-Author name in bold denotes the presenting author
-Asterisk * with author name denotes a Non-ASH member
Clinically Relevant Abstract denotes an abstract that is clinically relevant.

PhD Trainee denotes that this is a recommended PHD Trainee Session.

Ticketed Session denotes that this is a ticketed session.

4985 Prognostic Impact of Conditioning Intensity on Outcomes after Allogeneic Transplantation for MDS with Low BlastsClinically Relevant Abstract

Program: Oral and Poster Abstracts
Session: 732. Allogeneic Transplantation: Disease Response and Comparative Treatment Studies: Poster III
Hematology Disease Topics & Pathways:
Research, MDS, Biological therapies, Clinical Research, Chronic Myeloid Malignancies, Diseases, real-world evidence, Therapies, registries, Myeloid Malignancies, Transplantation
Monday, December 11, 2023, 6:00 PM-8:00 PM

Hidehiro Itonaga, MD, PhD1,2, Yasushi Miyazaki, MD PhD3, Machiko Fujioka, MD4*, Ken Ishiyama, MD, PhD5, Jun Aoki, MD, PhD6*, Noriko Doki, MD, PhD7, Tetsuya Nishida, MD, PhD8*, Takahiro Fukuda, MD, PhD9*, Naoyuki Uchida, MD, PhD10, Yasunori Ueda, MD, PhD11, Yasufumi Uehara12*, Yuta Katayama, MD, PhD13, Makoto Onizuka, MD, PhD14, Tatsuo Ichinohe, M.D.Ph.D.15 and Yoshiko Atsuta, MD, PhD16*

1Transfusion and Cell Therapy Unit, Nagasaki University Hospital, Nagasaki, Japan
2Transfusion and Cell Therapy Unit, Nagasaki University Hospital, Nagasaki city, NSK, Japan
3Nagasaki University, Nagasaki, Japan
4Department of Hematology, Sasebo City General Hospital, Sasebo, NSK, JPN
5Department of Hematology, National Center for Global Health and Medicine, Tokyo, Japan
6Department of Hematology, Kanto Rosai Hospital, Kawasaki, Japan
7Hematology Division, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, Tokyo, Japan
8Department of Hematology, Japanese Red Cross Aichi Medical Center Nagoya Daiichi Hospital, Nagoya, Japan
9Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan
10Department of Hematology, Toranomon Hospital, Tokyo, Japan
11Department of Hematology/Oncology, Transfusion and Hemapheresis Center, Kurashiki Central Hospital, Kurashiki, Japan
12Department of Hematology, Kitakyushu City Hospital Organization, Kitakyushu Municipal Medical Center, Kitakyushu, Japan
13Department of Hematology, Hiroshima Red Cross Hospital & Atomic-bomb Survivors Hospital, Hiroshima, Japan
14Department of Hematology/Oncology, Tokai University School of Medicine, Isehara, Japan
15Research Institute For Radiation Biology and Medicine, Hiroshima, Japan
16Japanese Data Center For Hematopoietic Cell Transplantation, Nagakute, Japan


Allogeneic hematopoietic stem cell transplantation (allo-HSCT) provides curative outcomes in patients with myelodysplastic syndromes (MDS). The blast percentage in MDS is one of the important factors to utilize allo-HSCT, and the other disease-related factors, such as transfusion dependency and chromosomal risk, are crucial to consider whether patients harboring MDS with less than 5% of marrow blasts (MDS-Lo) undergo to allo-HSCT. However, the prognostic impacts of conditioning intensity in MDS-Lo patients are still unclear. We here conducted a nationwide retrospective study to clarify the prognostic factor and investigate the optimal conditioning intensity for MDS-Lo.


In this study, patients diagnosed as the other than refractory anemia with excess blasts (RAEB)-1 and -2 according to the WHO classification (marrow blasts <5% and peripheral blood blasts <1%) were considered to be MDS-Lo. The clinical data of 1,229 de novo MDS-Lo patients (i) who had stayed MDS-Lo from diagnosis to transplantation and (ii) who underwent their initial allo-HSCT between January 2001 and December 2020 were collected from the Transplant Registry Unified Management Program of the Japan Society for Hematopoietic Cell Transplantation. Cox proportional hazards regression models were used to evaluate variables potentially affecting overall survival (OS), chronic graft-versus-host disease (GVHD)-free survival (CRFS), and GVHD- and relapse-free survival (GRFS). Fine and Gray proportional hazards models were used to evaluate variables potentially affecting cumulative incidences of relapse (CIR) and non-relapse mortality (NRM), using cumulative incidence curves to accommodate competing events.


In a total of 1,229 patients, 651, 397, and 181 patients received myeloablative conditioning (MAC), reduced-intensity conditioning (RIC), and non-myeloablative conditioning (NMAC) groups, respectively. The estimated 3-year OS rates were 63.3%, 61.0%, and 69.7% in MAC, RIC, and NMAC groups, respectively; the estimated 3-year CRFS rates were 41.1%, 43.9%, and 47.2% in MAC, RIC, and NMAC groups, respectively; the estimated 3-year GRFS rates were 27.5%, 33.4%, and 35.4% in MAC, RIC, and NMAC groups, respectively; the estimated 3-year CIR were 11.9%, 14.2%, and 16.0% in MAC, RIC, and NMAC groups, respectively; and the estimated 3-year NRM were 29.8%, 31.0%, and 24.7% in MAC, RIC, and NMAC groups, respectively.

The multivariate analyses revealed four factors affecting lower OS: older recipient’s age (Hazard ratio (HR) [95% confidential interval], 1.70 [1.28-2.24]; P<0.001 for 40-59 years)(HR, 2.32 [1.71-3.15]; P<0.001 for 60 years or older), performance status 2-4 at HSCT (HR, 1.84 [1.32-2.57]; P<0.001), the history of infection before HSCT (HR, 2.12 [1.55-2.89]; P<0.001), and high number of red blood cell (RBC) transfusion before HSCT (HR, 1.65 [1.35-2.02]; P<0.001). These factors also negatively affected CRFS, GRFS, and NRM. In addition, poor cytogenetic risk group was associated with worse OS (HR, 1.66 [1.32-2.09]; P<0.001), CRFS (HR, 1.48 [1.22-1.80]; P<0.001), and GRFS (HR, 1.36 [1.14-1.64]; P=0.001) but not CIR. There was no significant difference of OS, CRFS, GRFS, CIR, and NRM in either RIC or NMAC group compared to MAC group.

We next performed the subgroups analysis based on the prognostic factors. The subgroup analysis for the comparison between MAC and RIC regimens showed the better OS of MAC regimen among patients with low number of RBC transfusion (HR, 1.33 [1.01-1,75]; P=0.039). The subgroup analysis for the comparison between RIC and NMAC regimens revealed the better OS of NAMC regimen among patients aged <40 years (HR, 0.43 [0.19-0.96]; P=0.038), no history of infection (HR, 0.67 [0.50-0.91]; P=0.009), and good cytogenetic risk (HR, 0.54 [0.38-0.83]; P=0.004).


This study showed the prognostic factors on the post-transplant outcomes among MDS-Lo patients, and no significant difference of conditioning intensity in the entire population. Furthermore, we found the factors (the number of RBC transfusion, patient’s age, the history of infection, and cytogenetic risk) potentially affecting the selection of conditioning intensity. These findings would improve the management for transplant candidates with MDS-Lo.

Disclosures: Miyazaki: Dainippon-Sumitomo: Honoraria; Novartis: Honoraria; Nipponshinnyaku: Honoraria; Chugai: Honoraria; Otsuka: Honoraria; Astellas: Honoraria; Kyowa-Kirin: Honoraria; Celgene: Honoraria. Doki: Novartis Pharma K.K.: Honoraria; Janssen Pharmaceutical K.K.: Honoraria. Ichinohe: Takeda Pharmaceutical Co.: Honoraria; Repertoite Genesis Inc.: Research Funding; Kyowa Kirin: Research Funding; Nippon Kayaku Co.: Honoraria; Novartis: Honoraria; Chugai: Honoraria, Research Funding; Nippon Shinyaku Co.: Honoraria, Research Funding; Wakunaga Pharmaceutical Co., Ltd.: Research Funding; Sumitomo Pharma Co: Honoraria, Research Funding; AsahiKasei Pharma Co.: Honoraria, Research Funding; Abbvie Co.: Honoraria, Research Funding; Ono Pharmaceutical Co.: Honoraria. Atsuta: Meiji Seika Pharma Co, Ltd.: Honoraria; JCR Pharmaceuticals Co., Ltd.: Consultancy; Otsuka Pharmaceutical Co., Ltd: Speakers Bureau; Novartis Pharma KK: Speakers Bureau; CHUGAI PHARMACEUTICAL CO., LTD.: Speakers Bureau.

*signifies non-member of ASH