Hematologic Recovery Associated With Better Survival in Pediatric AML

A study presented at the Society of Hematologic Oncology 2024 Annual Meeting suggested that although recovery of at least one lineage before proceeding to the next cycle of treatment is crucial, achieving full hematologic count recovery is associated with better survival outcomes in pediatric patients with acute myeloid leukemia (AML).

The investigators aimed to evaluate the impact of complete remission (CR) and incomplete hematologic count recovery (CRi) on relapse rates and survival outcomes in pediatric patients with AML and intermediate- and low-risk profiles.

The study included pediatric patients who achieved morphologic remission and minimal residual disease negativity confirmed by flow cytometry and polymerase chain reaction on day 21 after the first induction course (Induction I). Investigators assessed whether patients reached a peripheral absolute neutrophil count (ANC) of 500 cells/µL and a non-transfused platelet count of 50,000 cells/µL before the second induction cycle (Induction II), with assessments conducted on day 28 after Induction I. The study evaluated recovery proportions at day 28 based on both ANC and platelet count recoveries.

The median follow-up time for patients alive at last contact was 60.7 months. The analysis revealed a significant association between hematologic recovery parameters and overall survival (OS; P=0.049) but not relapse-free survival (RFS; P=0.33). The study compared three subgroups: CRi, CR, and CRh (complete remission with hematologic recovery).

Five-year RFS for the CRi group was 57.6%, compared with 81.6% for the CR group and 81.1% for the CRh group (P=0.453). For five-year OS, the CRi group had a rate of 64.6%, whereas the CR and CRh groups had rates of 81.1% and 88.5%, respectively (P=0.49). Additionally, patients in the low-risk (LR) group exhibited better five-year OS and RFS (85.5% and 82.8%, respectively; P=0.038) compared with the standard-risk (SR) group (69% and 61.5%, respectively; P<0.022).

“Even with at least one lineage recovery before going on to the next cycle, better survival probability may be associated with full hematologic count recovery if linked to early illness clearing,” the investigators concluded.

Reference

Shahin N, Hammad M, Hafez H, et al. Impact of delayed hematological recovery on outcome in acute myeloid leukemia with negative minimal residual disease post induction I in children. Abstract #AML-002. Presented at the Society of Hematologic Oncology 2024 Annual Meeting; September 4-7, 2024; Houston, Texas.