Volume–Outcome Relationships in Pediatric Acute Lymphoblastic Leukemia: Association Between Hospital Pediatric and Pediatric Oncology Volume With Mortality and Intensive Care Resources During Initial Therapy

A volume–outcome relationship has been shown in adult oncology. We investigated if an inverse association of volume and death exists in pediatric acute lymphoblastic leukemia (ALL) care. In assessing the association of volume and outcomes in a cohort of hospitalized pediatric ALL patients, we did not show an inverse relationship between volume and mortality or need for intensive care. Background There are few contemporary studies of volume–outcome relationships in pediatric oncology. Children with acute lymphoblastic leukemia (ALL) are treated at a wide variety of hospitals. We investigated if inpatient hospital volume influences outcomes. The objective of this study was to evaluate the relationship between inpatient pediatric and pediatric oncology volume and mortality and intensive care resources (ICU care). We hypothesized an inverse relationship between volume and these outcomes. Patients and Methods This was a retrospective cohort study. Patients 0 to 18 years of age in the Pediatric Health Information System or Perspective Premier Database from 2009 to 2011 with ALL were included. Exposures were considered as the average inpatient pediatric and pediatric oncology volume. The primary outcome was inpatient mortality; secondary outcome was need for ICU care. Results The included population comprised 3350 patients from 75 hospitals. The inpatient mortality rate was 0.86% (95% confidence interval, 0.58%-1.2%). In the unadjusted analysis, mortality increased as pediatric oncology volume increased from low (0%) to high volume (1.3%) (P = .009). The small number of deaths precluded multivariable analysis of this outcome. Pediatric and pediatric oncology volume was not associated with ICU care when we controlled for potential confounders. Conclusion Induction mortality was low. We did not observe an inverse relationship between volume and mortality or ICU care. This suggests that in a modern treatment era, treatment at a low-volume center might not be associated with increased mortality or ICU care in the first portion of therapy. This relationship should be evaluated in other oncology populations with higher mortality rates and with longer-term outcomes.