Red blood cell transfusions and the survival in patients with cancer undergoing curative surgery: a systematic review and meta-analysis.

Allogenic red blood cell transfusions exert a potential detrimental effect on the survival when delivered to cancer patients undergoing surgery with curative intent. We performed a systematic review and meta-analysis to assess the association between perioperative allogenic red blood cell transfusions and risk of death as well as relapse after surgery for localized solid tumors. PubMed, the Cochrane Library, and EMBASE were searched from inception to March 2019 for studies reporting the outcome of patients receiving transfusions during radical surgery for non-metastatic cancer. Risk of death and relapse were pooled to provide an adjusted hazard ratio with a 95% confidence interval [hazard ratio (HR) (95% confidence interval {CI})]. Mortality and relapse associated with perioperative transfusion due to cancer surgery were evaluated among participants (n = 123 studies). Overall, RBC transfusions were associated with an increased risk of death [HR = 1.50 (95% CI 1.42-1.57), p < 0.01] and relapse [HR = 1.36 (95% CI 1.26-1.46), p < 0.01]. The survival was reduced even in cancer at early stages [HR = 1.45 (1.36-1.55), p < 0.01]. In cancer patients undergoing surgery, red blood cell transfusions reduced the survival and increased the risk of relapse. Transfusions based on patients' blood management policy should be performed by applying a more restrictive policy, and the planned preoperative administration of iron, if necessary, should be pursued.