The impact of pretransplant consolidation chemotherapy on clinical outcomes in adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia: a single-center retrospective study.

Acute lymphoblastic leukemia (ALL) is a malignant hematological disease that accounts for approximately 20% of adult leukemia. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently recognized as one of potentially curative treatments for ALL. Though pretransplant consolidation chemotherapy is generally considered essential, there is limited research on the optimal number of consolidation cycles, which leaves the ideal timing for transplant unclear. In this study, we retrospectively analyzed the clinical outcomes of 40 adult patients diagnosed with Philadelphia chromosome-negative ALL (Ph-negative ALL) who underwent allo-HSCT at our center between January 2014 and May 2025. Among these patients, eighteen received a single cycle of consolidation chemotherapy prior to transplant, while 22 underwent multiple cycles. No statistically significant differences were observed between the single and multiple consolidation groups in terms of overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR), or non-relapse mortality (NRM). The single consolidation group demonstrated 3-year OS rates of 57%, compared to 56% in the multiple consolidation group (p = 0.83). For DFS, the single consolidation group showed 3-year rates of 51%, versus 52% in the multiple group (p = 0.97). Regarding CIR, the single consolidation group had 3-year rates of 18%, compared to 28% in the multiple group (p = 0.48). In terms of NRM, the single consolidation group exhibited 3-year rates of 25%, versus 20% in the multiple group (p = 0.45). Our real-world findings indicate that a single cycle of pretransplant consolidation chemotherapy yields comparable clinical outcomes compared to multiple cycles. These results provide valuable evidence for potentially shortening the overall treatment duration for adult patients with Ph-negative ALL and may assist clinicians in determining the optimal timing for transplant.