[Clinical study of unrelated umbilical cord blood transplantation for 25 patients with hematological diseases].

This study was purposed to investigate the engraftment, graft-versus-host disease (GVHD), transplantation related mortality (TRM), relapse and survival in hematologic patients received unrelated umbilical cord blood transplantation (UCBT). A total of 25 patients with hematological disease underwent UCBT, including 8 pediatric and 17 young adult patients. Among them 3 cases received single unit of UCBT and 22 cases received double units of UCBT. For donor/recipients human leukocyte antigen (HLA) matching: HLA 6/6 loci matched in 9 cases, HLA 4-5/6 loci matched in 16 cases. There were 19 patients with hematologic malignancies, including 3 cases in the period of disease progression and 6 cases of non-hematologic malignancies. Conditioning regimens were TBI/Cy ± Flu ± ATG or BuCy ± Flu ± ATG for 21 patients and Cy+Flu+ATG for 4 patients. For prophylaxis of acute graft-versus-host disease (aGVHD) the regimen of cyclosporine (CsA) as dominant drug was used. The results showed that among 16 patients (80.0%) achieved engraftment, 20 patients survived for more than 42 d after transplantation. The cumulative neutrophil recovery rate on day 42 after transplant was 64.0%, with a median time of 17.0 d;the cumulative platelet recovery rate on day 100 after transplant was 60.0 %, with a median time of 35.0 d. The cumulative rate of grade II-IV and III-IV aGVHD after transplantation 100 d was 44.0% and 30.7%, respectively. Until the end of the follow-up, the cumulative rate of TRM was 54.3%. For all the patients, overall survival rate was 42.7%. Out of 17 evaluable patients with hematologic malignancies 7 cases (41.2%) survived to date, and only 1 case relapsed, so event-free survival rate was 35.3%. Out of 5 evaluable patients with non-hematologic malignancies, 4 patients survived and 2 patients were in stable engraftment state, 2 cases with autologous hematopoietic recovery. Among 3 cases of hematologic malignancies at advanced stage, only 1 case survived to date. It is concluded that HLA-4-6/6 loci matched UCBT is an effective option to treat hematological diseases. Double cord blood transplantation (dUCBT) can overcome the disadvantage of insufficient cells of single cord blood UCBT to treat overweight children and adult.