[Prophylactic Use of Tyrosine Kinase Inhibitors after Allogeneic Hematopoietic Stem Cell Transplantation for Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia].

The introduction of tyrosine kinase inhibitors (TKIs) has greatly improved outcomes for patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) undergoing allogeneic hematopoietic stem cell transplantation (HSCT). However, patients with measurable residual disease (MRD) positivity at the time of HSCT show a high relapse rate, making post-HSCT TKI administration a promising strategy. However, the indications, administration methods, and optimal duration of TKI therapy remain unclear. Retrospective studies from outside Japan have suggested that prophylactic TKIs may reduce relapse risk and improve survival. Although first- and second-generation TKIs demonstrate potential efficacy, tolerability issues persist. Ponatinib, a third-generation TKI, has shown promising results, especially in high-risk patients and those with the T315I mutation, although clinical evidence is limited due to small study populations. Although TKI administration after HSCT has generally demonstrated potential benefits, prospective trials are needed to provide robust evidence.