[Indications for allogeneic stem cell transplantation in Philadelphia chromosome-positive acute lymphoblastic leukemia].

Allogeneic hematopoietic stem cell transplantation (allo-SCT) in first complete remission (CR1) has been the standard treatment for Philadelphia chromosome-positive acute lymphoblastic leukemia. However, the introduction of imatinib, a first-generation tyrosine kinase inhibitor (TKI), dramatically improved outcomes. The subsequent development of next-generation TKIs like dasatinib and ponatinib, as well as the antibody therapy blinatumomab, has further diversified treatment strategies. There is an increasing shift toward avoiding allo-SCT in pediatric patients, both in Japan and internationally. For elderly patients ineligible for allo-SCT, chemotherapy-free regimens combining TKIs and blinatumomab show promise for improving outcomes. Moreover, international studies suggest that young adults may also be able to avoid allo-SCT in CR1. In contrast, current data in Japan are insufficient to support the avoidance of allo-SCT in CR1, and caution is needed when applying findings from overseas. Future efforts should focus on establishing personalized treatment approaches, including risk-stratified transplantation eligibility.