<p>Ig gene (IG) clonality analysis has an important role in the distinction of benign and malignant B-cell lymphoid proliferations and is mostly performed with the conventional EuroClonality/BIOMED-2 multiplex PCR protocol and GeneScan fragment size analysis. Recently, the EuroClonality-NGS Working Group developed a method for next-generation sequencing (NGS)–based IG clonality analysis. Herein, we report the results of an international multicenter biological validation of this novel method compared with the gold standard EuroClonality/BIOMED-2 protocol, based on 209 specimens of reactive and neoplastic lymphoproliferations. NGS-based IG clonality analysis showed a high interlaboratory concordance (99%) and high concordance with conventional clonality analysis (98%) for the molecular conclusion. Detailed analysis of the individual IG heavy chain and kappa light chain targets showed that NGS-based clonality analysis was more often able to detect a clonal rearrangement or yield an interpretable result. NGS-based and conventional clonality analysis detected a clone in 96% and 95% of B-cell neoplasms, respectively, and all but one of the reactive cases were scored polyclonal. We conclude that NGS-based IG clonality analysis performs comparable to conventional clonality analysis. We provide critical parameters for interpretation and discuss a first step toward a quantitative scoring approach for NGS clonality results. Considering the advantages of NGS-based clonality analysis, including its high sensitivity and possibilities for accurate clonal comparison, this supports implementation in diagnostic practice.</p>

doi.org/10.1016/j.jmoldx.2021.06.005, hdl.handle.net/1765/136288
Journal of Molecular Diagnostics
Erasmus MC: University Medical Center Rotterdam

EuroClonality-NGS Working Group, Michiel van den Brand, Jos Rijntjes, Markus Möbs, Julia Steinhilber, M.Y. (Michele) van der Klift, … Patricia J.T.A. Groenen. (2021). Next-Generation Sequencing–Based Clonality Assessment of Ig Gene Rearrangements. Journal of Molecular Diagnostics, 23(9), 1105–1115. doi:10.1016/j.jmoldx.2021.06.005