Fig 1.
A summary of the methods and their specific approaches to the monitoring of multiple myeloma utilized in this study.
NGS = next-generation sequencing, ddPCR = droplet digital PCR, IGH-MMSET qPCR = IgH::MMSET fusion transcript specific reverse transcription qPCR, MFC = multiparametric flow cytometry, IgH/L = immunoglobulin heavy/light chain (respectively), Ig V-J = immunoglobulin V and J gene segments, CDR3 = complementarity determining region 3, FA = fractional abundance, MMSET = multiple myeloma SET domain-containing protein (also called NSD2 = nuclear SET domain-containing protein 2), Chr = chromosome.
Fig 2.
Schematic overview of each patient’s follow-up schedule with the acquired sample types.
The diagnostic / target defining timepoint is indicated as ‘D/0’. Bone marrow samples are marked with a green circle, peripheral blood mononuclear cell samples with a reddish square, and cell-free DNA samples with a blue triangle over each monitoring timepoint. PBMC = peripheral blood mononuclear cells, cfDNA = cell-free DNA.
Table 1.
The identified heavy and light chain myeloma targets.
Table 2.
Spearman correlation analyses of our methods with M-protein data.
Table 3.
Spearman correlation analyses of our relevant methods with FLC data.
Fig 3.
Summary graph of patient MM-2, representing the responsive patient group.
The right graph summarizes relevant clinical data, the left graph contains the results of our methods at each monitoring timepoint, the latter are indicated as days from diagnosis on both graphs. The grey dashed line indicates the empirical threshold of NGS-positive results. The y-axis depicts the log10 of the data from our methods; additionally, it was broken to indicate 0 values for better visualization. NGS-H and NGS-L = Ig heavy chain specific and Ig light chain specific NGS (respectively), ddPCR = droplet digital PCR, FA = fractional abundance, BM = bone marrow, PBMC = peripheral blood mononuclear cells, cfDNA = cell-free DNA, D/0 = diagnosis, FLC = free light chain, CR = complete response.
Fig 4.
Summary graph of patient MM-6, representing the rapid refractory patient group.
The right graph summarizes relevant clinical data, the left graph contains the results of our methods at each monitoring timepoint, the latter are indicated as days from diagnosis on both graphs. These data did not go under the empirical threshold of NGS-positive results, so the grey dashed line is only shown to uniformize the graphs. The y-axis depicts the log10 of the data from our methods; additionally, it was broken to indicate 0 values for better visualization–in this case it was done only to uniformize the graphs. NGS-H and NGS-L = Ig heavy chain specific and Ig light chain specific NGS (respectively), ddPCR = droplet digital PCR, FA = fractional abundance, BM = bone marrow, PBMC = peripheral blood mononuclear cells, cfDNA = cell-free DNA, IGH-MMSET = IgH::MMSET fusion transcript specific RT-qPCR, MFC = multiparametric flow cytometry, D/0 = diagnosis, FLC = free light chain, vgPR = very good partial response. MFC measurement from the bone marrow is indicated with a darker green frame of the respective data point.
Fig 5.
Summary graph of patient MM-7, representing the relapsing patient group.
The right graph summarizes relevant clinical data, the left graph contains the results of our methods at each monitoring timepoint, the latter are indicated as days from diagnosis on both graphs. The grey dashed line indicates the empirical threshold of NGS-positive results. The y-axis depicts the log10 of the data from our methods; additionally, it was broken to indicate 0 values for better visualization. NGS-H and NGS-L = Ig heavy chain specific and Ig light chain specific NGS (respectively), ddPCR = droplet digital PCR, FA = fractional abundance, BM = bone marrow, PBMC = peripheral blood mononuclear cells, cfDNA = cell-free DNA, IGH-MMSET = IgH::MMSET fusion transcript specific RT-qPCR, MFC = multiparametric flow cytometry, D/0 = diagnosis, FLC = free light chain. MFC measurement from the bone marrow is indicated with a darker green frame of the respective data points.
Fig 6.
Summary graph of patient MM-8 from the relapsing patient group, further providing a valuable insight into disease monitoring and early relapse detection.
The patient relapsed two months after the last follow-up timepoint. The right graph summarizes relevant clinical data, the left graph contains the results of our methods at each monitoring timepoint, the latter are indicated as days from diagnosis on both graphs. The grey dashed line indicates the empirical threshold of NGS-positive results. The y-axis depicts the log10 of the data from our methods; additionally, it was broken to indicate 0 values for better visualization. NGS-H and NGS-L = Ig heavy chain specific and Ig light chain specific NGS (respectively), ddPCR = droplet digital PCR, FA = fractional abundance, BM = bone marrow, PBMC = peripheral blood mononuclear cells, cfDNA = cell-free DNA, IGH-MMSET = IgH::MMSET fusion transcript specific RT-qPCR, MFC = multiparametric flow cytometry, D/0 = diagnosis, FLC = free light chain, SD = stable disease. MFC measurement from the bone marrow is indicated with a darker green frame of the respective data point.