Long-term outcomes of HLA-haploidentical stem cell transplantation based on an FBCA conditioning regimen compared with those of HLA-identical sibling stem cell transplantation for haematologic malignancies.

A comparison was conducted of 213 patients with haematologic malignancies who underwent HLA-identical sibling (n=108) or HLA-haploidentical (n=105) haematopoietic cell transplantation (haplo-HCT) at our centre. The conditioning regimen included fludarabine, busulphan, cyclophosphamide and antilymphocyte globulin (ATG) (FBCA). The total dose of ATG differed between identical and haploidentical groups (3.75 mg/kg versus 12.5 mg/kg). The cumulative incidences of grade II-IV acute GvHD in the identical and haploidentical groups were 20.4% and 21.9% (P=0.73), and 2-year cumulative incidences of chronic GvHD were 36.4% and 24.1% (P=0.17), respectively. The 3-year probabilities of non-relapse mortality for identical and haploidentical groups were 20.5% and 34.9% (P=0.048), and for relapse were 22.2% and 21.0% (P=0.85), respectively. The 3-year overall survivals in the identical and haploidentical groups were 62.6% and 52.6% (P=0.054), whereas the 3-year disease-free survivals were 54.7% and 43.1% (P=0.14), respectively. In the multivariate analysis, patients in the high-risk group exhibited reduced survival, and the higher dose of mononuclear or CD34+ cells resulted in an increase in the likelihood of survival. In conclusion, haplo-HCT based on an FBCA conditioning regimen could achieve nearly comparable outcomes to HLA-identical sibling HCT.