Hepatic veno-occlusive disease/sinusoidal obstruction syndrome after hematopoietic stem cell transplantation for thalassemia major: incidence, management, and outcome

Hepatic veno-occlusive disease or sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). In the present prospective study, we aimed to investigate the incidence, management, and outcome of VOD/SOS in patients with thalassemia major (TM) who received allo-HSCT. VOD/SOS was diagnosed and classified based on the modified Seattle criteria. The prophylactic regimen for VOD/SOS was a combination treatment of dalteparin and lipo-PGE1. VOD/SOS was managed through an approach consisting of adequate supportive measures, short-term withdrawal of calcineurin inhibitors (CNIs), and the use of methylprednisolone and basiliximab for graft-versus-host disease prophylaxis. VOD/SOS was found in 54 of 521 patients (10.4%) at a median time of 12 days after allo-HSCT. The cumulative incidence of all-grade and moderate VOD/SOS was 10.4% and 4.2%, respectively. Among the 54 VOD/SOS patients, no patient developed severe grade and died from VOD/SOS. Besides, the cumulative incidence of transplant-related mortality on day 100 for patients with or without VOD/SOS was 0% vs. 4.0% (P = 0.187), respectively, and the 3-year overall survival rates were 94.3% vs. 93.2% (P = 0.707), respectively. Collectively, we concluded that appropriate symptomatic therapy and short-term withdrawal of CNIs safely mitigated the mortality of VOD/SOS in TM patients who underwent allo-HSCT.