Predictive Value of Dynamic Peri-Transplantation MRD Assessed By MFC Either Alone or in Combination with Other Variables for Outcomes of Patients with T-Cell Acute Lymphoblastic Leukemia

Summary We performed a retrospective analysis to investigate dynamic peri-hematopoietic stem cell transplantation (HSCT) minimal/measurable residual disease (MRD) on outcomes in patients with T-cell acute lymphoblastic leukemia (T-ALL). A total of 271 patients were enrolled and classified into three groups: unchanged negative MRD pre- and post-HSCT group (group A), post-MRD non-increase group (group B), and post-MRD increase group (group C). The patients in group B and group C experienced a higher cumulative incidence of relapse (CIR) (42% vs. 71% vs. 16%, P <0.001) and lower leukemia-free survival (LFS) (46% vs. 21% vs. 70%, P <0.001) and overall survival (OS) (50% vs. 28% vs. 72%, P <0.001) than in group A, but there was no significant difference in non-relapse mortality (NRM) among three groups (14% vs. 12% vs. 8%, P =0.752). Multivariate analysis showed that dynamic peri-HSCT MRD was associated with CIR (HR=2.392, 95% CI, 1.816–3.151, P <0.001), LFS (HR=1.964, 95% CI, 1.546–2.496, P <0.001) and OS (HR=1.731, 95% CI, 1.348–2.222, P <0.001). We also established a risk scoring system based on dynamic peri-HSCT MRD combined with remission status pre-HSCT and onset of chronic graft- versus -host disease (GVHD). This risk scoring system could better distinguish CIR (c=0.730) than that for pre-HSCT MRD (c=0.562), post-HSCT MRD (c=0.616) and pre- and post-MRD dynamics (c=0.648). Our results confirm the outcome predictive value of dynamic peri-HSCT MRD either alone or in combination with other variables for patients with T-ALL.