Neighborhood deprivation index is associated with weight status among long-term survivors of childhood acute lymphoblastic leukemia

PURPOSE

Area deprivation index (ADI), a measure of neighborhood socioeconomic disadvantage, has been linked to metabolic outcomes in the general population but has received limited attention in survivors of childhood acute lymphoblastic leukemia (ALL), a population with high rates of overweight and obesity.

METHODS

We retrospectively reviewed heights and weights of ≥ 5 year survivors of pediatric ALL (diagnosed 1990-2013). Residential addresses were geocoded using ArcGIS to assign quartiles of ADI, a composite of 17 measures of poverty, housing, employment, and education, with higher quartiles reflecting greater deprivation. Odds ratios (OR) and 95% confidence intervals (CI) for the association between ADI quartiles and overweight/obesity or obesity alone were calculated with logistic regression.

RESULTS

On average, participants (n = 454, 50.4% male, 45.2% Hispanic) were age 5.5 years at diagnosis and 17.4 years at follow-up. At follow-up, 26.4% were overweight and 24.4% obese. Compared to the lowest ADI quartile, survivors in the highest quartile were more likely to be overweight/obese at follow-up (OR = 2.33, 95% CI: 1.23-4.44) after adjusting for race/ethnicity, sex, age at diagnosis, and age at follow-up. The highest ADI quartile remained significantly associated with obesity (OR = 5.28, 95% CI: 1.79-15.54) after accounting for weight status at diagnosis.

CONCLUSIONS

This study provides novel insights into possible social determinants of health inequalities among survivors of childhood ALL by reporting a significant association between neighborhood deprivation and overweight/obesity.

IMPLICATIONS FOR CANCER SURVIVORS

Survivors of childhood ALL residing in neighborhood with greater socioeconomic disadvantage may be at increased risk of overweight and obesity and candidates for targeted interventions.

Genetic variation in the body mass index of adult survivors of childhood acute lymphoblastic leukemia: A report from the Childhood Cancer Survivor Study and the St. Jude Lifetime Cohort

BACKGROUND

Treatment characteristics such as cranial radiation therapy (CRT) do not fully explain adiposity risk in childhood acute lymphoblastic leukemia (ALL) survivors. This study was aimed at characterizing genetic variation related to adult body mass index (BMI) among survivors of childhood ALL.

METHODS

Genetic associations of BMI among 1458 adult survivors of childhood ALL (median time from diagnosis, 20 years) were analyzed by multiple approaches. A 2-stage genome-wide association study in the Childhood Cancer Survivor Study (CCSS) and the St. Jude Lifetime Cohort Study (SJLIFE) was performed. BMI was a highly polygenic trait in the general population. Within the known loci, the BMI percent variance explained was estimated, and additive interactions (chi-square test) with CRT in the CCSS were evaluated. The role of DNA methylation in CRT interaction was further evaluated in a subsample of ALL survivors.

RESULTS

In a meta-analysis of the CCSS and SJLIFE, 2 novel loci associated with adult BMI among survivors of childhood ALL (LINC00856 rs575792008 and EMR1 rs62123082; P_Meta < 5E-8) were identified. It was estimated that the more than 700 known loci explained 6.2% of the variation in adult BMI in childhood ALL survivors. Within the known loci, significant main effects for 23 loci and statistical interactions with CRT at 9 loci (P < 7.0E-5) were further identified. At 2 CRT-interacting loci, DNA methylation patterns may have differed by age.

CONCLUSIONS

Adult survivors of childhood ALL have genetic heritability for BMI similar to that observed in the general population. This study provides evidence that treatment with CRT can modify the effect of genetic variants on adult BMI in childhood ALL survivors.

Early evidence of pulmonary dysfunction in survivors of childhood Hodgkin lymphoma

Survivors of childhood Hodgkin lymphoma (HL) are at risk for pulmonary late effects, but whether survivors also experience pulmonary dysfunction early off therapy is not well understood. We determined the incidence of pulmonary dysfunction in children/adolescents with HL at entry into survivorship, as well as risk factors related to this outcome. Survivors in clinical remission and with a pulmonary function test (PFT) obtained 2-6 years off therapy were included. Seventy-five of 118 subjects met eligibility criteria (mean age at diagnosis: 13 years, mean time off therapy: 40 months). Survivors of HL had a higher than expected incidence of pulmonary dysfunction at entry into survivorship (40/75 [53%] had an abnormal DLCO and/or a restrictive or obstructive impairment). Evidence for diffusion impairment was associated with female sex (odds ratio [OR] = 3.19, p = .04). Longitudinal follow-up studies are needed to determine if early evidence of pulmonary dysfunction predicts risk for later onset pulmonary outcomes.

β-Cell and renal transplantation options for diabetes

Despite major advances in structured education, insulin delivery and glucose monitoring, diabetes self-management remains an unremitting challenge. Insulin therapy is inextricably linked to risk of dangerous hypoglycaemia and sustained hyperglycaemia remains a leading cause of renal failure. This review sets out to demystify transplantation for diabetes multidisciplinary teams, facilitating consideration and incorporation within holistic overall person-centred management. Deceased and living donor kidney, whole pancreas and isolated islet transplant procedures, indications and potential benefits are described, in addition to outcomes within the integrated UK transplant programme.

Utilization of archived neonatal dried blood spots for genome-wide genotyping

Introduction

Heel pricks are performed on newborns for diagnostic screenings of various pre-symptomatic metabolic and genetic diseases. Excess blood is spotted on Guthrie cards and archived by many states in biobanks for follow-up diagnoses and public health research. However, storage environment may vary across biobanks and across time within biobanks. With increased applications of DNA extracted from spots for genetic studies, identifying factors associated with genotyping success is critical to maximize DNA quality for future studies.

Method

We evaluated 399 blood spots, which were part of a genome-wide association study of childhood leukemia risk in children with Down syndrome, archived at the Michigan Neonatal Biobank between 1992 and 2008. High quality DNA was defined as having post-quality control call rate ≥ 99.0% based on the Illumina GenomeStudio 2.0 GenCall algorithm after processing the samples on the Illumina Infinium Global Screening Array. Bivariate analyses and multivariable logistic regression models were applied to evaluate effects of storage environment and storage duration on DNA genotyping quality.

Results

Both storage environment and duration were associated with sample genotyping call rates (p-values < 0.001). Sample call rates were associated with storage duration independent of storage environment (p-trend = 0.006 for DBS archived in an uncontrolled environment and p-trend = 0.002 in a controlled environment). However, 95% of the total sample had high genotyping quality with a call rate ≥ 95.0%, a standard threshold for acceptable sample quality in many genetic studies.

Conclusion

Blood spot DNA quality was lower in samples archived in uncontrolled storage environments and for samples archived for longer durations. Still, regardless of storage environment or duration, neonatal biobanks including the Michigan Neonatal Biobanks can provide access to large collections of spots with DNA quality acceptable for most genotyping studies.

Inherited genetic susceptibility to acute lymphoblastic leukemia in Down syndrome

Children with Down syndrome (DS) have a 20-fold increased risk of acute lymphoblastic leukemia (ALL) and distinct somatic features, including CRLF2 rearrangement in ∼50% of cases; however, the role of inherited genetic variation in DS-ALL susceptibility is unknown. We report the first genome-wide association study of DS-ALL, comprising a meta-analysis of 4 independent studies, with 542 DS-ALL cases and 1192 DS controls. We identified 4 susceptibility loci at genome-wide significance: rs58923657 near IKZF1 (odds ratio [OR], 2.02; Pmeta = 5.32 × 10-15), rs3731249 in CDKN2A (OR, 3.63; Pmeta = 3.91 × 10-10), rs7090445 in ARID5B (OR, 1.60; Pmeta = 8.44 × 10-9), and rs3781093 in GATA3 (OR, 1.73; Pmeta = 2.89 × 10-8). We performed DS-ALL vs non-DS ALL case-case analyses, comparing risk allele frequencies at these and other established susceptibility loci (BMI1, PIP4K2A, and CEBPE) and found significant association with DS status for CDKN2A (OR, 1.58; Pmeta = 4.1 × 10-4). This association was maintained in separate regression models, both adjusting for and stratifying on CRLF2 overexpression and other molecular subgroups, indicating an increased penetrance of CDKN2A risk alleles in children with DS. Finally, we investigated functional significance of the IKZF1 risk locus, and demonstrated mapping to a B-cell super-enhancer, and risk allele association with decreased enhancer activity and differential protein binding. IKZF1 knockdown resulted in significantly higher proliferation in DS than non-DS lymphoblastoid cell lines. Our findings demonstrate a higher penetrance of the CDKN2A risk locus in DS and serve as a basis for further biological insights into DS-ALL etiology.

Adaptive functioning in pediatric brain tumor survivors: An examination of ethnicity and socioeconomic status

BACKGROUND

Survivors of pediatric brain tumor are at risk for adaptive difficulties. The present study examined adaptive functioning in a multiethnic sample of survivors accounting for socioeconomic status, and whether demographic, diagnostic, and/or treatment-related variables predict adaptive outcomes.

METHOD

Participants included a multiethnic sample of survivors (58 Caucasian, 34 Hispanic, and 22 other non-Caucasian; M age = 14.05 years, SD = 4.33) who were approximately seven years post-treatment. Parents rated adaptive functioning and provided demographic information. Diagnostic and treatment-related information was abstracted from the electronic medical record.

RESULTS

Parent ratings of adaptive functioning were similar across Caucasian, Hispanic, and other non-Caucasian survivors covarying for family income and primary caregiver education, both of which served as proxies for socioeconomic status. All ethnic groups were rated lower than the normative mean in overall adaptive functioning as well as the specific domains of conceptual, social, and practical skills. Demographic, diagnostic, and treatment-related variables were differentially associated with adaptive functioning in survivors of pediatric brain tumor, though socioeconomic status emerged as a strong significant predictor of adaptive functioning domains.

CONCLUSIONS

Adaptive outcomes do not differ as a function of ethnicity after accounting for primary caregiver education and family income. Racial and ethnic minorities may be at increased risk for poorer outcomes given their overrepresentation at lower income levels. Assessing demographic and treatment-related variables early on may be helpful in identifying children likely to develop adaptive difficulties.

Association Between Birth Defects and Cancer Risk Among Children and Adolescents in a Population-Based Assessment of 10 Million Live Births

Importance

Birth defects affect approximately 1 in 33 children. Some birth defects are known to be strongly associated with childhood cancer (eg, trisomy 21 and acute leukemia). However, comprehensive evaluations of childhood cancer risk in those with birth defects have been limited in previous studies by insufficient sample sizes.

Objectives

To identify specific birth defect-childhood cancer (BD-CC) associations and characterize cancer risk in children by increasing number of nonchromosomal birth defects.

Design, Setting, and Participants

This multistate, population-based registry linkage study pooled statewide data on births, birth defects, and cancer from Texas, Arkansas, Michigan, and North Carolina on 10 181 074 children born from January 1, 1992, to December 31, 2013. Children were followed up to 18 years of age for a diagnosis of cancer. Data were retrieved between September 26, 2016, and September 21, 2017, and data analysis was performed from September 2, 2017, to March 21, 2019.

Exposures

Birth defects diagnoses (chromosomal anomalies and nonchromosomal birth defects) recorded by statewide, population-based birth defects registries.

Main Outcomes and Measures

Cancer diagnosis before age 18 years, as recorded in state cancer registries. Cox regression models were used to generate hazard ratios (HRs) and 95% CIs to evaluate BD-CC associations and the association between number of nonchromosomal defects and cancer risk.

Results

Compared with children without any birth defects, children with chromosomal anomalies were 11.6 (95% CI, 10.4-12.9) times more likely to be diagnosed with cancer, whereas children with nonchromosomal birth defects were 2.5 (95% CI, 2.4-2.6) times more likely to be diagnosed with cancer before 18 years of age. An increasing number of nonchromosomal birth defects was associated with a corresponding increase in the risk of cancer. Children with 4 or more major birth defects were 5.9 (95% CI, 5.3-6.4) times more likely to be diagnosed with cancer compared with those without a birth defect. In the analysis of 72 specific BD-CC patterns, 40 HRs were statistically significant (adjusted P < .05) after accounting for multiple comparisons. Cancers most frequently associated with nonchromosomal defects were hepatoblastoma and neuroblastoma.

Conclusions and Relevance

Several significant and novel associations were observed between specific birth defects and cancers. Among children with nonchromosomal birth defects, the number of major birth defects diagnosed was significantly and directly associated with cancer risk. These findings could inform clinical treatment for children with birth defects and may elucidate mechanisms that lead to these complex outcomes.

Abstract 1575: DNA methylation-derived neutrophil-to-lymphocyte ratio and survival among pediatric medulloblastoma patients

Background/Objectives: Medulloblastoma is the most common malignant brain tumor diagnosed in children. Current risk-stratification methods of pediatric medulloblastoma do not fully explain the observed variability in clinical outcomes. Methylation-derived neutrophil-to-lymphocyte ratio (mdNLR) captures immune-specific information and has been identified as a potential prognostic biomarker of outcomes in various cancers, including adult brain tumors. Therefore, we evaluated the association between blood-derived mdNLR and overall survival in a cohort of patients with pediatric medulloblastoma.

Design/Methods: We identified pediatric patients diagnosed and treated for medulloblastoma at Texas Children’s Cancer Center between 1995 and 2015. Peripheral blood DNA methylation was measured using the Infinium Human Methylation 450K Beadchip. Methylation data underwent quality control, including beta-mixture quantile normalization and batch correction. Immune cell proportions (CD4+ T-Cells, CD8+ T-Cells, B-cells, natural killer cells, monocytes, and granulocytes) were estimated using cellular deconvolution methods and used to estimate mdNLR, which was then log-transformed to improve normality. Cox regression models were estimated to evaluate the association between mdNLR and overall survival.

Results: Of the 78 eligible patients include in this analysis, 83% (n=65) were alive at last follow-up (median follow-up=7.8 years). Deceased patients (n=13; median follow-up=2.6 years) had a higher mean mdNLR than patients who were alive at last contact (12.3 vs. 4.0, P = 0.046). Elevated log-transformed mdNLR was associated with an increased risk of death in both unadjusted models (HR=1.68, 95%CI: 1.11-2.55) and models accounting for age, sex, race, and clinical risk group (HR=1.97, 95%CI: 1.12-3.45).

Conclusion: We identified a significant association between peripheral blood mdNLR and survival in pediatric medulloblastoma. As a promising prognostic biomarker of outcomes, mdNLR captures immune-specific information and is a potential avenue of research in settings where cytologic determination of NLR may not be possible. Future work should investigate the relationship between elevated mdNLR and specific pediatric medulloblastoma molecular subtypes.

Citation Format: Vidal M. Arroyo, Philip J. Lupo, Michael E. Scheurer, Surya P. Rednam, Jeffrey C. Murray, M F. Okcu, Murali M. Chintagumpala, Austin L. Brown. DNA methylation-derived neutrophil-to-lymphocyte ratio and survival among pediatric medulloblastoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1575.

Abstract 3287: Survival disparities for second primary malignancies diagnosed among childhood cancer survivors: A population-based assessment

Background: Curative therapy places childhood cancer survivors at increased risk of second primary malignancies (SPMs). However, there have been few population-based attempts to characterize differences in outcomes between SPMs in childhood cancer survivors and comparable de novo first primary malignancies (FPMs).

Methods: We extracted clinical and demographic information from childhood cancer survivors who developed SPMs and from individuals with comparable de novo FPMs using the Surveillance, Epidemiology, and End Results (SEER) 1973-2015 database. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated with Cox proportional hazards models comparing overall survival (OS) between individuals with and without a history of childhood cancer. OS was evaluated overall and within specific cancers diagnosed in ≥50 childhood cancer survivors. Models accounted for potential confounders, including sex, race, age, decade of diagnosis, histology, and disease stage.

Results: Compared to individuals with FPMs (n=1,332,203), childhood cancer survivor with a similar SPM as the FPMs (n=1,409) experienced poorer OS (HR=1.86, 95%CI: 1.72-2.02) after accounting for age, sex, race, and decade of diagnosis. Estimated five-year overall survival for SPMs diagnosed in survivors of childhood cancer was 61.7% (95% CI: 58.9-64.4), compared to 77.4% (95% CI: 75.0-79.5) among de novo FPMs propensity score-matched on confounding factors. A history of childhood cancer remained a poor prognostic factor for all specific cancer evaluated, including: breast (HR=2.07, 95%CI: 1.63-2.62), thyroid (HR=3.59, 95%CI: 2.08-6.19), acute myeloid leukemia (HR=2.38, 95%CI:1.87-3.05), brain (HR=2.09, 95%CI:1.72-2.55), melanoma (HR=2.57, 95%CI: 1.55-4.27), bone (HR=1.88, 95%CI:1.37-2.57), and soft tissue sarcoma (HR=2.44, 95%CI: 1.78-3.33). Survival disparities were most pronounced in survivors diagnosed with a childhood cancer before age 10 (HR=2.83, 95%CI: 2.46-3.25), diagnosed with a SPM within 10 years of the childhood cancer (HR=2.61, 95%CI: 2.29-2.99), and exposed to radiotherapy during childhood (HR=2.13, 95%CI: 1.92-2.37).

Conclusion: Compared to individuals without a prior cancer diagnosis, survivors of childhood cancer with a SPM experience inferior outcomes. These survival disparities persist across cancer types, therapeutic exposures, and clinical factors.

Citation Format: Austin L. Brown, Vidal M. Arroyo, Jennifer Agrusa, Michael E. Scheurer, Maria M. Gramatges, Philip J. Lupo. Survival disparities for second primary malignancies diagnosed among childhood cancer survivors: A population-based assessment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3287.

Survival disparities for second primary malignancies diagnosed among childhood cancer survivors: A population-based assessment

BACKGROUND

Curative therapy places childhood cancer survivors at increased risk for second primary malignancies (SPMs). However, there have been few population-based attempts to characterize differences between outcomes of SPMs in childhood cancer survivors and outcomes of first primary malignancies (FPMs).

METHODS

Clinical and demographic information about childhood cancer survivors who developed SPMs and individuals with comparable FPMs was extracted from the Surveillance, Epidemiology, and End Results program. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated with Cox proportional hazards models comparing the overall survival (OS) of individuals with and without a history of childhood cancer. OS was evaluated both overall and for specific cancers diagnosed in 50 or more childhood cancer survivors. Models accounted for potential confounders, including sex, race, age, treatment decade, histology, and disease stage.

RESULTS

Compared with individuals with FPMs (n = 1,332,203), childhood cancer survivors (n = 1409) with an SPM experienced poorer OS (HR, 1.86; 95% CI, 1.72-2.02) after the study had accounted for cancer type, age, sex, race, and decade of diagnosis. A history of childhood cancer remained a poor prognostic factor for all specific cancers evaluated, including breast cancer (HR, 2.07; 95% CI, 1.63-2.62), thyroid cancer (HR, 3.59; 95% CI, 2.08-6.19), acute myeloid leukemia (HR, 2.38; 95% CI, 1.87-3.05), brain cancer (HR, 2.09; 95% CI, 1.72-2.55), melanoma (HR, 2.57; 95% CI, 1.55-4.27), bone cancer (HR, 1.88; 95% CI, 1.37-2.57), and soft-tissue sarcoma (HR, 2.44; 95% CI, 1.78-3.33).

CONCLUSIONS

Compared with individuals without a prior cancer diagnosis, survivors of childhood cancer with an SPM experienced inferior outcomes. Survival disparities were observed for the most frequent SPMs diagnosed in childhood cancer survivors.

Weight trends in a multiethnic cohort of pediatric acute lymphoblastic leukemia survivors: A longitudinal analysis

BACKGROUND

As survival rates for childhood acute lymphoblastic leukemia (ALL) continue to improve, there is growing concern over the chronic health conditions that survivors face. Given that survivors of childhood ALL are at increased risk of cardiovascular complications and obesity, we sought to characterize BMI trends from diagnosis through early survivorship in a multi-ethnic, contemporary cohort of childhood ALL patients and determine if early weight change was predictive of long-term weight status.

METHODS

The study population consisted of ALL patients aged 2-15 years at diagnosis who were treated with chemotherapy alone at Texas Children's Hospital. Each patient had BMI z-scores collected at diagnosis, 30-days post-diagnosis, and annually for five years. Linear regression models were estimated to evaluate the association between: 1) BMI z-score change in the first 30 days and BMI z-scores at five-years post-diagnosis; and 2) BMI z-score change in the first year post-diagnosis and BMI z-scores at five-years post-diagnosis.

RESULTS

This retrospective cohort study included longitudinal data from 121 eligible patients. The mean BMI z-scores for the population increased significantly (p-value<0.001) from baseline (mean = 0.25) to 30 days post-diagnosis (mean = 1.17) before plateauing after one year post-diagnosis (mean = 0.99). Baseline BMI z-scores were statistically significant predictors to five year BMI z-scores (p <0.001). Independent of baseline BMI z-score and other clinical factors, the BMI z-score at one year post-diagnosis was significantly associated with BMI z-score at five-years post-diagnosis (β = 0.63, p <0.001), while BMI z-score at 30 days post-diagnosis was not (β = 0.10, p = 0.23).

CONCLUSION

Our results suggest that weight gain within the first year after diagnosis is more strongly associated with long-term BMI than early weight gain (within 30 days). If confirmed, this information may help identify a window of time during therapy when ALL patients would benefit most from weight management directed interventions.

The role of genetic variation in DGKK on moderate and severe hypospadias

BACKGROUND

Recent genome-wide association studies of hypospadias have implicated the role of genetic variants in or near the diacylglycerol kinase kappa (DGKK) gene. However, these variants are largely identified among samples of mild and moderate hypospadias cases. Therefore, we evaluated previously identified DGKK variants among second- and third-degree hypospadias cases and controls recruited in Arkansas, a state characterized by a high birth prevalence of hypospadias.

METHODS

Second- and third-degree hypospadias non-Hispanic white cases (n = 36 and n = 9, respectively) and controls (n = 45) were recruited at Arkansas Children's Hospital. Preputial tissue was collected on cases and controls between 2013 and 2017. Cases and controls were genotyped using the Illumina Infinium Global Screening Array. We used logistic regression models to assess the association of genotyped and imputed genetic variants mapped to the DGKK region with second- and third-degree hypospadias.

RESULTS

All families self-reported as non-Hispanic white and genetic principal component analyses did not demonstrate evidence of population stratification. Five DGKK variants previously reported as associated with hypospadias were identified in the genotype data. None of the variants were associated with second- or third-degree hypospadias (range of odds ratios = 0.7-0.9, all p > .05).

CONCLUSIONS

In our analyses, genetic variation in DGKK does not play a role in the development of moderate and severe hypospadias. Our findings provide support to the etiologic heterogeneity of hypospadias by all classifications of severity.

Pilot study of DNA methylation-derived neutrophil-to-lymphocyte ratio and survival in pediatric medulloblastoma

INTRODUCTION

Methylation-derived neutrophil-to-lymphocyte ratio (mdNLR) has been identified as a potential prognostic biomarker of outcomes in various cancers. We evaluated the prognostic value of blood-derived mdNLR within a retrospective cohort of pediatric medulloblastoma patients.

MATERIALS AND METHODS

DNA methylation was measured in archival peripheral blood samples collected on 56 pediatric medulloblastoma patients. Hazard ratios (HR) and 95% confidence intervals (CI) for the association between mdNLR and survival were evaluated using Cox proportional hazard models.

RESULTS

Compared to patients who were alive at last follow-up (n = 43), the mean mdNLR value was slightly higher in deceased patients (n = 13) (12.3 vs. 5.2,P =  0.163). Elevated log-transformed mdNLR was suggestively associated with an increased likelihood of death in unadjusted models (HR=1.43, 95%CI: 0.92-2.22) and significantly associated with mortality in adjusted models (HR=1.61, 95%CI: 1.01-2.58).

DISCUSSION

Future work is warranted to investigate the relationship between mdNLR outcomes in specific pediatric medulloblastoma molecular subgroups.

DNA methylation and obesity in survivors of pediatric acute lymphoblastic leukemia: A report from the Childhood Cancer Survivor Study

Because survivors of pediatric acute lymphoblastic leukemia (ALL) are more likely to be obese than unaffected contemporaries, we compared DNA methylation profiles between normal-weight and obese survivors at adiposity-associated CpG sites previously-reported by epigenome-wide association studies (EWAS) of body mass index (BMI) in the general population. We selected 96 ALL survivors from the Childhood Cancer Survivor Study: 48 obese and 48 normal weight. The Illumina HumanMethylation450 BeadChip was used to compare DNA methylation at 211 loci identified in EWAS of BMI in the general population. Thirty-nine loci were associated (false discovery rate <0.05) with obesity among survivors who only received chemotherapy (n = 49). No loci were significantly associated with obesity among CRT-exposed survivors (n = 47). Our results suggest that previously identified BMI-DNA methylation loci are associated with obesity in ALL survivors who were spared CRT, while no loci were significantly associated with obesity in survivors who received CRT.

A Review on Energy, Environmental, and Sustainability Implications of Connected and Automated Vehicles

Connected and automated vehicles (CAVs) are poised to reshape transportation and mobility by replacing humans as the driver and service provider. While the primary stated motivation for vehicle automation is to improve safety and convenience of road mobility, this transformation also provides a valuable opportunity to improve vehicle energy efficiency and reduce emissions in the transportation sector. Progress in vehicle efficiency and functionality, however, does not necessarily translate to net positive environmental outcomes. Here, we examine the interactions between CAV technology and the environment at four levels of increasing complexity: vehicle, transportation system, urban system, and society. We find that environmental impacts come from CAV-facilitated transformations at all four levels, rather than from CAV technology directly. We anticipate net positive environmental impacts at the vehicle, transportation system, and urban system levels, but expect greater vehicle utilization and shifts in travel patterns at the society level to offset some of these benefits. Focusing on the vehicle-level improvements associated with CAV technology is likely to yield excessively optimistic estimates of environmental benefits. Future research and policy efforts should strive to clarify the extent and possible synergetic effects from a systems level to envisage and address concerns regarding the short- and long-term sustainable adoption of CAV technology.

Disparities in Neurotoxicity Risk and Outcomes among Pediatric Acute Lymphoblastic Leukemia Patients

Purpose: Methotrexate chemotherapy can be associated with neurologic complications during therapy and long-term neurologic deficits. This study evaluated demographic and clinical factors associated with incidence of methotrexate neurotoxicity and described the impact of neurotoxicity on acute lymphoblastic leukemia (ALL) therapy in pediatric patients.Experimental Design: Patients were enrolled between 2012 and 2017 from three pediatric cancer treatment centers in the United States. Medical records for suspected cases of methotrexate neurotoxicity, defined as an acute neurologic event following methotrexate therapy, were reviewed. Cox proportional hazards models were used to estimate the association between race/ethnicity and methotrexate neurotoxicity. Multivariable linear regression models compared treatment outcomes between patients with and without methotrexate neurotoxicity.Results: Of the 280 newly diagnosed patients enrolled, 39 patients (13.9%) experienced methotrexate neurotoxicity. Compared with non-Hispanic whites, Hispanic patients experienced the greatest risk of methotrexate neurotoxicity (adjusted HR, 2.43; 95% CI, 1.06-5.58) after accounting for sex, age at diagnosis, BMI Z-score at diagnosis, and ALL risk stratification. Patients who experienced a neurotoxic event received an average of 2.25 fewer doses of intrathecal methotrexate. Six of the 39 cases of neurotoxicity (15.4%) experienced relapse during the study period, compared with 13 of the 241 (2.1%) patients without neurotoxicity (P = 0.0038).Conclusions: Hispanic ethnicity was associated with increased risk of methotrexate neurotoxicity, which was associated with treatment modifications and relapse. Understanding the mechanism and predictors of methotrexate neurotoxicity is important to improving treatment outcomes in pediatric ALL. Clin Cancer Res; 24(20); 5012-7. ©2018 AACR.

Abstract LB-161: A population-based assessment of cancer risk among children with non-chromosomal birth defects in 10 million live births

Purpose: While cancer risk is increased among children with chromosomal birth defects, less is known about associations between specific non-chromosomal structural birth defects and specific childhood cancers. To investigate these, we established a population-based retrospective cohort of &gt;10 million children by pooling statewide registry data from four U.S. states (Texas, Michigan, North Carolina, and Arkansas) for the period 1992-2013.

Methods: Individual level data from birth certificates, birth defects registries, and cancer registries were linked in each state; demographic and diagnostic variables were harmonized; and the data were pooled for the overall analysis. We used Cox proportional hazards models to evaluate associations between 60 birth defects and 31 childhood cancers when there were five or more comorbid cases. A hazard ratio (HR) and 95% confidence interval (CI) was calculated for each birth defect-childhood cancer (BD-CC) pairwise combination, adjusted for maternal age, infant sex, and state. The false discovery rate (FDR) was computed via the Benjamini-Hochberg procedure to account for multiple comparisons.

Results: We identified 517,548 children with non-chromosomal structural birth defects and 14,774 children with cancer. The risk of any cancer was increased among children with any non-chromosomal structural defect compared to children without any birth defect (HR=2.6, 95% CI 2.4-2.7). Of 2,511 potential BD-CC combinations, we tested 606 where there were ≥5 comorbid cases and identified 496 BD-CC associations with significantly elevated HRs at a 5% FDR. No significant inverse associations were identified for any BD-CC combination. Notably, hepatoblastoma, astrocytoma, ependymoma, and extracranial germ cell tumors were each strongly associated with several birth defects. For example, the risk of hepatoblastoma was increased among children with atrial septal defects (HR=12.5, 95% CI 7.9-19.7) and craniosynostosis (HR=15.4, 95% CI 7.6-31.3). Astrocytoma and ependymoma were associated with central nervous system (CNS) defects (HR=6.7, 95% CI 4.6-9.8 and HR=7.4, 95%CI 3.5-15.7, respectively). Elevated risk of extracranial germ cell tumors was observed among children with CNS defects (HR=22.5, 95% CI 10.9-46.4) and obstructive genitourinary defects (HR=32.4, 95% CI 16.2-64.6).

Conclusions: By pooling registry data across four U.S. states, we were able to evaluate specific BD-CC patterns and report several novel associations. Our findings suggest that children with non-chromosomal birth defects have a significantly elevated risk of several childhood cancers. These findings may inform research into the etiologies of childhood cancer, as well as new cancer surveillance protocols for children with non-chromosomal birth defects. This work was supported by the Cancer Prevention Research Institute of Texas.

Citation Format: Jeremy M. Schraw, Tania A. Desrosiers, Wendy N. Nembhard, Glenn Copeland, Robert E. Meyer, Austin L. Brown, Tiffany M. Chambers, Heather E. Danysh, Saumya Sisoudiya, Chunqiao Luo, Amir Mian, Michael E. Scheurer, Sharon E. Plon, Philip J. Lupo. A population-based assessment of cancer risk among children with non-chromosomal birth defects in 10 million live births [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-161.

Abstract 2967: Ethnic-specific risk of neurotoxocity and its impact on treatment outcomes among pediatric patients receiving acute lymphoblastic leukemia therapy

Purpose: Because of the increasing awareness that Hispanics diagnosed with acute lymphoblastic leukemia (ALL) often experience worse outcomes, we sought to evaluate the risk of methotrexate (MTX)-related neurotoxicity (NT) by ethnic group and evaluate its effects on treatment outcomes in a multi-institutional prospective cohort of pediatric patients (2-17 years old).

Methods: Patients with ALL were prospectively recruited from 3 pediatric cancer centers in the United States for the period 2012-2017 and systematically followed for the development of treatment-related symptoms and toxicities. For this analysis, suspected NT cases were defined as patients with a neurologic event following intrathecal (IT) and/or intravenous (IV) MTX that led to a change in subsequent MTX therapy. Cumulative incidence of MTX NT was calculated by ethnic group. Multivariable linear regression models were generated to compare treatment differences between patients with and without MTX NT. The frequency of all-cause and central nervous system (CNS) relapse was compared between patients with and without MTX NT using the log-rank test and Cox regression models.

Results: Of the 280 patients enrolled, 39 (13.9%) experienced MTX NT (median follow-up = 22.6 months; range: 1.3 - 55.6 months). Cumulative incidence of MTX NT was 21.8% among Hispanic patients compared to 7.0% among non-Hispanic patients (p &lt;0.001). After adjusting for relevant clinical characteristics, Hispanic patients were 2.74 times more likely to develop MTX NT compared to non-Hispanic white patients (95% CI: 1.21-6.19). Patients who experienced MTX NT received an average of 2.25 fewer doses of IT MTX (95% CI: 1.73-2.77), independent of treatment risk group, sex, or age. Six cases of MTX NT (15.4%) experienced all-cause relapse during the study period, compared to 13 (2.1%) patients without MTX NT (log-rank p = 0.0038). Similarly, CNS relapse was more frequent among patients with MTX NT (10.3%) than patients without NT (2.1%; log-rank p = 0.0014). In univariate Cox regression models, MTX NT was significantly associated with CNS relapse (HR: 3.80, 95% CI: 1.44-10.02), a trend which remained after individually accounting for treatment risk arm (HR: 2.92, 95% CI: 1.07-7.95), MRD status at day 29 (HR: 3.49, 95% CI: 1.32-9.24), race and ethnicity (HR: 3.15, 95% CI: 1.13-8.79), age at diagnosis (HR: 2.56, 95% CI: 0.91-7.21), and sex (HR: 3.82, 95% CI: 1.44-10.10).

Conclusion: We identified an increased risk of relapse, specifically in the CNS, among ALL patients following MTX NT, which was not fully explained by other clinical risk factors. Further, incidence of NT was higher among Hispanic patients in our clincs. This is particularly interesting given that Hispanic patients typically present with more favorable disease characterstics, yet often experience worse treatment outcomes.

Citation Format: Michael E. Scheurer, Olga A. Taylor, Austin L. Brown, Julienne Brackett, ZoAnne E. Dreyer, Ida (Ki) Moore, Pauline Mitby, Mary C. Hooke, Philip J. Lupo, Marilyn J. Hockenberry. Ethnic-specific risk of neurotoxocity and its impact on treatment outcomes among pediatric patients receiving acute lymphoblastic leukemia therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2967.

Abstract 222: Genome-wide association study of acute lymphoblastic leukemia in children with Down syndrome

Purpose: Children with Down syndrome (DS) have a 20-fold increased risk of acute lymphoblastic leukemia (ALL) compared to children without DS. While genome-wide association studies (GWAS) have identified several susceptibility loci in childhood ALL, studies of ALL in children with DS are lacking. Therefore, we conducted the first GWAS of DS-ALL.

Methods: We analyzed independent cohorts of: 1) 226 newly diagnosed DS-ALL cases from Children's Oncology Group (COG) ALL trials (2000-2013) and 436 DS controls from the National Down Syndrome Project (NDSP), 2) 124 additional COG ALL cases (2011-2015) and 336 additional NDSP DS controls, 3) 20 DS-ALL cases and 275 DS controls from Michigan neonatal bloodspots, and 4) 157 DS-ALL cases and 145 DS controls largely from neonatal bloodspots from California and Washington. Genotyping was performed with Affymetrix or Illumina single nucleotide polymorphism (SNP) arrays. STRUCTURE software was used to define European (372 cases, 1,056 controls), Hispanic (140 cases, 136 controls), and African (15 cases, 62 controls) genetic ancestry. After genome-wide imputation and quality control, ancestry- and cohort-specific associations were evaluated at &gt;6,000,000 autosomal SNPs with minor allele frequency ≥1%. Associations were meta-analyzed across cohort and ancestry groups, assuming additive allelic effects.

Results: Genome-wide significant (p&lt;5x10-8) association signals were identified for known ALL susceptibility loci, including rs58923657 near IKZF1 (Odds Ratio [OR]=2.02, p=5.32x10-15), CDKN2A missense mutation rs3731249 (OR=3.63, p=3.91x10-10), rs3781093 near GATA3 (OR=1.73, p=2.89x10-8), and rs7090445 near ARID5B (OR=1.57, p=2.93x10-8). A novel potential risk locus was identified at chromosome 20q11.21 (rs78019519, OR=3.17, p=5.11x10-7) with consistent effects observed across each cohort and ancestry group. This SNP is in the promoter region of the oncogene TPX2 and is also associated with expression of HM13 in whole blood in the Genotype-Tissue Expression (GTEx) Portal.

Conclusion: We confirmed that known ALL susceptibility loci in children without DS, including IKZF1, CDKN2A, GATA3, PIP4K2A and ARID5B, also confer risk of ALL in children with DS, with CDKN2A showing the largest effect size. We also identified a potentially novel locus associated with ALL susceptibility in DS at chromosome 20q11.21. Additional investigation of these loci is ongoing and may advance our understanding of DS-ALL etiology and biology.

Citation Format: Austin L. Brown, Adam J. de Smith, Michael E. Scheurer, Noah A. Kallsen, Shanna A. Peyton, Gareth E. Davies, Erik A. Ehli, Michael E. Zwick, Naomi Winick, Kelly Maloney, Anne L. Angiolillo, Reuven Schore, MIchael M. Burke, Wanda L. Salzer, Nyla A. Heerema, Andrew J. Carroll, Michael J. Borowitz, Brent L. Wood, William L. Carroll, Elizabeth A. Raetz, Elanor Feingold, Stephanie L. Sherman, Wenjian Yang, Meenakshi Devidas, Kyle Walsh, Andrew T. DeWan, Maria S. Pombo-de-Oliveira, Jeffrey W. Taub, Daniel Sinnett, Jasmine Healy, Jillian M. Birch, Lisa F. Barcellos, Helen Hansen, Ivan Smirnov, Charles G. Mullighan, Stephen P. Hunger, Ching-Hon Pui, Mignon Loh, Joe L. Wiemels, Xiaomei Ma, Catherine Metayer, Beth A. Mueller, Mary V. Relling, Jun J. Yang, Philip J. Lupo, Karen R. Rabin. Genome-wide association study of acute lymphoblastic leukemia in children with Down syndrome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 222.

DNA methylation of a novel PAK4 locus influences ototoxicity susceptibility following cisplatin and radiation therapy for pediatric embryonal tumors

Background

Ototoxicity is a common adverse side effect of platinum chemotherapy and cranial radiation therapy; however, individual susceptibility is highly variable. Therefore, our objective was to conduct an epigenome-wide association study to identify differentially methylated cytosine-phosphate-guanine (CpG) sites associated with ototoxicity susceptibility among cisplatin-treated pediatric patients with embryonal tumors.

Methods

Samples were collected for a discovery cohort (n = 62) and a replication cohort (n = 18) of medulloblastoma and primitive neuroectodermal tumor patients. Posttreatment audiograms were evaluated using the International Society of Paediatric Oncology (SIOP) Boston Ototoxicity Scale. Genome-wide associations between CpG methylation and ototoxicity were examined using multiple linear regression, controlling for demographic and treatment factors.

Results

The mean cumulative dose of cisplatin was 330 mg/m2 and the mean time from end of therapy to the last available audiogram was 6.9 years. In the discovery analysis of 435233 CpG sites, 6 sites were associated with ototoxicity grade (P < 5 × 10-5) after adjusting for confounders. Differential methylation at the top CpG site identified in the discovery cohort (cg14010619, PAK4 gene) was replicated (P = 0.029) and reached genome-wide significance (P = 2.73 × 10-8) in a combined analysis. These findings were robust to a sensitivity analysis evaluating other potential confounders.

Conclusions

We identified and replicated a novel CpG methylation loci (cg14010619) associated with ototoxicity severity. Methylation at cg14010619 may modify PAK4 activity, which has been implicated in cisplatin resistance in malignant cell lines.

Aerobic method for the synthesis of nearly size-monodisperse bismuth nanoparticles from a redox non-innocent precursor

Herein, we report an aerobic synthesis method to produce bismuth nanoparticles (Bi NPs) with average diameters in the range 40-80 nm using commercially available bismuth triiodide (BiI₃) as the starting material; the method uses only readily available chemicals and conventional laboratory equipment. Furthermore, size data from replicates of the synthesis under standard reaction conditions indicate that this method is highly reproducible in achieving Bi NP populations with low standard deviations in the mean diameters. We also investigated the mechanism of the reaction, which we determined results from the reduction of a soluble alkylammonium iodobismuthate precursor species formed in situ. Under appropriate concentration conditions of iodobismuthate anion, we demonstrate that burst nucleation of Bi NPs results from reduction of Bi³⁺ by the coordinated, redox non-innocent iodide ligands when a threshold temperature is exceeded. Finally, we demonstrate phase transfer and silica coating of the Bi NPs, which results in stable aqueous colloids with retention of size, morphology, and colloidal stability. The resultant, high atomic number, hydrophilic Bi NPs prepared using this synthesis method have potential for application in emerging x-ray contrast and x-ray therapeutic applications.

Genome-wide discovery of novel susceptibility loci for treatment-associated hypothyroidism among survivors of pediatric medulloblastoma

10571

Background: Pediatric medulloblastoma patients exposed to craniospinal radiation (CSI) are at high risk of developing endocrinopathies, including hypothyroidism. We sought to evaluate the role of genetic variation on hypothyroidism susceptibility among survivors of pediatric medullobastoma. Methods: Records from 61 medulloblastoma survivors treated at Texas Children’s Hospital between 1997 and 2013 were reviewed. All patients completed baseline and yearly follow-up thyroid assessments. Genome-wide genotyping was performed on Illumina HumanOmni1 and HumanOmni2.5 BeadChip single nucleotide polymorphism (SNP) arrays. Following standard quality control measures and exclusion of rare variants (minor allele frequency [MAF] < 5%), 572,562 autosomal SNPs were included in our analyses. The association between each SNP and hypothyroidism was tested using Fisher’s exact test and logistic regression, assuming additive allelic effects. Results: A total of 25 patients (41%) developed hypothyroidism with median follow-up of 8.3 years from diagnosis (range: 1.8-17.2 years). Primary hypothyroidism was identified in 9 (36%) cases, while the remaining 16 (64%) developed central hypothyroidism. Hypothyroidism was detected in 13 of 40 (33%) individuals exposed to < 30 Gy CSI and 12 of 21 (57%) individuals exposed to ≥30 Gy CSI (p = 0.06). Genome-wide association analysis identified several risk loci, including 3 variants associated with hypothyroidism (p-value < 1x10-5) at chromosome 2q11.2 ( NPAS2 gene). The top overall SNP (MAF = 27.5%, p-value = 6.5x10-7) remained strongly associated with hypothyroidism after accounting for possible confounders, including CSI dose, CSI type (proton/photon), age, sex, and genetic ancestry. Conclusions: Our findings suggest susceptibility to treatment-related hypothyroidism is strongly influenced by common genetic variation in NPAS2. The NPAS2 gene, a central component of the circadian rhythm network, is a transcriptional activator and regulator of DNA damage response and DNA repair genes.

Evaluation of maternal and perinatal characteristics on childhood lymphoma risk: A population-based case-control study

BACKGROUND

Lymphoma is one of the most common pediatric malignancies; however, there are few well-established risk factors. Therefore, we investigated if maternal and perinatal characteristics influenced the risk of childhood lymphoma.

PROCEDURE

Information on cases (n = 374) diagnosed with lymphoma and born in Texas for the period 1995-2011 was obtained from the Texas Cancer Registry. Birth certificate controls were randomly selected at a ratio of 10 controls per 1 case for the same period of 1995-2011. Unconditional logistic regression was used to generate unadjusted (OR) and adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the following histologic subtypes: Hodgkin (HL), Burkitt (BL), and non-BL non-HLs (non-BL NHLs).

RESULTS

Overall, our findings indicate specific maternal and perinatal characteristics influence childhood lymphoma risk. Mexico-born mothers were more likely to have offspring who developed BL compared to mothers born in the United States (U.S.; aOR: 2.15; 95% CI: 1.06-4.36). Further, mothers who resided at time of delivery in a county on the U.S.-Mexico border were more likely to give birth to offspring who developed non-BL NHL (aOR: 1.72; 95% CI: 1.11-2.67) compared to mothers not living on the U.S.-Mexico border at time of infant birth. Last, infants born large-for-gestational-age experienced a twofold increase in BL risk (aOR: 2.00; 95% CI: 1.10-3.65).

CONCLUSIONS

In this population-based assessment, we confirmed previously reported risk predictors of childhood lymphoma, including sex of infant, while highlighting novel risk factors that warrant assessment in future studies.