Outcome and prognostic factors among patients who underwent a second transplantation for disease relapse post the first allogeneic cell transplantation

Outcomes in patients with acute lymphoblastic leukemia who underwent second allogeneic hematopoietic cell transplantation for relapse after first transplantation

Outcomes in patients with acute lymphoblastic leukemia (ALL) who experience relapse after allogeneic hematopoietic cell transplantation (HCT) are unsatisfactory. This study aimed to evaluate the outcomes of patients with ALL who underwent second HCT (HCT2) for relapse after first HCT. It was a single-center retrospective study including adult patients with ALL who underwent HCT2 between 1991 and 2020. The cohort was stratified according to the transplant year, and included 39 patients with a median age of 29 years. A more recent transplant year was associated with achievement of complete remission (CR) and use of reduced-intensity conditioning (RIC), compared with an earlier transplant year. The overall survival (OS) rate and 2-year cumulative incidence of non-relapse mortality (recent vs. earlier) were 55% vs. 8% (P < 0.001) and 26% vs. 75% (P < 0.001), respectively. In multivariate analysis, non-CR (vs. CR; HR 3.6, 95% CI 1.2-11.3, P = 0.025) and myeloablative conditioning (vs. RIC; HR 3.5, 95% CI 1.3-9.4, P = 0.011) were negative prognostic factors for OS. Outcomes of the recent cohort from real-world data are promising, and achieving CR and using the RIC regimen at HCT2 may be an important therapeutic strategy.

A case series of patients treated with inotuzumab ozogamicin for acute lymphoblastic leukemia relapsed after allogeneic hematopoietic cell transplantation

This single-center retrospective study was performed in consecutive patients with acute lymphoblastic leukemia who relapsed after allogeneic hematopoietic cell transplantation (HCT) and received salvage therapy using inotuzumab ozogamicin (InO). Ten patients (median age: 27 years) treated between June 2018 and July 2020 who met the eligibility criteria were included in this study. Nine patients received InO in one cycle and seven of these patients achieved complete hematological remission after salvage chemotherapy including InO. Negative minimal residual disease was confirmed in all four evaluable patients. Eight patients were successfully bridged to the subsequent HCT. After HCT, veno-occlusive disease (VOD) developed in three patients, and caused the death of one. No patient received maintenance therapy. At present, five patients are disease-free and alive, and the overall and progression-free survival rates at 1 year were 60% and 40%, respectively. High rates of disease remission and bridging to HCT with comprehensive treatments including InO may have contributed to favorable outcomes. However, further investigation is needed to reduce post-HCT complications including VOD.

Outcomes of second hematopoietic stem cell transplantation using reduced-intensity conditioning in an outpatient setting

Relapse and graft failure after autologous (auto) or allogeneic (allo) hematopoietic stem cell transplantation (HSCT) are serious and frequently fatal events. A second HSCT can be a life-saving alternative, however, information on the results of such intervention in an outpatient setting is limited. Outpatient second hematoprogenitors transplant after reduced-intensity conditioning (RIC) at a single academic center was analyzed. Twenty-seven consecutive adults who received an allo-HSCT after an initial auto- or allo-HSCT from 2006 to 2019 were included. Data were compared using the χ² -test. Survival analysis using Kaplan-Meier and Cox proportional hazard models was performed; cumulative incidence estimation of transplant-related mortality (TRM) was assessed. Hodgkin lymphoma was the most frequent diagnosis for the group with a first auto-HSCT with 5/12 (41.7%) cases, and acute myeloid leukemia for those with a first allo-HSCT with 6/15 (40%). One-year overall survival and disease-free survival (DFS) was 66.7% (95% CI 27.2-88.2) and 59% (95% CI 16-86) for 12 patients with a first auto-HSCT; and for 15 patients with a first allo-HSCT, it was 43.3% (95% CI 17.9-66.5) and 36% (95% CI 13.2-59.9), respectively. Eight (29.6%) patients died of TRM and the cumulative incidence of TRM at 1 year was 22% (95% CI 8.6-39.27). Chronic graft-versus-host disease and late (>10 months) second transplantation were protective factors for longer survival. Neutropenic fever was more common in the group with a first allo-HSCT (p = 0.01). In conclusion, outpatient second allo-HSCT using RIC after auto- or allografting failure or relapse is feasible and offers a reasonable alternative for patients with severe life-threatening hematological diseases.