The following is a summary of “Reproducibility of low-level residual myeloma immunoglobulin detection using ultra-deep sequencing,” published in the March 2023 issue of Hematology by Cédile et al.
The second most prevalent hematologic malignancy is multiple myeloma, a neoplasm of mature B-cells. Despite the progress in therapeutic interventions, the ailment remains refractory, resulting in over 100,000 fatalities globally annually. As per the International Myeloma Working Group guidelines, it is advisable to consider measurable residual disease (MRD) at a sensitivity level of 10-5 or higher for practical purposes. The utilization of next-generation sequencing (NGS) has presented novel prospects through the complete sequencing of clonal rearrangements of the immunoglobulin heavy chain (IGH) locus in B-cell malignancies. The potential of detecting a single cancerous cell among a million other B cells is gaining interest as a predictive factor in patients who have remained MRD-negative. However, achieving consistent sensitivity levels is difficult due to sample stochasticity and the significant amount of deoxyribonucleic acid (DNA) needed for library preparation. In the aforementioned study, ultra-deep sequencing of rearranged IGH was employed to examine the reliability and uniformity with a targeted sensitivity level of 10-5.
In this controlled environment, the researcher’s data has yielded consistent minimal residual disease (MRD) detection at a rate of 1.2 clonal cells per 100,000 analyzed cells, with reliable longitudinal reproducibility. Researcher’s findings indicate a minimal occurrence of false-negative results when utilizing 4-5 replicates and 700-800 ng DNA per sequencing replicate. In summary, incorporating an internal control into the replicates facilitated the normalization of clonal cells for minimal residual disease assessment as a reliable reference point. These observations could guide MRD-level documentation and evaluations across different medical facilities.