Outcomes of allogeneic or autologous stem cell transplantation followed by maintenance chemotherapy in adult patient with B‐ALL in CR1 with no detectable minimal residual disease

Abstract Autologous haematopoietic stem cell transplantation (auto‐HSCT) as a treatment for B‐cell acute lymphoblastic leukaemia (B‐ALL) has been rigorously debated in recent years. We retrospectively analysed the outcomes of 355 adult patients with B‐ALL in first complete remission who had received auto‐HSCT or allogeneic HSCT (allo‐HSCT) in our centre. The treatment efficacy was evaluated from a model stratified on the risk classification and minimal residue disease (MRD) status after three chemotherapy cycles. Auto‐HSCT demonstrated comparable 3‐year overall survival (OS) (72.7% vs. 68.5%, p = 0.441) and leukaemia‐free survival rates (62.8% vs. 56.1%, p = 0.383) compared to allo‐HSCT for patients with negative MRD, while the advantage of lower non‐relapse mortality (1.5% vs. 25.1%, p < 0.001) was offset by a higher cumulative incidence of relapse (CIR) rates (35.7% vs. 18.9%, p = 0.018), especially in high‐risk patients. For patients at high risk and with positive MRD, there was a lower trend of 3‐year OS (50.0% vs. 66.0%, p = 0.078) and significantly higher CIR rates (71.4% vs. 39.1%, p = 0.018) in auto‐HSCT. However, no significant interaction was observed in the tests. In conclusion, auto‐HSCT appears to be an attractive treatment for patients with negative MRD after three chemotherapy cycles. For MRD‐positive patients, allo‐HSCT may be a more effective treatment.