Haploidentical vs sibling, unrelated, or cord blood hematopoietic cell transplantation for acute lymphoblastic leukemia
Authors: Wieduwilt Matthew J. , Metheny Leland , Zhang Mei-Jie , Wang Hai-Lin , Estrada-Merly Noel , Marks David I. , Al-Homsi A. Samer , Muffly Lori , Chao Nelson , Rizzieri David , Gale Robert Peter , Gadalla Shahinaz M. , Cairo Mitchell , Mussetti Alberto , Gore Steven , Bhatt Vijaya Raj , Patel Sagar S. , Michelis Fotios V. , Inamoto Yoshihiro , Badawy Sherif M. , Copelan Edward , Palmisiano Neil , Kharfan-Dabaja Mohamed A. , Lazarus Hillard M. , Ganguly Siddhartha , Bredeson Christopher , Diaz Perez Miguel Angel , Cassaday Ryan , Savani Bipin N. , Ballen Karen , Martino Rodrigo , Wirk Baldeep , Bacher Ulrike , Aljurf Mahmoud , Bashey Asad , Murthy Hemant S. , Yared Jean A. , Aldoss Ibrahim , Farhadfar Nosha , Liu Hongtao , Abdel-Azim Hisham , Waller Edmund K. , Solh Melhem , Seftel Matthew D. , van der Poel Marjolein , Grunwald Michael R. , Liesveld Jane L. , Kamble Rammurti T. , McGuirk Joseph , Munker Reinhold , Cahn Jean-Yves , Lee Jong Wook , Freytes César O. , Krem Maxwell M. , Winestone Lena E. , Gergis Usama , Nathan Sunita , Olsson Richard F. , Verdonck Leo F. , Sharma Akshay , Ringdén Olle , Friend Brian D. , Cerny Jan , Choe Hannah , Chhabra Saurabh , Nishihori Taiga , Seo Sachiko , George Biju , Baxter-Lowe Lee Ann , Hildebrandt Gerhard C. , de Lima Marcos , Litzow Mark , Kebriaei Partow , Hourigan Christopher S. , Abid Muhammad Bilal , Weisdorf Daniel J. , Saber Wael 
Published: September 2021

Abstract
The role of haploidentical hematopoietic cell transplantation (HCT) using posttransplant cyclophosphamide (PTCy) for acute lymphoblastic leukemia (ALL) is being defined. We performed a retrospective, multivariable analysis comparing outcomes of HCT approaches by donor for adults with ALL in remission. The primary objective was to compare overall survival (OS) among haploidentical HCTs using PTCy and HLA-matched sibling donor (MSD), 8/8 HLA-matched unrelated donor (MUD), 7 /8 HLA-MUD, or umbilical cord blood (UCB) HCT. Comparing haploidentical HCT to MSD HCT, we found that OS, leukemia-free survival (LFS), nonrelapse mortality (NRM), relapse, and acute graft-versus-host disease (aGVHD) were not different but chronic GVHD (cGVHD) was higher in MSD HCT. Compared with MUD HCT, OS, LFS, and relapse were not different, but MUD HCT had increased NRM (hazard ratio [HR], 1.42; P = .02), grade 3 to 4 aGVHD (HR, 1.59; P = .005), and cGVHD. Compared with 7/8 UD HCT, LFS and relapse were not different, but 7/8 UD HCT had worse OS (HR, 1.38; P = .01) and increased NRM (HR, 2.13; P ≤ .001), grade 3 to 4 aGVHD (HR, 1.86; P = .003), and cGVHD (HR, 1.72; P ≤ .001). Compared with UCB HCT, late OS, late LFS, relapse, and cGVHD were not different but UCB HCT had worse early OS (≤18 months; HR, 1.93; P &lt; .001), worse early LFS (HR, 1.40; P = .007) and increased incidences of NRM (HR, 2.08; P &lt; .001) and grade 3 to 4 aGVHD (HR, 1.97; P &lt; .001). Haploidentical HCT using PTCy showed no difference in survival but less GVHD compared with traditional MSD and MUD HCT and is the preferred alternative donor HCT option for adults with ALL in complete remission.