Hodgkin lymphoma patients who received haploidentical (HAPLO) allogeneic hematopoietic cell transplantation after a nonmyeloablative regimen and posttransplantation cyclophosphamide had outcomes similar to those of patients who had conventional transplants, in a retrospective analysis of 709 adult patients in the European Society for Blood and Marrow Transplantation database.
In addition, patients who underwent HAPLO had a lower incidence of extensive chronic graft-versus host disease (cGVHD) compared with HLA-matched unrelated donor (MUD) transplantation and higher cGVHD-free/relapse-free survival compared with HLA-matched sibling donor (SIB) transplantation.
“Use of HAPLO donors may allow patients to proceed more rapidly to transplantation, avoiding the time needed to complete a formal MUD search and arrange for graft collection at a remote center,” wrote Carmen Martinez, MD, of the Institute of Hematology and Oncology, Hospital Clinic, Barcelona. The study was published online in the Journal of Clinical Oncology. Conventional donors are unavailable for a significant proportion of Hodgkin lymphoma patients.
Recommendations from the European Society for Blood and Marrow Transplantation consider alloHCT to be the standard treatment option for eligible patients with Hodgkin lymphoma who have relapsed after undergoing autologous hematopoietic cell transplantation and SIB or MUD. For the retrospective study, outcomes were compared for 338 patients who had SIB transplants, 273 patients who had MUD transplants, and 98 patients who received HAPLO transplants after a nonmyeloablative regimen and posttransplantation cyclophosphamide (PTCy) as GVHD prophylaxis.
The rate of grade II-IV acute GVHD after HAPLO was higher than after SIB (33% vs. 18%; P = .003), and was comparable to the rate with MUD (30%). The rates of grade III-IV acute GVHD were similar for all three cohorts (HAPLO, 9%; SIB, 6%; and MUD, 9%).
At 1 year, the cumulative rate of chronic GVHD was 26% after HAPLO and 25% after SIB; it was significantly higher at 41% after MUD (P = .017).
The cumulative incidence of nonrelapse mortality at 1 year was 17% with HAPLO, 13% with SIB, and significantly higher at 21% with MUD (P = .003). At 2 years, the cumulative incidence of relapse or progression was 39%, 49%, and 32%, respectively. The difference was significantly higher for SIB than HAPLO (P = .047) and MUD (P = .001).
There were no significant differences in 2-year overall survival, but MUD transplant recipients had lower overall survival (62%; 95% CI, 56 to 68; P = .039) compared with SIB transplant recipients.
“Whether HAPLO transplantation is the first choice instead of MUD transplantation and whether it can eventually substitute SIB transplantation in specific subgroups of patients must be assessed within the context of a randomized prospective clinical trial,” wrote Dr. Martinez and colleagues.