Clinical Analysis Of Umbilical Cord Blood Transplantation And Haploidentical Hematopoietic Stem Cell Transplantation

Objective:To explore the clinical efficacy and prognosis of umbilical cord blood transplantation(UCBT)and haploidentical hematopoietic stem cell transplantation(Haplo-HSCT)in patients with hematological malignancies.Methods:The clinical data of patients with hematological malignancies who underwent UCBT and Haplo-HSCT in our center from July 2013 to October 2019 were retrospectively analyzed.A total of 49 patients were included in the study,including 25in the UCBT group and 24 in the Haplo-HSCT group.In the UCBT group,there were8 cases of single umbilical cord blood transplantation(s UCBT)and 17 cases of double umbilical cord blood transplantation(d UCBT).The analyses of hematopoietic reconstruction,the incidence of acute graft-versus-host disease(a GVHD)and chronic graft-versus-host disease(c GVHD),overall survival(OS),leukemia-free survival(LFS),relapse and non-relapse mortality(NRM),immune reconstruction were performed in order to comprehensively evaluate clinical efficacy and prognosis.Results:1.UCBT1.1 Overall analysis of UCBT:The median age of patients in the UCBT group was21(7～59)years.The median total nucleated cells(TNC)of cord blood transfusion was4.15(2.29～7.24)×10~7/kg and the median number of CD34+cells was 1.32(0.22～7.90)×10~5/kg.The median time of neutrophil and platelet engraftment was 23(12～38)days and 45(25～144)days,respectively.16(64%)patients developed a GVHD,of which 9(36%)were grade III-IV;5(20%)patients developed c GVHD.A total of 12(48%)patients died and 2(8%)relapsed;the OS and LFS rate at 2 years was 52%and48%,respectively.1.2 Comparison of s UCBT and d UCBT:The median time of neutrophil engraftment was 26(12～37)days in s UCBT and 23(18～38)days in d UCBT(P=0.807).The median time of platelet engraftment was 42(25～50)days and 58.5(33～144)days(P=0.018),indicating that platelet engraftment was significantly faster in s UCBT.The incidence of a GVHD,especially severe a GVHD,was significantly higher in the d UCBT group than in the s UCBT group(p<0.01).There was no statistical difference in c GVHD between the two groups.The 2-year OS rate was 37.5%in the s UCBT group versus 58.8%in the d UCBT group(P=0.435),and the 2-year LFS rate was 25%and58.8%(P=0.136),respectively.2.Haplo-HSCT:The median age of patients in the Haplo-HSCT group was 31(13～65)years.The median number of mononuclear cells of peripheral blood transfusion was 9.72(2.22～36.59)×10~8/kg and the median number of CD34+cells was 3.82(1.29～17.92)×10~6/kg.The median time of neutrophil and platelet engraftment was 13(9～26)days and 16.5(11～93)days,respectively.5(20.8%)patients developed a GVHD,of which 2(8.3%)were grade III-IV;2(8.3%)patients had localized c GVHD.A total of 8(33.3%)patients died,of which 4(16.7%)died of relapse and 4(16.7%)were non-relapse mortality;the 2-year OS and LFS rates were both 62.1%.3.Comparison of UCBT and Haplo-HSCT:The time of neutrophil and platelet engraftment was significantly different(P<0.001 and P=0.001)in two groups.The hematopoietic reconstruction was significantly faster in the Haplo-HSCT group than in the the UCBT group.The recovery of CD3+T cells and CD8+T cells was significantly delayed in the UCBT group at 30 days after transplantation compared with the Haplo-HSCT group(both P=0.001).The immune reconstruction was faster in the Haplo-HSCT group than in the UCBT group.The incidence of a GVHD was 64%and 20.8%(P=0.019),and the incidence of c GVHD was 20%and 8.3%,respectively,in the UCBT and Haplo-HSCT group(P=0.417).The relapse rate was 8%and 16.7%(P=0.417),and the non-relapse mortality rates were 44%and 16.7%(P=0.062).The 2-year OS rate was 52.0%in the UCBT group versus 62.1%in the Haplo-HSCT group(P=0.342),and the 2-year LFS rate was 48%and 62.1%,respectively(P=0.208).Conclusion:Umbilical cord blood transplantation is effective;the incidence and severity of a GVHD in d UCBT patients are higher than s UCBT.Haplo-HSCT is equivalent to UCBT in therapeutic effect.The reconstruction of hematopoietic and immune in Haplo-HSCT with PTcy regimen is faster than that in UCBT,and the incidence of a GVHD is lower than that in UCBT patients.Therefore,for patients without HLA-identical donor,cord blood and haploidentical grafts are undoubtedly suitable donor alternatives.