Droplet Digital PCR Is a Robust Tool for Monitoring Minimal Residual Disease in Adult Philadelphia-Positive Acute Lymphoblastic Leukemia

The breakpoint cluster region–abelson 1 p190 fusion transcript is the most frequent variant observed in Philadelphia-positive (Ph+) acute lymphoblastic leukemia (ALL). Qualitative-PCR and real-time quantitative PCR are the currently used methods to monitor minimal residual disease (MRD) in Ph+？ALL patients; for the latter, full standardization and an international quality validation are lacking. Here, we developed a droplet digital PCR (ddPCR) assay for MRD monitoring in p190+？ALL cases. The analytical performance was assessed by the limit-of-detection determination, showing a reliability, sensitivity, and precision of the assay of up to 0.001%.