E-MTAB-11954
Outcomes of Allogeneic Hematopoietic Cell Transplantation in Adults with fusions associated with Ph-like ALL
Allogenic hematopoietic cell transplantation (alloHCT) is a well-established curative modality for adults with high-risk ALL; yet large data describing alloHCT outcomes in Philadelphia (Ph)-like ALL is lacking. We retrospectively analyzed archived DNA samples from consecutive adults with B-cell Ph-negative ALL who underwent alloHCT in complete remission (CR) (n= 127) at our center between 2006 and 2020. Identification of fusions associated with Ph-like were performed using accumulative results from RNAseq, conventional cytogenetics, FISH, and whole genome array studies. Fusions associated with Ph-like were detected in 56 (44%) patients, of whom 38 were carrying CRLF2r;  and the rest (n=18) were non-CRLF2r. Compared to other non-Ph-like (n=71), patients with fusions associated with Ph-like ALL were more frequently Hispanic (P=0.008), less frequently carried high-risk cytogenetics (P<0.001), and more likely to receive blinatumomab prior to HCT (P=0.019). With the median follow-up of 3.5 years, patients with Ph-like ALL fusions had comparable post-transplant outcomes compared to other B-cell ALL: 3-year relapse-free survival (RFS) [41% vs. 44%, P=0.36], overall survival (OS) [51% vs. 50%, P=0.59] and relapse [37% vs. 31%, P=0.47].  In multivariable analysis, age (P= 0.023), disease status at the time of transplant (P<0.001), and donor type (P=0.015) influenced OS. RFS (primary endpoint) was significantly influenced by disease status (P<0.001) and conditioning regimen intensity (P=0.014). Relapse rate was associated with disease status (P=0.028) and conditioning regimen intensity (P=0.028). In conclusion, our data suggest that alloHCT consolidation results in similarly favorable survival outcomes in adult patients with Ph-like fusions and other high-risk B-cell ALL.
Allogenic hematopoietic cell transplantation (alloHCT) is a well-established curative modality for adults with high-risk ALL; yet large data describing alloHCT outcomes in Philadelphia (Ph)-like ALL is lacking. We retrospectively analyzed archived DNA samples from consecutive adults with B-cell Ph-negative ALL who underwent alloHCT in complete remission (CR) (n= 127) at our center between 2006 and 2020. Identification of fusions associated with Ph-like were performed using accumulative results from RNAseq, conventional cytogenetics, FISH, and whole genome array studies. Fusions associated with Ph-like were detected in 56 (44%) patients, of whom 38 were carrying CRLF2r;  and the rest (n=18) were non-CRLF2r. Compared to other non-Ph-like (n=71), patients with fusions associated with Ph-like ALL were more frequently Hispanic (P=0.008), less frequently carried high-risk cytogenetics (P<0.001), and more likely to receive blinatumomab prior to HCT (P=0.019). With the median follow-up of 3.5 years, patients with Ph-like ALL fusions had comparable post-transplant outcomes compared to other B-cell ALL: 3-year relapse-free survival (RFS) [41% vs. 44%, P=0.36], overall survival (OS) [51% vs. 50%, P=0.59] and relapse [37% vs. 31%, P=0.47].  In multivariable analysis, age (P= 0.023), disease status at the time of transplant (P<0.001), and donor type (P=0.015) influenced OS. RFS (primary endpoint) was significantly influenced by disease status (P<0.001) and conditioning regimen intensity (P=0.014). Relapse rate was associated with disease status (P=0.028) and conditioning regimen intensity (P=0.028). In conclusion, our data suggest that alloHCT consolidation results in similarly favorable survival outcomes in adult patients with Ph-like fusions and other high-risk B-cell ALL.