Table 3 Comparison between flow cytometry and IGH/IGK rearrangements identified by NGS in MRD monitoring
From: Next-generation sequencing for MRD monitoring in B-lineage malignancies: from bench to bedside
Items | Multiparameter Flow Cytometry | IG NGS-based Clonality Assessment | Droplet Digital PCR |
|---|---|---|---|
Information offered | Proportion of cells, morphological features, immunophenotypic characteristics | Genetic alterations, immune repertoire | Genetic alteration, breakpoints involved in specific translocations |
Turn-around time | 24–48 h | 5–7 days | 24–48 h |
Sample type | Bone marrow aspirates (more frequently) or peripheral blood | Bone marrow aspirates or peripheral blood | Bone marrow aspirates or peripheral blood |
Sample quality | Fresh samples acquired within 24–28 h or DMSO-preserved samples | Fresh samples or preserved samples (FFPE, cryo-preserved samples, etc.) | Fresh samples or preserved samples (FFPE, cryo-preserved samples etc.) |
Sample quantity | Relatively large (1 × 105 ~ 1.5 × 106 mononuclear cells) [118] | Small, but high DNA input is required for the identification of index clones (DNA input of 40–200 ng) [117] | Small, suitable for cases with low tumor burden or positive but not quantifiable qPCR results (DNA input of at least 150 ng) [119] |
Application range | minority of patients, dependent on the target selected [112, 113] | ||
Sensitivity | 1 × 10–6 [19] | 1 × 10–5 [110] | |
Operation procedure | Simplified steps | Relatively complicated steps | Relatively complicated steps |
Analysis and Interpretation | Subjective, a high level of expertise is required | Objective, the analysis is automatically completed by the software | Objective, the analysis is automatically completed by the software |
Clonality assessment | Clonal heterogeneity at the genetic level cannot be detected, but cell heterogeneity can be identified | Subclones and clonal evolution at the genetic level can be identified | Clonal heterogeneity at the genetic level and cellular level cannot be detected |
Cost | Relatively cheap | Expensive | Relatively expensive |