Maternal and Perinatal Factors Associated With Childhood Brain Tumors: A Case-Control Study in Vietnam

INTRODUCTION

Brain cancer is the leading cause of cancer-related deaths in children and the majority of childhood brain tumors are diagnosed without determination of their underlying etiology. Little is known about risk factors for childhood brain tumors in Vietnam. The objective of this case-control study was to identify maternal and perinatal factors associated with brain tumors occurring in young Vietnamese children and adolescents.

METHODS

We conducted a hospital-based case-control study at Viet Duc University Hospital in Hanoi, Vietnam. Cases consisted of children with brain tumors aged 0-14 years old admitted to the hospital from January 2020 to July 2022 while the controls were age and sex-matched hospitalized children diagnosed with head trauma. Perinatal characteristics were abstracted from hospital medical records and maternal medical, behavioral, and sociodemographic factors were collected through in-person interviews. Conditional logistic regression models were used to examine maternal and perinatal factors associated with childhood brain tumors.

RESULTS

The study sample included 220 children (110 cases and 110 controls) whose average age was 8.9 years and 41.8% were girls. Children born to mothers aged greater than 30 years at the time of the child's birth had a higher risk of childhood brain tumors compared to those born to mothers aged from 18 to 30 years old (OR = 2.55; 95% CI: 1.13-5.75). Additionally low maternal body mass index prior to the current pregnancy of <18.5 kg/m2 significantly increased the odds of having a child with a brain tumor in relation to normal maternal body mass index from 18.5-22.9 kg/m2 (OR = 3.19; 95% CI: 1.36 - 7.50).

CONCLUSION

Advanced maternal age and being markedly underweight were associated with an increased odds of having a child with a brain tumor. A population-based study with larger sample size is needed to confirm and extend the present findings.

Clustering of Pediatric Brain Tumors in Texas, 2000-2017

Risk factors for pediatric brain tumors are largely unknown. Identifying spatial clusters of these rare tumors on the basis of residential address may provide insights into childhood socio-environmental factors that increase susceptibility. From 2000-2017, the Texas Cancer Registry recorded 4305 primary brain tumors diagnosed among children (≤19 years old). We performed a spatial analysis in SaTScan to identify neighborhoods (census tracts) where the observed number of pediatric brain tumors was higher than expected. Within each census tract, the number of pediatric brain tumors was summed on the basis of residential address at diagnosis. The population estimate from the 2007-2011 American Community Survey of 0- to 19-year-olds was used as the at-risk population. p-values were calculated using Monte Carlo hypothesis testing. The age-standardized rate was 54.3 per 1,000,000. SaTScan identified twenty clusters, of which two were statistically significant (p < 0.05). Some of the clusters identified in Texas spatially implicated potential sources of environmental risk factors (e.g., proximity to petroleum production processes) to explore in future research. This work provides hypothesis-generating data for further investigations of spatially relevant risk factors of pediatric brain tumors in Texas.

Childhood Brain Tumors: A Review of Strategies to Translate CNS Drug Delivery to Clinical Trials

Brain and spinal tumors affect 1 in 1000 people by 25 years of age, and have diverse histological, biological, anatomical and dissemination characteristics. A mortality of 30-40% means the majority are cured, although two-thirds have life-long disability, linked to accumulated brain injury that is acquired prior to diagnosis, and after surgery or chemo-radiotherapy. Only four drugs have been licensed globally for brain tumors in 40 years and only one for children. Most new cancer drugs in clinical trials do not cross the blood-brain barrier (BBB). Techniques to enhance brain tumor drug delivery are explored in this review, and cover those that augment penetration of the BBB, and those that bypass the BBB. Developing appropriate delivery techniques could improve patient outcomes by ensuring efficacious drug exposure to tumors (including those that are drug-resistant), reducing systemic toxicities and targeting leptomeningeal metastases. Together, this drug delivery strategy seeks to enhance the efficacy of new drugs and enable re-evaluation of existing drugs that might have previously failed because of inadequate delivery. A literature review of repurposed drugs is reported, and a range of preclinical brain tumor models available for translational development are explored.

Hormone replacement in survivors of childhood cancer and brain tumors: safety and controversies

Childhood cancer survivors are at risk for developing endocrine disorders, including deficits in growth hormone, thyroid hormone and sex hormones. The influence these hormones have on cell growth and metabolism has raised concerns regarding the safety of their use as treatments in survivors of childhood cancer and brain tumors. This article offers a summary of current knowledge, controversies and areas for future research pertaining to this area.

Acute Hematological Toxicity during Cranio-Spinal Proton Therapy in Pediatric Brain Embryonal Tumors

BACKGROUND

Embryonal tumors represent a heterogeneous entity of brain tumors that need a multidisciplinary treatment including cranio-spinal irradiation (CSI), with a known impact on the acute toxicity. Proton therapy (PT) boasts a reduction in acute hematological toxicity.

METHODS

We retrospectively examined 20 pediatric patients affected by high-risk medulloblastoma and other rare embryonal brain tumors subjected to CSI with PT from September 2016 to April 2020. Before CSI, all patients received induction chemotherapy, and three patients additionally received two high-dose courses with thiotepa, followed by an autologous haemopoietic stem cell transplantation. We recorded the total white blood cell count, absolute neutrophil count, platelets, and hemoglobin levels for all patients during PT.

RESULTS

Leucocytes and neutrophils decreased directly after the beginning of treatment, reaching a complete recovery at the end of treatment. Hemoglobin values remained constant over the treatment course. The median platelet value decreased until reaching a plateau around halfway through therapy, followed by a slow increase. No cases of febrile neutropenia or severe infections were reported. No treatment discontinuation due to hematological toxicity was necessary.

CONCLUSIONS

CSI with PT was proven to be safe in this setting of pediatric patients. Our study showed that despite all patients having undergone chemotherapy prior to irradiation, no serious hematological toxicity was reported at the end of the treatment with PT, and, therefore, no treatment was discontinued or delayed.

Follow-up evaluation of a web-based pediatric brain tumor board in Latin America

BACKGROUND

Since 2013, pediatric oncologists from Central and South America discuss neuro-oncology cases with experts from North America and Europe in a web-based "Latin American Tumor Board" (LATB). Here, we evaluate the feasibility of recommendations rendered by the Board.

METHODS

An electronic questionnaire was distributed to physicians who had received recommendations between October 2017 and October 2018. Physicians were asked regarding the feasibility of each recommendation given during the LATB discussion. Baseline case characteristics of all presented cases were obtained from anonymized minutes.

RESULTS

Of the 142 patients discussed, data on 103 patients from 15 countries were available, corresponding to 283 recommendations. Physicians followed 60% of diagnostic procedural recommendations and 69% of therapeutic recommendations. The most difficult recommendations to follow were genetic and molecular testing, pathology review, chemotherapy, surgery, and molecular targeted therapies. Histological diagnoses changed in eight of 18 cases in which a pathology review was undertaken. Fifty-four percent of the recommendations that could not be implemented were considered not feasible in the specific context of the patient, while 31% were not implemented due to a decision of the medical staff or the parents (15% not specified). However, 96% of respondents considered the recommendations useful.

CONCLUSION

Recommendations were frequently perceived as useful, and were applicable in the participating institutions. Nevertheless, limitations in availability of diagnostic procedures and treatment modalities affected the feasibility of some recommendations. Tele-oncology tumor boards offer physicians from low- and middle-income countries access to real-time, high-level subspecialist expertise and provide a valuable platform for worldwide information exchange.

Molecular-Targeted Therapy for Childhood Brain Tumors: A Moving Target

Molecular-targeted therapy is an attractive therapeutic approach for childhood brain tumors. Unfortunately, with some notable exceptions, such treatment has not yet made a major impact on survival or for that matter quality-of-life for children with brain tumors. Limitations include the specificity of any single agent to inhibit the target, the presence of multiple genetic abnormalities within a tumor, the likely presence of escape mechanisms and the frequent use of molecular-targeted therapies in relatively biologically unselected patient populations. Despite these limitations, the MEK inhibitors and the BRAF V600E inhibitors have already demonstrated efficacy and are being compared to standard therapy in trials of treatment-naïve patients. There is also great enthusiasm for molecular-targeted therapies that target selective gene fusions. Given the plasticity of epigenetic changes, the targeting of epigenetic aberrations is also a promising avenue of therapy. Because molecular-targeted therapies frequently target genes and pathways that are critical in normal brain development, the acute, subacute long-term sequelae of molecular-targeted therapies need to be carefully monitored.

Systematic review of the incidence and risk factors for cerebral vasculopathy and stroke after cranial proton and photon radiation for childhood brain tumors

Background

The aim of our study is to determine the incidence, timing, and risk factors for cerebral vasculopathy after cranial proton and photon radiation for pediatric brain tumors.

Methods

We performed a single-institution retrospective review of a cohort of children treated with proton radiation for brain tumors. MRA and/or MRI were reviewed for evidence of cerebral vascular stenosis and infarcts. Twenty-one similar studies (17 photon, 4 proton) were identified by systematic literature review.

Results

For 81 patients with median follow-up of 3 years, the rates of overall and severe vasculopathy were 9.9% and 6.2% respectively, occurring a median of 2 years post radiation. Dose to optic chiasm greater than 45 Gy and suprasellar location were significant risk factors. Results were consistent with 4 prior proton studies (752 patients) that reported incidence of 5% to 6.7%, 1.5 to 3 years post radiation. With significantly longer follow-up (3.7-19 years), 9 studies (1108 patients) with traditional photon radiation reported a higher rate (6.3%-20%) and longer time to vasculopathy (2-28 years). Significant risk factors were neurofibromatosis type 1 (NF-1; rate 7.6%-60%) and suprasellar tumors (9%-20%). In 10 studies with photon radiation (1708 patients), the stroke rate was 2% to 18.8% (2.3-24 years post radiation).

Conclusions

Childhood brain tumor survivors need screening for vasculopathy after cranial radiation, especially with higher dose to optic chiasm, NF-1, and suprasellar tumors. Prospective studies are needed to identify risk groups, and ideal modality and timing, for screening of this toxicity.

Parental occupational exposure to pesticides, animals and organic dust and risk of childhood leukemia and central nervous system tumors: Findings from the International Childhood Cancer Cohort Consortium (I4C)

Parental occupational exposures to pesticides, animals and organic dust have been associated with an increased risk of childhood cancer based mostly on case-control studies. We prospectively evaluated parental occupational exposures and risk of childhood leukemia and central nervous system (CNS) tumors in the International Childhood Cancer Cohort Consortium. We pooled data on 329,658 participants from birth cohorts in five countries (Australia, Denmark, Israel, Norway and United Kingdom). Parental occupational exposures during pregnancy were estimated by linking International Standard Classification of Occupations-1988 job codes to the ALOHA+ job exposure matrix. Risk of childhood (<15 years) acute lymphoblastic leukemia (ALL; n = 129), acute myeloid leukemia (AML; n = 31) and CNS tumors (n = 158) was estimated using Cox proportional hazards models to generate hazard ratios (HR) and 95% confidence intervals (CI). Paternal exposures to pesticides and animals were associated with increased risk of childhood AML (herbicides HR = 3.22, 95% CI = 0.97-10.68; insecticides HR = 2.86, 95% CI = 0.99-8.23; animals HR = 3.89, 95% CI = 1.18-12.90), but not ALL or CNS tumors. Paternal exposure to organic dust was positively associated with AML (HR = 2.38 95% CI = 1.12-5.07), inversely associated with ALL (HR = 0.55, 95% CI = 0.31-0.99) and not associated with CNS tumors. Low exposure prevalence precluded evaluation of maternal pesticide and animal exposures; we observed no significant associations with organic dust exposure. This first prospective analysis of pooled birth cohorts and parental occupational exposures provides evidence for paternal agricultural exposures as childhood AML risk factors. The different risks for childhood ALL associated with maternal and paternal organic dust exposures should be investigated further.

Chemical modulation of autophagy as an adjunct to chemotherapy in childhood and adolescent brain tumors

Brain tumors are the leading cause of cancer-related death in children and are the most challenging childhood cancer in relation to diagnosis, treatment, and outcome. One potential novel strategy to improve outcomes in cancer involves the manipulation of autophagy, a fundamental process in all cells. In cancer, autophagy can be thought of as having a "Janus"-like duality. On one face, especially in the early phases of cancer formation, autophagy can act as a cellular housekeeper to eliminate damaged organelles and recycle macromolecules, thus acting as tumor suppressor. On the other face, at later stages of tumor progression, autophagy can function as a pro-survival pathway in response to metabolic stresses such as nutrient depravation, hypoxia and indeed to chemotherapy itself, and can support cell growth by supplying much needed energy. In the context of chemotherapy, autophagy may, in some cases, mediate resistance to treatment. We present an overview of the relevance of autophagy in central nervous system tumors including how its chemical modulation can serve as a useful adjunct to chemotherapy, and use this knowledge to consider how targeting of autophagy may be relevant in pediatric brain tumors.

Health-related quality of life of adolescent and young adult survivors of childhood brain tumors

OBJECTIVE

Our aim was to expand research on predictors of health-related quality of life (HRQOL) for adolescent and young adult survivors of childhood brain tumors who are not living independently by evaluating the mediating role of family functioning in the association of disease severity/treatment late effects with survivor self-report and caregiver-proxy report of physical and emotional HRQOL.

METHODS

Mothers (N = 186) and their survivors living at home (N = 126) completed self-report and caregiver-proxy report of physical and emotional HRQOL. Mothers completed family functioning measures of general family functioning, caregiving demands, and caregiver distress. Medical file review and caregiver report were used to evaluate disease severity/treatment late effects.

RESULTS

Using structural equation models, family functioning was adjusted for sociodemographic factors. Disease severity/treatment late effects had significant direct effects on self-report and caregiver-proxy report of physical and emotional HRQOL. Family functioning had a significant direct effect on caregiver-proxy report of physical and emotional HRQOL, but these findings were not confirmed for self-report HRQOL. Model-fit indices suggested good fit of the models, but the mediation effect of family functioning was not supported.

CONCLUSIONS

Disease severity/treatment late effects explained self-report and caregiver-proxy report of physical and emotional HRQOL for these adolescent and young adult survivors of childhood brain tumors. Family functioning was implicated as an important factor for caregiver-proxy report only. To enhance physical and emotional HRQOL, findings underscore the importance of coordinated, multidisciplinary follow-up care for the survivors who are not living independently and their families to address treatment late effects and support family management.

Evolving of therapeutic strategies for CNS-PNET

BACKGROUND

A protocol for the intensive treatment of non-cerebellar PNET (CNS-PNET) combining chemotherapy and radiotherapy was launched in 2000. Efforts were subsequently made to improve the prognosis and to de-escalate the treatment for selected patient groups.

PROCEDURE

Twenty-eight consecutive patients were enrolled for a high-dose drug schedule (methotrexate, etoposide, cyclophosphamide, and carboplatin ± vincristine), followed by hyperfractionated accelerated CSI (HART-CSI) at total doses of 31-39 Gy, depending on the patient's age, with two high-dose thiotepa courses following CSI. After the first 15 patients had been treated, craniospinal irradiation (CSI) was replaced with focal radiotherapy (RT) for selected cases (non-metastatic and not progressing during induction chemotherapy). Eight of the 28 children received the same chemotherapy but conventionally fractionated focal RT at 54 Gy.

RESULTS

The 5-year progression-free survival (PFS), event-free survival (EFS), and overall survival (OS) rates were 62%, 53%, and 52%, respectively, for the whole series, and 70%, 70%, and 87% for the eight focally irradiated children. Residual disease and metastases were not prognostically significant. In children with residual disease, response to RT was significant (5-year PFS 59% vs. 20%, P = 0.01), while the total dose of CSI was not. There were three treatment-related toxic events. Relapses were local in seven cases (including two of the eight focally irradiated patients), and both local and disseminated in 2.

CONCLUSIONS

This intensive schedule enabled treatment stratification for the purposes of radiation, thereby sparing some children full-dose CSI. Local control is the main goal of treatment for CNS-PNET.

Trends in childhood brain tumor incidence, 1973-2009

In the mid-1980s, there was a rise in incidence rates of childhood brain tumors (CBT) in the United States that appeared to stabilize at a higher rate in the early 1990 s. An updated analysis of the pattern of CBT over the past 2 decades, with commentary on whether the elevated incidence rate has continued, is past due. We used Surveillance, Epidemiology and End Results (SEER) data to examine trends in incidence of CBT from 1973 through 2009. We examined age-adjusted incidence rates (AAIRs) and secular trends for all malignant brain tumors combined (SEER classification) by histologic tumor type and anatomic site. The incidence of CBT remained stable from 1987 to 2009 [annual percent change (APC) = 0.10; 95 % confidence intervals (CI) -0.39 to 0.61] with an AAIR for all CBT of 3.32 (95 % CI 3.22-3.42). The stability of rates in these two decades contrast the change that occurred in the mid-1980s (1983-1986), when the incidence of CBT increased by 53 % (APC = 14.06; 95 % CI 4.05-25.0). From 1983 to 1986, statistically significant rate increases were observed for pilocytic astrocytoma, PNET/medulloblastoma, and mixed glioma. Further, the rate of increase in pilocytic astrocytoma was similar to the rate of decrease for astrocytomas NOS from 1981 to 2009, suggesting a change from a more general to more specific classification. After the increase in rates in the mid-1980s, rates of CBT over the past two decades have stabilized. Changes in incidence rates of subtypes of tumors over this time period reflect changes both in classification of CBT and in diagnostic techniques.

Health-related quality of life and cognitive functioning at on- and off-treatment periods in children aged between 6-13 years old with brain tumors: a prospective longitudinal study

PURPOSE

Our study aimed to examine the relationship between intelligence and health-related quality of life (HRQOL) in children (6-13 years old) diagnosed as having a brain tumor.

MATERIALS AND METHODS

We administered a Korean version of the Wechsler Intelligence Scale for Children-III, the Pediatric Quality of Life Inventory, version 4.0 (PedsQL), the Korean version of the Parenting Stress Index-Short Form, and the Korean Version of the Parenting Sense of Competence (K-PSOC) scale before or after initial radiotherapy (T1) and after treatment termination (T2). In total, 13 patients completed both the T1 and T2 interviews.

RESULTS

Scores significantly declined between T1 and T2 on the full-scale intelligence quotients (FIQ), verbal intelligence quotients (VIQ), performance intelligence quotients (PIQ), similarity and coding tests, as well as the K-PSOC, which measures parental anxiety. FIQ scores at T1 were correlated with the self-reported PedsQL total scores (r=0.739) and the parent proxy-report PedsQL scores for school functioning (r=0.706) at T2. Also, the FIQ scores at T2 were correlated with the self-reported PedsQL total scores (r=0.748) and scores for physical health (r=0.728) at T2.

CONCLUSION

The cognitive ability and intelligence level of the patients significantly declined between on and off treatment periods, and higher intelligence functioning at both on and off treatment was correlated with long-term higher HRQOL. Further investigations that monitor intelligence, HRQOL and parenting stress over a longer period, using a greater number of participants, are needed.

Birth anomalies and obstetric history as risks for childhood tumors of the central nervous system

OBJECTIVE

The causes of childhood central nervous system (CNS) tumors are largely unknown. Birth characteristics have been examined as possible risk factors for childhood CNS tumors, although the studies have been underpowered and inconclusive. We hypothesized that birth anomalies and a mother's history of previous pregnancy losses, as a proxy for genetic defects, increase the risk for CNS tumors.

METHODS

From the California Cancer Registry, we identified 3733 patients aged 0 to 14 years with CNS tumors, diagnosed from 1988 through 2006 and linked to a California birth certificate. Four controls were matched to each patient. We calculated odds ratios (ORs) for the reported presence of a birth defect and for history of pregnancy losses by using logistic regression, adjusted for race, Hispanic ethnicity, maternal age, birth weight, and birth order.

RESULTS

Offspring from mothers who had ≥ 2 fetal losses after 20 weeks' gestation had a threefold risk for CNS tumors (OR: 3.13 [95% confidence interval (CI): 1.32-7.41]) and a 14-fold risk for high-grade glioma (OR: 14.28 [95% CI: 1.56-130.65]). Birth defects increased risk for the CNS cancers medulloblastoma (OR: 1.70 [95% CI: 1.12-2.57]), primitive neuroectodermal tumor (OR: 3.64 [95% CI: 1.54-8.56]), and germ cell tumors (OR: 6.40 [95% CI: 2.09-19.56]).

CONCLUSIONS

Multiple pregnancy losses after 20 weeks' gestation and birth defects increase the risk of a childhood CNS tumor. Previous pregnancy losses and birth defects may be surrogate markers for gene defects in developmental pathways that lead to CNS tumorigenesis.