Comparable on‐therapy mortality and supportive care requirements in Black and White patients following initial induction for pediatric acute myeloid leukemia

BackgroundBlack patients with acute myeloid leukemia (AML) are more likely to present with high acuity and consequently experience higher rates of induction mortality than white patients. Given the consistently identified racial disparities in overall survival (OS) among patients with AML, we aimed to evaluate whether there were sustained on-therapy racial differences in inpatient mortality, intensive care unit (ICU) requirements, or supportive care beyond initial induction.ProcedureWithin a retrospective cohort of 1239 children diagnosed with AML between 2004 and 2014 in the Pediatric Health Information System (PHIS) database who survived their initial course of induction chemotherapy, we compared on-therapy inpatient mortality, ICU-level care requirements, treatment course duration, cumulative length of hospital stay (LOS), and resource utilization after induction I by race.ResultsOver the period from the start of induction II through completion of frontline chemotherapy, there were no significant differences in mortality (adjusted odds ratios [OR], 1.01; 95% confidence intervals [CI], 0.41-2.48), ICU-level care requirements (adjusted OR, 0.93; 95% CI, 0.69-1.26), LOS (adjusted mean difference, 3.2 days; 95% CI, -2.3-9.6), or supportive care resource utilization for black patients relative to white patients. Course-specific analyses also demonstrated no differences by race.ConclusionAlthough black patients have higher acuity at presentation and higher induction mortality, such disparities do not persist over subsequent frontline chemotherapy treatment. This finding allows interventions aimed at reducing disparities to be directed at presentation and induction

Disparities in pediatric acute myeloid leukemia (AML) clinical trial enrollment

Equal access to clinical trial enrollment is important to ensure that findings are generalizable to the broader population. This study aimed to evaluate disparities in enrollment on pediatric oncology clinical trials. We assessed the relationship between patient characteristics and enrollment on COG trial AAML1031 in a cohort of pediatric patients with AML in the Pediatric Health Information System. The associations of enrollment with outcomes were evaluated. Non-Hispanic Black patients, infants, and patients from zip codes with a lower proportion of poverty were less likely to enroll (30% vs. 61%, p = .004; 34% vs. 58%, p = .003; 46% vs. 58%, p = .02). On-therapy mortality was similar among enrolled and nonenrolled patients (7.3% vs. 8.9%, p = .47). Differences in early mortality were more pronounced among nonenrolled patients compared to enrolled patients (3.0% vs. 0.5%, p = .03). Understanding the etiology of these disparities will inform strategies to ensure balanced access to clinical trials across patient populations

Bortezomib Inpatient Prescribing Practices in Free-Standing Children's Hospitals in the United States.

This study is a pharmacoepidemiologic description of pediatric bortezomib use. Exposure was identified through billing codes in patients admitted to US children's hospitals that participated with the Pediatric Health Information System between 2004 and 2013. Associated information on underlying diseases, demographics, institutional use, mortality, and physician type was collected. Exposure to bortezomib was identified in 314 patients. Hematologist/Oncologists prescribed half of the bortezomib used. Use increased during the study period. Inpatient volume was positively correlated with bortezomib utilization. Bortezomib use in pediatrics is increasing for a variety of diseases. Variation in use exists across institutions. Further studies are needed to characterize bortezomib's efficacy in pediatric diseases

Differential Depletion of Bone Marrow Resident B-ALL after Systemic Administration of Endosomal TLR Agonists

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. While frontline chemotherapy regimens are generally very effective, the prognosis for patients whose leukemia returns remains poor. The presence of measurable residual disease (MRD) in bone marrow at the completion of induction therapy is the strongest predictor of relapse, suggesting that strategies to eliminate the residual leukemic blasts from this niche could reduce the incidence of recurrence. We have previously reported that toll-like receptor (TLR) agonists achieve durable T cell-mediated protection in transplantable cell line-based models of B cell precursor leukemia (B-ALL). However, the successful application of TLR agonist therapy in an MRD setting would require the induction of anti-leukemic immune activity specifically in the bone marrow, a site of the chemotherapy-resistant leukemic blasts. In this study, we compare the organ-specific depletion of human and mouse primary B-ALL cells after systemic administration of endosomal TLR agonists. Despite comparable splenic responses, only the TLR9 agonist induced strong innate immune responses in the bone marrow and achieved a near-complete elimination of B-ALL cells. This pattern of response was associated with the most significantly prolonged disease-free survival. Overall, our findings identify innate immune activity in the bone marrow that is associated with durable TLR-induced protection against B-ALL outgrowth.Medicine, Faculty ofNon UBCPathology and Laboratory Medicine, Department ofPediatrics, Department ofReviewedFacult

Creation of a pediatric mature B-cell non-Hodgkin lymphoma cohort within the Pediatric Health Information System Database.

Mature B-cell non-Hodgkin lymphoma (B-NHL) constitutes a collection of relatively rare pediatric malignancies. In order to utilize administrative data to perform large-scale epidemiologic studies within this population, a two-step process was used to assemble a 12-year cohort of B-NHL patients treated between 2004 and 2015 within the Pediatric Health Information System database. Patients were identified by ICD-9 codes, and their chemotherapy data were then manually reviewed against standard B-NHL treatment regimens. A total of 1,409 patients were eligible for cohort inclusion. This process was validated at a single center, utilizing both an institutional tumor registry and medical record review as the gold standards. The validation demonstrated appropriate sensitivity (91.5%) and positive predictive value (95.1%) to allow for the future use of this cohort for epidemiologic and comparative effectiveness research