Haploidentical Hematopoietic Stem Cell Transplant Compared with Matched Sibling and Unrelated Transplants in Adults with Philadelphia-Negative Acute Lymphoblastic Leukemia in First Complete Remission

Matched-sibling donor (MSD) and matched unrelated donors (MUD) hematopoietic stem-cell transplantation (HSCT) have been recommended for the adults with acute lymphoblastic leukemia (ALL) in first complete remission (CR1). However, it is not defined for this portion of patients whether HLA haploidentical donor (HID) transplants can achieve equivalent outcomes compared to MSD and MUD transplants. From 2009 to 2014, 379 adult patients with Ph-negative ALL in CR1 underwent HID HSCT (n = 159), or MSD HSCT (n = 135), or MUD HSCT (n = 85). Among HID, MSD and MUD transplants, the 100-day incidences of acute graft-versus-host disease (aGVHD) Grade Ⅲ-IV were 11.0%, 8.4% and 10.6% respectively (P>0.05), and 2-year chronic GVHD (cGVHD) were 38.9%, 28.5% and 35.6% respectively ( P>0.05 ). At 5 years, the incidences of relapse were 19.0%, 24.0% and 23.4% in HID, MSD and MUD transplants respectively (P>0.05). The 5-year transplant related mortality (TRM) of HID was higher than MSD transplants (16.5% vs 10.9%, P = 0.032), and no difference compared with MUD transplants (16.5% vs 18.1%, P > 0.05). However, the 5-year overall survival (OS), disease-free survival (DFS) did not differ among HID, MSD and MUD transplants (OS 70.9%, 72.0%, 65.4% respectively, P > 0.05; DFS 67.3%, 66.0%, 62.0%, respectively, P > 0.05).

Our results indicate that outcomes of adult patients with Ph-negative ALL in CR1 from HID transplants are comparable to MSD and MUD transplants.