Effect of pediatric- versus adult-type chemotherapy regimens on outcomes of allogeneic hematopoietic stem cell transplants for adult T-cell acute lymphoblastic leukemia in first complete remission

The optimal chemotherapy regimen pre-transplantation for adult T-cell acute lymphoblastic leukemia (T-ALL) patients remains unknown. Here, we compared the transplant outcomes in 127 subjects receiving pediatric- (N= 57) or adult-type (N= 70) regimens pre-transplant. The corresponding 3-year cumulative incidences of relapse (CIR) was 7% (95% CI: 3–11%) and 29% (95% CI: 23–35%; P= 0.02), leukemia-free survivals (LFS) was 86% (95% CI: 81–91%) and 57% (95% CI: 51–63%; P= 0.003), overall survivals (OS) was 88% (95% CI: 84–92%) and 58% (95% CI: 52–64%; P= 0.002), the 1-year NRM was 4% (95% CI: 1–7%) and 9% (95% CI: 4–14%; P= 0.40). Multivariate analysis showed that pediatric-type regimen was associated with lower CIR (Hazard Ratio [HR] = 0.31 [95% CI: 0.09–1.00]; P= 0.05), better LFS (HR = 0.34 [95% CI: 0.15–0.78]; P= 0.01) and OS (HR = 0.30 [95% CI: 0.13–0.72]; P= 0.01). Our results suggested that adult T-ALL patients undergoing allo-HSCT might benefit from pediatric-type chemotherapy.