Conditioning intensity in myelodysplastic patients aged ≥ 50 years undergoing allogeneic hematopoietic cell transplantation (allo-HCT): a study on behalf of the chronic malignancies working party of the EBMT

Abstract

<p>Reduced intensity conditioning (RIC) is usually used for patients with myelodysplastic syndrome (MDS) undergoing allogeneic hematopoietic cell transplantation (allo-HCT), particularly in the elderly or those with comorbidities. The impact of conditioning intensity on patients' outcome remains controversial with clinicians' subjective opinion/ experience remaining a major guide in choosing the intensity. Here, we compare RIC versus MAC in a large EBMT retrospective study in MDS patients aged >= 50 years undergoing allo-HCT between 2014 and 2018. Among the 1393 included patients, 922 (66%) were males, and the median age at transplant was 62.8 (50.0-77.9) years. The majority of patients (<i>n</i> = 884; 64.3%) had MDS with excess blasts. IPSS-R recorded was very low/low (<i>n</i> = 598, 43%), intermediate (<i>n</i> = 352, 25%), and high/very high (n = 443, 32%). Karnofsky index was >= 90 in 916 (69.3%) patients, and HCT-CI >= 3 in 292(27.3%) patients. A RIC regimen was used in 1053 (75.5%) patients. Median follow-up was 27.9 months (IQR: 26.4-30.6). Both uni- and multi-variable analyses did not show any significant association between conditioning intensity and outcomes. This study highlights a lack of association between RIC/MAC regimens and outcomes in allo-HCT MDS patients. Our results support the recently published systematic review and meta-analysis, where evidence for using one conditioning regimen over another remains weak.<br></p>