Recurrent genetic lesions in patients who received allo-HSCT. (A) Mutational map of recurrent oncogenic mutations and truncating changes used for clonal tracking as well as chromosomal abnormalities (see “Methods” and supplemental Tables 1 and 10) identified before transplantation and/or at relapse in patients with MDS and related malignancies undergoing allo-HSCT. Hatched boxes indicate new genetic lesions identified at relapse and “X” indicates patients with biallelic TP53 mutations before transplantation based on either >60% VAF or loss of chromosome 17 at diagnosis (see supplemental Table 1 and source data file 1). “Months after Allo-HSCT” reflects the time of clinical relapse for relapse group and last observation time point for continuous-CR group. (B) ddPCR data in BM MNCs for the mutation within each patient with the highest VAF (%) at indicated days before allo-HSCT (last available BM sample before conditioning for allo-HSCT) in patients who relapsed (n = 14; all patients with available BM MNCs) 4 to 33 months after allo-HSCT compared with patients who remained in continuous CR (n = 10; all patients with available BM MNCs) for ≥66 months after allo-HSCT. (C) Violin plot of VAF for mutations shown in panel B in BM MNCs for all patients in continuous-CR and patients who relapsed before allo-HSCT. Dashed lines indicate the median and dotted lines indicate the quartiles. No statistical difference (P = .98, the Mann Whitney U test) was found between relapsed and continuous-CR groups. Pre–allo-HSCT samples correspond to pre–allo-HSCT samples in raw data source data file 1. CMML, chronic myelomonocytic leukemia; Del(5q), MDS with isolated del(5q); MDS-EB, MDS with excess blasts; MPN-u, myeloproliferative neoplasm unclassifiable; MDS-MLD, MDS with multilineage dysplasia; MDS-RS-MLD, MDS with multilineage dysplasia and ring sideroblasts; WHO, World Health Organization 2016 classification.