomas is effective yielding a high local tumor control, whereas the treatment-related morbidity remains low.

Family history of cancer in benign brain tumor subtypes versus gliomas

Purpose: Family history is associated with gliomas, but this association has not been established for benign brain tumors. Using information from newly diagnosed primary brain tumor patients, we describe patterns of family cancer histories in patients with benign brain tumors and compare those to patients with gliomas. Methods: Newly diagnosed primary brain tumor patients were identified as part of the Ohio Brain Tumor Study. Each patient was asked to participate in a telephone interview about personal medical history, family history of cancer, and other exposures. Information was available from 33 acoustic neuroma (65%), 78 meningioma (65%), 49 pituitary adenoma (73.1%), and 152 glioma patients (58.2%). The association between family history of cancer and each subtype was compared with gliomas using unconditional logistic regression models generating odds ratios (ORs) and 95% confidence intervals. Results: There was no significant difference in family history of cancer between patients with glioma and benign subtypes. Conclusion: The results suggest that benign brain tumor may have an association with family history of cancer. More studies are warranted to disentangle the potential genetic and/or environmental causes for these diseases.

Update on meningiomas

Although meningiomas are the most common tumor in the central nervous system, their incidence, epidemiology, and clinical outcomes have historically been poorly defined. This has been attributed to their benign course, difficulty obtaining histologic diagnosis, and lack of uniform database registration. Their clinical behavior can range from a silent incidentaloma to a lethal tumor. Projections of an aging population should raise medical awareness of an expectant rise in the incidence of meningiomas. This disease increases with advancing age, has a female predilection, and exposure to ionizing radiation is associated with a higher risk for disease development. There have been minimal advances in treatment, except in radiation therapy. Although no U.S. Food and Drug Administration-approved systemic therapy exists, there are treatment options that include hydroxyurea and sandostatin. Currently, no molecularly targeted therapy has provided clinical benefit, although recurring molecular alterations are present and novel therapies are being investigated.

Prevalence of previous extracranial malignancies in a series of 1228 patients presenting with meningioma

OBJECT

The study of patients with multiple neoplasms can yield valuable insight into the common pathogenesis of both diseases, as well as identify more subtle risk factors that might not be as readily apparent otherwise. The authors present an analysis of the prevalence of previously diagnosed extracranial malignancies at the time of meningioma diagnosis in 1228 patients evaluated at a single institution.

METHODS

All patients who underwent evaluation and/or treatment for meningioma between 1991 and 2007 at the authors' institution were identified. The intake history and physical were assessed for any history of extracranial malignancy. Using the National Cancer Institute data, the authors calculated an expected cancer prevalence for their meningioma patient population, and compared this derived value to the observed rate of these cancers in this population.

RESULTS

There were 1228 patients included in this study. A total of 50 patients (4.1%) with newly diagnosed meningioma had a history of an extracranial malignant tumor at the time of their initial meningioma diagnosis. In general, most malignancies did not differ in prevalence from their expected frequency in the population in the present study. Notable exceptions were acute leukemia (p < 0.0001), and papillary thyroid carcinoma, which had a prevalence 2.5 times that expected in this population (p < 0.05).

CONCLUSIONS

The data support a growing body of evidence suggesting an epidemiological link between papillary carcinoma of the thyroid and meningioma. Although the link between these tumors is not immediately apparent, it is possible that further exploration will yield interesting insight into the pathogenesis of both diseases.

[Epidemiology of primary brain tumor]

Two main approaches are generally used to study the epidemiology of primary brain tumors. The first approach is to identify risk factors, which may be intrinsic or related to external causes. The second main approach is descriptive. Intrinsic factors potentially affecting risk include genetic predisposition and susceptibility, gender, race, birth weight and allergy. Radiation exposure is the main extrinsic factor affecting risk. A large body of work devoted, among others, to electromagnetic fields and especially cellular phones, substitutive hormonal therapy, pesticides, and diet have been published. To date, results have been discordant. Descriptive epidemiological studies have reported an increasing annual incidence of primary brain tumors in industrialized countries. The main reasons are the increasing age of the population and better access to diagnostic imaging. Comparing incidences from one registry to another is difficult. Spatial and temporal variations constitute one explanation and evolutions in coding methods another. In all registries, weak incidence of primary brain tumors constitute a very important limiting factor. Renewed interest from the neuro-oncological community is needed to obtain pertinent and essential data which could facilitate improved knowledge on this topic.