Blood Transfusions and Local Tumor Recurrence in Colorectal Cancer Evidence of a Noncausal Relationship

Abstract

OBJECTIVE: The authors analyzed the effect of blood transfusions on the pattern of colorectal cancer recurrence. BACKGROUND: Retrospective studies suggest that blood transfusions are associated with a poor prognosis in patients who undergo operations for colorectal malignancies. In a previously published, randomized trial, it was investigated whether autologous blood transfusions could overcome this putative detrimental effect. However, this did not appear to be the case. METHODS: In the current study, the authors analyzed the patterns of recurrence in 420 patients who underwent curative operations for colorectal cancer. RESULTS: Patients who did not require transfusions (N = 143) had significantly better disease-free survival than those who did need transfusions (N = 277); percentages at 4 years were 73% and 59%, respectively (p = 0.001). No difference was found between both groups in comparing cumulative percentages of patients having metastases; percentages at 4 years were 25% in the group that did not undergo transfusion and 27% in the transfused group. The percentage of cases having local recurrence, however, was significantly increased (p = 0.0006) in the transfused group as compared with the group that did not undergo transfusion; percentages at 4 years were 20% and 3%, respectively. The groups of patients receiving only allogeneic, only autologous, or both types of transfusions all had a significantly higher incidence of local recurrence than the patients who did not receive transfusions, but no differences were found between these three groups. CONCLUSIONS: These findings suggest that the association between blood transfusions and prognosis in colorectal cancer is a result of the circumstances that necessitate transfusions, leading to the development of local recurrences, but not of distant metastase