Hematopoietic Stem Cell Transplantation Activity in Pediatric Cancer between 2008 and 2014 in the United States: A Center for International Blood and Marrow Transplant Research Report

Thyroid complications after hemopoietic stem cell transplantation in children and adolescents

PURPOSE

To evaluate the prevalence of thyroid dysfunction and its association with possible contributing factors related to diagnosis and treatment in children who received hematopoietic stem cell transplantation (HSCT) in the only national transplant unit in Greece.

METHODS

This is an observational, retrospective, single center cohort study that included 194 patients (58.6% boys) who survived for at least 1 year following allogeneic HSCT. Conditioning regimens depended upon diagnosis and protocols active at the time of transplantation. Some patients received irradiation, either central nervous system prophylaxis (n = 20), or total body irradiation (TBI) (n = 8). Thyroid gland evaluation included thyroid-stimulating hormone, free thyroxine, thyroid autoantibodies, and sonogram. Univariate and multivariate logistic models were used to examine the association of the above-mentioned factors with hypothyroidism.

RESULTS

The mean age at diagnosis and at bone marrow transplant (BMT) in years was 7.51 ± 0.46 and 7.58 ± 0.36, respectively. The median follow-up time was 4.83 years. Hypothyroidism was detected in 33 cases (17.7%), four of those patients having received TBI. Factors contributing to hypothyroidism as per the multivariate analysis were male sex, [OR: 3.005, 95% CI (1.145-7.890)], irradiation, [OR: 2.876, 95% CI (1.120-7.386)], and years after HSCT [OR: 1.148, 95% CI (1.042-1.266)], while malignancy was identified only in the univariate analysis. The multivariate model presents a good class separation capacity [AUC = 72%, 95% CI (61.4%-82.4%)], Two patients had papillary thyroid cancer, both among children who had received TBI.

CONCLUSION

These data highlight the fact that male sex and radiotherapy are two independent factors that lead to increased risk for hypothyroidism. Furthermore, the prevalence of hypothyroidism increases with time post HSCT.

Screening and interventional strategies for the late effects and toxicities of hematological malignancy treatments in pediatric survivors

INTRODUCTION

Advancements in pediatric cancer treatment have increased patient survival rates; however, childhood cancer survivors may face long-term health challenges due to treatment-related effects on organs. Regular post-treatment surveillance and early intervention are crucial for improving the survivors' quality of life and long-term health outcomes. The present paper highlights the significance of late effects in childhood cancer survivors, particularly those with hematologic malignancies, stressing the importance of a vigilant follow-up approach to ensure better overall well-being.

AREAS COVERED

This article provides an overview of the treatment history of childhood leukemia and lymphoma as well as outlines the emerging late effects of treatments. We discuss the various types of these complications and their corresponding risk factors.

EXPERT OPINION

Standardizing survivorship care in pediatric cancer aims to improve patient well-being by optimizing their health outcomes and quality of life. This involves early identification and intervention of late effects, requiring collaboration among specialists, nurses, and advocates, and emphasizing data sharing and international cooperation.

Characterizing the cutaneous late effects of allogeneic hematopoietic stem cell transplantation: A systematic review

BACKGROUND

There is a well-documented risk of secondary cutaneous malignancies following allogeneic hematopoietic stem cell transplant (HSCT), but data on risk in pediatric populations are limited. The objective of this study is to perform a systematic review of reported features and outcomes of skin cancers in pediatric allogeneic HSCT recipients.

METHODS

MEDLINE, EMBASE, CINAHL, Cochrane, and Web of Science were systematically searched (Prospero CRD42022342139). Studies reporting cutaneous cancer outcomes were included if the age at transplant was ≤19 years. Titles, abstracts, and full-text articles were screened in duplicate.

RESULTS

Out of 824 citations that were screened, 12 articles were selected for analysis. The final sample included 67 pediatric HSCT recipients, comprising 65 allogeneic transplant recipients and 2 cases of HSCT with an unknown donor type. The median age at transplant and skin cancer diagnosis were 7.4 and 13 years, respectively. Out of the 67 pediatric HSCT recipients, some patients developed more than one lesion, resulting in 71 lesions. The most common skin cancer type was cutaneous squamous cell carcinoma (32 lesions), followed by basal cell carcinoma (25 lesions). The median latency period between HSCT and skin cancer diagnosis ranged from 0 to 29 years. Identified risk factors for skin cancers included younger age at the time of transplant, exposure to total body irradiation, prolonged post-transplant immunosuppression, graft versus host disease, and sunburn.

CONCLUSION

Skin cancers are reported in pediatric allogeneic HSCT recipients, and the risk appears to be increased. More data are needed to better characterize this risk.

A peptide encoded by the circular form of the SHPRH gene induces apoptosis in neuroblastoma cells

Background

Circular RNAs (circRNAs) and their derived peptides represent largely unchartered areas in cellular biology, with many potential roles yet to be discovered. This study aimed to elucidate the role and molecular interactions of circSHPRH and its peptide derivative SHPRH-146aa in the pathogenesis of neuroblastoma (NB).

Methods

NB samples in the GSE102285 dataset were analyzed to measure circSHPRH expression, followed by in vitro experiments for validation. The role of SHPRH-146aa in NB cell proliferation, migration, and invasion was then examined, and luciferase activity assay was performed after SHPRH-146aa and RUNX1 transfection. Finally, the regulation of NB cell apoptosis by SHPRH-146aa combined with NFKBIA was tested.

Results

The GSE102285 dataset indicated overexpression of circSHPRH in NB samples, further supported by in vitro findings. Overexpression of circ-SHPRH and SHPRH-146aa inhibited proliferation, migration, and invasion of NB cells. A significant increase in apoptosis was observed, with upregulation of Caspase-3 and downregulation of Bcl-2. Furthermore, the peptide derivative SHPRH-146aa, derived from circSHPRH, suppressed NB cell malignancy traits, suggesting its role as a therapeutic target. A direct interaction between SHPRH-146aa and the transcription factor RUNX1 was identified, subsequently leading to increased NFKBIA expression. Notably, NFKBIA knockdown inhibited the pro-apoptotic effect of SHPRH-146aa on NB cells.

Conclusion

The study demonstrates that circ-SHPRH and SHPRH-146aa play significant roles in inhibiting the malignant progression of NB. They induce apoptosis primarily by modulating key apoptotic proteins Caspase-3 and Bcl-2, a process that appears to be regulated by NFKBIA. The SHPRH-146aa-RUNX1 interaction further elucidates a novel pathway in the regulation of apoptosis in NB. These findings indicate that circ-SHPRH and its derived peptide SHPRH-146aa could be potential therapeutic targets for NB treatment.

Pediatric Hematopoietic Cell Transplantation: A Longitudinal Assessment of Health-Related Quality of Life of Pediatric Donors

Pediatric donors may be at increased risk of psychological and social challenges following hematopoietic cell transplantation (HCT). Through a retrospective chart review, we evaluated the health-related quality of life (HRQL) of pediatric donors over time and examined facilitators and barriers to implementing a longitudinal psychosocial assessment. Fifty-one pediatric donors (M = 10.7 years, SD = 3.7) completed an HRQL questionnaire across six time points (T1 to T6) from prior to donation to 2 years after. Change in mean scores was assessed using a linear mixed-effect model for repeated measures design. Facilitators and barriers to implementation were examined. HRQL of pediatric donors improved between T1 and T6 with significant change in physical, emotional, and overall functioning. Facilitators to retention included the support of a clinical coordinator. Barriers to implementation included the absence of infrastructure to maintain contact with pediatric and their families. HRQL of pediatric donors of HCT improved steadily over time. Pattern of results suggests a need to further explore factors that contribute to change across time. Development of a longitudinal standardized assessment protocol that can be prospectively and feasibly implemented is integral to supporting the well-being of this group.

Small volume bone marrow aspirates with high progenitor cell concentrations maximize cell therapy dose manufacture and substantially reduce donor hemoglobin loss

BACKGROUND

Bone marrow (BM) transplantation is a life-saving therapy for hematological diseases, and the BM harbors also highly useful (progenitor) cell types for novel cell therapies manufacture. Yet, the BM collection technique is not standardized.

METHODS

Benchmarking our collection efficiency to BM collections worldwide (N = 1248), we noted a great variability of total nucleated cell (TNC) yields in BM products (HPC-M) with superior performance of our center, where we have implemented a small volume aspirate policy. Thus, we next prospectively aimed to assess the impact of BM collection technique on HPC-M quality. For each BM collection (N = 20 donors), small volume (3 mL) and large volume (10 mL) BM aspirates were sampled at 3 time points and analyzed for cell composition.

RESULTS

Compared to large volume aspirates, small volume aspirates concentrated more TNCs, immune cells, platelets, hematopoietic stem/progenitor cells, mesenchymal stromal cells (MSCs), and endothelial progenitors. Inversely, the hemoglobin concentration was higher in large volume aspirates indicating more hemoglobin loss. Manufacturing and dosing scenarios showed that small volume aspirates save up to 42% BM volume and 44% hemoglobin for HPC-M donors. Moreover, MSC production efficiency can be increased by more than 150%.

CONCLUSIONS

We propose to consider small volume BM aspiration as standard technique for BM collection.

Defibrotide modulates pulmonary endothelial cell activation and protects against lung inflammation in pre-clinical models of LPS-induced lung injury and idiopathic pneumonia syndrome

Introduction

A multiple organ dysfunction syndrome (MODS) workshop convened by the National Institute of Child Health and Human Development in 2015 identified acute respiratory distress syndrome (ARDS) and complications of allogeneic blood and marrow transplantation (allo-BMT) as contributors to MODS in pediatric patients. Pulmonary dysfunction also remains a significant complication of allo-BMT. Idiopathic pneumonia syndrome (IPS) defines non-infectious, acute, lung injury that occurs post-transplant. Injury and activation to endothelial cells (ECs) contribute to each form of lung inflammation.

Methods

Two murine models were employed. In an ARDS model, naïve B6 mice receive an intravenous (i.v.) injection of lipopolysaccharide (LPS). In the established model of IPS, naïve B6D2F1 mice receive lethal total body irradiation followed by BMT from either allogeneic (B6) or syngeneic (B6D2F1) donors. Lung inflammation was subsequently assessed in each scenario.

Results

Intravenous injection of LPS to B6 mice resulted in enhanced mRNA expression of TNFα, IL-6, Ang-2, E-, and P-selectin in whole lung homogenates. The expression of Ang-2 in this context is regulated in part by TNFα. Additionally, EC activation was associated with increased total protein and cellularity in broncho-alveolar lavage fluid (BALF). Similar findings were noted during the development of experimental IPS. We hypothesized that interventions maintaining EC integrity would reduce the severity of ARDS and IPS. Defibrotide (DF) is FDA approved for the treatment of BMT patients with sinusoidal obstruction syndrome and renal or pulmonary dysfunction. DF stabilizes activated ECs and protect them from further injury. Intravenous administration of DF before and after LPS injection significantly reduced mRNA expression of TNFα, IL6, Ang-2, E-, and P-selectin compared to controls. BALF showed decreased cellularity, reflecting less EC damage and leak. Allogeneic BMT mice were treated from day -1 through day 14 with DF intraperitoneally, and lungs were harvested at 3 weeks. Compared to controls, DF treatment reduced mRNA expression of TNFα, IL6, Ang-2, E-, and P- selectin, BALF cellularity, and lung histopathology.

Conclusion

The administration of DF modulates EC injury in models of ARDS and IPS. Cytokine inhibition in combination with agents that stabilize EC integrity may be an attractive strategy for patients in each setting.

Effect of Autograft CD34+ Dose on Outcome in Pediatric Patients Undergoing Autologous Hematopoietic Stem Cell Transplant for Central Nervous System Tumors

Consolidation with autologous hematopoietic stem cell transplantation (HSCT) has improved survival for patients with central nervous system tumors (CNSTs). The impact of the autologous graft CD34+ dose on patient outcomes is unknown. We wanted to analyze the relationship between CD34+ dose, total nucleated cell (TNC) dose, and clinical outcomes, including overall survival (OS), progression-free survival (PFS), relapse, non-relapse mortality (NRM), endothelial-injury complications (EIC), and time to neutrophil engraftment in children undergoing autologous HSCT for CNSTs. A retrospective analysis of the CIBMTR database was performed. Children aged <10 years who underwent autologous HSCT between 2008 to 2018 for an indication of CNST were included. An optimal cut point was identified for patient age, CD34+ cell dose, and TNC, using the maximum likelihood method and PFS as an endpoint. Univariable analysis for PFS, OS, and relapse was described using the Kaplan-Meier estimator. Cox models were fitted for PFS and OS outcomes. Cause-specific hazards models were fitted for relapse and NRM. One hundred fifteen patients met the inclusion criteria. A statistically significant association was identified between autograft CD34+ content and clinical outcomes. Children receiving >3.6×106/kg CD34+ cells experienced superior PFS (p = .04) and OS (p = .04) compared to children receiving ≤3.6 × 106/kg. Relapse rates were lower in patients receiving >3.6 × 106/kg CD34+ cells (p = .05). Higher CD34+ doses were not associated with increased NRM (p = .59). Stratification of CD34+ dose by quartile did not reveal any statistically significant differences between quartiles for 3-year PFS (p = .66), OS (p = .29), risk of relapse (p = .57), or EIC (p = .87). There were no significant differences in patient outcomes based on TNC, and those receiving a TNC >4.4 × 108/kg did not experience superior PFS (p = .26), superior OS (p = .14), reduced risk of relapse (p = .37), or reduced NRM (p = .25). Children with medulloblastoma had superior PFS (p < .001), OS (p = .01), and relapse rates (p = .001) compared to those with other CNS tumor types. Median time to neutrophil engraftment was 10 days versus 12 days in the highest and lowest infused CD34+ quartiles, respectively. For children undergoing autologous HSCT for CNSTs, increasing CD34+ cell dose was associated with significantly improved OS and PFS, and lower relapse rates, without increased NRM or EICs.

Review of acute kidney injury and progression to chronic kidney disease in pediatric patients undergoing hematopoietic cell transplant

While acute kidney injury (AKI) after hematopoietic cell transplant (HCT) has been well-described in pediatric patients, literature regarding the long term renal consequences of HCT-related AKI, the development of chronic kidney disease (CKD), and CKD care in pediatric patients post-HCT is limited. CKD affects almost 50% of patients after HCT with multifactorial etiology including infection, nephrotoxic medications, transplant-associated thrombotic microangiopathy, graft-versus-host disease, and sinusoidal obstruction syndrome. As renal function declines in CKD, eventually progressing to end stage kidney disease (ESKD), mortality increases and is more than 80% among patients requiring dialysis. Using society guidelines and current literature, this review summarizes definitions and etiologies of and management strategies among patients with AKI and CKD post-HCT with an emphasis on albuminuria, hypertension, nutrition, metabolic acidosis, anemia, and mineral bone disease. The goal of this review is to aid early identification and intervention in patients with renal dysfunction prior to development of ESKD, and to discuss ESKD and renal transplant in these patients post-HCT.

High-Dose Busulfan-Fludarabine Conditioning and Low Alveolar Volume as Predictors of Pulmonary Complications after Allogeneic Peripheral Blood Stem Cell Transplantation in Children

This study was conducted to investigate risk factors and predictors of infectious and noninfectious pulmonary complications (PCs) after allogeneic hematopoietic stem cell transplantation in children. We conducted a retrospective analysis of the post-transplantation PCs of 240 patients who underwent allogeneic peripheral blood stem cell transplantation (allo-PBSCT) between 2009 and 2018. Transplantation-related variables, pretransplantation baseline spirometry, body plethysmography, and CO diffusing capacity were analyzed for association with the development of infectious PCs (IPCs) and noninfectious PCs (NIPCs). Compared with the control group, the PC group had statistically significantly lower overall survival (50.6% versus 77.8%; P < .001), higher disease-related mortality (26.6% versus 54.4%; P < .001), and higher nonrelapse mortality (31.6% versus 5.9%; P < .001). A greater number of patients received pretransplantation conditioning with high-dose busulfan (520 mg/m²; Bu 520) and fludarabine (160 mg/m²; Flu 160) in both the IPC and NIPC groups. In the multivariate Cox hazard regression analysis, Bu 520 significantly increased the risk of NIPCs (hazard ratio [HR], 1.99; 95% confidence interval [CI], 1.13 to 3.49; P = .016), and Flu 160 was a predictor of IPCs (HR, 1.99; 95% CI, 1.13 to 3.49; P = .016). The Bu 520 + Flu 160 regimen was associated with a statistically significant increase in the risk of NIPC (HR, 1.92; 95% CI, 1.09 to 3.37; P = .023). In a multivariate analysis using pretransplantation baseline lung function, alveolar volume (VA) grades 3 and 4 and lung function score (LFS) VA categories III and IV were associated with increased risk for both IPCs and NIPCs. Our data identify receipt of the high-dose Bu-Flu conditioning regimen as an independent risk factor for NIPCs after allo-PBSCT. Impaired CO diffusing capacity before transplantation, especially VA reduction, contributes to the risk of post-transplantation pulmonary complications, and pretransplantation risk can be estimated by grading the degree of insufficiency of VA and LFS VA.

Metabolic Dysregulation in Adult Survivors of Pediatric Hematopoietic Stem Cell Transplantation: The Role of Incretins

CONTEXT

Survivors of pediatric hematopoietic stem cell transplantation (HSCT) have increased risk of developing metabolic syndrome (MetS), but the mechanisms are poorly understood.

OBJECTIVE

We aimed to test the hypothesis that insufficient secretion of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) plays a pathogenetic role in HSCT survivors with MetS.

METHODS

This cross-sectional cohort study, conducted at the Danish national referral center for HSCT, studied 42 male HSCT survivors (median age 28.9 years) for a median 21.2 years from HSCT, along with 15 age- and sex-matched healthy controls. Main outcome measures were glucose metabolism and incretin hormones (by oral glucose tolerance test [OGTT]) and MetS criteria. The hypothesis was formulated before data collection.

RESULTS

GLP-1, GIP, and glucagon during an OGTT were similar in patients and controls, with no overall difference between survivors with (24%) and without MetS. However, fasting glucagon was significantly higher in patients with hypertriglyceridemia (mean difference [MD]: 6.1 pmol/L; 95% CI, 1.5-10.8; P = 0.01), and correlated with HDL (MD: 4.7 mmol/L; 95% CI, -0.6 to 9.9; P = 0.08), android-gynoid ratio (correlation coefficient [r] = 0.6, P = 0.0001) and waist-hip ratio (r = 0.5, P = 0.002). A similar pattern was seen for GIP, correlating positively with triglyceride (MD: 60%; 95% CI, 44-82; P = 0.002). GIP levels were significantly increased in patients treated with total body irradiation (TBI) (MD: 165%; 95% CI, 118-230; P = 0.004), which was found to be a significant risk factor for MetS.

CONCLUSION

This study demonstrates an altered production of incretin hormones in HSCT survivors previously treated with TBI, developing dyslipidemia and abdominal adiposity.

Outcomes of blood and marrow transplantation in children less than 2-years of age: 23 years of experience at a single center

Objectives

Allogeneic hematopoietic cell transplantation (Allo-HCT) is a curative option for children with various malignant and non-malignant diseases. Most reports studied all age groups amongst children. Herein we analyzed our data in children transplanted at or less than 2-years of age.

Patients and methods

We reviewed medical charts of 618 patients who underwent 666 transplantation at our center between 1993 and 2015. There were 340 boys and 278 girls. Median age was 0.7 years (range 0.04-2). Stem cell source was bone marrow (BM) in 492 (73.9%), unrelated umbilical cord blood (UCB) in 161 (24.2%) followed by peripheral blood stem cell (PBSC) in 13 (2%) patients. Matched siblings were the most common donors (n = 356, 53.5%), followed by unrelated (n = 161, 24.2%) with haploidentical family member donors in 29 (4.4%) transplants. Disease groups were categorized as benign hematology (Thalassemia, Fanconi, Aplastic anemia etc.), benign neoplasm (Langerhans cell histiocytosis, Hemophagocytic Lymphohistiocytosis etc.), non-neoplasms (metabolic disorders, immunodeficiency disorders etc.) and Leukemia/lymphomas (myeloid and lymphoid malignancies etc.).

Results

Cumulative incidence of acute GvHD (I-IV) was 31.5% (n = 210) and grade III-IV GvHD was 8.7% (n = 58). At median follow-up of 115.1 months, the cumulative probability of overall survival (OS) at 5 years was 70.0% ± 1.9%. Our mortality rate was 31.2% (n = 193). The five-year OS was significantly better in patients transplanted for benign hematological disorders (P = .001). Patients transplanted using BM/PBSC as source of stem cells fared significantly better compared to those in which CB was used (P<.001). Post-transplant graft failure remains the leading cause requiring further transplants in this age group. In conclusion, the cumulative probability of OS at 5 years was about 70.0% for all with an OS of 61% in our haploidentical recipients.

Conclusion

Analyzing our institutional data over time has enabled us to develop tentative strategies to minimize transplant related toxicities in very young children who are candidates for allo-HCT.

A Prolonged Outbreak of Human Adenovirus A31 (HAdV-A31) Infection on a Pediatric Hematopoietic Stem Cell Transplantation Ward with Whole Genome Sequencing Evidence of International Linkages

A surge in hematopoietic stem cell transplantation (HSCT) human adenovirus A31 (HAdV-A31) infections was initially observed in late 2014/2015 at SickKids (SK) Hospital, Toronto, Canada. In response, enhanced laboratory monitoring for all adenovirus infections was conducted. Positive samples underwent genotyping, viral culture, and, in selected cases, whole-genome sequencing (WGS). HAdV-A31 specimens/DNA obtained from four international pediatric HSCT centers also underwent WGS. During the SK outbreak period (27 October 2014 to 31 October 2018), 17/20 HAdV-A31 isolates formed a distinct clade with 0 to 8 mutations between the closest neighbors. Surveillance before and after the outbreak detected six additional HAdV-A31 HSCT cases; three of the four sequenced cases clustered within the outbreak clade. Two SK outbreak isolates were identical to sequences from two patients in an outbreak in England. Three SK non-outbreak sequences also had high sequence similarity to strains from three international centers. Environmental PCR testing of the HSCT ward showed significant adenovirus contamination. Despite intense infection control efforts, we observed re-occurrence of infection with the outbreak strain. Severe but nonfatal infection was observed more commonly with HAdV-A31 compared to other genotypes, except HAdV-C1. Our findings strongly implicate nosocomial spread of HAdV-A31 over 10 years on a HSCT unit and demonstrate the value of WGS in defining and mapping the outbreak. Close linkages among strains in different countries suggest international dissemination, though the mechanism is undetermined. This large, extended outbreak emphasizes the pre-eminent role of HAdV-A31 in causing intractable pediatric HSCT outbreaks of severe illness worldwide.

Fluid Overload in Pediatric Acute Respiratory Distress Syndrome after Allogeneic Hematopoietic Cell Transplantation

The aim of the study is to examine the relationship between fluid overload (FO) and severity of respiratory dysfunction in children post-hematopoietic cell transplantation (HCT) with pediatric acute respiratory distress syndrome (PARDS). This investigation was a secondary analysis of a multicenter retrospective cohort of children (1month to 21 years) post-allogeneic HCT with PARDS receiving invasive mechanical ventilation (IMV) from 2009 to 2014. Daily FO % (FO%) and daily oxygenation index (OI) were calculated for each patient up to the first week of IMV (day 0 = intubation). Linear mixed-effect regression was employed to examine whether FO% and OI were associated on any day during the study period. In total, 158 patients were included. Severe PARDS represented 63% of the cohort and had higher mortality (78 vs. 42%, p <0.001), fewer ventilator free days at 28 (0 [IQR 0–0] vs. 14 [IQR 0–23], p <0.001), and 60 days (0 [IQR 0–27] v. 45 [IQR 0–55], p <0.001) relative to non-severe PARDS. Increasing FO% was strongly associated with higher OI (p <0.001). For children with 10% FO, OI was higher by nearly 5 points (adjusted β 4.6, 95% CI [2.9, 6.3]). In subgroup analyses, the association between FO% and OI was strongest among severe PARDS (p <0.001) and during the first 3 days elapsed from intubation (p <0.001). FO% was associated with lower PaO2/FiO2 (adjusted β −1.92, 95% CI [−3.11, −0.73], p = 0.002), but not mean airway pressure (p = 0.746). In a multicenter cohort of children post-HCT with PARDS, FO was independently associated with oxygenation impairment. The associations were strongest among children with severe PARDS and early in the course of IMV.

T-Cell Depleted Haploidentical Transplantation in Children With Hematological Malignancies: A Comparison Between CD3+/CD19+ and TCRαβ+/CD19+ Depletion Platforms

Background

T-cell depleted (TCD) haploidentical transplantation using CD3+/CD19+ and TCRαβ+/CD19+ depletion techniques has been increasingly used in children with hematological malignancies. We present a retrospective study aimed to compare transplant outcomes in children with leukemia receiving a TCD haploidentical transplant using either CD3+/CD19+ or TCRαβ+/CD19+ platforms.

Methods

A total of 159 children with leukemia (ALL=80) (AML=79) that received a TCD haploidentical transplantation using either CD3+/CD19+ (n=79) or TCRαβ+/CD19+ (n=80) platforms between 2005 and 2020 were included. Median age was 9 years in both groups. There were no differences in patient, donor, and transplant characteristics between groups except for donor KIR B genotype more frequent in the TCRαβ+/CD19+ group (91%) than in the CD3+/CD19+ group (76%) (p=0.009) and a high number of NK+ cells and lower CD19+ cells infused in the TCRαβ+/CD19+ group (35.32x106/kg and 0.06 x106/Kg) than in the CD3+/CD19 group (24.6x106/Kg and 0.25 x106/Kg) (p=0.04 and p=0.0001), respectively. Conditioning was based on TBF. Median follow-up for survivors was 11 years (range; 8-16 y) in CD3+/CD19+ group and 5 years (range; 2-9 y) in the TCRαβ+/CD19+ group.

Results

Engraftment kinetics were similar in both groups (13 days for neutrophils and 10 days for platelets). There was no difference in the incidence of acute GvHD II-IV (29 ± 5% in the CD3+/CD19+ group vs 38 ± 5% in the TCRαβ+/CD19+ group) and chronic GvHD (32 ± 5% vs 23 ± 4%, respectively). NRM was 23 ± 5% in the CD3+/CD19+group vs 21 ± 4% in the TCRαβ+/CD19+group. Relapse incidence was also similar, 32 ± 5% vs 34 ± 6%, respectively. DFS and OS were not different (45 ± 5% vs 45 ± 6% and 53 ± 6% vs 58 ± 6% respectively). As there were no differences on transplant outcomes between groups, we further analyzed all patients together for risk factors associated with transplant outcomes. On multivariate analysis, we identified that early disease status at transplant (HR: 0.16; 95%CI (0.07-0.35) (p=0.0001), presence of cGvHD (HR: 0.38; 95%CI (0.20-0.70) (p= 0.002), and donor KIR-B genotype (HR: 0.50; 95%CI (0.32-0.90) (p=0.04) were associated with better DFS.

Conclusions

Our data suggest that there are no advantages in transplant outcomes between TCD platforms. Risk factors for survival are dependent on disease characteristic, donor KIR genotype, and chronic GvHD rather than the TCD platform used.

Gut Microbiome Suffers from Hematopoietic Stem Cell Transplantation in Childhood and Its Characteristics Are Positively Associated with Intra-Hospital Physical Exercise

Gut microbiome impairment is a serious side effect of cancer treatment. The aim of this study was to identify the effects of hematopoietic stem cell transplantation (HSCT) treatment on gut microbiota composition in children with acute lymphoblastic leukemia (ALL). Fecal microbiotas were categorized using specific primers targeting the V1-V3 region of 16S rDNA in eligible pediatric ALL patients after HSCT (n = 16) and in healthy controls (Ctrl, n = 13). An intra-hospital exercise program was also organized for child patients during HSCT treatment. Significant differences in gut microbiota composition were observed between ALL HSCT and Ctrl with further negative effects. Plasma C-reactive protein correlated positively with the pathogenic bacteria Enterococcus spp. and negatively with beneficial bacteria Butyriccocus spp. or Akkermansia spp., respectively (rs = 0.511, p = 0.05; rs = -0.541, p = 0.04; rs = -0.738, p = 0.02). Bacterial alpha diversity correlated with the exercise training characteristics. Therefore, specific changes in the microbiota of children were associated with systemic inflammation or the ability to exercise physically during HSCT treatment.

The influence of contextual factors on children's communication of pain during pediatric Haematopoietic Stem Cell Transplantation: A qualitative case study

PURPOSE

The aim of this study was to describe how contextual factors related to the clinical setting of a pediatric HSCT unit influenced children's communication of pain to their health-care providers and parents during hospitalization.

DESIGN AND METHODS

A qualitative case study design was conducted in two-phases in a tertiary level pediatric HSCT unit. The Social Communication Model of Pain provided the conceptual framework for the study. In phase one participants were parents and phase two participants were health-care providers and children in a pediatric HSCT unit. Parents participated in semi-structured interviews at 30- and 90-days post-transplantation regarding their child's communication of pain. Naturalistic observations of children receiving clinical care were conducted and health-care providers participated in semi-structured interviews.

RESULTS

Children extensively denied pain to their parents and health-care providers. When children did communicate pain, they were motivated by a need to seek interventions for their pain. Children's willingness to communicate pain was influenced by the physiological impact of HSCT therapy, their previous experiences of pain, their relationship with parents and health-care providers and parents and an environment of fear and uncertainty.

CONCLUSIONS

There is a pressing need for child-centric approaches to support children to communicate their pain experiences to overcome the limitations imposed by the complexity of their medical treatment and the clinical environment in which they receive healthcare.

PRACTICE IMPLICATIONS

In the context of HSCT therapy children may not communicate pain until pain is severe, and no longer bearable, or outright deny the presence of pain.

Time to initiation of pre-emptive therapy for cytomegalovirus impacts overall survival in pediatric hematopoietic stem cell transplant recipients

BACKGROUND AIMS

Cytomegalovirus (CMV) reactivation is a significant complication following allogeneic hematopoietic stem cell transplant (HSCT) and affects upwards of 40% of pediatric HSCT patients. Pre-emptive therapy remains the only effective treatment strategy available for pediatric patients following CMV reactivation. Little is known about how the timing of induction treatment following CMV reactivation impacts outcomes in pediatric patients, especially following ex vivo T-cell-depleted (TCD) HSCT.

METHODS

The authors evaluated how the timing of induction treatment after CMV reactivation impacts overall survival (OS) and CMV disease in pediatric patients undergoing TCD HSCT at a single institution. The authors retrospectively analyzed patients treated on the pediatric service who received an initial ex vivo TCD HSCT at Memorial Sloan Kettering Cancer Center (MSKCC) from January 2010 to June 2018. CMV reactivation was defined as ≥1 CMV polymerase chain reaction >500 copies/mL in whole blood or >137 IU/mL in plasma within the first 180 days after allogeneic HSCT. To analyze the impact of the timing of induction treatment, the authors' primary study outcome was OS and secondary outcome was CMV disease.

RESULTS

A total of 169 patients who underwent an initial allogeneic TCD HSCT on the pediatric service at MSKCC from January 2010 to June 2018 were included in the analysis. Thirty-seven (22%) patients reactivated CMV during the first 180 days following HSCT. Of those patients who reactivated CMV, CMV donor/recipient (D/R) serostatus was as follows: D+/R+ n = 28 (76%) and D-/R+ n = 9 (24%). There was no CMV reactivation observed among recipients who were CMV-seronegative irrespective of donor serostatus. In those patients who reactivated CMV, the median time from HSCT to CMV reactivation was 24 days (interquartile range, 20-31). Eleven patients ultimately developed CMV disease in addition to CMV viremia, whereas the remaining patients had only CMV viremia. The cumulative incidence of CMV reactivation at 60 days was 45.2% (95% confidence interval [CI], 32.8-57.5) in the D+/R+ subgroup and 31% (95% CI, 14.2-47.9) in the D-/R+ subgroup. For those patients who reactivated CMV, 30 (81%) received induction treatment with ganciclovir or foscarnet. To analyze the impact of the timing of induction treatment on clinical outcomes, the authors restricted the analysis to those patients who reactivated CMV and received induction treatment (n = 30). The timing of induction treatment was significantly associated with OS, with optimal timing of initiation within a week of CMV reactivation (P = 0.02). There was no significant impact on the timing of induction treatment and risk of CMV disease (P = 0.30).

CONCLUSIONS

In ex vivo TCD HSCT in pediatric patients, early initiation of induction treatment after CMV reactivation is associated with improved OS.

The Effect of Educational Intervention on Care Dependency and Symptom Management After Hematopoietic Stem Cell Transplantation: A Theory-Based Randomized Controlled Study

The objective of the research was to determine the effect of educational intervention based on Bandura’s Social Cognitive Learning Theory on care dependency and symptom management after hematopoietic stem cell transplantation. Methods. This randomized controlled trial was conducted between January 2019 and February 2020 at the Hematopoietic Stem Cell Transplantation Center. All the patients were randomly divided into two groups: 53 individuals in the intervention group and 53 individuals in the control group. The sociodemographic data collection form, the Edmonton Symptom Assessment Scale and the Care Dependency Scale were used for data collection. Data were collected from the patients one day after hematopoietic stem cell transplantation and 12 weeks later. Results. There were no statistically significant differences between the groups regarding the mean scores of the Edmonton Symptom Assessment Scale and the Care Dependency Scale at baseline. Twelve weeks after intervention, there were statistically significant differences between the groups regarding the mean scores of the Edmonton Symptom Assessment Scale and the Care Dependency Scale. Conclusions. Educational intervention along with telephone counseling based on Bandura’s theory was found to be an effective way to reduce symptom severity and care dependency in patients who underwent hematopoietic stem cell transplantation and is recommended for all patients after hematopoietic stem cell transplantation.

Ethical and Analytic Challenges With Genomic Sequencing of Relapsed Hematologic Malignancies Following Allogeneic Hematopoietic Stem-Cell Transplantation

The implementation of precision medicine and next-generation sequencing technologies in the field of oncology is a novel approach being more widely studied and used in cases of high-risk primary and recurrent malignancies. Leukemias are the second most common cause of cancer-related mortality in children and the sixth most in adults. Relapsed leukemia represents a major component of the population that may benefit from genomic sequencing. However, ethical and analytic challenges arise when considering sequencing of biologic samples obtained from patients with relapsed leukemia following allogeneic hematopoietic stem-cell transplantation. Blood from the recipient after transplantation would include donor-derived cells and thus, genomic sequencing of recipient blood will interrogate the donor germline in addition to the somatic genetic profile of the leukemia cells and the recipient germline. This is a situation for which the donor will not have typically provided consent and may be particularly problematic if actionable secondary or incidental findings related to the donor are uncovered. We present the challenges raised in this scenario and provide strategies to mitigate this risk.

Non-inferiority of fragmented care for high-risk pediatric neuroblastoma patients: a single institution analysis

Pediatric neuroblastoma (NB) patients receive multi-modal therapy and may experience care fragmented among multiple institutions with a significant travel burden, which has been associated with poor outcomes for some adult cancers. We hypothesized that fragmented care for pediatric NB patients is associated with inferior outcomes compared to treatment consolidated at one location. We reviewed paper and electronic records for pediatric NB patients who received ≥1 hematopoietic stem cell transplant (HSCT) at Duke from 1990-2017. Fragmented care was defined by treatment at >1 institution and grouped by 2 institutions vs. 3+ institutions. Distances were calculated using Google Maps. To compare all care groups, we used Fisher's Exact and Kruskal-Wallis tests for demographic and treatment characteristics, Kaplan-Meier for unadjusted overall survival (OS), and Cox proportional hazards for factors associated with OS. Of 127 eligible patients, 102 (80.3%) patients experienced fragmented care, with 17 treated at 3+ facilities. Kaplan-Meier analysis did not associate fragmented care with increased mortality (log-rank p = 0.13). With multivariate analysis, only earlier diagnostic decade and greater distance to HSCT remained significantly associated with worsened OS. In this single institutional study, we found fragmented care did not impact overall survival. Worsened overall survival was associated with increased travel distance for HSCT and further research should aim to improve supportive processes for patients undergoing HSCT for high-risk neuroblastoma.

Impact of mother donor, peripheral blood stem cells and measurable residual disease on outcomes after haploidentical hematopoietic cell transplantation with post-transplant cyclophosphamide in children with acute leukaemia

Haploidentical hematopoietic-cell transplantation using post-transplant cyclophosphamide(Haplo-PTCy) is a feasible procedure in children with haematologic malignancies. However, data of a large series of children with acute leukaemia(AL) in this setting is missing. We analysed 144 AL Haplo-PTCy paediatric recipients; median age was 10 years. Patients had acute lymphoblastic(ALL; n = 86) or myeloblastic leukaemia(AML; n = 58) and were transplanted in remission(CR1: n = 40; CR2: n = 57; CR3+: n = 27) or relapse (n = 20). Bone marrow was the graft source in 57%; donors were father (54%), mother (35%), or sibling (11%). Myeloablative conditioning was used in 87%. Median follow-up was 31 months. At day +100, cumulative incidence (CI) of neutrophil recovery and acute GVHD (II-IV) were 94% and 40%, respectively. At 2-years, CI of chronic GVHD and relapse, were 31%, 40%, and estimated 2-year overall survival (OS), leukaemia-free survival (LFS) and graft-versus-host-relapse-free survival (GRFS) were 52%, 44% and 34% respectively. For patients transplanted in remission, positive measurable residual disease (MRD) prior to transplant was associated with decreased LFS (p = 0.05) and GRFS (p = 0.003) and increased risk of relapse (p = 0.02). Mother donor was associated with increased risk of chronic GVHD (p = 0.001), decreased OS (p = 0.03) and GRFS (p = 0.004). Use of PBSC was associated with increased risk of chronic GVHD (p = 0.04). In conclusion, achieving MRD negativity pre-transplant, avoiding use of mother donors and PBSC as graft source may improve outcomes of Haplo-PTCy in children with AL.

Pulmonary Complications of Pediatric Hematopoietic Cell Transplantation. A National Institutes of Health Workshop Summary

Approximately 2,500 pediatric hematopoietic cell transplants (HCTs), most of which are allogeneic, are performed annually in the United States for life-threatening malignant and nonmalignant conditions. Although HCT is undertaken with curative intent, post-HCT complications limit successful outcomes, with pulmonary dysfunction representing the leading cause of nonrelapse mortality. To better understand, predict, prevent, and/or treat pulmonary complications after HCT, a multidisciplinary group of 33 experts met in a 2-day National Institutes of Health Workshop to identify knowledge gaps and research strategies most likely to improve outcomes. This summary of Workshop deliberations outlines the consensus focus areas for future research.

Pediatric HCT in Florida (2014 -2016): A report from the FPBCC

FPBCC was formed in 2018 by five pediatric transplant programs in Florida. One of the key objectives of the consortium is to provide outcome analyses by combining HCT data from all the participating centers in order to identify areas for improvement. In this first FPBCC landscape report we describe the patient and transplant characteristics of pediatric patients undergoing first allo and auto HCT between 2014 and 2016 in Florida. The source of data was eDBtC of the CIBMTR. Over the span of 3 years, a total of 230 pediatric patients underwent allo-HCT and 104 underwent auto-HCT at the participating centers. The most significant predictor of survival in allo-HCT recipients with malignant disorders was the degree of HLA- match, while in the recipients of allo-HCT with non-malignant disorders the predictors of survival included age, donor relationship and degree of HLA match. Our analyses identified the need to improve reporting of primary cause of death and improve on donor selection process given that the degree of HLA match remains the most important predictor of survival. This first FPBCC-wide review describes the trends in pediatric HCT activity between 2014 and 2016 among the participating centers in Florida and confirms feasibility of using eDBtC data platform and collaborative approach in order to identify areas for improvement in outcomes.

Association of persistent tachycardia with early myocardial dysfunction in children undergoing allogeneic hematopoietic cell transplantation

Cancer survivors who have undergone hematopoietic cell transplantation (HCT) are at risk for myocardial dysfunction. Children who receive allogenic HCT encounter systemic inflammation resulting in tachycardia and hypertension. The effect of these abnormalities on myocardial function is not known. The aim of this study was to determine whether cardiac dysfunction early after HCT can be predicted by tachycardia or hypertension, within a retrospective single-center sample of pediatric HCT recipients. Early tachycardia or hypertension was defined as a majority of values taken from infusion date to 90 days post-infusion being abnormal. Ejection fraction <53% determined systolic dysfunction. A composite score of accepted pediatric diastolic abnormalities determined diastolic dysfunction. Among 80 subjects (median age 8 years), early tachycardia, systolic dysfunction, and diastolic dysfunction were present in 64%, 25%, and 48% of the sample, respectively. In multivariable models, early tachycardia was an independent predictor of early systolic dysfunction (OR = 12.6 [1.4-112.8], p = 0.024) and diastolic dysfunction (OR = 3.9 [1.3-11.5], p = 0.013). Tachycardia and cardiac dysfunction are common and associated with one another in the early period after pediatric HCT. Future studies may elucidate the role of tachycardia and myocardial dysfunction early after HCT as important predictors of future cardiovascular dysfunction.

Cardiovascular disease and its management in children and adults undergoing hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for many malignancies, hemoglobinopathies, metabolic diseases, bone marrow failure syndromes, and primary immune deficiencies. Despite the significant improvement in survival afforded by HSCT, the therapy is associated with major short and long-term morbidity and mortality. Cardiovascular complications such as cardiomyopathy, arrhythmias, pulmonary hypertension, and pericardial effusions are increasingly recognized as potential outcomes following HSCT. The incidence of cardiac complications is related to various factors such as age, co-morbid medical conditions, whether patients received cardiotoxic chemotherapy prior to HSCT, the type of HSCT (autologous versus allogeneic), and the specific conditioning regimen. Thus, the cardiovascular evaluation has become a core component of the pre-transplant assessment, however, the practice differs from center to center as national guidelines and contemporary high-quality studies are lacking. We review the incidence of cardiotoxicity in pediatric and adult HSCT, potential mechanisms of injury, and effects on long-term outcomes. We also discuss the possible therapeutic approaches when disease arises, as well as the indications and need for surveillance before, during, and after transplantation.

Economic burden of acute steroid-refractory graft-versus-host disease in commercially insured pediatric patients

BACKGROUND: Acute graft-versus-host disease (aGVHD), a potentially life-threatening complication of hematopoietic stem cell transplantation (HSCT), often occurs within 100 days of HSCT. While steroids are typically used as first-line treatment, there is no consensus on second-line steroid-refractory (SR) treatments. SR aGVHD is associated with significantly worse pediatric health outcomes, but less is known about its economic impact. OBJECTIVE: To evaluate the economic burden of SR pediatric aGVHD in a commercially insured US patient population. METHODS: Retrospective analyses were conducted using medical and pharmacy claims data from the HealthCore Integrated Research Database (study period January 1, 2006-May 31, 2019). Included patients had at least 1 claim for allogeneic HSCT (earliest HSCT claim set as index date), no claims for autologous HSCT, and no pre-index GVHD. Patients were aged less than 18 years with no minimum pre- or post-index continuous enrollment. The GVHD cohort included patients with at least 1 claim for aGVHD over 100 days from index with at least 1 claim for any steroid and at least 1 claim for second-line therapy, both on or after the date of the first aGVHD claim. Patients post-HSCT with no GVHD claims over follow-up formed the comparison cohort. Health care resource utilization and costs over 12 months from the index date were calculated and compared between cohorts using parametric testing. RESULTS: 38 patients with SR aGVHD and 184 controls were included. Mean age and sex were similar for aGVHD (8.6 years, 50% female) and control (8.2 years, 45% female). During the 12-month post-index follow-up, SR aGVHD patients had higher rates of complications vs controls (* for P < 0.05): anemia (79% vs 68%), drug-induced anemia* (53% vs 34%), neutropenia (63% vs 53%), thrombocytopenia (58% vs 42%), gastrointestinal complications* (95% vs 65%), and infections* (95% vs 79%). Mean inpatient length of stay was longer by 31.6 days (P < 0.01) with a total average of 96.0 days for those with SR aGVHD vs 64.3 days for the controls. More SR aGVHD patients required inpatient total parenteral nutrition (71% vs 58%), readmission within 12 months of discharge from index hospitalization* (89% vs 60%), ER visits (34% vs 24%), and outpatient visits (100% vs 86%). Total 12-month mean medical costs were higher in aGVHD patients: $1,212,944 vs $673,491 (P < 0.001), mostly because of complication-related costs: $868,966 vs $396,757 (P < 0.001). Among patients with SR aGVHD, mean total costs were higher by about $1.8 million ($2,609,445 vs $812,385; P = 0.014) for those who died compared with those who were alive within 12 months. CONCLUSIONS: SR aGVHD in pediatric patients following HSCT is associated with incremental 12-month medical costs of greater than $500,000, driven largely by complications. DISCLOSURES: This research was sponsored by Mesoblast, Inc. Grabner is an employee of HealthCore, Inc., which acted as consultants to Mesoblast, Inc., during the conduct of this research. Strati is an employee of Mesoblast, Inc. Sandman and Forsythe are employees of Purple Squirrel Economics, which acted as consultants to Mesoblast, Inc., during the conduct of this research. This work was presented at the AMCP Annual Meeting online in April 2020 and was an encore presentation at AMCP Nexus 2020 Virtual in October 2020.

Length of Stay and Health Care Utilization Among Pediatric Autologous Hematopoietic Cell Transplantation Recipients

Autologous hematopoietic cell transplantation (autoHCT) has become a critical component in the treatment of pediatric malignancies, allowing for high-dose chemotherapy to be given safely and with greater efficacy in a subset of children at high risk for relapse. Risk factors associated with hospital length of stay (LOS) in adults undergoing autoHCT have been studied extensively; however, there is a paucity of studies describing risk factors associated with LOS and health care cost in children undergoing autoHCT. This study sought to identify factors influencing LOS and cost in pediatric autoHCT. We assessed LOS from autologous stem cell infusion from day 0 (D0) in 100 autoHCT admissions in 73 patients with malignant disease between 2007 and 2019. We evaluated demographic, pre-transplantation, post-transplantation, and socioeconomic variables to identify potential risk factors associated with LOS and cost. AutoHCT cost data were provided by the Pediatric Health Information System database. Indications for autoHCT included neuroblastoma (35.6%), brain tumor (27.4%), and relapsed lymphoma (24.7%). The median patient age was 4.88 years (range, 0.72 to 22 years), with 71% age <12 years, and the cohort was 63% male, 77% white, and 41% Hispanic. The median LOS from D0 was 19 days (range, 13 to 100 days). On multivariable analysis, age >12 years compared with 2 to 12 years (estimate, -8.9 days; 95% confidence interval [CI], -15.1 to -2.8; P = .004) and complete remission/very good partial response disease status (estimate, -5.0 days; 95% CI, -9.6 to -0.4 days; P = .031) were associated with a significantly decreased median LOS, whereas Hispanic ethnicity (estimate, +6.8 days; 95% CI, 1.1 to 12.6 days; P = .019), >5 days of fever (estimate, +7.3 days; 95% CI, 1.4 to 13.2 days; P = .015), and pediatric intensive care unit (PICU) LOS (estimate, +14.9 days; 95% CI, 1.8 to 28.0 days; P = .025) were associated with a significant increase in median LOS. The median cost per transplantation admission was $96,850 (range, $39,833 to $587,321). Multivariable analysis showed that age >12 years (estimate, -$6,776; 95% CI, -$71,787 to -$11,402; P = .007) or <2 years (estimate, -$32,426; 95% CI, -$53,507 to -$11,345; P = .003), and complete remission/very good partial response disease status (estimate, -$20,266; 95% CI, -$40,211 to -$322; P = .046) were associated with significantly decreased median cost, whereas >5 days of fever (estimate, +$58,886; 95% CI, $30,667 to $87,105; P < .001) and PICU admission (estimate, +$102,458; 95% CI, $23,843 to $181,076; P = .011) were associated with significantly increased median cost. In summary, fever and PICU stay were found to be risk factors for increased LOS and cost. Age <12 years and Hispanic ethnicity were risk factors for increased LOS, whereas age <2 years and >12 years and female sex were associated with decreased cost. Further investigation to determine specific factors influencing LOS and cost is warranted to identify potentially modifiable risks within these patient populations.

Long-Term Follow-Up of CD19-CAR T-Cell Therapy in Children and Young Adults With B-ALL

PURPOSE

CD19 chimeric antigen receptor (CD19-CAR) T cells induce high response rates in children and young adults (CAYAs) with B-cell acute lymphoblastic leukemia (B-ALL), but relapse rates are high. The role for allogeneic hematopoietic stem-cell transplant (alloHSCT) following CD19-CAR T-cell therapy to improve long-term outcomes in CAYAs has not been examined.

METHODS

We conducted a phase I trial of autologous CD19.28ζ-CAR T cells in CAYAs with relapsed or refractory B-ALL. Response and long-term clinical outcomes were assessed in relation to disease and treatment variables.

RESULTS

Fifty CAYAs with B-ALL were treated (median age, 13.5 years; range, 4.3-30.4). Thirty-one (62.0%) patients achieved a complete remission (CR), 28 (90.3%) of whom were minimal residual disease-negative by flow cytometry. Utilization of fludarabine/cyclophosphamide-based lymphodepletion was associated with improved CR rates (29/42, 69%) compared with non-fludarabine/cyclophosphamide-based lymphodepletion (2/8, 25%; P = .041). With median follow-up of 4.8 years, median overall survival was 10.5 months (95% CI, 6.3 to 29.2 months). Twenty-one of 28 (75.0%) patients achieving a minimal residual disease-negative CR proceeded to alloHSCT. For those proceeding to alloHSCT, median overall survival was 70.2 months (95% CI, 10.4 months to not estimable). The cumulative incidence of relapse after alloHSCT was 9.5% (95% CI, 1.5 to 26.8) at 24 months; 5-year EFS following alloHSCT was 61.9% (95% CI, 38.1 to 78.8).

CONCLUSION

We provide the longest follow-up in CAYAs with B-ALL after CD19-CAR T-cell therapy reported to date and demonstrate that sequential therapy with CD19.28ζ-CAR T cells followed by alloHSCT can mediate durable disease control in a sizable fraction of CAYAs with relapsed or refractory B-ALL (ClinicalTrials.gov identifier: NCT01593696).

G-CSF treatment of healthy pediatric donors affects their hematopoietic microenvironment through changes in bone marrow plasma cytokines and stromal cells

Although G-CSF mobilized peripheral blood stem cell (PBSC) transplantation is commonly used in adults, bone marrow (BM) is still the preferred stem cell source in pediatric stem cell transplantation. Despite the fact that G-CSF is increasingly being used to enhance the hematopoietic stem/progenitor cell (HSPC) yield in BM transplantation (G-BM), the direct effects of G-CSF on the pediatric BM microenvironment have never been investigated. The BM hematopoietic niche provides the physical space where the HSPCs reside. This BM niche regulates HSPC quiescence and proliferation through direct interactions with other niche cells, including Mesenchymal Stromal Cells (MSCs). These cells have been shown to secrete a wide range of hematopoietic cytokines (CKs) and growth factors (GFs) involved in differentiation, retention and homing of hematopoietic cells. Here, we assessed changes in the BM microenvironment by measuring levels of 48 different CKs and GFs in G-BM and control BM (C-BM) plasma from pediatric donors. In addition, the effect of G-CSF on cell numbers and characteristics of HSPCs and MSCs was assessed. IL-16, SCGF-b, MIP-1b (all >1000 pg/mL) and RANTES (>10.000 pg/mL) were highly expressed in healthy donor pediatric BM plasma. Levels of IL-3, IL-18, GROa, MCP-3 (p<0.05) were increased in G-BM, whereas levels of RANTES (p<0.001) decreased after G-CSF treatment. We found a negative correlation with increasing age for IL2-Ra and LIF (p<0.05). In addition, a concomitant increase in the number of both hematopoietic and fibroblast colony forming units was observed, indicating that G-CSF affects both HSPC and MSC numbers. In conclusion, G-CSF treatment of healthy pediatric donors affects the hematopoietic BM microenvironment by expansion of HSPC and MSC numbers and modifying local CK and GF levels.

The influence of stem cell source on transplant outcomes for pediatric patients with acute myeloid leukemia

When hematopoietic stem cell transplant (HSCT) is necessary for children with acute myeloid leukemia (AML), there remains debate about the best stem cell source. Post-HSCT relapse is a common cause of mortality, and complications such as chronic graft versus host disease (cGVHD) are debilitating and life-threatening. To compare post-HSCT outcomes of different donor sources, we retrospectively analyzed consecutive transplants performed in several international centers from 2005 to 2015. A total of 317 patients were studied: 19% matched sibling donor (MSD), 23% matched unrelated donor (MUD), 39% umbilical cord blood (UCB), and 19% double UCB (dUCB) recipients. The median age at transplant was 10 years (range, 0.42-21 years), and median follow-up was 4.74 years (range, 4.02-5.39 years). Comparisons were made while controlling for patient, transplant, and disease characteristics. There were no differences in relapse, leukemia-free survival, or nonrelapse mortality. dUCB recipients had inferior survival compared with matched sibling recipients, but all other comparisons showed similar overall survival. Despite the majority of UCB transplants being HLA mismatched, the rates of cGVHD were low, especially compared with the well-matched MUD recipients (hazard ratio, 0.3; 95% confidence interval, 0.14-0.67; P = .02). The composite measure of cGVHD and leukemia-free survival (cGVHD-LFS), which represents both the quality of life and risk for mortality, was significantly better in the UCB compared with the MUD recipients (HR, 0.56; 95% confidence interval, 0.34-1; P = .03). In summary, the use of UCB is an excellent donor choice for pediatric patients with AML when a matched sibling cannot be identified.

Regional differences in access to hematopoietic stem cell transplantation among pediatric patients with acute myeloid leukemia

INTRODUCTION

Indications for hematopoietic stem cell transplantation (HSCT) in pediatric acute myeloid leukemia (AML) are primarily dependent on risk stratification at diagnosis and relapse status. We sought to determine whether access to HSCT is influenced by regional and socioeconomic factors.

METHODS

Children with newly diagnosed AML aged < 15 years between 2001 and 2015 were identified using the Cancer in Young People in Canada national population-based registry. Factors potentially associated with the receipt of HSCT were studied using univariate and multivariable logistic regression models.

RESULTS

Overall, 568 children with newly diagnosed AML were included and 262 (46%) received HSCT. A greater proportion of patients, 103/157 (65.6%), underwent HSCT after first or subsequent relapse compared to 159/411 (38.7%) patients who underwent transplant before relapse. Among patients for whom HSCT would be considered before relapse, factors associated with higher odds of HSCT in a multivariable analysis were: poor versus good-risk cytogenetics (Odds ratio [OR]: 30.0, 95% confidence interval [CI]: 7.7-117.0), diagnosis during 2012-2015 versus 2001-2006 (OR: 3.2, 95% CI: 1.6-6.3), diagnosis in eastern Canada versus central Canada (OR: 3.7, 95% CI: 1.9-7.3), and age 10-14 years versus age < 1 year (OR: 5.4, 95% CI: 2.3-12.8). Among patients for whom HSCT would be considered after first relapse, higher odds of HSCT was associated with diagnosis at a HSCT center (OR: 2.1, 95% CI: 1.1-4.1).

CONCLUSION

Patients diagnosed at a HSCT performing center and patients from eastern Canada had higher odds of receiving HSCT. This may suggest preferential access to HSCT for certain patients.

Perioperative Cardiothoracic and Vascular Risk in Childhood Cancer and its Survivors

CHILDREN with cancer and survivors of childhood cancer have an increased risk of cardiovascular disease, and this risk in the perioperative period must be understood. During diagnosis and treatment of pediatric cancer, multiple acute cardiovascular morbidities are possible, including anterior mediastinal mass, tamponade, hypertension, cardiomyopathy,and heart failure. Childhood cancer survivors reaching late childhood and adulthood experience substantially increased rates of cardiomyopathy, heart failure, valvular disease, pericardiac disease, ischemia, and arrhythmias. Despite considerable advances in the understanding and therapeutic options of pediatric malignancies, cardiac disease remains the most common treatment-related, noncancer cause of death in childhood cancer survivors. Increasingly, molecularly targeted agents, including small molecule inhibitors, are being incorporated into pediatric oncology. The acute and chronic risks associated with these newer therapeutic options in children are not yet well-described, which poses challenges for clinicians caring for these patients. In the present review, the unique risks factors, prevention strategies, and treatment of cardiovascular toxicities of the child with cancer and the childhood cancer survivor are examined, with an emphasis on the perioperative period.

Prevention and Treatment of Acute Graft-versus-Host Disease in Children, Adolescents, and Young Adults

Acute graft-versus-host disease (GVHD) continues to be a major cause of morbidity and mortality after allogeneic hematopoietic cell transplant (HCT) in pediatric patients (ie, children and adolescent and young adults) and limits broader application of the therapy. Pediatric HCT patients have faced major obstacles to access clinical trials that test new agents for GVHD prevention and treatment. According to a recent search, only 6 clinical trials of interventions for prevention or treatment of acute GVHD were conducted specifically in pediatric patients in the United States over the past decade, with 8 internationally. In this review, we summarize the studies that were performed and specifically enrolled and reported on pediatric patients after allogeneic HCT and provide a listing of studies currently under way.

Bone marrow harvesting from paediatric patients undergoing haematopoietic stem cell gene therapy

Collection of an adequate amount of autologous haematopoietic stem progenitor cells (HSPC) is required for ex vivo manipulation and successful engraftment for certain inherited disorders. Fifty-seven paediatric patients (age 0.5–11.4 years) underwent a bone marrow harvest for the purpose of HSPC gene therapy (GT), including adenosine deaminase-severe combined immunodeficiency (ADA-SCID), Wiskott–Aldrich syndrome (WAS) and metachromatic leukodystrophy (MLD) patients. Total nucleated cells and the percentage and absolute counts of CD34+ cells were calculated at defined steps of the procedure (harvest, CD34+ cell purification, transduction with the gene transfer vector and infusion of the medicinal product). A minimum CD34+ cell dose for infusion was 2 × 10⁶/kg, with an optimal target at 5–10 × 10⁶/kg. Median volume of bone marrow harvested was 34.2 ml/kg (range 14.2–56.6). The number of CD34+ cells collected correlated inversely with weight and age in all patients and particularly in the MLD children group. All patients reached the minimum target dose for infusion: median dose of CD34+ cells/kg infused was 10.3 × 10⁶/kg (3.7–25.9), with no difference among the three groups. Bone marrow harvest of volumes > 30 ml/kg in infants and children with ADA-SCID, WAS and MLD is well tolerated and allows obtaining an adequate dose of a medicinal product for HSPC-GT.

Ecological principle meets cancer treatment: treating children with acute myeloid leukemia with low-dose chemotherapy

Standard chemotherapy regimens for remission induction of pediatric acute myeloid leukemia (AML) are associated with significant morbidity and mortality. We performed a cohort study to determine the impact of reducing the intensity of remission induction chemotherapy on the outcomes of selected children with AML treated with a low-dose induction regimen plus granulocyte colony stimulating factor (G-CSF) (low-dose chemotherapy (LDC)/G-CSF). Complete response (CR) after two induction courses was attained in 87.0% (40/46) of patients receiving LDC/G-CSF. Post-remission therapy was offered to all patients, and included standard consolidation and/or stem cell transplantation. During the study period, an additional 94 consecutive children with AML treated with standard chemotherapy (SDC) for induction (80/94 (85.1%) of the patients attained CR after induction II, P = 0.953) and post-remission. In this non-randomized study, there were no significant differences in 4-year event-free (67.4 vs. 70.7%; P = 0.99) and overall (70.3 vs. 74.6%, P = 0.69) survival in the LDC/G-CSF and SDC cohorts, respectively. After the first course of induction, recovery of white blood cell (WBC) and platelet counts were significantly faster in patients receiving LDC/G-CSF than in those receiving SDC (11.5 vs. 18.5 d for WBCs (P < 0.001); 15.5 vs. 22.0 d for platelets (P < 0.001)). To examine the quality of molecular response, targeted deep sequencing was performed. Of 137 mutations detected at diagnosis in 20 children who attained hematological CR after two courses of LDC/G-CSF (n = 9) or SDC (n = 11), all of the mutations were below the reference value (variant allelic frequency <2.5%) after two courses, irrespective of the treatment group. In conclusion, children with AML receiving LDC/G-CSF appear to have similar outcomes and mutation clearance levels, but significantly lower toxicity than those receiving SDC. Thus, LDC/G-CSF should be further evaluated as an effective alternative to remission induction in pediatric AML.

Assessment of Late Mortality Risk After Allogeneic Blood or Marrow Transplantation Performed in Childhood

Importance

Allogeneic blood or marrow transplantation (BMT) is a curative option for malignant and nonmalignant diseases of childhood. However, little is known about trends in cause-specific late mortality in this population during the past 3 decades.

Objectives

To examine cause-specific late mortality among individuals who have lived 2 years or more after allogeneic BMT performed in childhood and whether rates of late mortality have changed over time.

Design, Setting, and Participants

A retrospective cohort study was conducted of individuals who lived 2 years or more after undergoing allogeneic BMT performed in childhood between January 1, 1974, and December 31, 2010. The end of follow-up was December 31, 2016.

Exposure

Allogeneic BMT performed in childhood.

Main Outcomes and Measures

All-cause mortality, relapse-related mortality, and non-relapse-related mortality. Data on vital status and causes of death were collected using medical records, the National Death Index Plus Program, and Accurint databases.

Results

Among 1388 individuals (559 females and 829 males) who lived 2 years or more after allogeneic BMT performed in childhood, the median age at transplantation was 14.6 years (range, 0-21 years). In this cohort, there was a total of 295 deaths, yielding an overall survival rate of 79.3% at 20 years after BMT. The leading causes of death were infection and/or chronic graft-vs-host disease (121 of 244 [49.6%]), primary disease (60 of 244 [24.6%]), and subsequent malignant neoplasms (45 of 244 [18.4%]). Overall, the cohort had a 14.4-fold increased risk for death (95% CI, 12.8-16.1) compared with the general population (292 deaths observed; 20.3 deaths expected). Relative mortality remained elevated at 25 years or more after BMT (standardized mortality ratio, 2.9; 95% CI, 2.0-4.1). The absolute excess risk for death from any cause was 12.0 per 1000 person-years (95% CI, 10.5-13.5). The cumulative incidence of non-relapse-related mortality exceeded that of relapse-related mortality throughout follow-up. The 10-year cumulative incidence of late mortality decreased over time (before 1990, 18.9%; 1990-1999, 12.8%; 2000-2010, 10.9%; P = .002); this decrease remained statistically significant after adjusting for demographic and clinical factors (referent group: <1990; 1990-1999: hazard ratio, 0.64; 95% CI, 0.47-0.89; P = .007; 2000-2010: hazard ratio, 0.49; 95% CI, 0.31-0.76; P = .002; P < .001 for trend).

Conclusions and Relevance

Late mortality among children undergoing allogeneic BMT has decreased during the past 3 decades. However, these patients remain at an elevated risk of late mortality even 25 years or more after transplantation when compared with the general population, necessitating lifelong follow-up.

CALIPSO: A Randomized Controlled Trial of Calfactant for Acute Lung Injury in Pediatric Stem Cell and Oncology Patients

To assess if calfactant reduces mortality among children with leukemia/lymphoma or after hematopoietic cell transplantation (HCT) with pediatric acute respiratory distress syndrome (PARDS), we conducted a multicenter, randomized, placebo-controlled, double-blinded trial in 17 pediatric intensive care units (PICUs) of tertiary care children's hospitals. Patients ages 18 months to 25 years with leukemia/lymphoma or having undergone HCT who required invasive mechanical ventilation for bilateral lung disease with an oxygenation index (OI) > 10 and <37 were studied. Interventions used were intratracheal instillation of either calfactant or air placebo (1 or 2 doses). Forty-three subjects were enrolled between November 2010 and June 2015: 26 assigned to calfactant and 17 to placebo. There were no significant differences in the primary outcome, which was survival to PICU discharge (adjusted hazard ratio of mortality for calfactant versus placebo, 1.78; 95% confidence interval, .53 to 6.05; P = .35), OI, functional outcomes, or ventilator-free days, adjusting for risk strata and Pediatric Risk of Mortality (PRISM) score. Despite the risk-stratified randomization, more allogeneic HCT patients received calfactant (76% and 39%, respectively) due to low recruitment at various sites. This imbalance is important because independent of treatment arm and while adjusting for PRISM score, those with allogeneic HCT had a nonsignificant higher likelihood of death at PICU discharge (adjusted odds ratio, 3.02; 95% confidence interval, .76 to 12.06; P = .12). Overall, 86% of the patients who survived to PICU discharge also were successfully discharged from the hospital. These data do not support the use of calfactant among this high mortality group of pediatric leukemia/lymphoma and/or HCT patients with PARDS to increase survival. In spite of poor enrollment, allogeneic HCT patients with PARDS appeared to be characterized by higher mortality than even other high-risk immunosuppressed groups. Conducting research among these children is challenging but necessary, because survival to PICU discharge usually results in successful discharge to home.

The case for plerixafor to replace filgrastim as the optimal agent to mobilize peripheral blood donors for allogeneic hematopoietic cell transplantation

Granulocyte colony-stimulating factor (G-CSF)-stimulated peripheral blood progenitor cells (G-PBs) from either a related or unrelated donor continue to be the preferred donor source for most allogeneic hematopoietic cell transplantation (HCT). Recently, the American Society for Blood and Marrow Transplantation has recommended marrow instead of G-PBs as an unrelated graft source due to its lower rate of chronic graft-versus-host disease (cGVHD). However, the use of marrow is limited by both clinical considerations (slower rate of engraftment and increased donor morbidity) and logistical considerations (use of operating room resources and increased physician utilization), so this recommendation has not been widely adopted. An optimal donor source would include the rapid engraftment characteristic and the low donor morbidity associated with G-PBs and a rate of cGVHD similar to or lower than that of marrow. Recent data suggest that plerixafor mobilized PBs (P-PBs) have the rapid engraftment characteristics of G-PBs in allogeneic HCT with less cGVHD. The biologic mechanism of the lower rate of cGVHD appears to be through mobilization of regulator natural killer cells and plasmacytoid dendritic cell precursors that are associated with lower acute and chronic GVHD compared with G-PBs and rapid engraftment characterized by rapid myeloid-repopulating capacity. We suggest that, based on the experience of the two Phase II clinical trials and the unique biology of plerixafor-mobilized donor product, it should be evaluated in Phase III trials as an approach to replacing G-CSF mobilization for allogeneic HCT.

Ruxolitinib as Salvage Therapy for Chronic Graft-versus-Host Disease

Chronic graft-versus-host disease (cGVHD) continues to be a major complication after allogeneic hematopoietic cell transplantation, significantly affecting patients' quality of life. A regimen of systemic corticosteroids is considered first-line therapy but is often associated with inadequate responses and multiple side effects. In patients with refractory disease, an evidenced-based consensus is lacking as to the single best approach to managing symptoms. Ruxolitinib, a selective JAK1/2 inhibitor, has recently gained favor as a second-line approach in patients with steroid-refractory cGVHD. In this retrospective study, we evaluated the outcomes of 46 patients who received ruxolitinib for cGVHD between March 2016 and December 2017 at our institution, and evaluated ruxolitinib's impact at 6 and 12 months, based on the National Institutes of Health Severity Scale, including organ-specific responses, and mean prednisone dose. Furthermore, we present the first reported probability of ruxolitinib's treatment failure-free survival (FFS) in patients with cGVHD. After 12 months of ruxolitinib therapy, complete response, partial response, and stable disease was observed in 13% (n = 6), 30.4% (n = 14), and 10.9% (n = 5) of patients, respectively. The 1-year probability of FFS was 54.2% (95% confidence interval, .388 to .673), and ruxolitinib use was associated with a reduction in prednisone dose. In conclusion, our data, which represent the largest cohort of patients with cGVHD reported to date, support the use of ruxolitinib for cGVHD refractory to steroids and currently available salvage therapies, discontinued due to lack of response and high cost.

Customization of the TRU-PBMT App (Technology Recordings to better Understand Pediatric Blood and Marrow Transplant)

PURPOSE

Our investigative team is integrating mobile health technologies into pediatric blood and marrow transplant (PBMT) care. We aim to evaluate whether patient-generated health data can be used to monitor health status and enhance symptom management. While there are numerous health-related apps, none address the symptoms or care needs specific to PBMT patients. This article describes development of the Technology Recording to better Understand Pediatric Blood and Marrow Transplant (TRU-PBMT) mobile application.

DESIGN AND METHODS

A one-time survey was distributed to PBMT clinicians, caregivers, and outpatients to elicit feedback and suggestions for the app's design.

RESULTS

Feedback from clinicians (n = 23), caregivers (n = 5), and PBMT outpatients (n = 4) indicated the app would be acceptable and useable with this group of patients between eight and eighteen years of age. Suggestions from respondents included: making the app language and graphics more child-friendly; adding symptoms such as fatigue, mucositis, bleeding; and a visual stool chart.

CONCLUSION

Patient, caregiver, and clinician feedback was valuable in creation of the TRU-PBMT app. We designed a pediatric friendly, PBMT-symptom-specific app, which we will test in future studies.

IMPLICATIONS FOR PRACTICE

This app facilitates patient-generated health data collection and informs health care plans.