TBI/Cy followed by auto-HSCT is a good choice next to allo-HSCT for patients with T-LBL/ALL.

The aim of this retrospective study was to evaluate the efficiency and safety of total body irradiation plus cyclophosphamide (TBI/Cy) followed by autogenetic hematopoietic stem cell transplantation (auto-HSCT) in T-LBL/ALL patients that cannot receive allogeneic hematopoietic stem cell transplant (allo-HSCT). Between 2013 and 2023, 24 patients received auto-HSCT following by TBI/Cy, 26 patients underwent allo-HSCT, all patients achieved completed hematopoietic reconstitution after HSCT. The progression free survival (PFS) and overall survival (OS) had no statistically significant differences between the two groups (P = 0.791, HR 1.127, 95%CI 0.456-2.785; P = 0.456, HR 0.685, 95%CI 0.256-1.828). Although the cumulative incidence of relapse was lower for patients who received allo-HSCT than auto-HSCT (P = 0.033, HR 3.707, 95%CI 1.188-11.570, 2-year relapse 11.5% vs. 33.3%), the incidence of non-relapse mortality (NRM) was higher than that in the auto-HSCT group (P = 0.014, HR 0.000, 95%CI -1.000 - -1.000, 2-year NRM, 23.1% vs. 0%). Trough Landmark analysis, the two groups showed a statistically significant difference in 3-year PFS and 4-year OS curves (Figure S2A&B, P = 0.039, HR 0.426, 95%CI 0.163-1.117; P = 0.014, HR 0.317, 95%CI 0.113-0.887). By COX analysis, poor baseline performance status (ECOG-PS ≥ 2) and CNS involvement were risk factors for PFS and OS. In conclusion, TBI/Cy followed by auto-HSCT is a good choice next to allo-HSCT for patients with T-LBL/ALL.