According to a recent retrospective review published in the Journal of Clinical Oncology, children with hypodiploid B-lymphoblastic leukemia (B-ALL) did not appear to benefit from hematopoietic stem cell transplantation (HSCT) following first complete remission (CR).1
Hypodiploid B-ALL is characterized by leukemic cells with 45 chromosomes or less, which is considered to be an unfavorable karyotypic feature in cells of children with this disease. Intensive treatment followed by HSCT after first CR is often administered to patients with hypodiploid B-ALL. Nevertheless, whether HSCT is beneficial in this setting has only recently been investigated.
This study was a review of the medical records of 8522 patients with high-risk or standard-risk B-ALL (judged according to National Cancer Institute parameters) who received induction therapy while enrolled in Children’s Oncology Group trials from 2003 to 2011.
In the subgroup with hypodiploid disease (representing 1.5% of the overall cohort), rates of 5-year event-free survival (EFS) and overall survival (OS) were 52.2% and 58.9%, respectively, compared with a 5-year EFS of 85.2% and a 5-year OS of 91.8% for patients with non-hypodiploid disease (P <.001).
More than 98% of patients with hypodiploid B-ALL achieved a CR following induction therapy. Of the 113 patients in this group for whom data on HSCT following first CR were available, 61 underwent treatment with HSCT following induction therapy, whereas 52 did not.
Rates of 5-year EFS was 57.4% and 47.8% for those receiving or not receiving HSCT, respectively (P =.49). Similarly, no significant difference was observed in the rates of 5-year OS for those treated with (66.2%) or without (53.8%) HSCT (P =.34). Although minimal residual disease of <0.01% was associated with a more favorable prognosis in patients with hypodiploid B-ALL, it was not found to be a predictive indicator of benefit from HSCT.
Results from a similarly designed retrospective analysis of 306 patients with hypodiploid B-ALL enrolled in clinical trials between 1997 and 2013 showed 5-year EFS and OS rates of 55.1% and 61.2%, respectively, for the overall patient cohort.2 Similar to the findings of the study of McNeer and colleagues,1 no significant differences in the rates of 5-year OS were observed when subgroups of patients receiving (59%) or not receiving HSCT (51.5%) were compared (P =.16).2
The absence of minimal residual disease (ie, MRD-negative status) as a positive prognostic factor was also identified in this study. Neither patients with MRD-positive status (P =.29) nor those with MRD-negative status (P =.81) were found to have a disease-free survival benefit from HSCT following first CR when compared with subgroups of similarly classified patients who did not receive HSCT.2
- McNeer JL, Devidas M, Dai Y, et al. Hematopoietic stem cell transplantation does not improve the poor outcome of children with hypodiploid acute lymphoblastic leukemia: A report from Children’s Oncology Group [published online February 11, 2019]. J Clin Oncol. doi: 10.1200/JCO.18.00884
- Pui CH, Rebora P, Schrappe M, et al. Outcome of children with hypodiploid acute lymphoblastic leukemia: A retrospective multinational study [published online January 18, 2019]. J Clin Oncol. doi: 10.1200/JCO.18.00822with