Access to Hematopoietic Stem Cell Transplantation among Pediatric Patients with Acute Lymphoblastic Leukemia: A Population-Based Analysis

Abstract

Access to hematopoietic stem cell transplantation (HSCT) in pediatric acute lymphoblastic leukemia (ALL) primarily depends on disease-related factors but may be influenced by social and economic determinants. We included all children aged < 15 years with newly diagnosed ALL in Canada between 2001 and 2018 using the Cancer in Young People in Canada national registry. We examined factors potentially associated with the likelihood of receiving HSCT using univariate and multivariable logistic regression models. A total of 3992 patients with newly diagnosed ALL were included. Three hundred twenty-five (8.1%) received an HSCT and formed the transplant cohort. In multivariable analysis factors independently associated with an increased odds of receiving HSCT were male sex (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.05 to 1.93), initial WBC ≥ 50,000 × 10⁹/L (OR, 1.58; 95% CI, 1.09 to 2.28), mixed phenotype acute leukemia relative to B-precursor ALL (OR, 34.32; 95% CI, 16.64 to 70.79), T cell relative to B-precursor ALL (OR, 1.77; 95% CI, 1.07 to 2.91), unfavorable relative to standard cytogenetics (OR, 3.96; 95% CI, 2.56 to 6.12), and relapse before HSCT (OR, 32.77; 95%, 23.89 to 44.96). No association was found between race, neighborhood income quintile or region at diagnosis, and receipt of HSCT. Diagnosis at an HSCT treating center (OR, 1.51; 95% CI, 1.09 to 2.09) and residential distance from the ALL treating center (OR, 1.84 for ≥300 km compared with <100 km; 95% CI, 1.17 to 2.91) were associated with higher odds of receiving HSCT. In a publically funded healthcare system, children with ALL had equitable access to HSCT, which was largely governed by biologic disease-related factors. Patients diagnosed at an HSCT performing center and patients who live farthest away from their treatment center had higher odds of receiving HSCT, although the effect was small, possibly suggesting preferential referral to HSCT for some patients.

Keywords: Access; Acute lymphoblastic leukemia; Geographic; Hematopoietic stem cell transplant; Publically funded healthcare; Sociodemographic; Universal healthcare.