Chromosome 1q gain and/or 6q loss in PFA show increased prevalence at recurrence and are associated with a high rate of mortality. (A) Average copy numbers for all chromosome arms at presentation (P), 1st recurrence (R1), 2nd recurrence (R2) and subsequent recurrences and autopsy (R3+) and a publicly available cohort of presentation PFA samples published by Pajtler et al.2 (Pajtler P). The average CNV per sample and percentage of patients with a balanced genome are included. (B) Sankey plot showing changes in (i) 1q+ and 6q− co-occurrence (1q+ and 6q−), (ii) 1q+ with wildtype 6q (1q+), (iii) 6q− with wildtype 1q (6q−) and (iv) wildtype 1q/6q, between presentation and 1st recurrence. (C) example of translocation of chromosome 1q and 6q in UPN-811-R3, resulting in derivative chromosome 6 with one copy of 6q replaced with 1q. Overall survival from presentation for (D) 1q+,(E) 6q−, and (F) combined 1q+ and/or 6q− in the recurrence cohort (n = 88) with CNVs considered as time dependent variables to incorporate CNV changes at recurrence.