Clinical outcomes and relapse predictors after allo-HSCT in pediatric T-ALL/T-LBL

Results from a single-center, retrospective analysis, assessing clinical outcomes and relapse predictors after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/T-LBL), were published in Transplantation and Cellular Therapy by Klimentova et al. The study included 135 children (T-ALL, n = 128; T-LBL, n = 7) transplanted between 2012 and 2024. Endpoints included cumulative incidence of relapse/progression (CIR), non-relapse mortality (NRM), event-free survival (EFS), overall survival (OS), and cumulative incidence of acute and chronic graft-versus-host disease (GvHD). Particular focus was placed on identifying and evaluating clinical and disease-specific risk factors that could affect transplant outcomes.

Key data: The 5-year cumulative incidence of NRM was 7.6% (95% confidence interval [CI], 4.2–13.8); the leading cause was infectious complications. The 5-year CIR was 25.9% (95% CI, 12.7–57.3); all patients who relapsed after HSCT died, with a median survival of 55 days following relapse. The rates of 5-year EFS and OS were 63.2% (95% CI, 55.0–71.4) and 65.7% (95% CI, 57.5–73.9), respectively. In multivariable analysis, active disease at HSCT was the strongest predictor of relapse (hazard ratio [HR], 5.65; 95% CI, 2.75–11.90; p < 0.0001), while central nervous system (CNS) involvement before HSCT was also associated with increased relapse risk (HR, 2.09; 95% CI, 1.00–4.36; p = 0.049).

Key learning: The predominant factor influencing outcomes in pediatric patients with T-ALL/T-LBL was the disease status at the time of HSCT, emphasizing the importance of optimizing pre-HSCT disease control.