Prognostic impact of blood transfusions on disease-free survival in colorectal carcinoma.

Blood transfusions have been indicated as having an adverse effect on the prognosis of patients treated surgically for cancer. We carried out a randomized trial to investigate whether a predeposit autologous blood transfusion program improved prognosis in patients with colorectal cancer as compared to the current practice of allogeneic transfusion. This appeared not to be the case. However, the subgroup of untransfused patients had a significantly better disease-free survival compared with transfused patients; 73% and 59%, respectively (p = 0.001). We found that the risk of recurrence was significantly increased for patients transfused with allogeneic, or with autologous, or with both types of blood, compared with those patients who did not require transfusions; relative recurrence rates were 2.3 (p = 0.001), 1.8 (p = 0.044) and 2.5 (p = 0.009), respectively; these three rates did not differ significantly from each other. We conclude that it is not the blood transfusions themselves, but the circumstances that necessitate the transfusions that are the real determinants of prognosis.