Comparison of outcomes between haploidentical and matched related donors for chronic myelomonocytic leukemia: A multicenter real-world study.

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative strategy for patients with chronic myelomonocytic leukemia (CMML). However, few reports have investigated the outcomes of patients receiving haploidentical HSCT. To this end, we included 117 patients with haploidentical donors (HID) and 75 patients with matched related donors (MRD) from 28 centers across China to explore the prognostic impact of different transplantation modalities. We found no significant difference between these two groups in terms of event-free survival (EFS, p = .211), overall survival (OS, p = .503), cumulative incidence of relapse (CIR, p = .076) or non-relapse mortality (NRM, p = .794). The predominance of peripheral blood (PB) graft source over bone marrow and PB since 2020 may have contributed to the worse outcomes in the MRD group. Moreover, CMML-specific prognostic scoring system (CPSS) lower-risk patients benefited more from the HID modality with superior EFS (p = .006). Multivariate analysis indicated that advanced age (p = .013), anemia at diagnosis (p = .010), and donor relationship (parent-to-child, p = .013) were independently associated with worse EFS in the HID group. Our data suggested that HID was comparable to MRD in CMML. However, under certain conditions, such as CPSS lower-risk ones, HID was preferred.