The measurement of residual leukemia levels, "minimal residual disease" (MRD), during therapy has now emerged as the most important predictor the outcome in acute lymphoblastic leukemia (ALL). As a result, risk-classifications based on MRD assessment has become an essential part of determining disease risk and directing therapeutic approach for children and adults with ALL.
Recently, next-generation sequencing (NGS) techniques measuring immunoglobulin (Ig) or T-cell receptor (TCR) clonal rearrangements as a method of detecting MRD have been introduced. These approaches expand the sensitivity of MRD detection to as high as 1 in 10,000,000 cells and have been shown to be predictive of relapse in children with ALL receiving standard chemotherapy.
In this study, the investigators will determine the sensitivity and specificity of IgH-V(D)J NGS and compared its capacity to measure MRD with that of flow cytometry using diagnostic and follow-up samples from more than 100 patients with ALL. Patients under age of 18 years with newly diagnosed ALL will be recruited and receive the treatment strategy of (SCCLG)-ALL 2016. After identifying a trackable clone in diagnostic samples (Baseline), MRD was measured using IgH-V(D)J NGS and FCM on bone marrow at 3 time-points: fifteen days after induction therapy (D15), thirty-three days after induction therapy (D33) and then at the end of induction therapy. Event-free survival (EFS), Relapse-free survival (RFS) and overall survival (OS) were assessed.
