[Clinical significance of minimal residual disease in B-lineage acute lymphoblastic leukemia pediatric patients with different fusion gene backgrounds].

Objective To study the clinical significance of minimal residual disease (MRD) in B-lineage acute lymphoblastic leukemia (B-ALL) pediatric patients with different fusion gene backgrounds. Methods A retrospective analysis was performed on the medical data of 441 B-ALL children who were treated from January 2008 to April 2015. Among the 441 children, 336 had negative fusion gene, 79 had positive ETV6-RUNX1 fusion gene, and 26 had positive E2A-PBX1 fusion gene. Flow cytometry was used to detect MRD, and the influence of MRD on day 15 (TP1), day 33 (TP2), and week 12 (TP3) of induction therapy on prognosis was analyzed. Results In patients with negative fusion gene, the positive MRD group had significantly lower overall survival (OS) rate and event-free survival (EFS) rate (P 0.05). Conclusions MRD has the most definite prognostic significance in pediatric B-ALL patients with negative fusion gene, while it has unsatisfactory prognostic significance in those with positive ETV6-RUNX1 or positive E2A-PBX1.