Assessment of droplet digital polymerase chain reaction for measuring BCR-ABL1 in chronic myeloid leukaemia in an international interlaboratory study

Stuart Scott*, Ashley Cartwright, Sebastian Francis, Liam Whitby, A. Pia Sanzone, André Mulder, Sara Galimberti, Stephanie Dulucq, Carole Mauté, Calogero Lauricella, Matthew Salmon, Susan Rose, Josh Willoughby, Nancy Boeckx, Niels Pallisgaard, Jacqueline Maier, Elisabeth O. Leibundgut, Hana Zizkova, Liuh Ling Goh, Chinh DuongWing F. Tang, Edmond Ma, Yogesh Shivakumar, Lan Beppu, Prasanthi Bhagavatula, Andrew Chantry

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Measurement of BCR activator of RhoGEF and GTPase -ABL proto-oncogene 1, non-receptor tyrosine kinase (BCR-ABL1) mRNA levels by reverse transcription quantitative polymerase chain reaction (RTqPCR) has been critical to treatment protocols and clinical trials in chronic myeloid leukaemia; however, interlaboratory variation remains a significant issue. Reverse transcriptase droplet digital PCR (RTddPCR) has shown potential to improve testing but a large-scale interlaboratory study is required to definitively establish this. In the present study, 10 BCR-ABL1-positive samples with levels ranging from molecular response (MR)1·0–MR5·0 were tested by 23 laboratories using RTddPCR with the QXDX BCR-ABL %IS kit. A subset of participants tested the samples using RTqPCR. All 23 participants using RTddPCR detected BCR-ABL1 in all samples to MR4·0. Detection rates for deep-response samples were 95·7% at MR4·5, 78·3% at MR4·7 and 87·0% at MR5·0. Interlaboratory coefficient of variation was indirectly proportional to BCR-ABL1 level ranging from 29·3% to 69·0%. Linearity ranged from 0·9330 to 1·000 (average 0·9936). When results were compared for the 11 participants who performed both RTddPCR and RTqPCR, RTddPCR showed a similar limit of detection to RTqPCR with reduced interlaboratory variation and better assay linearity. The ability to detect deep responses with RTddPCR, matched with an improved linearity and reduced interlaboratory variation will allow improved patient management, and is of particular importance for future clinical trials focussed on achieving and maintaining treatment-free remission.

Original languageEnglish
JournalBritish Journal of Haematology
Volume194
Issue number1
Pages (from-to)53-60
Number of pages8
ISSN0007-1048
DOIs
Publication statusPublished - Jul 2021
Externally publishedYes

Keywords

  • BCR-ABL1
  • CML
  • external quality assessment (EQA)
  • Quality
  • RTddPCR

Cite this