Comparison of BCR::ABL (P210) mRNA levels detected by dPCR and qPCR methods in patients with chronic myeloid leukemia / 中华血液学杂志

ABSTRACT

Objective: To compare digital polymerase chain reaction (dPCR) and real-time quantitative PCR (qPCR) measurements of BCRABL (P210) mRNA expression in patients with chronic myeloid leukemia (CML) . Methods: In this non-interventional, cross-sectional study, BCRABL (P210) mRNA was simultaneously measured by dPCR and qPCR in peripheral blood samples collected from patients with CML who underwent tyrosine kinase inhibitor therapy and who achieved at least a complete cytogenetic response from September 2021 to February 2023 at Peking University People's Hospital. The difference, correlation, and agreement between the two methods were evaluated using the Wilcoxon signed-rank test, Spearman's correlation, and Bland-Altman analysis, respectively. Results: In total, 459 data pairs for BCRABL mRNA expression measured by dPCR and qPCR from 356 patients with CML were analyzed. There was a significant difference in BCRABL mRNA expression between the two methods (P<0.001). When analyzed by the depth of the molecular response (MR), a significant difference only existed for patients with ≥MR4.5 (P<0.001). No significant difference was observed for those who did not achieve a major MR (no MMR; P=0.922) or for those who achieved a major MR (MMR; P=0.723) or MR4 (P=0.099). There was a moderate correlation between the BCRABL mRNA expression between the two methods (r=0.761, P<0.001). However, the correlation gradually weakened or disappeared as the depth of the MR increased (no MMR r=0.929, P<0.001; MMR r=0.815, P<0.001; MR4 r=0.408, P<0.001; MR4.5 r=0.176, P=0.176). In addition, the agreement in BCRABL mRNA expression between the two methods in those with MR4.5 was weaker than other groups (no MMR ▉= 0.042, P=0.846; MMR▉=0.054, P=0.229; MR4▉=-0.020, P=0.399; MR4.5▉=-0.219, P<0.001) . Conclusions: dPCR is more accurate than qPCR for measuring BCRABL (P210) mRNA expression in patients with CML who achieve a stable deep MR.