NGS-based clonality analysis identifies clonally related cHL recurrences. (A) Representative data sets indicating NGS-based detection of IG gene rearrangements in paired diagnosis and recurrence tissue samples of 2 patients with clonally related relapsed cHL (cases 12 and 32). For each patient, the data for 2 clonal IG gene rearrangements are shown; IGKV-IGKJ and IGKV/intron RSS-KDE for case 12 and IGHV-IGHD-IGHJ and IGKV/intron RSS-KDE for case 32. The specific clonotype for the dominant IG gene rearrangement is indicated in green. On the x-axis, the junction length in amino acids (junction aa length) is shown, and the abundancy of clonotypes is shown in percentages on the y-axis. (B) Summary of clonality assessment detecting relapsed cHL in 24 patients, together with EBV status, cHL subtype, and time interval between the paired cHL samples. CT, clonality threshold; D, primary diagnosis sample; NOS, not otherwise specified; R, recurrence sample; y, years.