Use of prophylactic anticoagulation and the risk of hepatic veno-occlusive disease in patients undergoing hematopoietic stem cell transplantation: a systematic review and meta-analysis.

Hepatic veno-occlusive disease is a serious regimen-related toxicity in patients undergoing hematopoietic stem cell transplantation. We performed a systematic review and meta-analysis of the literature on the effect of anticoagulation in preventing veno-occlusive disease. Several databases and online journals were searched for randomized controlled trials and cohort studies. Twelve studies (2782 patients) were eligible. Anticoagulation prophylaxis was associated with a statistically nonsignificant decrease in risk of veno-occlusive disease (pooled relative risk (RR), 0.90; 95% confidence interval (CI), 0.62-1.29). Results of one of three randomized controlled trials may have been affected by delayed introduction of anticoagulation. A second trial enrolled patients who received conventional chemoradiotherapy for early-stage disease (RR, 0.18; 95% CI, 0.04-0.78). The third trial was a pilot study with a small sample size (RR, 0.74; 95% CI, 0.53-1.04). Significant heterogeneity and methodologic weaknesses preclude drawing a meaningful conclusion from the pooled analysis. Despite some limitations, results of two of three eligible randomized controlled trials suggest that prophylactic anticoagulation may help prevent veno-occlusive disease. However, a large randomized controlled trial is needed for confirmation. Additionally, in future studies, owing to the wide spectrum of severity of veno-occlusive disease, outcomes such as 100-day mortality should strongly be considered.