Incidence, risk factors and outcomes of sinusoidal obstruction syndrome after haploidentical allogeneic stem cell transplantation.

Hepatic sinusoidal obstruction syndrome (SOS) has been rarely studied after haploidentical donor (HID) allogeneic hematopoietic stem cell transplantation (allo-HSCT). We performed a retrospective multicentre study on patients with SOS after allo-HSCT in China. The incidence, risk factors, and outcomes were compared between HID HSCT and matched related donor (MRD) HSCT. SOS developed in 0.4% of patients (HIDs: 0.4%, MRDs: 0.5%, p = 0.952) at a median time of 21.50 days (range, 1-55) after allo-HSCT (HIDs: 24 days, MRDs: 20 days, p = 0.316). For patients diagnosed with SOS, the 2-year cumulative incidence of relapse was 22.7% and 22.4% in patients receiving HID and MRD transplantation, respectively (p = 0.584). Overall survival (OS) at 2 year was 10.4% and 38.5% in the two groups (p = 0.113). The transplant-related mortality (TRM) at 100 days was 60.9% in the HID group and 38.5% in the MRD group (p = 0.178). According to the multivariate analyses, significant independent risk factors for the occurrence of SOS were delayed platelet engraftment (p = 0.007) and advanced disease status at the time of HSCT (p = 0.009). The outcomes of SOS after HID HSCT are similar to those after MRD HSCT.