Does blood transfusion predispose to cancer recurrence?

Retrospective studies of the relationship between perioperative blood transfusion and cancer recurrence are reviewed. Control for variables related to blood transfusion and potentially affecting disease recurrence--anemia, blood loss, duration of surgery, magnitude of the procedure, and stage of disease--was notably absent from the majority of studies. None of the negative studies had sufficient number of both transfused and untransfused patients to answer the question with statistical validity. No consensus emerged regarding the significance of blood transfusion for the cancer patient and no recommendations concerning the use of blood in patients with malignancies are justified on the basis of these studies.