Cigarette smoking and risk of meningioma: the effect of gender

Meningioma: International Consortium on Meningiomas consensus review on scientific advances and treatment paradigms for clinicians, researchers, and patients

Meningiomas are the most common primary intracranial tumors in adults and are increasing in incidence due to the aging population and increased access to neuroimaging. While most exhibit nonmalignant behavior, a subset of meningiomas are biologically aggressive and are associated with treatment resistance, resulting in significant neurologic morbidity and even mortality. In recent years, meaningful advances in our understanding of the biology of these tumors have led to the incorporation of molecular biomarkers into their grading and prognostication. However, unlike other central nervous system (CNS) tumors, a unified molecular taxonomy for meningiomas has not yet been established and remains an overarching goal of the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy-Not Official World Health Organization (cIMPACT-NOW) working group. Additionally, clinical equipoise still remains on how specific meningioma cases and patient populations should be optimally managed. To address these existing gaps, members of the International Consortium on Meningiomas including field-leading experts, have prepared this comprehensive consensus narrative review directed toward clinicians, researchers, and patients. Included in this manuscript are detailed overviews of proposed molecular classifications, novel biomarkers, contemporary treatment strategies, trials on systemic therapies, health-related quality-of-life studies, and management strategies for unique meningioma patient populations. In each section, we discuss the current state of knowledge as well as ongoing clinical and research challenges to road map future directions for further investigation.

Lifestyle and metabolic factors affect risk for meningioma in women: a prospective population-based study (The Cohort of Norway)

Background

Meningioma is the most common primary brain tumor, with a clear preponderance in women. Obesity is considered a risk factor for the development of meningioma. Obesity is also the clinical hallmark of metabolic syndrome, characterized by glucose intolerance, dyslipidemia, and hypertension. Lifestyle and metabolic factors directly impact overweight and obesity and are therefore potential risk factors for meningioma development. The aim of this study is to assess lifestyle and metabolic factors for meningioma risk in women.

Methods

The Cohort of Norway (CONOR) is a nationwide health survey, conducted between 1994 and 2003, including anthropometric measures, blood tests, and health questionnaires. Linkage to the National Cancer Registry enabled the identification of intracranial meningioma during follow-up until December 2018.

Results

A total of 81,652 women were followed for a combined total of 1.5 million years, and 238 intracranial meningiomas were identified. Increasing levels of physical activity (HR 0.81; 95% CI 0.68-0.96; p trend <0.02) and parity (HR 0.83; 95% CI 0.71-0.97; p trend <0.03) were negatively associated with meningioma risk. Diabetes mellitus or glucose intolerance increased the risk for meningioma (HR 2.54; 95% CI 1.60-4.05). Overweight and obesity were not associated with meningioma risk, nor was metabolic syndrome. However, participants without metabolic dysfunction had a reduced meningioma risk, while participants with all five metabolic factors present had a 4-fold risk increase for meningioma (HR 4.28; 95% CI 1.34-13.68).

Conclusion

Lifestyle factors seem to significantly influence meningioma risk. However, disentangling the complex associations and interactions between factors for meningioma risk will be a challenging task for future studies.

Elevated meningioma risk among individuals who are Non-Hispanic Black is strongest for grade 2-3 tumors and synergistically modified by male sex

Background

Meningioma risk factors include older age, female sex, and African-American race. There are limited data exploring how meningioma risk in African-Americans varies across the lifespan, interacts with sex, and differs by tumor grade.

Methods

The Central Brain Tumor Registry of the United States (CBTRUS) is a population-based registry covering the entire U.S. population. Meningioma diagnoses from 2004-2019 were used to calculate incidence rate ratios (IRRs) for non-Hispanic Black individuals (NHB) compared to non-Hispanic white individuals (NHW) across 10-year age intervals, and stratified by sex and by WHO tumor grade.

Results

53,890 NHB individuals and 322,373 NHW individuals with an intracranial meningioma diagnosis were included in analyses. Beginning in young adulthood, the NHB-to-NHW IRR was elevated for both grade 1 and grade 2/3 tumors. The IRR peaked in the seventh decade of life regardless of grade, and was higher for grade 2/3 tumors (IRR=1.57; 95% CI: 1.46-1.69) than grade 1 tumors (IRR=1.27; 95% CI: 1.25-1.30) in this age group. The NHB-to-NHW IRR was elevated in females (IRR=1.17; 95% CI: 1.16-1.18) and further elevated in males (IRR=1.28; 95% CI: 1.26-1.30), revealing synergistic interaction between NHB race/ethnicity and male sex (P Interaction =0.001).

Conclusions

Relative to NHW individuals, NHB individuals are at elevated risk of meningioma from young adulthood through old age. NHB race/ethnicity conferred higher risk of meningioma among men than women, and higher risk of developing WHO grade 2/3 tumors. Results identify meningioma as a significant source of racial disparities in neuro-oncology and may help to improve preoperative predictions of meningioma grade.

Early Preventive Strategies and CNS Meningioma - Is This Feasible? A Comprehensive Review of the Literature

BACKGROUND

Meningiomas are one of the most common benign primary brain tumors; however, there is a paucity of literature on potential preventability. This comprehensive review aimed to explore the existing evidence for the potential risk factors that may contribute to meningioma development and to discuss early prevention strategies.

METHODS

Literature search was conducted via MEDLINE, Embase, Web of Science, and Cochrane Database to retrieve existing literature on various environmental exposures and lifestyle behaviors that are potential risk factors for the development of meningiomas.

RESULTS

Significant risk factors included exposure to ionizing radiation and certain environmental chemicals. Notably, this study also identified that cigarette smoking and obesity are associated with the development of meningiomas. To date, wireless phone usage, hormonal exposures, dietary factors, and traumatic brain injury remain inconclusive. Early prevention strategies should primarily be family-driven, community-based, and public health-endorsed strategies. Targeting unhealthy behaviors through healthcare organizations could execute a pivotal role in the maintenance of an optimum lifestyle, reducing the development of risk factors pertinent to meningiomas.

CONCLUSIONS

To our knowledge, this is the first study that offers a perspective on prevention of meningiomas. A causal relationship of risk factors in developing meningiomas cannot be directly established with the current evidence. We are aware of the limitations of the hypothesis, but we believe that this study will raise more awareness and our findings could potentially be endorsed by organizations promoting health across the globe. Further prospective and retrospective studies will shed more light on this topic and help establish a definitive relationship.

Identifying brain tumor patients' subtypes based on pre-diagnostic history and clinical characteristics: a pilot hierarchical clustering and association analysis

Introduction

Central nervous system (CNS) tumors are severe health conditions with increasing incidence in the last years. Different biological, environmental and clinical factors are thought to have an important role in their epidemiology, which however remains unclear.

Objective

The aim of this pilot study was to identify CNS tumor patients' subtypes based on this information and to test associations with tumor malignancy.

Methods

90 patients with suspected diagnosis of CNS tumor were recruited by the Neurosurgery Unit of IRCCS Neuromed. Patients underwent anamnestic and clinical assessment, to ascertain known or suspected risk factors including lifestyle, socioeconomic, clinical and psychometric characteristics. We applied a hierarchical clustering analysis to these exposures to identify potential groups of patients with a similar risk pattern and tested whether these clusters associated with brain tumor malignancy.

Results

Out of 67 patients with a confirmed CNS tumor diagnosis, we identified 28 non-malignant and 39 malignant tumor cases. These subtypes showed significant differences in terms of gender (with men more frequently presenting a diagnosis of cancer; p = 6.0 ×10-3) and yearly household income (with non-malignant tumor patients more frequently earning ≥25k Euros/year; p = 3.4×10-3). Cluster analysis revealed the presence of two clusters of patients: one (N=41) with more professionally active, educated, wealthier and healthier patients, and the other one with mostly retired and less healthy men, with a higher frequency of smokers, personal history of cardiovascular disease and cancer familiarity, a mostly sedentary lifestyle and generally lower income, education and cognitive performance. The former cluster showed a protective association with the malignancy of the disease, with a 74 (14-93) % reduction in the prevalent risk of CNS malignant tumors, compared to the other cluster (p=0.026).

Discussion

These preliminary data suggest that patients' profiling through unsupervised machine learning approaches may somehow help predicting the risk of being affected by a malignant form. If confirmed by further analyses in larger independent cohorts, these findings may be useful to create potential intelligent ranking systems for treatment priority, overcoming the lack of histopathological information and molecular diagnosis of the tumor, which are typically not available until the time of surgery.

Integrated clinical genomic analysis reveals xenobiotic metabolic genes are downregulated in meningiomas of current smokers

INTRODUCTION

Meningiomas are the most common primary intracranial tumor. Recently, various genetic classification systems for meningioma have been described. We sought to identify clinical drivers of different molecular changes in meningioma. As such, clinical and genomic consequences of smoking in patients with meningiomas remain unexplored.

METHODS

88 tumor samples were analyzed in this study. Whole exome sequencing (WES) was used to assess somatic mutation burden. RNA sequencing data was used to identify differentially expressed genes (DEG) and genes sets (GSEA).

RESULTS

Fifty-seven patients had no history of smoking, twenty-two were past smokers, and nine were current smokers. The clinical data showed no major differences in natural history across smoking status. WES revealed absence of AKT1 mutation rate in current or past smokers compared to non-smokers (p = 0.046). Current smokers had increased mutation rate in NOTCH2 compared to past and never smokers (p < 0.05). Mutational signature from current and past smokers showed disrupted DNA mismatch repair (cosine-similarity = 0.759 and 0.783). DEG analysis revealed the xenobiotic metabolic genes UGT2A1 and UGT2A2 were both significantly downregulated in current smokers compared to past (Log2FC = - 3.97, padj = 0.0347 and Log2FC = - 4.18, padj = 0.0304) and never smokers (Log2FC = - 3.86, padj = 0.0235 and Log2FC = - 4.20, padj = 0.0149). GSEA analysis of current smokers showed downregulation of xenobiotic metabolism and enrichment for G2M checkpoint, E2F targets, and mitotic spindle compared to past and never smokers (FDR < 25% each).

CONCLUSION

In this study, we conducted a comparative analysis of meningioma patients based on their smoking history, examining both their clinical trajectories and molecular changes. Meningiomas from current smokers were more likely to harbor NOTCH2 mutations, and AKT1 mutations were absent in current or past smokers. Moreover, both current and past smokers exhibited a mutational signature associated with DNA mismatch repair. Meningiomas from current smokers demonstrate downregulation of xenobiotic metabolic enzymes UGT2A1 and UGT2A2, which are downregulated in other smoking related cancers. Furthermore, current smokers exhibited downregulation xenobiotic metabolic gene sets, as well as enrichment in gene sets related to mitotic spindle, E2F targets, and G2M checkpoint, which are hallmark pathways involved in cell division and DNA replication control. In aggregate, our results demonstrate novel alterations in meningioma molecular biology in response to systemic carcinogens.

Peritumoral Brain Edema in Relation to Tumor Size Is a Variable That Influences the Risk of Recurrence in Intracranial Meningiomas

Peritumoral brain edema (PBE) is common in intracranial meningiomas (IM) and can increase their morbidity. It is not uncommon for a neurosurgeon to confront meningiomas with a large proportion of PBE independently from the site and size of the contrast-enhancing lesion with increased surgical risks. We performed a retrospective review of 216 surgically-treated patients suffering from IM. We recorded clinical, biological, and radiological data based on the rate of tumor and edema volume and divided the patients into a group with high Edema/Tumor ratio and a group with a low ratio. We investigated how the ratio of edema/lesion may affect the outcome. Multivariate analysis was performed for the two groups. Smokers were found to be more likely to belong to the high-rate group. The edema/tumor ratio did not affect the surgical radicality; however, independently of the biological sub-type, WHO grading, and EOR, a higher frequency of recurrence is shown in patients with a high edema/tumor ratio (70.5% vs. 8.4%. p < 0.01). There is evidence to suggest that the blood-brain barrier (BBB) damage from smoke could play a role in an increased volume of PBE. The present study demonstrates that IMs showing a high PBE ratio to tumor volume at diagnosis are associated with a smoking habit and a higher incidence of recurrence independently of their biological type and grading.

The impact of body mass index and height on risk for primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves in 1.7 million norwegian women and men: a prospective cohort study

BACKGROUND

Primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves comprise a heterogenous group of pathology, dominantly represented by meningioma, nerve sheath tumours (NST) and glioma. Body height and body mass index (BMI) are risk factors for certain brain tumour subgroups, but no other study has specifically assessed height and BMI in relation to primary tumours of the spine and peripheral nerves in women and men.

METHODS

In this prospective population-based cohort study height and weight were measured in 1.7 million adult Norwegian women and men at baseline. Incident cases of primary tumours arising from the spinal cord, spinal meninges, spinal and peripheral nerves during follow-up were identified by linkage to the National Cancer Registry. Tumour risk was assessed by Cox regression analyses in relation to height and BMI.

RESULTS

During 49 million person-years of follow-up, 857 primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves were identified. Overweight and obesity were not associated with risk for all tumours or any tumour subgroup. Height was positively associated with risk for all tumours (HR per 10 cm increase: 1.30, 95% CI 1.16-1.46). The association between height and tumour risk varied between tumour subgroups: while height was not significantly associated with NST, height increased the risk for meningioma (HR 1.42, 95% CI 1.13-1.78) and glioma (HR 1.56, 95% CI 1.06-2.28). The strongest association between height and tumour risk was found for the glioma subgroup of ependymoma in women (HR 3.38, 95% CI 1.64-6.94).

CONCLUSION

This study could not identify overweight and obesity as risk factors for primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves in women or men. Increasing body height was associated with increased tumour risk overall, but not universal for all tumour subgroups.Importance of the studyPrimary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves have received little focus in epidemiologic studies, although the incidence and histo-pathological tumour subgroups differ significantly from primary brain tumours. Risk factors for these tumours have hardly been assessed in previous studies. Height, overweight and obesity are known risk factors for several cancers, including certain brain tumour subgroups, such as meningioma.This is the first study to report the association between height, overweight and obesity and primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves. This includes tumour subgroups of meningioma, nerve sheath tumour, glioma and the most common spinal glioma subgroup of ependymoma. While overweight and obesity were not associated with either of the tumour subgroups, an association between increasing body height and risk for spinal meningioma and glioma, including ependymoma, was found. Nerve sheath tumour risk was not associated with increasing body height.

A decreased risk of meningioma in women smokers was only observed in American studies rather than studies conducted in other countries: a systematic review and meta-analysis

Background

Whether smoking is related to a decreased risk of meningioma in women is still controversial. We conducted a systematic review and meta-analysis examining the association between smoking and risk of meningiomas in women.

Methods

Two authors independently performed a systematic literature review in the PubMed, Cochrane Library, and EMBASE databases. We identified case-control and cohort studies quantifying associations between smoking and risk of meningioma in women. A meta-analysis by pooling studies was performed according to the multivariate-adjusted risk estimates and 95% confidence intervals (CIs) preferentially. We further conducted additional subgroup and sensitivity analyses to explore possible explanations of the results.

Results

A total of seven observational studies were included, with a total of 2132 female patients diagnosed with meningiomas. Ever smoking was associated with a significantly reduced risk of meningioma in women, with pooled odds ratio (OR) of 0.83 (95% CI 0.70–0.98). Similar findings were noted for current (OR 0.78, 95% CI 0.66–0.93) and past (OR 0.82, 95% CI 0.71–0.94) smokers. However, considering the areas, the OR of ever smoking was 0.77 (95% CI 0.68–0.87) in three American studies, but 0.99 (95% CI 0.73–1.35) in four studies conducted in other countries.

Conclusions

Based on limited epidemiological evidence, a decreased risk of meningioma in women smokers was only observed in American studies rather than studies conducted in other countries.

A meta-analysis of active smoking and risk of meningioma

INTRODUCTION

Cigarette smoking has been hypothesized to be a risk factor for meningioma. However, the results of studies exploring the relationship between smoking exposure and the occurrence of meningioma are inconsistent.

METHODS

A search of PubMed, Medline, Embase, and Science Direct (up to June 2020) databases was performed. Two authors independently extracted the data. The Newcastle–Ottawa Scale was employed for judging the quality of articles. A random-effects model was utilized for meta-analysis. Association analysis between smoking and meningioma was based on the adjusted RR and the 95% CI, as reported by eligible studies. Subgroup and sensitivity analyses were performed and publication bias was assessed. Subgroup analysis was conducted by geographical region, study design, sex, study quality, and adjustments of RR score. Begg’s and Egger’s tests were employed for detecting publication bias.

RESULTS

Twelve articles, including 2 cohort studies and 10 case–control studies, and a total of 1210167 participants were identified. The pooled relative risk (RR) with 95% confidence interval (95% CI) implied that smoking was not associated with increased risk of meningioma in men and women combined (RR=1.09; 95% CI: 0.90–1.33). From the sex-stratified subgroup analysis, the risk of meningioma was significant in men (RR=1.42; 95% CI: 1.16–1.74). Risk of meningioma in women did not remain significant (RR=0.92; 95% CI: 0.73–1.16). There was a high heterogeneity in the results (I²=58.4%, p=0.002). Sensitivity analyses showed stable results and there was no evidence of publication bias.

CONCLUSIONS

Cigarette smoking is not associated with a significantly increased risk of meningioma in the whole population, but there is a positive association in men but not in women.

Epidemiology of meningiomas

More than 70,000 primary central nervous system tumors are diagnosed in the United States each year. Approximately 36% of these are meningiomas, making it the most common primary brain tumor. Because meningioma risk increases dramatically with age, the healthcare burden of meningioma in the developed world will continue to rise as demographics shift toward an older population. In addition to demographic factors associated with increased meningioma risk (i.e., older age, female sex, African American ethnicity), increased body mass index is a strong risk factor. A history of atopic allergies, eczema, and increased serum IgE are all consistently associated with reduced meningioma risk, suggesting a potential role for immunosurveillance. Although ionizing radiation is a strong meningioma risk factor, it accounts for very few cases at the population level. Recent studies suggest that diagnostic radiation (e.g., dental X-rays) increases meningioma risk. Because radiation dosages associated with medical imaging have decreased dramatically, the public health impact of this exposure is likely in decline. Genome-wide association studies have identified common inherited variants in the gene MLLT10 and RIC8A as low-penetrance meningioma risk alleles. To provide further insight into the etiology of meningioma, future studies will need to simultaneously examine genetic and environmental risk factors, while also stratifying analyses by subject sex.

Risk factors for childhood and adult primary brain tumors

Primary brain tumors account for ~1% of new cancer cases and ~2% of cancer deaths in the United States; however, they are the most commonly occurring solid tumors in children. These tumors are very heterogeneous and can be broadly classified into malignant and benign (or non-malignant), and specific histologies vary in frequency by age, sex, and race/ethnicity. Epidemiological studies have explored numerous potential risk factors, and thus far the only validated associations for brain tumors are ionizing radiation (which increases risk in both adults and children) and history of allergies (which decreases risk in adults). Studies of genetic risk factors have identified 32 germline variants associated with increased risk for these tumors in adults (25 in glioma, 2 in meningioma, 3 in pituitary adenoma, and 2 in primary CNS lymphoma), and further studies are currently under way for other histologic subtypes, as well as for various childhood brain tumors. While identifying risk factors for these tumors is difficult due to their rarity, many existing datasets can be leveraged for future discoveries in multi-institutional collaborations. Many institutions are continuing to develop large clinical databases including pre-diagnostic risk factor data, and developments in molecular characterization of tumor subtypes continue to allow for investigation of more refined phenotypes. Key Point 1. Brain tumors are a heterogeneous group of tumors that vary significantly in incidence by age, sex, and race/ethnicity.2. The only well-validated risk factors for brain tumors are ionizing radiation (which increases risk in adults and children) and history of allergies (which decreases risk).3. Genome-wide association studies have identified 32 histology-specific inherited genetic variants associated with increased risk of these tumors.

Long-Term Use of Tamoxifen Is Associated With a Decreased Subsequent Meningioma Risk in Patients With Breast Cancer: A Nationwide Population-Based Cohort Study

Background: Earlier studies have indicated a relatively higher risk of occurring meningioma among female breast cancer survivors and have suggested that tamoxifen might decrease this risk. The present study evaluated whether tamoxifen use in breast cancer patients can reduce the risk of meningioma.

Methods: We designed a population-based cohort study by using data from the National Health Insurance system of Taiwan to assess this issue. Between January 1, 2000, and December 31, 2008, women with breast cancer and of age ≥20 years were included. They were divided into two groups: those who had not received tamoxifen therapy and those who had. The Cox’s proportion hazard regression analysis was conducted to estimate the effects of tamoxifen treatment and the subsequent meningioma risk.

Results: We identified a total of 50,442 tamoxifen users and 30,929 non-tamoxifen users. Tamoxifen users had a borderline significantly lower overall risk of meningioma than non-tamoxifen users [adjusted hazard ratio (aHR) = 0.64, 95% confidence interval (95% CI) = 0.40–1.02]. A statistically significant difference was found in those patients with tamoxifen treatment duration longer than 1,500 days (aHR = 0.42, 95% CI = 0.19–0.91) or with cumulative dosage exceeding 26,320 mg (aHR = 0.44, 95% CI = 0.22–0.88). Furthermore, no statistically significant joint effect of aromatase inhibitors and tamoxifen on the occurrence of meningioma among breast cancer patients was seen.

Conclusion: Tamoxifen users had a non-significantly (36%) lower risk of developing meningioma than did tamoxifen non-users; however, our data indicated that tamoxifen therapy is associated with a reduced meningioma risk for Taiwanese breast cancer patients receiving long duration or high cumulative dosage treatment with tamoxifen.

Smoking and Glioma Risk: Evidence From a Meta-Analysis of 25 Observational Studies

To systematically assess the relationship between smoking and glioma risk.A dose-response meta-analysis of case-control and cohort studies was performed. Pertinent studies were identified by searching database and reference lists. Random-effects model was employed to pool the estimates of the relative risks (RRs) with corresponding 95% confidence intervals (CIs).A total of 19 case-control and 6 cohort studies were included. Overall, compared with those who never smoked, the pooled RR and 95% CI was 0.98 (0.92-1.05) for ever smoker. The subgroups were not significantly different regarding risk of glioma except the group of age at start smoking (RR = 1.17, 95% CI: 0.93-1.48 for age < 20; RR = 1.25, 95% CI: 1.02-1.52 for age ≥ 20). Dose-response analysis also suggested no significant association between smoking and the risk of glioma, although some evidence for a linear relationship between smoking and glioma risk was observed.In conclusion, this meta-analysis provides little support for a causal relationship between smoking and risk of glioma.

Birth desires and intentions of women diagnosed with a meningioma

OBJECT To the authors' knowledge, no previous study has examined the impact of meningioma diagnosis on women's birth desires and intentions. In an exploratory study, the authors surveyed women affected by meningioma to determine their attitudes toward childbearing and the influences, including physician recommendations, on this major life decision and compared their responses to those of women in the general population. METHODS Meningioma survivors from the Meningioma Mommas online support group participated in an online survey that included questions on their birth desires and intentions, whether the risk of disease recurrence influenced their reproductive decisions, and risks communicated to them by their physicians. Using chi-square and rank-sum tests, the authors compared the survey participants' responses with those of the general population as assessed by the 2006-2010 National Survey of Family Growth. Logistic regression was used to adjust for differences in age, race, ethnicity, education, parity, pregnancy status, and infertility status in these populations. RESULTS Respondents with meningioma were more likely than those in the general population to report wanting a baby (70% vs 54%, respectively), intending to have a baby (27% vs 12%, respectively), and being very sure about this intention (10% vs 2%, respectively). More than half (32 of 61) of the women of childbearing age reported being advised by a physician about potential risk factors for recurrence of the meningioma, and pregnancy was the most commonly cited risk factor (26 of 61). The most common factor influencing birth desires and intentions was risk of the meningioma returning and requiring more treatment, which was reported by nearly two-thirds of the women in their childbearing years. CONCLUSIONS A majority of the meningioma survivors of childbearing age who completed the survey reported a desire for children, although concern about the risk of meningioma recurrence was an important factor for these women when making reproductive decisions. Physicians are in a position to educate their patients on potential risk factors for recurrence and to provide contact information for services such as counseling and family planning.

Endogenous and exogenous hormone exposure and the risk of meningioma in men

OBJECT

Meningioma is a disease with considerable morbidity and is more commonly diagnosed in females than in males. Hormonally related risk factors have long been postulated to be associated with meningioma risk, but no examination of these factors has been undertaken in males.

METHODS

Subjects were male patients with intracranial meningioma (n = 456), ranging in age from 20 to 79 years, who were diagnosed among residents of the states of Connecticut, Massachusetts, and North Carolina, the San Francisco Bay Area, and 8 counties in Texas and matched controls (n = 452). Multivariate logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for the association between hormonal factors and meningioma risk in men.

RESULTS

Use of soy and tofu products was inversely associated with meningioma risk (OR 0.50 [95% CI 0.37-0.68]). Increased body mass index (BMI) appears to be associated with an approximately 2-fold increased risk of developing meningioma in men. No other single hormone-related exposure was found to be associated with meningioma risk, although the prevalence of exposure to factors such as orchiectomy and vasectomy was very low.

CONCLUSIONS

Estrogen-like exogenous exposures, such as soy and tofu, may be associated with reduced risk of meningioma in men. Endogenous estrogen-associated factors such as high BMI may increase risk. Examination of other exposures related to these factors may lead to better understanding of mechanisms and potentially to intervention.

Exogenous hormone use, reproductive factors, and risk of intracranial meningioma in females

OBJECT

The 2-fold higher incidence of meningioma in women compared with men has long suggested a role for hormonally mediated risk factors, but specific mechanisms remain elusive.

METHODS

The study included data obtained in 1127 women 29-79 years of age with intracranial meningioma diagnosed among residents of Connecticut, Massachusetts, North Carolina, the San Francisco Bay Area, and 8 Texas counties between May 1, 2006, and October 6, 2011, and data obtained in 1092 control individuals who were frequency matched for age group and geography with meningioma patients.

RESULTS

No association was observed for age at menarche, age at menopause, or parity and meningioma risk. Women who reported breastfeeding for at least 6 months were at reduced risk of meningioma (OR 0.78, 95% CI 0.63-0.96). A significant positive association existed between meningioma risk and increased body mass index (p < 0.01) while a significant negative association existed between meningioma risk and current smoking (p < 0.01). Among premenopausal women, current use of oral contraceptives was associated with an increased risk of meningiomas (OR 1.8, 95% CI 1.1-2.9), while current use of hormone replacement therapy among postmenopausal women was not associated with a significant elevation in risk (OR 1.1, 95% CI 0.74-1.67). There was no association between use of fertility medications and meningioma risk.

CONCLUSIONS

The authors' study confirms associations for body mass index, breastfeeding, and cigarette smoking but provides little evidence for associations of reproductive and menstrual factors with meningioma risk. The relationship between current use of exogenous hormones and meningioma remains unclear, limited by the small numbers of patients currently on oral hormone medications and a lack of hormone receptor data for meningioma tumors.