Perioperative blood transfusions, with or without allogeneic leucocytes, relate to survival, not to cancer recurrence

Background: Perioperative blood transfusions are reported to be related to cancer recurrence and reduced survival. Different underlying mechanisms have been proposed, and allogeneic leucocytes in transfused blood have been suggested to contribute to this phenomenon. Methods: Packed red cells without buffy coat (PC group) were compared with filtered, leucoreduced, red cells (LD group) in a randomized trial of 697 patients with colorectal carcinoma. Five-year survival and cancer recurrence rates were determined, with special emphasis on the location of recurrence. Results: The intention-to-treat analysis showed a survival rate of 63.6 per cent in the PC group and 65.3 per cent in the LD group (P = 0.69), with recurrence rates of 27.8 and 27.9 per cent respectively. The observational analysis showed a significant difference in survival between transfused and non-transfused patients (59.6 versus 72.9 per cent; P < 0.001). The difference in cancer recurrence rate between transfused and non-transfused patients was not statistically significant (29.8 versus 24.3 per cent; P = 0.13). Local recurrences were more frequent in transfused than non-transfused patients (11.9 versus 7.6 per cent; P = 0.09). Conclusion: Leucocyte depletion of perioperative transfused blood has no effect on long-term survival and/or cancer recurrence. Perioperative blood transfusions are associated with impaired survival, but not with cancer recurrence. The slight increase in local recurrence rate in transfused patients appears to be related to complicated, in particular rectal, surgery.