Reduced intensity conditioning increases risk of severe cGVHD: identification of risk factors for cGVHD in a multicenter setting.

Chronic graft-versus-host disease (cGVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Aim is to identify risk factors for the development of cGVHD in a multicenter setting. Patients transplanted between 2000 and 2006 were analyzed (n = 820). Donors were HLA-identical siblings (57%), matched unrelated donors (30%), and HLA-A, B or DR antigen mismatched (13%). Reduced intensity conditioning (RIC) was given to 65% of patients. Overall incidence of cGVHD was 46% for patients surviving more than 100 days after HSCT (n = 747). Older patient age [HR 1.15, p < 0.001], prior acute GVHD [1.30, p = 0.024], and RIC [1.36, p = 0.028] increased overall cGVHD. In addition, RIC [4.85, p < 0.001], prior aGVHD [2.14, p = 0.001] and female donor to male recipient [1.80, p = 0.008] increased the risk of severe cGVHD. ATG had a protective effect for both overall [0.41, p < 0.001] and severe cGVHD [0.20, p < 0.001]. Relapse-free survival (RFS) was impaired in patients with severe cGVHD. RIC, prior aGVHD, and female-to-male donation increase the risk of severe cGVHD. ATG reduces the risk of all grades of cGVHD without hampering RFS. GVHD prophylaxis may be tailored according to the risk profile of patients.

Evidence for a graft-versus-leukemia effect after allogeneic peripheral blood stem cell transplantation with reduced-intensity conditioning in acute myelogenous leukemia and myelodysplastic syndromes.

We report the results of a prospective study of a reduced-intensity conditioning (RIC) regimen followed by allogeneic peripheral blood stem cell transplantation (PBSCT) from an HLA-identical sibling in 37 patients with acute myeloid leukemia (AML; n = 17) or myelodysplastic syndrome (MDS; n = 20). The median age was 57 years, and 22 (59%) were beyond the early phase of their disease. The incidence of grade II to IV acute graft-versus-host disease (GVHD) was 19% (5% grade III-IV), and the 1-year incidence of chronic extensive GVHD was 46%. With a median follow-up of 297 days (355 days in 24 survivors), the 1-year probability of transplant-related mortality was 5%, and the 1-year progression-free survival was 66%. The 1-year incidence of disease progression in patients with and without GVHD was 13% (95% CI, 4%-34%) and 58% (95% CI, 36%-96%), respectively (P =.008). These results suggest that a graft-versus-leukemia effect plays a crucial role in reducing the risk of relapse after a RIC allograft in AML and MDS.