Myeloablative Haploidentical Transplant as an Alternative to Matched Sibling Transplant for Peripheral T-Cell Lymphomas

The number of HLA-haploidentical allogeneic hematopoietic stem-cell transplantation (Haplo-HSCT) is increasing. Comparative studies about Haplo-HSCT versus allo-HSCT with HLA-matched sibling donors (MSD-HSCT) have been tried in leukemias and B-cell lymphomas. Few studies were reported in Peripheral T-cell lymphomas (PTCLs). We performed a multicenter retrospective study about 52 patients with PTCLs undergoing Haplo-HSCT (n = 20) or MSD-HSCT (n = 32). All Haplo-HSCT recipients received antithymocyte globulin (ATG) based graft versus host disease (GVHD) prophylaxis. The median follow-up for all survivors was 38 months. The 100-day cumulative incidence of grade II to IV acute GVHD was similar (19% in the MSD-HSCT group versus 28% in the Haplo-HSCT group, P = 0.52). The 2-year cumulative incidence of chronic GVHD (limited and extensive) after Haplo-HSCT (30%) was also similar with that in the MSD-HSCT group (50%, P = 0.15). The 3-year relapse rates (33% vs 27%, P = 0.84) and non-relapse mortality (21% vs 22%, P = 0.78) did not differ between these two groups. There were also no differences in 3-year overall survival (OS) (48% vs 50%, P = 0.78) and progression-free survival (47% vs 51%, P = 0.95) between these two groups. On multivariate analysis, prognostic index for T-cell lymphoma (PIT) score (higher than 1: hazard ratio [HR], 4.0; P = 0.003) and disease status (stable or progression disease before HSCT: HR, 2.8; P = 0.03) were independent variables associated with worse OS. We concluded that ATG-based haplo-HSCT platform could work as an alternative to MSD-HSCT for patients with PTCLs.