St Jude Children's Research Research Articles

Genomic Determinants of Outcome in Acute Lymphoblastic Leukemia.

Although cure rates for childhood acute lymphoblastic leukemia (ALL) exceed 90%, ALL remains a leading cause of cancer death in children. Half of relapses arise in children initially classified with standard-risk (SR) disease. To identify genomic determinants of relapse in children with SR ALL, we performed genome and transcriptome sequencing of diagnostic and remission samples of children with SR (n = 1,381) or high-risk B-ALL with favorable cytogenetic features (n = 115) enrolled on Children's Oncology Group trials. We used a case-control study design analyzing 439 patients who relapsed and 1,057 who remained in complete remission for at least 5 years. Genomic subtype was associated with relapse, which occurred in approximately 50% of cases of PAX5-altered ALL (odds ratio [OR], 3.31 [95% CI, 2.17 to 5.03]; P = 3.18 × 10-8). Within high-hyperdiploid ALL, gain of chromosome 10 with disomy of chromosome 7 was associated with favorable outcome (OR, 0.27 [95% CI, 0.17 to 0.42]; P = 8.02 × 10-10; St Jude Children's Research Hospital validation cohort: OR, 0.22 [95% CI, 0.05 to 0.80]; P = .009), and disomy of chromosomes 10 and 17 with gain of chromosome 6 was associated with relapse (OR, 7.16 [95% CI, 2.63 to 21.51]; P = 2.19 × 10-5; validation cohort: OR, 21.32 [95% CI, 3.62 to 119.30]; P = .0004). Genomic alterations were associated with relapse in a subtype-dependent manner, including alterations of INO80 in ETV6::RUNX1 ALL, IKZF1, and CREBBP in high-hyperdiploid ALL and FHIT in BCR::ABL1-like ALL. Genomic alterations were also associated with the presence of minimal residual disease, including NRAS and CREBBP in high-hyperdiploid ALL. Genetic subtype, patterns of aneuploidy, and secondary genomic alterations determine risk of relapse in childhood ALL. Comprehensive genomic analysis is required for optimal risk stratification.

Impact of Age on Pharmacogenomics and Treatment Outcomes of B-Cell Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia (ALL) can occur across all age groups, with a strikingly higher cure rate in children compared with adults. However, the pharmacological basis of age-related differences in ALL treatment response remains unclear. Studying 767 children and 309 adults with newly diagnosed B-cell ALL enrolled on frontline trials at St Jude Children's Research Hospital, MD Anderson Cancer Center, the Alliance for Clinical Trials in Oncology, and the ECOG-ACRIN Cancer Research Group, we determined the ex vivo sensitivity of leukemia cells to 21 drugs. Twenty-three ALL molecular subtypes were identified using RNA sequencing. We systematically characterized the associations between drug response and ALL genomics in children, adolescents and young adults, and elderly adults. We evaluated the effect of age-related gene expression signature on ALL treatment outcomes. Seven ALL drugs (asparaginase, prednisolone, mercaptopurine, dasatinib, nelarabine, daunorubicin, and inotuzumab ozogamicin) showed differential activity between children and adults, of which six were explained by age-related differences in leukemia molecular subtypes. Adolescents and young adults showed similar patterns of drug resistance as older adults, relative to young children. Mercaptopurine exhibited subtype-independent greater sensitivity in children. Transcriptomic profiling uncovered subclusters within CRLF2-, DUX4-, and KMT2A-rearranged ALL that were linked to age and cytotoxic drug resistance. In particular, a subset of children had adult-like ALL on the basis of leukemia gene expression patterns across subtypes, despite their chronological age. Resistant to cytotoxic drugs, children with adult-like ALL exhibited poor prognosis in pediatric ALL trials, even after adjusting for age and minimal residual diseases. Our results provide pharmacogenomic insights into age-related disparities in ALL cure rates and identify leukemia prognostic features for treatment individualization across age groups.

Race and Ethnicity, Socioeconomic Factors, and Epigenetic Age Acceleration in Survivors of Childhood Cancer

Current research in epigenetic age acceleration (EAA) is limited to non-Hispanic White individuals. It is imperative to improve inclusivity by considering racial and ethnic minorities in EAA research. To compare non-Hispanic Black with non-Hispanic White survivors of childhood cancer by examining the associations of EAA with cancer treatment exposures, potential racial and ethnic disparity in EAA, and mediating roles of social determinants of health (SDOH). In this cross-sectional study, participants were from the St Jude Lifetime Cohort, which was initiated in 2007 with ongoing follow-up. Eligible participants included non-Hispanic Black and non-Hispanic White survivors of childhood cancer treated at St Jude Children's Research Hospital between 1962 and 2012 who had DNA methylation data. Data analysis was conducted from February 2023 to May 2024. Three treatment exposures for childhood cancer (chest radiotherapy, alkylating agents, and epipodophyllotoxin). DNA methylation was generated from peripheral blood mononuclear cell-derived DNA. EAA was calculated as residuals from regressing Levine or Horvath epigenetic age on chronological age. SDOH included educational attainment, annual personal income, and the socioeconomic area deprivation index (ADI). General linear models evaluated cross-sectional associations of EAA with race and ethnicity (non-Hispanic Black and non-Hispanic White) and/or SDOH, adjusting for sex, body mass index, smoking, and cancer treatments. Adjusted least square means (ALSM) of EAA were calculated for group comparisons. Mediation analysis treated SDOH as mediators with average causal mediation effect (ACME) calculated for the association of EAA with race and ethnicity. Among a total of 1706 survivors including 230 non-Hispanic Black survivors (median [IQR] age at diagnosis, 9.5 [4.3-14.3] years; 103 male [44.8%] and 127 female [55.2%]) and 1476 non-Hispanic White survivors (median [IQR] age at diagnosis, 9.3 [3.9-14.6] years; 766 male [51.9%] and 710 female [48.1%]), EAA was significantly greater among non-Hispanic Black survivors (ALSM = 1.41; 95% CI, 0.66 to 2.16) than non-Hispanic White survivors (ALSM = 0.47; 95% CI, 0.12 to 0.81). Among non-Hispanic Black survivors, EAA was significantly increased among those exposed to chest radiotherapy (ALSM = 2.82; 95% CI, 1.37 to 4.26) vs those unexposed (ALSM = 0.46; 95% CI, -0.60 to 1.51), among those exposed to alkylating agents (ALSM = 2.33; 95% CI, 1.21 to 3.45) vs those unexposed (ALSM = 0.95; 95% CI, -0.38 to 2.27), and among those exposed to epipodophyllotoxins (ALSM = 2.83; 95% CI, 1.27 to 4.40) vs those unexposed (ALSM = 0.44; 95% CI, -0.52 to 1.40). The association of EAA with epipodophyllotoxins differed by race and ethnicity (β for non-Hispanic Black survivors, 2.39 years; 95% CI, 0.74 to 4.04 years; β for non-Hispanic White survivors, 0.68; 95% CI, 0.05 to 1.31 years) and the difference was significant (1.77 years; 95% CI, 0.01 to 3.53 years; P for interaction = .049). Racial and ethnic disparities in EAA were mediated by educational attainment (<high school vs ≥college, ACME = 0.13; high school vs ≥college, ACME = 0.07; mediation = 22.71%) and ADI (ACME = 0.24; mediation = 22.16%). In this cross-sectional study of childhood cancer survivors, race and ethnicity moderated the association of EAA with epipodophyllotoxin exposure and racial and ethnic differences in EAA were partially mediated by educational attainment and ADI, indicating differential treatment toxic effects by race and ethnicity. These findings suggest that improving social support systems may mitigate socioeconomic disadvantages associated with even greater accelerated aging and reduce health disparities among childhood cancer survivors.

The burden of cardiovascular disease and risk for subsequent major adverse cardiovascular events in survivors of childhood cancer: a prospective, longitudinal analysis from the St Jude Lifetime Cohort Study

The effect of the increasing lifetime burden of non-major cardiovascular conditions on risk for a subsequent major adverse cardiovascular event among survivors of childhood cancer has not been assessed. We aimed to characterise the prevalence of major adverse cardiovascular events and their association with the cumulative burden of non-major adverse cardiovascular events in childhood cancer survivors. This is a longitudinal cohort study with participant data obtained from an ongoing cohort study at St Jude Children's Research Hospital: the St Jude Lifetime Cohort Study (SJLIFE). Prospective clinical follow-up was of 5-year survivors of childhood cancer who were diagnosed when aged younger than 25 years from 1962 to 2012. Age-frequency, sex-frequency, and race-frequency matched community-control participants completed a similar one-time clinical assessment. 22 cardiovascular events were graded using a St Jude Children's Research Hospital-modified version of the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03). Cumulative incidence and burden of the primary outcome of major adverse cardiovascular events (cardiomyopathy, myocardial infarction, stroke, and other cardiovascular-related mortality) were estimated. Rate ratios (RR) of the association of major adverse cardiovascular events with 22 non-major adverse cardiovascular events were estimated using multivariable piecewise-exponential regression adjusting for attained age, age at diagnosis, sex, race and ethnicity, treatment era, diagnosis of diabetes, and exposure to cardiotoxic cancer therapies. The St Jude Lifetime Cohort study is registered with ClinicalTrials.gov, NCT00760656, and is ongoing. 9602 5-year survivors of childhood cancer, and 737 community controls were included in the longitudinal follow-up (from Sept 13, 2007, to Dec 17, 2021). The median follow-up was 20·3 years (IQR 12·0-31·4) from the date of primary cancer diagnosis (4311 [44.9%] were females). By the age of 50 years (analysis stopped at age 50 years due to the low number of participants older than that age), the cumulative incidence of major adverse cardiovascular events among survivors was 17·7% (95% CI 15·9-19·5) compared with 0·9% (0·0-2·1) in the community controls. The cumulative burden of major adverse cardiovascular events in survivors was 0·26 (95% CI 0·23-0·29) events per survivor compared with 0·009 (0·000-0·021) events per community control participant. Increasing cumulative burden of grade 1-4 non-major adverse cardiovascular events was associated with an increased future risk of major adverse cardiovascular events (one condition: RR 4·3, 95% CI 3·1-6·0; p<0·0001; two conditions: 6·6, 4·6-9·5; p<0·0001; and three conditions: 7·7, 5·1-11·4; p<0·0001). Increased risk for major adverse cardiovascular events was observed with specific subclinical conditions (eg, grade 1 arrhythmias [RR 1·5, 95% CI 1·2-2·0; p=0·0017]), grade 2 left ventricular systolic dysfunction (2·2, 1·6-3·1; p<0·0001), grade 2 valvular disorders (2·2, 1·2-4·0; p=0·013), but not grade 1 hypercholesterolaemia, grade 1-2 hypertriglyceridaemia, or grade 1-2 vascular stenosis. Among an ageing cohort of survivors of childhood cancer, the accumulation of non-major adverse cardiovascular events, including subclinical conditions, increased the risk of major adverse cardiovascular events and should be the focus of interventions for early detection and prevention of major adverse cardiovascular events. The US National Cancer Institute and the American Lebanese Syrian Associated Charities.

Response of bilateral Wilms tumor to chemotherapy suggests histologic subtype and guides treatment.

Patients with bilateral Wilms tumor initially receive neoadjuvant chemotherapy to shrink the tumors and increase the likelihood of successful nephron-sparing surgery. Biopsy of poorly responding tumors is often done to better understand therapy resistance. The purpose of this retrospective, single-institution study was to determine whether initial chemotherapy response is associated with tumor histology, potentially obviating the need for biopsy or change in chemotherapy. Patients with synchronous bilateral Wilms tumors who underwent surgery at St Jude Children's Research Hospital from January 2000 to March 2022 were considered for this study. A mixed-effects logistic regression model was used to evaluate the likelihood of the tumor being stromal predominant, as predicted by tumor response to neoadjuvant chemotherapy. A total of 68 patients were eligible for this study. Tumors that increased in size had an odds ratio of 19.5 (95% confidence interval [CI] = 2.46 to 155.03) for being stromal predominant vs any other histologic subtype. Age at diagnosis was youngest in patients with stromal-predominant tumors, with a mean age of 18.8 (14.1) months compared with all other histologic subtypes (χ2 = 7.05, P = .07). The predictive value of a tumor growing combined with patient aged younger than 18 months for confirming stromal-predominant histology was 85.7% (95% CI = 57.18% to 93.5%). Tumors that increased in size during neoadjuvant chemotherapy were most frequently stromal-predominant bilateral Wilms tumor, especially in younger patients. Therefore, nephron-sparing surgery, rather than biopsy, or extension or intensification of neoadjuvant chemotherapy, should be considered for bilateral Wilms tumors that increase in volume during neoadjuvant chemotherapy, particularly in patients aged younger than 18 months.

COVID-19 in Pediatric Patients With Acute Lymphoblastic Leukemia or Lymphoma

COVID-19 in pediatric patients with acute lymphoblastic leukemia or lymphoma (ALL/LLy) has not been described in detail and may affect chemotherapy administration and long-term outcomes. To describe the clinical presentation of COVID-19 and chemotherapy modifications in pediatric patients with ALL/LLy. This is a retrospective case series of patients at St Jude Children's Research Hospital and its affiliate sites with newly diagnosed ALL/LLy who were treated on the Total XVII protocol (NCT03117751) between March 30, 2020, and June 20, 2022. Participants included patients aged 1 to 18 years who were receiving protocol chemotherapy. Acute symptoms and chemotherapy modifications were evaluated for 60 days after the COVID-19 diagnosis, and viral clearance, adverse events, and second SARS-CoV-2 infections were followed up during the 27-month study period. SARS-CoV-2; all patients were screened at least weekly and at symptom onset and/or after known exposure to SARS-CoV-2. Description of the spectrum of COVID-19 illness and chemotherapy modifications. Of 308 pediatric patients, 110 (36%) developed COVID-19 at a median age of 8.2 (IQR, 5.3-14.5) years. Sixty-eight patients (62%) were male. Most patients were in the continuation/maintenance phase of chemotherapy (101 [92%]). Severe disease was rare (7 [6%]) but was associated with older age, higher white blood cell counts at ALL/LLy diagnosis, lower absolute lymphocyte counts at COVID-19 diagnosis, abnormal chest imaging findings, and SARS-CoV-2 reinfection. Rare but serious thrombotic events included pulmonary embolism and cerebral venous sinus thrombosis (n = 1 for each). No multisystem inflammatory syndrome in children or death was seen. SARS-CoV-2 reinfection occurred in 11 patients (10%) and was associated with older age and with receiving standard or high-risk vs low-risk ALL/LLy therapy. Chemotherapy interruptions occurred in 96 patients (87%) and were longer for patients with severe disease, SARS-CoV-2 reinfection, and/or a COVID-19 diagnosis during the pre-Omicron variant period vs the post-Omicron period (after December 27, 2021). In this case series of COVID-19 in pediatric patients with ALL/LLy, severe COVID-19 was rare, but chemotherapy administration was affected in most patients. Long-term studies are needed to establish the outcomes of COVID-19 in this population.

Impact of Cytarabine Pharmacogenomics on Survival of Adolescent and Young Adults with AML and Its Clinical Relevance in Black Patients

Cytarabine (also known as ara-C) has been the mainstay of AML chemotherapy for both pediatric and adult patients (pts) since 1970s, and when given in combination with anthracycline it induces remission in ~60% of adult and 80% of pediatric pts. However, almost ~40% of pts relapse. Cytarabine is a prodrug requiring activation to ara-CTP for its antileukemic effect. Our group has been investigating the relevance of cytarabine pharmacogenomics and recently reported a pharmacogenomics-based polygenic score (ACS10) that includes 10 SNPs spanning 9 genes within metabolic pathway of cytarabine. ACS10 is predictive of intracellular levels of ara-CTP as well as outcome in pediatric AML pts enrolled in multiple clinical trials led by St Jude Children's Research Hospital and Children's Oncology Group (Elsayed et al, JCO 2022;40:772-3). Overall, pediatric AML pts with ACS10 low (≤0), had inferior outcomes compared with ACS10 high pts. Thus far, the ACS10 score has not been tested for its performance in adult AML, especially adolescent and young adult (AYA) AML pts. We hypothesized that ACS10 might be predictive of chemotherapy resistance in this defined pt population that is commonly treated with intensive induction therapy. Moreover, as several SNPs included in ACS10 show ancestry-enrichments, we speculated whether this might help explain the high resistance to treatment recently observed in Black AYA AML pts. A total of 406 newly diagnosed AYA AML pts (age 17-39y, median: 30y), similarly treated in 8 Alliance for Clinical Trials in Oncology frontline protocols were included in the study. All pts had centrally reviewed cytogenetics, targeted gene mutation profiling and SNP data (Illumina 2.5 omni array, see Walker et al, Leukemia 2019;33:771-5). ACS10 score was calculated for each pt using the equation defined by Elsayed et al (&amp;gt;0, ACS10 high; ≤0, ACS10 low) and Kaplan-Meier method and the log-rank test was used for survival analysis and Fisher's exact test was used for frequency comparison. Two hundred eighty-three pts were ACS10 high and 123 pts were ACS10 low. Though not statistically significant, ACS10 low pts tended to have a shorter overall survival (OS) compared with ACS10 high pts (p=.11). Restricting the analysis to those who received chemotherapy only (excluding allogeneic transplant recipients), showed that ACS10 low group had significantly shorter OS compared with ACS10 high group (p=.03). Further, event-free survival (EFS) was shorter (3y rates, 32% vs. 42%, p=0.09) and number of early deaths (death within 30 days of treatment initiation) was higher (5% vs 1%, p=.07) in ACS10 low pts. Given that the majority of patients received etoposide as part of the induction regimen, analysis within this subset showed ACS10 high pts having higher complete remission (CR) rates (85% vs 72%, p=.05) and longer EFS and OS compared with ACS10 low pts (EFS, 3y rates, 41% vs 28%, p=.02; OS, 3y rates, 54% vs 32%, p=.007). We have previously shown significant difference in abundance of ACS10 low by race/ethnicity in pediatric AML, 70% of Black pts being ACS10 low as compared with only 30% of White pts. Similarly, the current cohort showed significant differences in ACS10 score groups by race/ethnicity: of 32 Black pts included in the analysis, 27 (84%) were ACS10 low and only 5 (16%) were ACS10 high. Given the enrichment of the racial-ethnic survival disparity in AYA pts (Larkin et al, Blood Adv 2022;6:5570-81), we further investigated the impact of ACS10 on survival of Black AYA pts. Though limited by numbers, we observed worse OS (p=0.05) of ACS10 low group, which comprised 80% of Black pts. We show the impact of cytarabine pharmacogenomics and its relevance in AYA AML pts. Consistent with the results in pediatric AML, pts with low ACS10 score, which is reflective of lower cytarabine activation and intracellular ara-CTP accumulation, had worse outcome than pts with high ACS10 score. Further, low ACS10 score was highly abundant in Black compared to White AYA AML pts. Given the low CR rates, high relapse rates and inferior survival of Black pts, our results imply cytarabine pharmacogenomics as a possible crucial contributor. In conclusion, given that cytarabine is the backbone of AML chemotherapy and is used as a frontline agent in essentially all induction regimens, our results highlight the need for in-depth evaluation of ACS10 score in AML that may open opportunities to improve treatment response in AYA AML.

Deficit Accumulation Index and Biological Markers of Aging in Survivors of Childhood Cancer

Survivors of childhood cancer experience premature aging compared with community controls. The deficit accumulation index (DAI) uses readily available clinical data to measure physiological age in survivors; however, little data exist on how well deficit accumulation represents underlying biological aging among survivors of cancer. To examine the associations between the DAI and epigenetic age acceleration (EAA) and mean leukocyte telomere length (LTL). This cross-sectional study analyzed data from the St Jude Lifetime Cohort, an assessment of survivors of childhood cancer who were treated at St Jude Children's Research Hospital in Memphis, Tennessee. Data were collected between 2007 and 2016, assayed between 2014 and 2019, and analyzed between 2022 and 2023. Participants were adult survivors who were diagnosed between 1962 and 2012 and who survived 5 years or more from time of diagnosis. The analyses were restricted to survivors with European ancestry, as there were too few survivors with non-European ancestry. The DAI included 44 aging-related items, such as chronic health conditions and functional, psychosocial, and mental well-being. Item responses were summed and divided by the total number of items, resulting in a ratio ranging from 0 to 1. These DAI results were categorized based on reported associations with hospitalization and mortality: low, defined as a DAI less than 0.2; medium, defined as a DAI of 0.2 to less than 0.35; and high, defined as a DAI of 0.35 or higher. Genome-wide DNA methylation was generated from peripheral blood mononuclear cell-derived DNA. The EAA was calculated as the residuals from regressing the Levine epigenetic age on chronological age. The mean LTL was estimated using whole-genome sequencing data. This study included 2101 survivors of childhood cancer (1122 males [53.4%]; mean [SD] age, 33.9 [9.1] years; median [IQR] time since diagnosis, 25.1 [18.7-31.9] years) with European ancestry. Compared with survivors in the low DAI group, those in the high DAI group experienced 3.7 more years of EAA (β = 3.66; 95% CI, 2.47-4.85; P < .001), whereas those in the medium DAI group experienced 1.8 more years of EAA (β = 1.77; 95% CI, 0.84-2.69; P < .001), independent of treatment exposures. The EAA and DAI association was consistent across 3 common diagnoses (acute lymphoblastic leukemia, Hodgkin lymphoma, and central nervous system tumors) and across chronological age groups. For example, among acute lymphoblastic leukemia survivors, those in the medium DAI group (β = 2.27; 95% CI, 0.78-3.76; P = .001) experienced greater EAA vs those in the low DAI group. Similarly, among survivors younger than 30 years, the high DAI group experienced 4.9 more years of EAA vs the low DAI group (β = 4.95; 95% CI, 2.14-7.75; P < .001). There were no associations between mean LTL residual and the DAI. This cross-sectional study of survivors of childhood cancer showed that the DAI was associated with EAA, suggesting an underlying biological process to the accumulation of deficits. Both the DAI and EAA were effective at identifying aging phenotypes, and either may be used to measure aging and response to interventions targeting aging pathways.

Characteristics of COVID-19 Infections and Severe Outcomes in a Multinational Study in Latin America During the Circulation Period of the Delta Variant in the Pediatric Population

Abstract Background SARS-CoV-2 infection had specific characteristics in the pediatric population described in previous studies. These clinical features included specific COVID-19 presentation, antibiotic usage, and predictors of disease severity. In addition to patient related factors, external influences could affect COVID-19 outcomes. The features of children with COVID-19 of five Latin American countries were described. Study participants were members of the Prevencionistas e Infectólogos para Cáncer Pediátrico en América Latina (PRINCIPAL) Network of the Global Infectious Diseases Program at St Jude Children's Research Hospital. This study aims to analyze the differences between patients with non-severe and severe disease when the circulation of the Delta variant was predominant, and few children had received SARS-CoV-2 vaccines. Methods This is a retrospective, observational, multinational study that included children with a confirmed diagnosis of COVID-19 between January 2021 and January 2022. Epidemiological, clinical, and treatment characteristics are described and compared between patients with severe and non-severe disease. Frequencies and percentages are presented as well as median and interquartile ranges (IQR). Comparisons were made using the chi-squared test for proportions and the Wilcoxon test for nonparametric quantitative variables. Results 745 patients were included. Patients had a median age of 51 (13-139) months, 194 (26%) had comorbidities, and 701 (94%) presented with symptomatic disease. Fever was present in 524 (74.8%) patients, respiratory symptoms in 550 (78.5%), followed by gastrointestinal manifestations in 218 (31.1%). X-ray findings were abnormal in 175/362 patients, with interstitial infiltrates being the most common finding, 123 (70.7%). Almost a third of patients (29%) received an antibiotic; ceftriaxone was most frequently prescribed in 123/216 cases. Of 745 patients, 526 (70.8%) were hospitalized, of which 165 (31.4%) required PICU admission. Patients presenting with severe disease and requiring PICU admission we more likely to have a comorbidity, 128 (22%) vs. 66 (40%), p&amp;lt;0.001. Mucocutaneous findings or adenitis were more frequently described in severe cases, 19 (11.5) vs. 18 (5.0%), p=0.007. Regarding laboratory results, low lymphocytes 2445 vs. 1676 (p&amp;lt;0.001) and low platelets 294,000 vs. 250,000 (p=0.0002) were most common in patients with severe disease. The proportion of patients with lymphocytopenia was also higher in those with severe disease, 39% vs. 52% p= 0.010. Not surprisingly, antibiotic usage (broad and narrow spectrum) was higher in patients admitted to the PICU (32 vs. 16.5%) p=0.001, despite no significant difference in the frequency of bacterial coinfection (5.56% vs. 9.7% p=0.081) when compared to patients with non-severe disease. Specific treatment strategies were more frequent in PICU patients (39.1% vs. 72.1%) p&amp;lt;0.001, and steroids were the most frequently used drug, 35.2% vs. 70.7% (p&amp;lt;0.001). Table 1. Conclusions Regardless of the variant, COVID-19 is an important cause of hospitalization in children. Fever, respiratory and gastrointestinal symptoms are the most frequent manifestations in children. Despite the low frequency of bacterial coinfection, a high proportion of antibiotic usage is described. Compared to recent publications, mucocutaneous involvement, lower lymphocyte and platelet counts, and higher inflammatory markers were more frequently found in admissions to the PICU. Currently, with higher vaccine coverage and more comprehensive knowledge of the disease, optimization of pediatric COVID-19 management is expected, especially concerning antibiotic use. It is essential to continue multicenter surveillance of the behavior of COVID-19 in the pediatric population.

Cumulative burden of late, major surgical intervention in survivors of childhood cancer: a report from the Childhood Cancer Survivor Study (CCSS) cohort.

Multimodal cancer therapy places childhood cancer survivors at increased risk for chronic health conditions, subsequent malignancies, and premature mortality as they age. We aimed to estimate the cumulative burden of late (>5 years from cancer diagnosis), major surgical interventions among childhood cancer survivors, compared with their siblings, and to examine associations between specific childhood cancer treatments and the burden of late surgical interventions. We analysed data from the Childhood Cancer Survivor Study (CCSS), a retrospective cohort study with longitudinal prospective follow-up of 5-year survivors of childhood cancer (diagnosed before age 21 years) treated at 31 institutions in the USA, with a comparison group of nearest-age siblings of survivors selected by simple random sampling. The primary outcome was any self-reported late, major surgical intervention (defined as any anaesthesia-requiring operation) occurring 5 years or more after the primary cancer diagnosis. The cumulative burden was assessed with mean cumulative counts (MCC) of late, major surgical interventions. Piecewise exponential regression models with calculation of adjusted rate ratios (RRs) evaluated associations between treatment exposures and late, major surgical interventions. Between Jan 1, 1970, and Dec 31, 1999, 25 656 survivors were diagnosed (13 721 male, 11 935 female; median follow-up 21·8 years [IQR 16·5-28·4]; median age at diagnosis 6·1 years [3·0-12·4]); 5045 nearest-age siblings were also included as a comparison group. Survivors underwent 28 202 late, major surgical interventions and siblings underwent 4110 late, major surgical interventions. The 35-year MCC of a late, major surgical intervention was 206·7 per 100 survivors (95% CI 202·7-210·8) and 128·9 per 100 siblings (123·0-134·7). The likelihood of a late, major surgical intervention was higher in survivors versus siblings (adjusted RR 1·8, 95% CI 1·7-1·9) and in female versus male survivors (1·4; 1·4-1·5). Survivors diagnosed in the 1990s (adjusted RR 1·4, 95% CI 1·3-1·5) had an increased likelihood of late surgery compared with those diagnosed in the 1970s. Survivors received late interventions more frequently than siblings in most anatomical regions or organ systems, including CNS (adjusted RR 16·9, 95% CI 9·4-30·4), endocrine (6·7, 5·2-8·7), cardiovascular (6·6, 5·2-8·3), respiratory (5·3, 3·4-8·2), spine (2·4, 1·8-3·2), breast (2·1, 1·7-2·6), renal or urinary (2·0, 1·5-2·6), musculoskeletal (1·5, 1·4-1·7), gastrointestinal (1·4, 1·3-1·6), and head and neck (1·2, 1·1-1·4) interventions. Survivors of Hodgkin lymphoma (35-year MCC 333·3 [95% CI 320·1-346·6] per 100 survivors), Ewing sarcoma (322·9 [294·5-351·3] per 100 survivors), and osteosarcoma (269·6 [250·1-289·2] per 100 survivors) had the highest cumulative burdens of late, major surgical interventions. Locoregional surgery or radiotherapy cancer treatment were associated with undergoing late surgical intervention in the same body region or organ system. Childhood cancer survivors have a significant burden of late, major surgical interventions, a late effect that has previously been poorly quantified. Survivors would benefit from regular health-care evaluations aiming to anticipate impending surgical issues and to intervene early in the disease course when feasible. US National Institutes of Health, US National Cancer Institute, American Lebanese Syrian Associated Charities, and St Jude Children's Research Hospital.

Pharmacotypes across the Genomic Landscape of Pediatric Acute Lymphoblastic Leukemia and Impact on Treatment Response

INTRODUCTION The current paradigm of risk stratification in childhood acute lymphoblastic leukemia (ALL) utilizes a combination of clinical features, leukemia somatic genomics and early treatment response as measured by minimal residual disease (MRD). Although ALL subtypes and MRD are strongly related to treatment outcomes, the pharmacological basis of their prognostic impact remains incompletely understood. Therefore, we sought to characterize pharmacotypes (drug sensitivities) across the complete spectrum of ALL molecular subtypes and determine their association with in vivo treatment response and survival outcomes. METHODS This was a prospective study of 805 children with newly-diagnosed ALL from Total Therapy XV, XVI, and XVII trials at St Jude Children's Research Hospital. We performed ex vivo pharmacotyping of 18 drugs on primary ALL diagnostic blasts to determine drug sensitivities (LC50 - dose required to kill 50% of leukemia cells). RNA-sequencing was performed to derive molecular subtype. We then evaluated the associations of drug LC50 with clinical features, ALL subtype, MRD, and event-free survival (Figure 1). RESULTS We analyzed 5,447 drug measurements across 23 ALL subtypes. LC50s of prednisolone, asparaginase, and mercaptopurine were associated with age, and/or with leukocyte count at diagnosis. Sensitivities to 14 of 18 drugs varied across ALL molecular subtypes. For cytotoxic agents, B-ALL subtypes with favorable prognosis (ETV6-RUNX1 and hyperdiploidy) exhibited greatest sensitivity to asparaginase and glucocorticoids, whereas high-risk subtypes (KMT2A, BCR-ABL1, and BCR-ABL1-like) were resistant. Novel subtypes DUX4 and ETV6-RUNX1-like ALL showed significant resistance to cytotoxic drugs. For targeted agents, hyperdiploid ALL was most sensitive to venetoclax, whereas TCF3-PBX1, BCR-ABL1, and T-ALL were dasatinib-sensitive. The poor-prognosis ETP-ALL was resistant to most cytotoxic drugs compared to T-ALL. Although BCR-ABL1, BCR-ABL1-like, and CRLF2 are closely related transcriptionally, these three subtypes had distinctive drug sensitivity profiles. In B-ALL, sensitivities of prednisolone, asparaginase, dexamethasone, cytarabine and thiopurines were positively correlated with MRD. By contrast, these drugs were not correlated with MRD in T-ALL. Instead, sensitivities of dasatinib and nelarabine correlated positively, and venetoclax negatively, with MRD in T-ALL. Finally, we classified patients into six functional clusters based on ALL pharmacotypes, each with distinct patterns of somatic genomic aberrations and MRD response. Drug sensitivity cluster was significantly associated with event-free survival, even after adjusting for MRD. Importantly, pharmacotyping identified a T-ALL subset with poor prognosis under conventional chemotherapy but also with unique sensitivity to targeted agents, pointing to therapeutic intervention to improve survival in this group. CONCLUSIONEx vivo drug sensitivities vary widely across ALL subtypes and strongly influence in vivo MRD. Our study comprehensively described pharmacological heterogeneity of ALL and the association of drug sensitivities with survival outcomes, providing insight into the pharmacological basis of inter-patient variability in ALL treatment outcomes and highlighting opportunities for individualizing therapy for this blood cancer. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

EARLY T-CELL PRECURSOR ACUTE LYMPHOBLASTIC LEUKEMIA IN CHILDHOOD

Early T-cell precursor (ETP) ALL accounts for 10% to 15% of T-ALL, which arises from an early T-cell lineage clone with aberrant expression of myeloid and/or early progenitor cell markers (1,2). ETPs are a subset of thymocytes representing recent immigrants from the bone marrow to the thymus, they retain multilineage differentiation potential, suggesting their direct derivation from hematopoietic stem cells (3). ETP-ALL, which was first reported by Coustan-Smith in 2009, largely overlaps with the pro-T subtype of the EGIL classification; its special diagnostic criteria in immunophenotypic screening are the absence of CD1a and CD8 expression, the absence or weak expression of CD5, and the presence of strong positive for at least one of CD34, CD117, HLADR, CD13, CD33, CD11b, and CD65 (2,4-6). In case of strong positivity of CD5, at least two of the latter must be strong positive (6). There is also novel evidence that the myeloid marker CD371 may be positive in ETP (6). The genetic features of ETP-ALL are similar to those of hematopoietic stem cells and myeloid progenitor cells. The genomic mutations of ETP-ALL are enriched in hematopoietic transcriptional regulators (such as BCL11B, ETV6, RUNX1, biallelic WT1, and GATA3), epigenetic factors (such as histone modification, including PHF6, CTCF, EED, EZH2, SUZ12, and SETD2), and signaling genes (such as activation JAK-STAT, IL-7R and RAS signaling pathway, including JAK1, JAK3, IL7R, SH2B3, NRAS, KRAS, FLT3, NF1, and PTPN11). ETP-ALL has a lower frequency of classical T-ALL genetic alterations such as NOTCH1/FBXW7/CDKN2A mutations and a higher prevalence of FLT3, NRAS/KRAS, DNMT3A, IDH1, IDH2, JAK3, and ETV6 mutations (1,2,5). ETP-ALL was initially thought to have a poor prognosis, but the opinions on it vary (2,3,7). ETP ALL is often corticosteroid resistant and a high percentage of ETP ALL patients have detectable MRD at day 29 including many induction failures (1,2,7,8). No difference in OS was observed in the COG AALL0434 study and UKALL 2003 trial between the patients with ETP-ALL and typical T-ALL (4,9). Therefore, it is important to continue with conventional therapy in ETP-ALL patients who have poor end-induction response; MRD based therapeutic approach is recommanded (7,10). Patients with ETP-ALL had high risk of hematological relapse treated at St Jude Children's Research Hospital (3). For relapsed and refractory patients, the use of acute myeloid leukemia-oriented therapies such as FLAG-IDA regimen or targeted agents may be of benefit for some patients, including FLT3 inhibitors, tyrosine kinase inhibitors, BCL-2 inhibitors such as venetoclax, or JAK/STAT inhibitors in patients with JAK mutations or fusions (1,2,4,5,7).

Parental Preferences Surrounding Timing and Content of Consent Conversations for Clinical Germline Genetic Testing Following a Child's New Cancer Diagnosis.

Clinical genomic testing is increasingly being used to direct pediatric cancer care. Many centers are interested in offering testing of tumors and paired germline tissues at or near the time of cancer diagnosis. We conducted this study to better understand parent preferences surrounding timing and content of consent conversations for clinical germline genetic testing of their children with cancer as a part of real-time cancer care. A seven-question survey developed by the Division of Cancer Predisposition and collaborators at St Jude Children's Research Hospital (St Jude) was distributed to members of the St Jude Patient Family Advisory Council, which included parents of childhood cancer survivors and bereaved parents whose children with cancer had died. Parents were asked to provide free text comments after each question. Qualitative methods were used to derive codes from parent comments, and survey results were depicted using descriptive statistics. The survey was completed by 172 parents. Ninety-three (54%) endorsed an approach for consent conversations ≥ 1 month after cancer diagnosis, whereas 58 (34%) endorsed an approach at 1-2 weeks and 21 (12%) at 1-2 days. Needing time to adjust to a new or relapsed cancer diagnosis and feeling overwhelmed were frequent themes; however, parents acknowledged the urgency and importance of testing. Parents desired testing of as many cancer-related genes as possible, with clinical utility the most important factor for proceeding with testing. Most parents (75%) desired germline results to be disclosed in person, preferably by a genetic counselor. Parents described urgency and benefits associated with germline testing, but desired flexibility in timing to allow for initial adjustment after their child's cancer diagnosis.

New strategies for standardised and appropriate access to a complete acute lymphocytic leukaemia diagnostic panel for children in Mexico: an observational study

Approximately 50% of all childhood cancer cases in Mexico are acute lymphocytic leukaemia. Survival rates are suboptimal when compared with those in high-income countries, and poor access to standardised testing and treatment has been identified as a contributing factor. Mexico in Alliance with St Jude (MAS) is a multisite intersectoral collaboration created in 2016 to improve childhood cancer outcomes. MAS conducted a retrospective analysis of childhood acute lymphocytic leukaemia where diagnostic disparities and risk-group classification emerged as a challenge; 419 (72%) of 578 of patients with confirmed acute lymphocytic leukaemia did not have access supporting fluorescent in-situ hybridisation (FISH) testing and 226 (39%) of 578 patients did not have minimal residual disease evaluation. FISH results were reported in a median of 15 days (SD 17) and cytogenetic results were reported after a median of 22 days (SD 27). In response, MAS launched The Bridge Project, in 2019, to improve access, accuracy, and timeliness of diagnostic information for children with acute lymphocytic leukaemia in Mexico. A consensus-derived standardised diagnostic panel for children aged 0-18 years with suspected acute lymphocytic leukaemia was developed, including morphology, immunophenotype, karyotype, FISH, DNA index, and minimal residual disease evaluation at two timepoints: day 15 and after consolidation. Participating centres shipped diagnostic samples to a single central laboratory. Paediatric oncologists, nurses, clinical research coordinators, and laboratory technicians held weekly meetings for quality improvement. The Bridge Project has benefited 255 children by providing consistent access to a comprehensive diagnostic panel. 556 (94%) of 591 samples arrived within the target timeframe (≤48 h). Immunophenotype, karyotype, DNA index, FISH, and minimal residual disease access increased from 97%, 76%, 77%, 28%, and 61%, respectively, to 100%. The single central laboratory produced flow cytometry results (immunophenotype and minimal residual disease) and FISH results within 5 days and karyotype results within 13 days of sample arrival. Many structural and logistical challenges were successfully addressed through multidisciplinary and intersectoral collaboration. Eleven additional institutions joined the project in 2022, up from five in 2021. Timely access to standard specialised diagnostic testing for children with suspected acute lymphocytic leukaemia following a centralised approach is possible in lower-resource settings through multisite intersectoral collaboration. This synergistic action is benefiting children by providing timely access to a comprehensive diagnostic panel and serves as an example of health system resilience. Fundación Gonzalo Río Arronte (Mexico City, Mexico); Casa de la Amistad para niños con Cáncer (Mexico City, Mexico); St Jude Children's Research Hospital (Memphis, TN, USA).

Defining availability of 100 essential diagnostic items for children with cancer and gaps in implementing WHO recommendations: Global CEDx Working Group survey

WHO has established recommendations to guide governments' prioritisation of essential diagnostic tests, technologies, and priority medical devices for patients with cancer. Despite many countries committing to expanding resources for children with cancer since the WHO Global Initiative for Childhood Cancer was launched in 2018, data on the availability of essential diagnostics and on local awareness and adoption of WHO recommendations in low-income and middle-income countries are scarce. A purposive group of providers and policy makers was invited to review national interventions for access to diagnostics as part of their national cancer control plan or involvement in the WHO Global Initiative for Childhood Cancer. More than 800 diagnostic items (ie, diagnostic tests and diagnostic devices or equipment) from WHO recommendations for priority medical devices for cancer and essential in-vitro diagnostics list were iteratively summarised into 100 items relevant for children with cancer. A survey (in English, Spanish, French, and Russian) was developed to assess diagnostics availability and COVID-19 impact on access; out-of-pocket needs, or financial burden on families to pay for diagnostics; perception of the WHO recommendations with respect to completeness and relevance, use and usefulness for children with cancer; and factors affecting recommendation adoption and implementation. 380 participants from 16 low-income and middle-income countries in six WHO regions (Costa Rica, Dominican Republic, El Salvador, Ghana, Guatemala, Haiti, Honduras, Morocco, Myanmar, Nicaragua, Panama, Peru, Philippines, Sri Lanka, Ukraine, and Zambia), were invited. The median response rate across the 16 countries was 80%. 231 (80%) of 289 eligible respondents were multidisciplinary clinicians (including 101 paediatric haematologist-oncologists), and 58 (20%) self-identified primarily as administrators, non-governmental organisation representatives, and policy makers. Although some diagnostic items were not available in all settings, disparities were evident. Diagnostic items were significantly more available in the private than in the public setting across all three categories of laboratory and pathology (+25%), surgery and anaesthesia (+19%), and imaging (+43%; p<0·0015 for all categories). Most respondents indicated that at least one in four patients were affected by varying availability of diagnostic items, and that families paid out-of-pocket for essential diagnostic items. Top-ranked priorities by respondents included addressing access to advanced and basic diagnostics, delays in tests, and families' need to pay out-of-pocket. 119 (85%) of 140 eligible respondents considered that the 100 distilled core items reflected a complete list for laboratory and pathology, surgery and anaesthesia, and imaging. Although 69 (87%) of 79 respondents and 155 (90%) of 172 respondents found WHO recommendations useful and relevant, 228 (83%) of 276 had little previous familiarity with the recommendations, and only 82 (29%) of 278 had previously used them, mainly as personal references. Top factors affecting adoption and implementation of WHO recommendations included awareness and ease of extracting and applying recommendations to childhood cancer and to local contexts. This study established the availability of a core set of 100 essential diagnostic items recommended by WHO in low-income and middle-income countries in different phases of expanding access to care for children with cancer. A scarcity of essential laboratory and pathology, surgery and anaesthesia, and imaging diagnostics in all settings were identified, as well as a disproportionate lack of access for patients in the public setting, further disrupted by the COVID-19 pandemic. This study explored local awareness and factors affecting adoption and implementation of WHO recommendations and priorities for policy action. Our findings point to the utility of an essential diagnostics list for children analogous to WHO's essential medicines list. American Lebanese Syrian Associated Charities and St Jude Children's Research Hospital.

WHO and St Jude Children's Research Hospital announce childhood cancer medicines initiative.

On December 13, 2021, WHO and St Jude Children's Research Hospital jointly announced the launch of a new initiative to increase the supply of paediatric cancer medicines to low-income and middle-income countries (LMICs). The Global Platform for Access to Childhood Cancer Medicines will receive US$200 million in funding from St Jude Children's Research Hospital over the next 6 years. The platform aims to provide safe and effective cancer medication to approximately 120 000 children worldwide in 2022–27, with the expectation of a subsequent scale-up.

Cancer care for displaced children in Lebanon.

Lebanon is a small country on the Mediterranean Sea that has been plagued for decades by civil war and internal strife, which result from regional wars and power struggles. Most of the Lebanese population has access to national governmental health-care plans, but these are inadequate to cover the costs of cancer care; therefore, non-governmental organisations (NGOs) are needed to alleviate financial barriers to care. In 2002, the Children's Cancer Institute was established at the American University of Beirut Medical Center (AUBMC; Beirut, Lebanon), as a collaboration between AUBMC, St Jude Children's Research Hospital (SJCRH; Memphis, TN, USA), the Children's Cancer Center of Lebanon Foundation (CCCL; Beirut, Lebanon), and the American Lebanese Syrian Associated Charities (ALSAC; Memphis, TN, USA). This collaboration supports programmatic growth (ie, specific projects aimed at developing medical programmes and services to optimise cancer care and delivery) at the Children's Cancer Institute, and the CCCL and ALSAC ensure that no family pays out-of-pocket expenses for cancer-directed care. Between 2002 and 2012, the Children's Cancer Institute grew to provide care for 35–40% of children with cancer in Lebanon, and consultations or specialised procedures for an additional 20–25%. Networks of paediatric oncologists across the country were established, using funded disease-specific programmes, in which enrolled patients could access centralised diagnosis, specialised surgeries, radiotherapy, and unified treatment plans in coordination with their referring oncologist. Educational attainment in displaced children with cancerSupporting the health of displaced people is a challenge shared by the health system in the location to which they are displaced, non-governmental organisations, and the international community. This challenge is magnified when the host country is struggling with violence, poverty, and an unstable government. The COVID-19 pandemic has added further strain to an already difficult situation, restricting movement both within and between countries. Since 2014, the UN High Commissioner for Refugees has rolled out capacity-building projects in countries hosting displaced people, with the aim of providing access to health care for non-communicable diseases. Full-Text PDF

The Impact of Genetic Ancestry on the Biology and Prognosis of Childhood Acute Lymphoblastic Leukemia

INTRODUCTIONAcute lymphoblastic leukemia (ALL) is the most common cancer in children. Despite improvements in treatment over the past few decades, stark racial disparities persist in disease risk and cure rates. There is a paucity of data describing the genetic basis of these disparities, especially in relation to modern ALL molecular taxonomy and in the context of contemporary treatment regimens. To this end, we sought to determine the associations of genetic ancestry with ALL biology, and the relevance of genetic ancestry to survival outcomes of modern ALL therapy.METHODSThis was a multi-national genomic study of 2,428 children with ALL on front-line trials from United States (St Jude Children's Research Hospital and Children's Oncology Group), South-East Asia (Ma-Spore trials) and Latin America (Guatemala), representing diverse populations of European (EUR), African (AFR), Native American (NA), East Asian (EAS), and South Asian (SAS) descent. We performed RNA-sequencing to characterize ALL molecular subtype, and also estimated their genetic ancestral composition by comparing allele frequencies of patient and reference genomes (1000 Genomes Project reference populations). For categorization of patients into racial groups, individuals were classified based on composition of genetic ancestry as: “white” (EUR >90%), “black” (AFR >70%), “Hispanic” (NA >10% and NA greater than AFR), “East Asian” (EAS >90%), “South Asian” (SAS >70%), with the rest defined as “Other”. We then evaluated the associations of ancestry with ALL molecular subtypes and survival.RESULTSGenetic ancestral composition of the entire cohort is shown in Figure 1A. Of 21 ALL subtypes, 11 showed significant associations with ancestry. Hyperdiploid ALL was most common in white children (30.6%) and the least frequent in blacks (14.4%) (P<0.001). The frequency of ETV6-RUNX1 was highest in blacks (25.6%) and lowest in Hispanics (10.6%) (P<0.001). The DUX4 subtype was markedly more common in Asian children (14.4% of East Asians and 14.8% of South Asians) compared to black children (1.9%) (P<0.001). There was a similar trend for ZNF384 fusion, representing 6.9% of East Asians, compared to 1.7% for whites (P=0.001). TCF3-PBX1 was most prevalent in blacks at 11.9%, with the lowest at 1.7% in whites (P<0.001). PAX5 alteration frequency was highest in South Asians (11.5%) and lowest in whites (4.5%) (P=0.046). CRLF2 rearrangement occurred significantly more frequently in Hispanics (9.0%) and was least common in blacks (1.3%) (P<0.001). BCR-ABL1-like (excluding CRLF2) was also overrepresented in Hispanic children (11.4%), and occurred less frequently in East Asians (4.2%) (P<0.001). MEF2D fusion was most common in blacks (4.4%), and rare in whites (1.4%) and South Asians (0%) (P=0.013). T-ALL differed dramatically in frequency amongst races, especially between blacks and Hispanics with a 7-fold difference (26.5% vs 3.6%, P<0.001). The pattern of ALL subtype in the “Other” racial category generally mirrored that of the dominant ancestral composition, indicating a strong correlation with ancestry even within admixed populations (Figure 1B).We then examined outcomes across racial/ethnic categories. Event-free survival (EFS), overall survival (OS) and cumulative incidence of any relapse (CIR) all differed significantly across population groups (P=0.017 for EFS, P=0.05 for OS, P=0.015 for relapse). White, East Asian and South Asian children overall had more favorable outcomes compared to their black and Hispanic counterparts. Specifically, Hispanics had the poorest 5-year EFS (72.1 ± 4.2 %) and OS (82.3 ± 3.6 %), whereas South Asians had the highest EFS (94.6 ± 3.6 %) and OS (98.2 ± 2.1 %). Relapse risk trended in parallel with that of EFS and OS, with South Asians having one of the lowest CIR of 3.7 ± 2.6 %, and Hispanics having the highest at 22.8 ± 2.9 %. We repeated the analysis with genetic ancestry as a continuous variable and obtained largely similar results. Importantly, even after adjusting for biological subtypes and clinical features, Native American and African ancestries remained independently associated with poor prognosis.CONCLUSIONSALL biology and prognosis are highly associated with genetic ancestry, pointing to a genetic basis for racial disparities in ALL. Biology-driven treatment individualization is needed to eliminate racial gaps in the cure of this cancer. [Display omitted] DisclosuresEvans: Princess Máxima Center for Pediatric Oncology, Scientific Advisory Board, Chair: Membership on an entity's Board of Directors or advisory committees; BioSkryb, Inc.: Membership on an entity's Board of Directors or advisory committees; St. Jude Children's Research Hospital, Emeritus Member (began Jan 2021): Ended employment in the past 24 months. Mullighan: Illumina: Membership on an entity's Board of Directors or advisory committees; AbbVie: Research Funding; Pfizer: Research Funding; Amgen: Current equity holder in publicly-traded company. Loh: MediSix therapeutics: Membership on an entity's Board of Directors or advisory committees. Yeoh: Amgen: Honoraria, Other: Chair, Steering Committee for ALL Academy in South East Asia. Pui: Novartis: Other: Data Monitoring Committee; Adaptive Biotechnologies: Membership on an entity's Board of Directors or advisory committees.

A rare blood disorder that created a watercolour storytelling movement

Hereditary elliptocytosis; those are the two words that echoed through the room of St Jude Children's Research Hospital (Memphis, TN, USA) in the mid 80s to my parents. I was diagnosed with hereditary elliptocytosis after a few short years of genetic blood tests throughout my family. I was always an artsy child growing up—active in ballet, painting, and tap dance. My mother, who was a nurse at the time, noticed reoccurring jaundice in my eyes as well as unusual fatigue for a newborn. With a low haematocrit at just 1 month of age, my paediatrician immediately started mentioning options for a blood transfusion.

Abstract 1: Novel pediatric AML patient risk stratification by inferred protein activity through integrative network analysis and machine learning

Abstract Despite recent advances, overall survival for children with acute myeloid leukemia (AML) remains relatively low at 70 to 80%. Further refinement of risk stratification is paramount to guiding optimal therapy selection and improving outcomes. In this study, we leverage machine learning and network-based systems biology approaches that infer tumor protein activity and define key disease drivers - master regulator (MR) proteins - in pediatric AML to further refine existing patient risk stratification and identify potential therapeutic targets. Using the ARACNe and VIPER algorithms1, we reverse-engineered an AML gene regulatory network and inferred protein activity from enrichment of the proteins' transcriptional targets in gene expression signatures from a novel 1080-patient cohort treated on COG AAML1031. We integrated ensemble clustering with feed-forward feature selection on VIPER-inferred protein activity to identify groups of patients with unique protein activity signatures and correlated them to survival by Cox proportional-hazards regression analysis. We identified features predictive of each group by Monte Carlo cross-validation and binary classification. We found that the activity of 2-4 MR proteins was sufficient to predict patient stratification for each group with areas under the receiver-operator characteristic curve above 0.9. We validated our findings in three external test datasets: St-Jude Children's Research Hospital (n=249), TARGET (n=682) and Erasmus MC Sophia's Children's Hospital (n=237). We identified 10 groups with significant survival differences (P &amp;lt; 0.0001, overall survival range 42-85%). This includes a new high-risk group that is not associated with any known cytogenomic features, but shows high activity of NOTCH signaling pathway regulators HES1 and HEY2. Other groups show aberrant activity for known transcription regulators; for example RUNX1, KDM5B and POU4F1. In conclusion, we propose novel patient risk stratification based on VIPER-inferred MR protein activity in pediatric AML. We define 10 groups with differential survival, including refinement of a classically-characterized intermediate-risk cytogenomically normal group as high-risk. We classify patients into therapeutically-relevant risk groups that can guide treatment decision-making. We define the MR proteins driving these groups to offer mechanistic insights into AML tumorigenesis as well as suggest potential molecular targets for therapies. Reference: 1. Califano A, Alvarez M, The recurrent architecture of tumour initiation, progression and drug sensitivity, Nat Rev Cancer (2017), 17(2): 116-130 Citation Format: Alexandre P. Alloy, Jovana Pavisic, Rhonda E. Ries, Tanja Gruber, C Michel Zwaan, Monique L. den Boer, James R. Downing, Adolfo Ferrando, Soheil Meshinchi, Andrea Califano. Novel pediatric AML patient risk stratification by inferred protein activity through integrative network analysis and machine learning [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1.