[Induction of aGVHD after allogeneic hematopoietic stem cell transplantation for refractory or relapsed acute...

Patients with refractory or relapsed acute leukemia after allogeneic hematopoietic stem cell transplantation had a poor prognosis with high death rate due to relapse or transplant-related mortality (TRM). The purpose of this paper was to clarify the role of inducing acute graft-versus-host disease (aGVHD) during transplantation in preventing relapse.

Thirty adult patients with refractory or relapsed leukemia were acute lymphoblastic leukemia (n=16), acute myelogenous leukemia (n=10), and acute mixed leukemia (n=4). They were in first complete remission (n=4), second complete remission (n=9), partly remission (n=12), and non-response (n=5) at the time of transplantation. Patients underwent allogeneic peripheral blood stem cell transplantation (allo-PBSCT) from HLA-identical siblings (n=21), mismatched siblings donors (n=3), and allogeneic bone marrow transplantation (n=5) or allo-PBSCT (n=1) from unrelated HLA matched donors. All patients received myeloablative regimens for eliminating residual leukemic cell. For aGVHD prophylaxis the patients with HLA-identical siblings donors received cyclosporine (CSA) alone, and the patients with mismatched siblings or unrelated donors received CSA, methotrexate, mycophenolate mofetil, and low-dose ATG. For inducing aGVHD after transplantation, patients were scheduled to be quickly reduced the maintenance dose of CSA at 20% to 30% off every week or treated with pre-emptive donor leukocyte infusion if there was no appearance of aGVHD at +30 days to 60 days after transplantation.

After a median follow-up of 18.1 months, there were 24/30 (80%) patients developed aGVHD (grade 3 or 4 had 4/30, 13.3%). There were 11/19 (57.9%) patients developed chronic GVHD (cGVHD), with 3/19 (15.8%) had extensive cGVHD. Eighteen patients are alive with disease-free survival (18/30, 60%) and 12 patients have died of relapse (5/28, 17.9%) and TRM (7/30, 23.3%).

Induction of aGVHD after transplantation is feasible and effective to prevent relapse in patients with refractory or relapsed acute leukemia.