Hematopoietic Stem-Cell Transplantation Does Not Improve the Poor Outcome of Children With Hypodiploid Acute Lymphoblastic Leukemia: A Report From Children’s Oncology Group

McNeer JL, Devidas M, Dai Y, Carroll AJ, Heerema NA, Gastier-Foster JM, Kahwash SB, Borowitz MJ, Wood BL, Larsen E, Maloney KW, Mattano L, Winick NJ, Schultz KR, Hunger SP, Carroll WL, Loh ML, Raetz EA. Hematopoietic Stem-Cell Transplantation Does Not Improve the Poor Outcome of Children With Hypodiploid Acute Lymphoblastic Leukemia: A Report From Children’s Oncology Group. J Clin Oncol. 2019 Apr 1;37(10):780-789. doi: 10.1200/JCO.18.00884. Epub 2019 Feb 11. PMID: 30742559; PMCID: PMC6440386.

Children and young adults with hypodiploid B-lymphoblastic leukemia (B-ALL) fare poorly and hematopoietic stem-cell transplantation (HSCT) is often pursued in first complete remission (CR1). We retrospectively reviewed the outcomes of children and young adults with hypodiploid B-ALL who were enrolled in recent Children’s Oncology Group (COG) trials to evaluate the impact of HSCT on outcome. Cytogenetic analyses and DNA index were performed at COG-approved laboratories, and hypodiploidy was defined as modal chromosome number less than 44 and/or DNA index less than 0.81. Minimal residual disease (MRD) was determined centrally using flow cytometry at two reference laboratories. Patients with hypodiploid ALL came off protocol therapy postinduction and we retrospectively collected details on their subsequent therapy and outcomes. Event-free survival (EFS) and overall survival (OS) were estimated for the cohort.