NGS-based clonality testing is a sensitive and complementary method for MRD monitoring in acute lymphoblastic leukaemia

Aim: Measurable residual disease (MRD) has been recognised as an important prognostic marker in acute lymphoblastic leukaemia (ALL) alongside genetic profiling. Next generation sequencing (NGS) based clonality testing facilitates identification of the full range clonal populations with underlying DNA sequences, thereby offering improved sensitivity and specificity for MRD monitoring. Here, we interrogate clinical utility NGS-based assay monitoring ALL. Method: ALL diagnostic samples received between 2020–2022 were analysed parallel NGS flow cytometry (FC). levels at various clinically significant timepoints compared FC. For NGS, patients’ from bone marrow on LymphoTrackDx Assay platform (Invivoscribe). Sequencing was performed using Illumina MiSeq. Results: A total 23 patients identified (87% B-ALL, 13% T-ALL), detected clones 82.6% cases (19/23). Of these, a 75 time points assessed demonstrated 78.7% concordance FC (59/75). All discordance due to detecting below threshold detection In these discordant cases, positive by heralded relapse triggered therapy-related decisions. Conclusion: is complementary Where diagnosis, more sensitive than informs decision making.