Miyao, Kotaro, Terakura, Seitaro, Kimura, Fumihiko, Konuma, Takaaki, Miyamura, Koichi, Yanada, Masamitsu, Kako, Shinichi, Morhishima, Satoko, Uchida, Naoyuki, Toya, Takashi, Ozawa, Yukiyasu, Fukuda, Takahiro, Tanaka, Masatsugu, Sawa, Masashi, Takada, Satoru, Yoshida, Shuro, Kimura, Takafumi, Ichinohe, Tatsuo, Atsuta, Yoshiko, and Kanda, Junya
• Hematopoietic stem cell transplantation with 7/8 HLA allele-matched unrelated bone marrow (7/8 UBMT) and umbilical cord blood (UCBT) make use of alternative donor sources for patients with acute leukemia who lack HLA- identical donors. • This report provides an updated comparison of 7/8 UBMT and UCBT in a Japanese nationwide cohort. • Disease risk- and conditioning intensity-based stratification was used for donor source selection. • A lower incidence of graft-versus-host disease was seen in UCBT recipients. • There was a survival advantage in 7/8 UBMT recipients with standard risk-disease who received a myeloablative conditioning regimen. The outcomes of 7/8 allele-matched unrelated bone marrow transplantation (7/8 UBMT) and umbilical cord blood transplantation (UCBT) have been improving. We retrospectively analyzed adults with acute leukemia who underwent their first 7/8 UBMT or UCBT in Japan. Between January 2008 and December 2017, a total of 4150 patients were recorded, including 488 who underwent 7/8 UBMT and 3662 who underwent UCBT. Only 32 patients with 7/8 UBMT had graft-versus-host-disease (GVHD) high-risk HLA mismatched pairs. Overall survival at 3 years was 54% for 7/8 the UBMT group and 46% for the UCBT group, a nonsignificant difference in multivariate analysis (hazard ratio [HR], 1.01; 95% confidence interval [CI],.88 to 1.17; P =.89). The 7/8 UBMT and UCBT groups showed a similar nonrelapse mortality rate (HR, 1.16; 95% CI,.96 to 1.45; P =.16) and relapse rate (HR,.85; 95% CI,.71 to 1.02; P =.08). However, the UCBT group had a lower risk of grade II-IV acute GVHD (HR,.76; 95% CI,.65 to.88; P <.001) and chronic GVHD (HR,.77; 95% CI,.66-.91; P =.002) compared with the 7/8 UBMT group. In stratified analyses combining disease risk with conditioning intensity, 7/8 UBMT showed superior overall survival to UCBT in standard risk and myeloablative conditioning (HR,.72; 95% CI,.56 to.93; P =.014). Both 7/8 UBMT and UCBT are appropriate alternative donor procedures. The stem cell source can be selected on the basis of disease risk, patient tolerability, or concerns regarding GVHD. [ABSTRACT FROM AUTHOR]