Use of Droplet Digital Polymerase Chain Reaction for Detecting Minimal Residual Disease: A Prospective Multi-Institutional Study

Abstract

Background/aim: Droplet digital polymerase chain reaction (ddPCR) is an exact method of measuring nucleic acids. The aim of this prospective study was to evaluate minimal residual disease (MRD) using ddPCR in chronic myeloid leukemia (CML) patients.

Patients and methods: Between May 2013 and November 2014, CML patients treated with nilotinib were enrolled in our study. BCR/ABL1 transcripts levels were evaluated using ddPCR at the first time of complete molecular response (CMR). We enrolled 15 patients from 7 Institutions. The treatment period and median follow-up period were 45 months and 47 months, respectively.

Results: Patients with a high level of BCR/ABL1 transcript had a greater tendency to lose the CMR during the follow-up period (p=0.095). In addition, patients with a low level of BCR/ABL1 transcript showed a longer duration of CMR compared to those with a high level (p=0.032).

Conclusion: We found that ddPCR is a sensitive method for detecting MRD and that MRD could affect the duration of the treatment response.

Keywords: Chronic myeloid leukemia; complete molecular response; droplet digital polymerase chain reaction; minimal residual disease; treatment outcome.