This meta-analysis covers 10 studies on a very relevant topic: blood salvage in cancer surgery, where every fourth unit of banked blood is used. The suggested conclusion that the procedure is without risk is speculative, since actually an improved outcome is expected from this autologous transfusion. Other evidence, e.g. the demonstration of viable tumor cells in the processed blood, is ignored, and analysis of the statistical power is lacking. The intended evaluation of the contraindications is impossible, since fatal risks like those of metastases have a lower incidence than that covered by the analyzed studies. Evidence other than from outcome studies have to be considered, as is common in tranfusion medicine. Two studies on the same patients with strikingly different results are included in the analysis without further discussion.

– Ernil Hansen