Candidacy for Extracorporeal Life Support in Children After Hematopoietic Cell Transplantation: A Position Paper From the Pediatric Acute Lung Injury and Sepsis Investigators Network’s Hematopoietic Cell Transplant and Cancer Immunotherapy Subgroup
OBJECTIVES: The last decade has seen improved outcomes for children requiring extracorporeal life support as well as for children undergoing hematopoietic cell transplantation. Thus, given the historically poor survival of hematopoietic cell transplantation patients using extracorporeal life support, the Pediatric Acute Lung Injury and Sepsis Investigators’ hematopoietic cell transplantation and cancer immunotherapy subgroup aimed to characterize the utility of extracorporeal life support in facilitating recovery from critical cardiorespiratory illnesses in pediatric hematopoietic cell transplantation patients. DATA SOURCES: All available published data were identified using a set of PubMed search terms for pediatric extracorporeal life support and hematopoietic cell transplantation. STUDY SELECTION: All articles that provided original reports of pediatric hematopoietic cell transplantation patients who underwent extracorporeal life support were included. Sixty-four manuscripts met search criteria. Twenty-four were included as primary reports of pediatric hematopoietic cell transplantation patients who underwent extracorporeal life support (11 were single case reports, four single institution case series, two multi-institution case series, and seven registry reports from Extracorporeal Life Support Organization, Pediatric Heath Information System, and Virtual Pediatric Systems). DATA EXTRACTION: All 24 articles were reviewed by first and last authors and a spread sheet was constructed including sample size, potential biases, and conclusions. DATA SYNTHESIS: Discussions regarding incorporation of available evidence into our clinical practice were held at biannual meetings, as well as through email and virtual meetings. An expert consensus was determined through these discussions and confirmed through a modified Delphi process. CONCLUSIONS: Extracorporeal life support in hematopoietic cell transplantation patients is being used with increasing frequency and potentially improving survival. The Pediatric Acute Lung Injury and Sepsis Investigators hematopoietic cell transplantation-cancer immunotherapy subgroup has developed a framework to guide physicians in decision-making surrounding extracorporeal life support candidacy in pediatric hematopoietic cell transplantation patients. In addition to standard extracorporeal life support considerations, candidacy in the hematopoietic cell transplantation population should consider the following six factors in order of consensus agreement: 1) patient comorbidities; 2) underlying disease necessitating hematopoietic cell transplantation; 3) hematopoietic cell transplantation toxicities, 4) family and patient desires for goals of care; 5) hematopoietic cell transplantation preparatory regimen; and 6) graft characteristics. Although risk assessment may be individualized, data are currently insufficient to clearly delineate ideal candidacy. Therefore, we urge the onco-critical care community to collaborate and capture data to provide better evidence to guide physicians’ decision-making in the future.
Neighborhood poverty and pediatric allogeneic hematopoietic cell transplantation outcomes: a CIBMTR analysis
Abstract Social determinants of health, including poverty, contribute significantly to health outcomes in the United States; however, their impact on pediatric hematopoietic cell transplantation (HCT) outcomes is poorly understood. We aimed to identify the association between neighborhood poverty and HCT outcomes for pediatric allogeneic HCT recipients in the Center for International Blood and Marrow Transplant Research database. We assembled 2 pediatric cohorts undergoing first allogeneic HCT from 2006 to 2015 at age ≤18 years, including 2053 children with malignant disease and 1696 children with nonmalignant disease. Neighborhood poverty exposure was defined a priori per the US Census definition as living in a high-poverty ZIP code (≥20% of persons below 100% federal poverty level) and used as the primary predictor in all analyses. Our primary outcome was overall survival (OS), defined as the time from HCT until death resulting from any cause. Secondary outcomes included relapse and transplantation-related mortality (TRM) in malignant disease, acute and chronic graft-versus-host disease, and infection in the first 100 days post-HCT. Among children undergoing transplantation for nonmalignant disease, neighborhood poverty was not associated with any HCT outcome. Among children undergoing transplantation for malignant disease, neighborhood poverty conferred an increased risk of TRM but was not associated with inferior OS or any other transplantation outcome. Among children with malignant disease, a key secondary finding was that children with Medicaid insurance experienced inferior OS and increased TRM compared with those with private insurance. These data suggest opportunities for future investigation of the effects of household-level poverty exposure on HCT outcomes in pediatric malignant disease to inform care delivery interventions.
Subsequent neoplasms and late mortality in children undergoing allogeneic transplantation for nonmalignant diseases
Abstract We examined the risk of subsequent neoplasms (SNs) and late mortality in children and adolescents undergoing allogeneic hematopoietic cell transplantation (HCT) for nonmalignant diseases (NMDs). We included 6028 patients (median age, 6 years; interquartile range, 1-11; range, <1 to 20) from the Center for International Blood and Marrow Transplant Research (1995-2012) registry. Standardized mortality ratios (SMRs) in 2-year survivors and standardized incidence ratios (SIRs) were calculated to compare mortality and SN rates with expected rates in the general population. Median follow-up of survivors was 7.8 years. Diagnoses included severe aplastic anemia (SAA; 24%), Fanconi anemia (FA; 10%), other marrow failure (6%), hemoglobinopathy (15%), immunodeficiency (23%), and metabolic/leukodystrophy syndrome (22%). Ten-year survival was 93% (95% confidence interval [95% CI], 92% to 94%; SMR, 4.2; 95% CI, 3.7-4.8). Seventy-one patients developed SNs (1.2%). Incidence was highest in FA (5.5%), SAA (1.1%), and other marrow failure syndromes (1.7%); for other NMDs, incidence was <1%. Hematologic (27%), oropharyngeal (25%), and skin cancers (13%) were most common. Leukemia risk was highest in the first 5 years posttransplantation; oropharyngeal, skin, liver, and thyroid tumors primarily occurred after 5 years. Despite a low number of SNs, patients had an 11-fold increased SN risk (SIR, 11; 95% CI, 8.9-13.9) compared with the general population. We report excellent long-term survival and low SN incidence in an international cohort of children undergoing HCT for NMDs. The risk of SN development was highest in patients with FA and marrow failure syndromes, highlighting the need for long-term posttransplantation surveillance in this population.
Area-Based Socioeconomic Status and Pediatric Allogeneic Hematopoietic Stem Cell Transplantation Outcomes: A CIBMTR Analysis
Abstract Introduction: Outcome disparities related to race and area-based socioeconomic status (SES) following allogeneic hematopoietic stem cell transplantation (allo-HCT) have been identified in adult patients [Baker et al. 2009]. The relationship between SES and outcomes in pediatric allo-HCT has not been previously described. Among a large cohort of pediatric allo-HCT recipients we sought to determine the impact of area-based poverty on 5-year outcomes of overall survival (OS), acute and chronic graft-versus-host-disease (aGVHD, cGVHD); as well as the short-term outcome of infection through day 100 . Methods: We utilized the Center for International Blood and Marrow Transplant Research (CIBMTR) database to examine the association of sociodemographic variables with outcomes in two cohorts of pediatric transplant recipients aged <=18 years who received allo-HCT at U.S. centers between 2006-2015. Cohort 1 (malignant) included 2053 children who received myeloablative conditioning for any malignancy. Cohort 2 (non-malignant) included 1696 children who received myeloablative or reduced-intensity conditioning for any non-malignant disease. Zip codes of child's residence were categorized as high-poverty area (>=20% households living below 100% federal poverty level (FPL)) versus low-poverty area (<20% households below 100% FPL) by linkage to U.S. Census data [Krieger et al. 2002]. Individual-level sociodemographic variables including insurance (Medicaid-only vs Other), race (Caucasian vs Black vs Other) and ethnicity (non-Hispanic vs Hispanic) were included as covariates. Cox regression was used to examine the effect of patient-related (age, performance status, insurance, race, and ethnicity), disease-related (disease type and status), and HCT-related (donor/graft type, CMV status, stem cell source, HLA match, donor age and gender, conditioning regimen and intensity, GVHD prophylaxis, year of HCT) variables on the outcomes of interest between the two area-based poverty groups. Results: Fifteen percent (N=299) of children in Cohort 1 lived in a high-poverty area; 35% (N=711) were insured by Medicaid-only; 11% (N=227) were African-American and 20% (N=417) Hispanic. Median follow-up of survivors was 74 months. In multivariable analysis, there was no association between area-based poverty and OS; however, OS was inferior in children with Medicaid-only insurance compared to those with private insurance (HR 1.22 (95% CI 1.06-1.40), p=0.0037) and in Black children compared to Caucasian (HR 2.02 (95% CI 1.10-3.73), p=0.0234). For the secondary outcomes of aGVHD, cGVHD or infection through day 100, there were no associations between area-based poverty, insurance, race, or ethnicity in multivariable analysis. To further explore the independent association of insurance with OS, we performed an ad hoc univariate analysis that demonstrated that insurance-related differences in OS for malignant disease appear to be driven by differences in treatment-related mortality (TRM) (5-year TRM: Medicaid-only 25% (95% CI 22-28) versus 18% (95% CI 16-21) other). Thirteen percent (N=228) of children in Cohort 2 lived in a high-poverty zip code; 35% were insured by Medicaid-only (N=597); 20% (N=332) were African-American and 20% (N=344) Hispanic. Median follow-up of survivors was 74 months. In multivariable analyses, there was no association between area-based poverty, insurance, race or ethnicity and any outcome. Conclusion: Area-based poverty is not associated with disparate outcomes in pediatric allo-HCT for malignant or non-malignant disease. In the setting of malignant disease, insurance-a household-level measure of socioeconomic status-and Black race are independently associated with inferior OS. These results suggest that future prospective investigation of more refined measures of household-level socioeconomic status may identify risk-factors for treatment-related mortality in this population. Disclosures No relevant conflicts of interest to declare.