Perioperative allogeneic blood transfusion, the related cytokine response and long-term survival after potentially curative resection of colorectal cancer.
It is still debated whether perioperative blood transfusion alters the incidence of disease recurrence or otherwise affects the prognosis after curative resection of malignant tumours. We conducted a prospective observational study of patients with colorectal cancer to provide data on the effect of blood transfusion and the related perioperative cytokine response on long-term prognosis. Perioperative blood samples were obtained from 117 patients with colorectal cancer undergoing potentially curative resection. Factors associated with perioperative blood transfusion were assessed, and their relationship with early postoperative systemic responses of tumour growth factors and long-term prognosis were evaluated. Independent factors associated with perioperative blood transfusion were preoperative anaemia, operative blood loss and the development of postoperative infectious complication. The patients receiving transfusions were subdivided according to the independent factors. Group A comprised 19 patients who received blood transfusions because of preoperative anaemia and Group B comprised 16 patients who received blood transfusions because of excessive operative blood loss. Group B patients showed exaggerated postoperative systemic induction of interleukin (IL)-6 and IL-6-triggered tumour growth factors, such as hepatocyte growth factor and vascular cell adhesion molecule-1. Intraoperative blood transfusion under intense surgical stress was associated with poor prognosis, whereas preoperative blood transfusion for correcting anaemia or intraoperative blood transfusion under less invasive surgery was not associated with survival. Multivariate analysis using the Cox proportional hazards method showed that a significant independent risk was demonstrated for blood transfusion, T stage, lymph-node metastasis and perioperative peak levels of IL-6. Blood transfusion and intense surgical stress might synergistically affect the long-term prognosis after curative resection of colorectal cancer. Postoperative exaggerated systemic inductions of IL-6 may indicate the critical situation that could lead to disease recurrence.