Minimal residual disease predicts outcomes in KMT2A-rearranged but not KMT2A-germline infant acute lymphoblastic leukemia: Report from Children’s Oncology Group study AALL0631

Faulk KE, Kairalla JA, Dreyer ZE, Carroll AJ, Heerema NA, Devidas M, Carroll WL, Raetz EA, Loh ML, Hunger SP, Borowitz M, Wang C, Guest E, Brown PA. Minimal residual disease predicts outcomes in KMT2A-rearranged but not KMT2A-germline infant acute lymphoblastic leukemia: Report from Children’s Oncology Group study AALL0631. Pediatr Blood Cancer. 2023 May 31;:e30467. doi: 10.1002/pbc.30467. [Epub ahead of print] PubMed PMID: 37259259; PubMed Central PMCID: PMC10687300.

We measured minimal residual disease (MRD) by multiparameter flow cytometry at three timepoints (TP) in 117 infants with KMT2A-rearranged and 58 with KMT2A-germline acute lymphoblastic leukemia (ALL) on Children’s Oncology Group AALL0631. For KMT2A-rearranged patients, 3-year event-free survival (EFS) by MRD-positive (≥0.01%) vs MRD-negative (<0.01%) was: TP1: 25%(+/−6%) vs 49%(+/−7%;p=0.0009); TP2: 21%(+/−8%) vs 47%(+/−7%;p<0.0001); and TP3: 22%(+/−14%) vs 51%(+/−6%;p=0.0178). For KMT2A-germline patients, 3-year EFS was: TP1: 88%(+/−12%) vs 87%(+/−5%;p=0.73); TP2: 100% vs 88%(+/−5%;p=0.24); and TP3: 100% vs 87%(+/−5%;p=0.53). MRD was a strong independent outcome predictor in KMT2A-rearranged, but not KMT2A-germline, infant ALL.