Myelodysplastic syndrome (MDS) is a complex hematological malignancy, often presenting with myelofibrosis (MF) in 10% to 20% of cases. Although MF is recognized as an independent risk factor for MDS prognosis, it is not consistently included in prognostic scoring systems like IPSS-R and IPSS-M. Previous research indicates that moderate to severe MF in MDS is linked to poor outcomes, including decreased survival and poor response to azacitidine. However, the impact of MF on the prognosis of patients with MDS undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains controversial.

In a recent retrospective study, researchers analyzed 153 patients with primary MDS who underwent allo-HSCT between March 2016 and December 2022. The study aimed to evaluate the clinical characteristics, outcomes, and impact of MF on these patients’ prognoses. The authors excluded patients with MDS who transformed to acute myeloid leukemia (AML) before transplantation. Conditioning regimens varied between myeloablative (MAC) and reduced intensity conditioning (RIC), with standard graftversus host disease (GVHD) prophylaxis protocols.

Results published online in the Journal of Translational Medicine showed no significant differences in overall survival (OS) and progression free survival (PFS) between patients with moderate to severe MF (MF-2/3) and those with mild or no MF (MF-0/1). Specifically, the 2-year OS rates were 76.6% for MF-0/1 and 75.4% for MF-2/3, while the 2-year PFS rates were 73.7% for MF-0/1 and 71.4% for MF-2/3. These findings suggest that MF-2/3 does not adversely affect survival post-allo-HSCT.

Univariate and multivariate analyses identified major/bidirectional ABO blood type in compatibility as an independent risk factor for both OS and PFS. In contrast, MF did not significantly impact engraftment, GVHD incidence, relapse, or non-relapse mortality (NRM). Subgroup analysis of MDS with increased blasts (MDS-IB) also indicated no significant differences in 2-year OS and PFS between MF-0/1 and MF-2/3 cohorts.

The study underscores the importance of achieving complete remission (CR) before transplantation, particularly in MDS-IB patients, and suggests that the MAC regimen may offer superior PFS compared to RIC. The impact of ABO incompatibility and the potential benefits of CR and MAC regimens highlight critical considerations for optimizing allo-HSCT outcomes in MDS patients.

Overall, the authors concluded moderate to severe MF does not significantly affect post-transplant survival in patients with MDS. Major/bidirectional ABO incompatibility and pretransplant disease status are crucial factors influencing prognosis.