Second hematopoietic stem cell transplantation as salvage therapy for relapsed acute myeloid leukemia/myelodysplastic syndromes after a first transplantation

Abstract

Second allogeneic hematopoietic stem-cell transplantation (HSCT2) is a therapeutic option for patients with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) relapsing after a first transplant (HSCT1). However, patients allocated to HSCT2 may be a selected group with better prognosis and the added efficacy of HSCT2 is not well established. We retrospectively analyzed 407 consecutive patients with relapsed AML/MDS after HSCT1. Sixty-two patients had HSCT2 (15%) and 345 did not. The 2-year cumulative incidence rates of non-relapse mortality and relapse after HSCT2 were 26% (95% confidence interval [95% CI]: 17-39%) and 50% (95% CI: 39-65%), respectively. The 5-year overall survival rates were 25% (95% CI: 14-36%) and 7% (95% CI: 4-10%) in the HSCT2 and no-HSCT2 groups, respectively. Multivariate analysis identified female gender (hazard ratio [HR]=0.31, P=0.001), short remission duration after HSCT1 (HR=2.31, P=0.05), acute graft-versus-host disease after HSCT1 (HR=2.27, P=0.035), HSCT2 from a haplo-identical donor (HR=13.4, P=0.001) or matched unrelated donor (HR=4.53, P=0.007) and relapse after HSCT1 in earlier years (HR=2.46, P=0.02) as factors predicting overall survival after HSCT2. Multivariate analysis of all patients including HSCT2 as a timedependent variable identified relapse within 6 months after HSCT1 (HR=2.32, P<0.001), acute graft-versus-host disease before relapse (HR=1.47, P=0.005), myeloablative conditioning in HSCT1 (HR=0.67, P=0.011), female gender (HR=0.71, P=0.007), relapse in earlier years (HR=1.33, P=0.031) and not having HSCT2 (HR=1.66, P=0.010) as predictive of overall survival after relapse. In conclusion, HSCT2 is associated with longer survival compared to non-transplant treatments and may be the preferred approach in a subset of patients with relapsed AML/MDS after HSCT1.

Figure 1.

Figure 1. Outcomes after second allogeneic hematopoietic stem cell transplantation. (A) Non-relapse mortality. (B) Relapse. (C) Overall survival. HSCT2: second hematopoietic stem cell transplantation.

Figure 2.

Overall survival afer relapse. (A) Overall survival in 345 patients not given a second hematopoietic stem cell transplant (HSCT2) compared with overall survival after HSCT2 in 62 recipients (calculated from the day of the second transplant). (B) Landmark analysis at 60 days after relapse according to whether patients did or did not have a HSCT2.