The Application of Personalized Conditioning Regimens in Relapsed/Refractory Acute Myeloid Leukemia Receiving Allogeneic Hematopoietic Stem Cell Transplantation.

Abstract

Objective: To evaluate the efficacy and safety of personalized conditioning regimens in allogeneic hematopoietic stem cell transplantation (allo-HSCT) for the treatment of relapsed/ refractory acute myeloid leukemia (R/R AML).

Methods: A retrospective analysis of the clinical data of 14 R/R AML patients who underwent allo-HSCT with a personalized conditioning regimen was conducted.

Results: Among the 14 patients, there were 8 males and 6 females with a median age of 34.5 years (range 14-56). One patient received a transplant from a fully matched related donor, 2 from unrelated donors, and 12 from haploidentical donors. Prior to transplantation, all patients had a myeloblast percentage greater than 5% before transplantation, with a median myeloblast of 8.5 (6-88)%. Thirteen patients (92.86%) achieved morphologic leukemia-free state (MLFS) after conditioning. All patients achieved successful engraftment and hematopoietic recovery. The median time to neutrophil engraftment was 12 days (range 10-14), and the median time to platelet engraftment was 21.5 days (range 17-29). There was no obvious hepatorenal toxicity during the conditioning, and no mucositis more than grade 2 according to CTCAE 5.0 [1]. Bone marrow biopsies at +30 days post-transplant indicated remission in all cases. Two patients relapsed at 2 and 3 months post-transplant, with 2 dying after relapse. Additionally, 2 patients had CMV infections; 1 became negative after treatment, while the other remained positive and later died due to severe infection. As of the last follow-up, 11 out of 14 patients were alive (with marrow morphology and MRD Continuously negative).

Conclusion: Allo-HSCT with a personalized conditioning regimen can be considered a treatment option for patients with R/R AML.