Trans-Ancestral Genetic Risk Factors for Treatment-Related Type 2 Diabetes Mellitus in Survivors of Childhood Cancer

PURPOSE

Type 2 diabetes mellitus (T2D) is a prevalent long-term complication of treatment in survivors of childhood cancer, with marked racial/ethnic differences in burden. In this study, we investigated trans-ancestral genetic risks for treatment-related T2D.

PATIENTS AND METHODS

Leveraging whole-genome sequencing data from the St Jude Lifetime Cohort (N = 3,676, 304 clinically ascertained cases), we conducted ancestry-specific genome-wide association studies among survivors of African and European genetic ancestry (AFR and EUR, respectively) followed by trans-ancestry meta-analysis. Trans-/within-ancestry replication including data from the Childhood Cancer Survivor Study (N = 5,965) was required for prioritization. Three external general population T2D polygenic risk scores (PRSs) were assessed, including multiancestry PRSs. Treatment risk effect modification was evaluated for prioritized loci.

RESULTS

Four novel T2D risk loci showing trans-/within-ancestry replication evidence were identified, with three loci achieving genome-wide significance (P < 5 × 10-8). Among these, common variants at 5p15.2 (LINC02112), 2p25.3 (MYT1L), and 19p12 (ZNF492) showed evidence of modifying alkylating agent-related T2D risk in both ancestral groups, but showed disproportionately greater risk in AFR survivors (AFR odds ratios [ORs], 3.95-17.81; EUR ORs, 2.37-3.32). In survivor-specific RNA-sequencing data (N = 207), the 19p12 locus variant was associated with greater ZNF492 expression dysregulation after exposures to alkylators. Elevated T2D risks across ancestry groups were only observed with increasing values for multiancestry T2D PRSs and were especially increased among survivors treated with alkylators (top v bottom quintiles: ORAFR, 20.18; P = .023; OREUR, 13.44; P = 1.3 × 10-9).

CONCLUSION

Our findings suggest therapy-related genetic risks contribute to the increased T2D burden among non-Hispanic Black childhood cancer survivors. Additional study of how therapy-related genetic susceptibility contributes to this disparity is needed.

Household income and health-related quality of life in children receiving treatment for acute myeloid leukemia: Potential impact of selection bias in health equity research

OBJECTIVE

Examine the influence of household income on health-related quality of life (HRQOL) among children with newly diagnosed acute myeloid leukemia (AML).

DESIGN

Secondary analysis of data prospectively collected from pediatric patients receiving treatment for AML at 14 hospitals across the United States.

EXPOSURE

Household income was self-reported on a demographic survey. The examined mediators included the acuity of presentation and treatment toxicity.

OUTCOME

Caregiver proxy reported assessment of patient HRQOL from the Peds QL 4.0 survey.

RESULT

Children with AML (n = 131) and caregivers were prospectively enrolled to complete PedsQL assessments. HRQOL scores were better for patients in the lowest versus highest income category (mean ± SD: 76.0 ± 14 household income <$25,000 vs. 59.9 ± 17 income ≥$75,000; adjusted mean difference: 11.2, 95% CI: 2.2-20.2). Seven percent of enrolled patients presented with high acuity (ICU-level care in the first 72 h), and 16% had high toxicity (any ICU-level care); there were no identifiable differences by income, refuting mediating roles in the association between income and HRQOL. Enrolled patients were less likely to be Black/African American (9.9% vs. 22.2%), more likely to be privately insured (50.4% vs. 40.7%), and more likely to have been treated on a clinical trial (26.7% vs. 18.5%) compared to eligible unenrolled patients not enrolled. Evaluations of potential selection bias on the association between income and HRQOL suggested differences in HRQOL may be smaller than observed or even in the opposing direction.

CONCLUSIONS

While primary analyses suggested lower household income was associated with superior HRQOL, differential participation may have biased these results. Future studies should partner with patients/families to identify strategies for equitable participation in clinical research.

Racial and ethnic disparities in acuity of presentation among children with newly diagnosed acute leukemia

We evaluated disparities in disease burden, organ dysfunction, vital signs, and timing of therapy in children newly presenting with acute leukemia. Among 899 patients with acute leukemia diagnosed at two large children's hospitals, a priori lab-based definitions of high disease burden, infection risk, renal dysfunction, and coagulopathy were applied to electronic health record data. Black patients with acute myeloid leukemia had increased prevalence of elevated white blood cell count and uric acid; Black patients with acute lymphoblastic leukemia demonstrated increased prevalence of coagulopathy. Black patients' presentation more frequently included multiple lab abnormalities consistent with advanced physiologic dysfunction. No differences were found in days to therapy initiation.

Trans-ancestral genetic study of diabetes mellitus risk in survivors of childhood cancer: a report from the St. Jude Lifetime Cohort and the Childhood Cancer Survivor Study

Type 2 diabetes mellitus (T2D) is an established late effect of treatment for childhood cancer. Leveraging detailed cancer treatment and whole-genome sequencing data among survivors of childhood cancer of European (EUR) and African (AFR) genetic ancestry in the St. Jude Lifetime Cohort (N=3,676; 304 cases), five novel diabetes mellitus (DM) risk loci were identified with independent trans-/within-ancestry replication, including in 5,965 survivors of the Childhood Cancer Survivor Study. Among these, common risk variants at 5p15.2 ( LINC02112 ), 2p25.3 ( MYT1L ), and 19p12 ( ZNF492 ) modified alkylating agent-related risks across ancestry groups, but AFR survivors with risk alleles experienced disproportionately greater risk of DM (AFR, variant ORs: 3.95-17.81; EUR, variant ORs: 2.37-3.32). Novel risk locus XNDC1N was identified in the first genome-wide DM rare variant burden association analysis in survivors (OR=8.65, 95% CI: 3.02-24.74, P=8.1×10 -6 ). Lastly, a general-population 338-variant multi-ancestry T2D polygenic risk score was informative for DM risk in AFR survivors, and showed elevated DM odds after alkylating agent exposures (quintiles: combined OR EUR =8.43, P=1.1×10 -8 ; OR AFR =13.85, P=0.033). This study supports future precision diabetes surveillance/survivorship care for all childhood cancer survivors, including those with AFR ancestry.

Ethnic-specific predictors of neurotoxicity among patients with pediatric acute lymphoblastic leukemia after high-dose methotrexate

BACKGROUND

High-dose methotrexate (HD-MTX; 5000 mg/m2 ) is an important component of curative therapy in many treatment regimens for high-risk pediatric acute lymphoblastic leukemia (ALL). However, methotrexate therapy can result in dose-limiting neurotoxicity, which may disproportionately affect Latino children. This study evaluated risk factors for neurotoxicity after HD-MTX in an ethnically diverse population of patients with ALL.

METHODS

The authors retrospectively reviewed the medical records of patients who were diagnosed with ALL and treated with HD-MTX at Texas Children's Cancer Center (2010-2017). Methotrexate neurotoxicity was defined as a neurologic episode (e.g., seizures or stroke-like symptoms) occurring within 21 days of HD-MTX that resulted in methotrexate treatment modifications. Mixed effects multivariable logistic regression was used to estimate the odds ratio (OR) and corresponding 95% confidence interval (CI) for the association between clinical factors and neurotoxicity.

RESULTS

Overall, 351 patients (58.1% Latino) who received 1183 HD-MTX infusions were evaluated. Thirty-five patients (10%) experienced neurotoxicity, 71% of whom were Latino. After adjusting for clinical risk factors, the authors observed that serum creatinine elevations ≥50% of baseline were associated with a three-fold increased odds (OR, 3.32; 95% CI, 0.98-11.21; p = .05) for neurotoxicity compared with creatinine elevation <25%. Notably, predictors of neurotoxicity differed by ethnicity. Specifically, Latino children experienced a nearly six-fold increase in neurotoxicity odds (OR, 5.80; 95% CI, 1.39-24.17; p = .02) with serum creatinine elevation ≥50% compared with creatinine elevation <25%.

CONCLUSIONS

The current findings indicate that serum creatinine elevations ≥50% may be associated with an increased risk for neurotoxicity among Latino children with ALL and may identify potential candidates for therapeutic or supportive care interventions.

Risk of bacterial bloodstream infection does not vary by central-line type during neutropenic periods in pediatric acute myeloid leukemia

BACKGROUND

Bloodstream infections (BSIs) are a frequent cause of morbidity in patients with acute myeloid leukemia (AML), due in part to the presence of central venous access devices (CVADs) required to deliver therapy.

OBJECTIVE

To determine the differential risk of bacterial BSI during neutropenia by CVAD type in pediatric patients with AML.

METHODS

We performed a secondary analysis in a cohort of 560 pediatric patients (1,828 chemotherapy courses) receiving frontline AML chemotherapy at 17 US centers. The exposure was CVAD type at course start: tunneled externalized catheter (TEC), peripherally inserted central catheter (PICC), or totally implanted catheter (TIC). The primary outcome was course-specific incident bacterial BSI; secondary outcomes included mucosal barrier injury (MBI)-BSI and non-MBI BSI. Poisson regression was used to compute adjusted rate ratios comparing BSI occurrence during neutropenia by line type, controlling for demographic, clinical, and hospital-level characteristics.

RESULTS

The rate of BSI did not differ by CVAD type: 11 BSIs per 1,000 neutropenic days for TECs, 13.7 for PICCs, and 10.7 for TICs. After adjustment, there was no statistically significant association between CVAD type and BSI: PICC incident rate ratio [IRR] = 1.00 (95% confidence interval [CI], 0.75-1.32) and TIC IRR = 0.83 (95% CI, 0.49-1.41) compared to TEC. When MBI and non-MBI were examined separately, results were similar.

CONCLUSIONS

In this large, multicenter cohort of pediatric AML patients, we found no difference in the rate of BSI during neutropenia by CVAD type. This may be due to a risk-profile for BSI that is unique to AML patients.

Absolute lymphocyte count recovery following initial acute myelogenous leukemia therapy: Implications for adoptive cell therapy

BACKGROUND

An adequate absolute lymphocyte count (ALC) is an essential first step in autologous chimeric antigen receptor (CAR) T-cell manufacturing. For patients with acute myelogenous leukemia (AML), the intensity of chemotherapy received may affect adequate ALC recovery required for CAR T-cell production. We sought to analyze ALC following each course of upfront therapy as one metric for CAR T-cell manufacturing feasibility in children and young adults with AML.

PROCEDURE

ALC data were collected from an observational study of patients with newly diagnosed AML between the ages of 1 month and 21 years who received treatment between the years of 2006 and 2018 at one of three hospitals in the Leukemia Electronic Abstraction of Records Network (LEARN) consortium.

RESULTS

Among 193 patients with sufficient ALC data for analysis, the median ALC following induction 1 was 1715 cells/μl (interquartile range: 1166-2388), with successive decreases in ALC with each subsequent course. Similarly, the proportion of patients achieving an ALC >400 cells/μl decreased following each course, ranging from 98.4% (190/193) after course 1 to 66.7% (22/33) for patients who received a fifth course of therapy.

CONCLUSIONS

There is a successive decline of ALC recovery with subsequent courses of chemotherapy. Despite this decline, ALC values are likely sufficient to consider apheresis prior to the initiation of each course of upfront therapy for the majority of newly diagnosed pediatric AML patients, thereby providing a window of opportunity for T-cell collection for those patients identified at high risk of relapse or with refractory disease.

Clinical and demographic factors contributing to asparaginase-associated toxicities in children with acute lymphoblastic leukemia

A total of 548 patients (age range: 1-22 years, 60.4% Hispanic, 55.8% male) diagnosed with acute lymphoblastic leukemia were reviewed for pegaspargase-associated hypersensitivity (14.8%), hyperbilirubinemia (9.7%), venous thromboembolism (VTE, 9.7%), and pancreatitis (5.3%). Odds ratios (OR) and 95% confidence intervals (CI) evaluated associations between clinical factors and each toxicity, cumulative number of toxicities, and toxicity clusters identified using k-mode analysis. Most (68.9%) did not experience any toxicity, 24.6% experienced one toxicity, and 6.3% two or more. Age >10 years was associated with hyperbilirubinemia (OR = 3.83; 95% CI: 1.64-8.95), pancreatitis (OR = 3.72; 95% CI: 1.29-10.68), VTE (OR = 4.65; 95% CI: 1.96-11.02), and cumulative toxicity burden (OR = 3.28, 95% CI: 1.97-5.47); high-risk therapy with hypersensitivity (OR 2.25; 95% CI 1.25-4.05); and overweight with cumulative toxicity burden (OR = 1.76, 95% CI: 1.20-2.57). Eight unique toxicity profiles were identified. Older age, overweight, and treatment intensity contribute to pegaspargase-associated toxicities.

Germline Genetic and Treatment-Related Risk Factors for Diabetes Mellitus in Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study and St Jude Lifetime Cohorts

PURPOSE

To characterize germline genetic risk factors of diabetes mellitus among long-term survivors of childhood cancer.

METHODS

Adult survivors of childhood cancer from the Childhood Cancer Survivor Study (CCSS) Original Cohort (n = 5,083; 383 with diabetes) were used to conduct a discovery genome-wide association study. Replication was performed using the CCSS Expansion (n = 2,588; 40 with diabetes) and the St Jude Lifetime (SJLIFE; n = 3,351; 208 with diabetes) cohorts. Risk prediction models, stratified on exposure to abdominal radiation, were calculated using logistic regression including attained age, sex and body mass index, diagnosis, alkylating chemotherapy, age at cancer diagnosis, and a polygenic risk score (PRS) on the basis of 395 diabetes variants from the general population. Area under the receiver operating characteristic curve (AUC) was calculated for models on the basis of traditional risk factors, clinical risk factors, and PRS.

RESULTS

There was a genome-wide significant association of rs55849673-A with diabetes among survivors (odds ratio, 2.9; 95% CI, 2.0 to 4.2; P = 3.7 × 10^-8), which is related to expression of ERCC6L2 in the Genotype-Tissue Expression project. The association of rs55849673-A was observed largely among survivors not exposed to abdominal radiation (odds ratio = 3.5, P = 1.1 × 10^-7) and the frequency of rs55849673-A was consistently higher among diabetic survivors in the CCSS Expansion and SJLIFE cohorts. Risk prediction models including traditional diabetes risk factors, clinical risk factors and PRS had an optimism-corrected AUC of 0.801, with an AUC of 0.751 in survivors treated with abdominal radiation versus 0.813 in survivors who did not receive abdominal radiation.

CONCLUSION

There is evidence for a novel locus of diabetes among survivors not exposed to abdominal radiation. Further refinement and validation of clinic-based risk prediction models for diabetes among long-term survivors of childhood cancer is warranted.

Rates of laboratory adverse events by course in paediatric leukaemia ascertained with automated electronic health record extraction: a retrospective cohort study from the Children's Oncology Group

BACKGROUND

Adverse events are often misreported in clinical trials, leading to an incomplete understanding of toxicities. We aimed to test automated laboratory adverse event ascertainment and grading (via the ExtractEHR automated package) to assess its scalability and define adverse event rates for children with acute myeloid leukaemia and acute lymphoblastic leukaemia.

METHODS

For this retrospective cohort study from the Children's Oncology Group (COG), we included patients aged 0-22 years treated for acute myeloid leukaemia or acute lymphoblastic leukaemia at Children's Healthcare of Atlanta (Atlanta, GA, USA) from Jan 1, 2010, to Nov 1, 2018, at the Children's Hospital of Philadelphia (Philadelphia, PA, USA) from Jan 1, 2011, to Dec 31, 2014, and at the Texas Children's Hospital (Houston, TX, USA) from Jan 1, 2011, to Dec 31, 2014. The ExtractEHR automated package acquired, cleaned, and graded laboratory data as per Common Terminology Criteria for Adverse Events (CTCAE) version 5 for 22 commonly evaluated grade 3-4 adverse events (fatal events were not evaluated) with numerically based CTCAE definitions. Descriptive statistics tabulated adverse event frequencies. Adverse events ascertained by ExtractEHR were compared to manually reported adverse events for patients enrolled in two COG trials (AAML1031, NCT01371981; AALL0932, NCT02883049). Analyses were restricted to protocol-defined chemotherapy courses (induction I, induction II, intensification I, intensification II, and intensification III for acute myeloid leukaemia; induction, consolidation, interim maintenance, delayed intensification, and maintenance for acute lymphoblastic leukaemia).

FINDINGS

Laboratory adverse event data from 1077 patients (583 from Children's Healthcare of Atlanta, 200 from the Children's Hospital of Philadelphia, and 294 from the Texas Children's Hospital) who underwent 4611 courses (549 for acute myeloid leukaemia and 4062 for acute lymphoblastic leukaemia) were extracted, processed, and graded. Of the 166 patients with acute myeloid leukaemia, 86 (52%) were female, 80 (48%) were male, 96 (58%) were White, and 132 (80%) were non-Hispanic. Of the 911 patients with acute lymphoblastic leukaemia, 406 (45%) were female, 505 (55%) were male, 596 (65%) were White, and 641 (70%) were non-Hispanic. Patients with acute myeloid leukaemia had the most adverse events during induction I and intensification II. Hypokalaemia (one [17%] of six to 75 [48%] of 156 courses) and alanine aminotransferase (ALT) increased (13 [10%] of 134 to 27 [17%] of 156 courses) were the most prevalent non-haematological adverse events in patients with acute myeloid leukaemia, as identified by ExtractEHR. Patients with acute lymphoblastic leukaemia had the greatest number of adverse events during induction and maintenance (eight adverse events with prevalence ≥10%; induction and maintenance: anaemia, platelet count decreased, white blood cell count decreased, neutrophil count decreased, lymphocyte count decreased, ALT increased, and hypocalcaemia; induction: hypokalaemia; maintenance: aspartate aminotransferase [AST] increased and blood bilirubin increased), as identified by ExtractEHR. 187 (85%) of 220 total comparisons in 22 adverse events in four AAML1031 and six AALL0923 courses were substantially higher with ExtractEHR than COG-reported adverse event rates for adverse events with a prevalence of at least 2%.

INTERPRETATION

ExtractEHR is scalable and accurately defines laboratory adverse event rates for paediatric acute leukaemia; moreover, ExtractEHR seems to detect higher rates of laboratory adverse events than those reported in COG trials. These rates can be used for comparisons between therapies and to counsel patients treated on or off trials about the risks of chemotherapy. ExtractEHR-based adverse event ascertainment can improve reporting of laboratory adverse events in clinical trials.

FUNDING

US National Institutes of Health, St Baldrick's Foundation, and Alex's Lemonade Stand Foundation.

Medical Outcomes, Quality of Life, and Family Perceptions for Outpatient vs Inpatient Neutropenia Management After Chemotherapy for Pediatric Acute Myeloid Leukemia

IMPORTANCE

Pediatric acute myeloid leukemia (AML) requires multiple courses of intensive chemotherapy that result in neutropenia, with significant risk for infectious complications. Supportive care guidelines recommend hospitalization until neutrophil recovery. However, there are little data to support inpatient over outpatient management.

OBJECTIVE

To evaluate outpatient vs inpatient neutropenia management for pediatric AML.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used qualitative and quantitative methods to compare medical outcomes, patient health-related quality of life (HRQOL), and patient and family perceptions between outpatient and inpatient neutropenia management. The study included patients from 17 US pediatric hospitals with frontline chemotherapy start dates ranging from January 2011 to July 2019, although the specific date ranges differed for the individual analyses by design and relative timing. Data were analyzed from August 2019 to February 2020.

EXPOSURES

Discharge to outpatient vs inpatient neutropenia management.

MAIN OUTCOMES AND MEASURES

The primary outcomes of interest were course-specific bacteremia incidence, times to next course, and patient HRQOL. Course-specific mortality was a secondary medical outcome.

RESULTS

Primary quantitative analyses included 554 patients (272 [49.1%] girls and 282 [50.9%] boys; mean [SD] age, 8.2 [6.1] years). Bacteremia incidence was not significantly different during outpatient vs inpatient management (67 courses [23.8%] vs 265 courses [29.0%]; adjusted rate ratio, 0.73; 95% CI, 0.56 to 1.06; P = .08). Outpatient management was not associated with delays to the next course compared with inpatient management (mean [SD] 30.7 [12.2] days vs 32.8 [9.7] days; adjusted mean difference, -2.2; 95% CI, -4.1 to -0.2, P = .03). Mortality during intensification II was higher for patients who received outpatient management compared with those who received inpatient management (3 patients [5.4%] vs 1 patient [0.5%]; P = .03), but comparable with inpatient management at other courses (eg, 0 patients vs 5 patients [1.3%] during induction I; P = .59). Among 97 patients evaluated for HRQOL, outcomes did not differ between outpatient and inpatient management (mean [SD] Pediatric Quality of Life Inventory total score, 70.1 [18.9] vs 68.7 [19.4]; adjusted mean difference, -2.8; 95% CI, -11.2 to 5.6). A total of 86 respondents (20 [23.3%] in outpatient management, 66 [76.7%] in inpatient management) completed qualitative interviews. Independent of management strategy received, 74 respondents (86.0%) expressed satisfaction with their experience. Concerns for hospital-associated infections among caregivers (6 of 7 caregiver respondents [85.7%] who were dissatisfied with inpatient management) and family separation (2 of 2 patient respondents [100%] who were dissatisfied with inpatient management) drove dissatisfaction with inpatient management. Stress of caring for a neutropenic child at home (3 of 3 respondents [100%] who were dissatisfied with outpatient management) drove dissatisfaction with outpatient management.

CONCLUSIONS AND RELEVANCE

This cohort study found that outpatient neutropenia management was not associated with higher bacteremia incidence, treatment delays, or worse HRQOL compared with inpatient neutropenia management among pediatric patients with AML. While outpatient management may be safe for many patients, course-specific mortality differences suggest that outpatient management in intensification II should be approached with caution. Patient and family experiences varied, suggesting that outpatient management may be preferred by some but may not be feasible for all families. Further studies to refine and standardize safe outpatient management practices are warranted.

Identifying relapses and stem cell transplants in pediatric acute lymphoblastic leukemia using administrative data: Capturing national outcomes irrespective of trial enrollment

INTRODUCTION

Our objectives were to design and validate methods to identify relapse and hematopoietic stem cell transplantation (HSCT) in children with acute lymphoblastic leukemia (ALL) using administrative data representing hospitalizations at US pediatric institutions.

METHODS

We developed daily billing and ICD-9 code definitions to identify relapses and HSCTs within a cohort of children with newly diagnosed ALL between January 1, 2004, and December 31, 2013, previously assembled from the Pediatric Health Information System (PHIS) database. Chart review for children with ALL at the Children's Hospital of Philadelphia (CHOP) and Texas Children's Hospital (TCH) was performed to establish relapse and HSCT gold standards for sensitivity and positive predictive value (PPV) calculations. We estimated incidences of relapse and HSCT in the PHIS ALL cohort.

RESULTS

We identified 362 CHOP and 314 TCH ALL patients in PHIS and established true positives by chart review. Sensitivity and PPV for identifying both relapse and HSCT in PHIS were > 90% at both hospitals. Five-year relapse incidence in the 10 150-patient PHIS cohort was 10.3% (95% CI 9.8%-10.9%) with 7.1% (6.6%-7.6%) of children underwent HSCTs. Patients in higher-risk demographic groups had higher relapse and HSCT rates. Our analysis also identified differences in incidences of relapse and HSCT by race, ethnicity, and insurance status.

CONCLUSIONS

Administrative data can be used to identify relapse and HSCT accurately in children with ALL whether they occur on- or off-therapy, in contrast with published approaches. This method has wide potential applicability for estimating these incidences in pediatric ALL, including patients not enrolled on clinical trials.

Sensor-Based Frailty Assessment in Survivors of Childhood Cancer: A Pilot Study

BACKGROUND

Survivors of childhood cancer (CCS) are at risk for early aging and frailty. Frailty in CCS has been assessed with established clinical criteria, a time-intensive approach requiring specialized training. There is an unmet need for cost-effective, rapid methods for assessing frailty in at-risk adolescent and young adult (AYA) CCS, which are scalable to large populations.

OBJECTIVES

To validate a sensor-based frailty assessment tool in AYA CCS, compare frailty status between CCS and controls, and assess the correlation between frailty and number of CCS comorbidities.

DESIGN, SETTING, AND PARTICIPANTS

Mean frailty index (MFI) was assessed by a frailty wrist sensor in 32 AYA CCS who were ≥1 year off therapy and in remission. Results were compared with 32 AYA controls without cancer or chronic disease.

MEASUREMENTS

Frailty assessments with and without a simultaneous cognitive task were performed to obtain MFI. Results were compared between cases and controls using a Student t test, and the number of pre-frail/frail subjects by Chi Square test. The contribution of radiation therapy (RT) exposure to MFI was assessed in a sub-analysis, and the correlation between the number of comorbidities and MFI was measured using the Pearson method.

RESULTS

MFI was strongly correlated with gait speed in AYA CCS. CCS were more likely to be pre-frail than controls without cancer history (p=0.032), and CCS treated with RT were more likely to be pre-frail than CCS not treated with RT (p<0.001). The number of comorbidities was strongly correlated with MFI (ρ=0.65), with a 0.028 increase in MFI for each added condition (p<0.001).

CONCLUSIONS

Results from this study support higher risk for frailty among CCS, especially those with multiple comorbidities or who were treated with RT. A wrist-worn sensor-based method is feasible for application in AYA CCS, and provides an opportunity for cost-effective, rapid screening of at-risk AYA CCS who may benefit from early interventions.

Improving reproducibility of left ventricular ejection fraction in pediatric oncology patients: less is more

Reproducible measurement of left ventricular (LV) systolic function by echocardiography is important to detect cancer therapy-related cardiac dysfunction (CTRCD). We hypothesized that limiting the number of imaging operators and use of a single vendor would improve reproducibility of these measures. A standard operating procedure (SOP) whereby LV measurements were standardized and a cardio-oncology imaging team (5 sonographers, 6 cardiologists) was established. All pediatric oncology patient echocardiograms were acquired on a single vendor platform. In total, 100 consecutive pre-SOP and 100 post-SOP studies were reviewed. LV end-diastolic dimension (LVEDD), posterior wall thickness (PW), shortening fraction (SF), and ejection fraction by Simpson's biplane (EF) were re-measured by 2 blinded readers, and compared to what was originally reported. Image quality was scored by number of LV segments imaged (grades 1-4). Inter-observer reproducibility pre/post-SOP was assessed with intra-class coefficient (α). Reducing the number of imaging operators improved image quality (Grade ≥ 3: 13% vs. 46%, p < 0.001). Reproducibility of PW and LVEDD marginally improved (PW: 0.78 to 0.82; LVEDD: 0.96 to 0.97), and SF improved significantly (α = 0.65 vs. 0.79, p < 0.001). Pre-SOP reproducibility of LV EF was poor (α = 0.65), but improved significantly post-SOP (α = 0.83, p < 0.001). Reproducibility of LV EF improved with higher image quality score. Limiting imaging operators and vendor platform for pediatric oncology echocardiograms improves image quality and reproducibility of LV EF. Establishing an SOP and a cardio-oncology echocardiography team may improve precision of measurements used to detect CTRCD.

Assessing the left atrium of childhood cancer survivors

Survivors of childhood cancer are at risk of cancer therapy-related cardiac dysfunction (CTRCD) characterized by systolic impairment, with little known about diastolic function. Left atrial strain (LAS) is a surrogate measure of left ventricular filling. We hypothesized that survivors (1) have lower LAS versus controls, and (2) survivors exposed to higher anthracycline dosage have even lower LAS. Cross-sectional study of 45 survivors exposed to anthracyclines ≥ 1 year after chemotherapy and 45 healthy controls. Echo variables included mitral spectral and tissue Doppler, left ventricular ejection fraction (LV EF), LV dimension, LA volume, LV global longitudinal strain (GLS), and LAS. Peak strain (Ɛ) and strain rate (SR) at three phases were obtained: atrial contraction (ac), reservoir (res), and conduit (con). Two sub-analyses of cancer survivors were performed: (1) those with anthracycline dosage ≥ 250 mg/m², and (2) those with Ɛres in the lowest quartile. On the whole, survivors had lower Ɛres and Ɛcon values. The majority of survivors had relatively normal LAS, while a subset had very low LAS values and were more likely to be older. Survivors exposed to ≥ 250 mg/m² anthracycline also had lower Ɛres than those < 250 mg/m². There were no differences in mitral spectral/tissue Doppler, LV dimension, left atrial volume, or GLS. A subset of childhood cancer survivors have lower LAS than their healthy counterparts, while most are essentially normal. Those exposed to higher anthracycline dosage have even lower Ɛres. Longitudinal study of LAS may prove useful in monitoring for CTRCD.

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.

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.

An overview of disparities in childhood cancer: Report on the Inaugural Symposium on Childhood Cancer Health Disparities, Houston, Texas, 2016

The Inaugural Symposium on Childhood Cancer Health Disparities was held in Houston, Texas, on November 2, 2016. The symposium was attended by 109 scientists and clinicians from diverse disciplinary backgrounds with interests in pediatric cancer disparities and focused on reviewing our current knowledge of disparities in cancer risk and outcomes for select childhood cancers. Following a full day of topical sessions, everyone participated in a brainstorming session to develop a working strategy for the continued expansion of research in this area. This meeting was designed to serve as a springboard for examination of childhood cancer disparities from a more unified and systematic approach and to enhance awareness of this area of need.

Improving Childhood Cancer Survivor Care Through Web-Based Platforms

Survivors of childhood cancer are at increased risk for late effects of cancer therapy, but evidence suggests that adherence to follow-up care is suboptimal. Here, we review the barriers to adherence, including those unique to childhood cancer survivors, and the rationale for distribution of a survivorship care plan. We also discuss advantages and potential limitations of delivering survivorship care plans via web-based platforms, and describe the unique features of one of these platforms, Passport for Care. A baseline survey directed toward survivors and conducted through Passport for Care found that a significant proportion of survivors are unaware of their specific health risks resulting from cancer and its treatment, and compared with their parents, are less afraid of the risks of recurrence and of cancer therapy-associated late effects (n = 528). Web-based platforms such as Passport for Care have enormous potential for improving access to health information, as well as for enhancing patient, family caregiver, and healthcare provider awareness of both risks of late effects and recommended surveillance. Results from this survey also suggest the potential utility of leveraging these tools to conduct additional research on consenting survivors.

Ethnic disparities relative to disease features and outcomes in children with acute myeloid leukemia

Hispanics with acute leukemias have poorer outcomes than non-Hispanic whites (NHWs), despite an increased likelihood of favorable prognostic features. We reviewed medical records from 167 children ages 0-18 years diagnosed with de novo AML over an 18-year period at Texas Children's Cancer Center, among whom 129 self-identified as Hispanic or NHW. Although Hispanics were significantly more likely to have the favorable prognostic cytogenetic feature t(8;21) (P = 0.04), the expected survival benefit was not observed. This lack of survival benefit was primarily due to significantly poorer event-free and overall survival among Hispanics treated with upfront stem cell transplantation after achieving first clinical remission (P = 0.008).

Germline mutations in shelterin complex genes are associated with familial glioma

Gliomas are the most common brain tumor, with several histological subtypes of various malignancy grade. The genetic contribution to familial glioma is not well understood. Using whole exome sequencing of 90 individuals from 55 families, we identified two families with mutations in POT1 (p.G95C, p.E450X), a member of the telomere shelterin complex, shared by both affected individuals in each family and predicted to impact DNA binding and TPP1 binding, respectively. Validation in a separate cohort of 264 individuals from 246 families identified an additional mutation in POT1 (p.D617Efs), also predicted to disrupt TPP1 binding. All families with POT1 mutations had affected members with oligodendroglioma, a specific subtype of glioma more sensitive to irradiation. These findings are important for understanding the origin of glioma and could have importance for the future diagnostics and treatment of glioma.

The adolescent and young adult with cancer: state of the art-- acute leukemias

Despite survival gains over the past several decades, adolescent and young adult (AYA) patients with both acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) demonstrate a consistent survival disadvantage. The AYA population exhibits unique disease and host characteristics, and further study is needed to improve their outcomes. This review will highlight distinctive aspects of disease biology in this population, as well as salient treatment-related toxicities including osteonecrosis, pancreatitis, thromboembolism, hyperglycemia, and infections. The impact of obesity and differences in drug metabolism and chemotherapy resistance will also be discussed, as well as optimal treatment considerations for the AYA population.

Absolute lymphocyte counts refine minimal residual disease-based risk stratification in childhood acute lymphoblastic leukemia

BACKGROUND

Several studies have demonstrated the prognostic utility of absolute lymphocyte count (ALC) during therapy for a range of malignancies, with low ALC associated with adverse outcome. Here we investigated whether ALC retained independent prognostic significance with respect to minimal residual disease (MRD) status in children with acute lymphoblastic leukemia (ALL).

PROCEDURE

We reviewed 171 cases of pediatric ALL treated on the Children's Oncology Group P9900 series of treatment trials. Variables analyzed included ALC at several time points during Induction, age at diagnosis, cytogenetics, initial white blood cell count, and MRD status at Day 29 of Induction (MRD-29).

RESULTS

We found high ALC at Induction Day 29 (ALC-29) to be an independent, clinically significant predictor of improved relapse-free and overall survival (OS). Patients with ALC-29 >1,500 cells/µl had a superior 6-year relapse-free survival (80 ± 4% vs. 62 ± 8%, P = 0.018) and overall survival (96 ± 2% vs. 74 ± 8%, P = 0.001). Moreover, ALC-29 identified distinct prognostic subgroups within cases stratified by MRD-29. In subjects with >0.01% MRD, ALC-29 > or <1,500 cells/µl had a significant 51% difference in 6-year OS (92 ± 7% vs. 41 ± 16%, P = 0.0001).

CONCLUSIONS

ALC, a readily obtainable test, constitutes a significant and independent prognostic factor in childhood ALL that may refine current MRD-based risk stratification algorithms and provide key prognostic information in settings where MRD determination is not feasible.

Neonatal alloimmune thrombocytopenia and neutropenia associated with maternal human leukocyte antigen antibodies

Neonatal thrombocytopenia or neutropenia may result from passive transfusion of maternally derived antibodies. Antibodies against platelet antigens are commonly associated with neonatal alloimmune thrombocytopenia (NAIT), and anti-neutrophil antibodies are frequently identified in alloimmune neonatal neutropenia (ANN). Combined alloimmune cytopenias in the newborn are rarely reported; even fewer reports document human leukocyte antigen (HLA) antibodies as a potential cause of neonatal thrombocytopenia or neutropenia. We describe neutropenia and thrombocytopenia in a newborn associated with markedly elevated maternal HLA antibodies in the absence of anti-neutrophil or anti-platelet antibodies to highlight consideration of HLA antibodies in the pathogenesis of ANN and NAIT.