Perioperative blood transfusion and resection of colorectal cancer liver metastases: outcomes in routine clinical practice

Background: Prior work has shown associations between blood transfusion (BT) and inferior outcomes during resection for colorectal cancer liver metastases (CRLM). Herein, we describe short and long-term outcomes relating to perioperative BT in routine clinical practice. Methods: All CRLM resections in Ontario, Canada from 2002 to 2009 were identified using the Ontario Cancer Registry. Log-binomial regression and Cox regression were used to explore factors associated with receipt of BT and the association of BT with 5-year cancer specific (CSS) and overall survival (OS), respectively. Results: The study included 1310 patients; 31% (403/1310) had perioperative BT. Transfused patients had longer median length of stay (9 vs. 7 days, p < 0.001), higher 90-day mortality (9% vs. 1%, p < 0.001), greater 90-day readmission (28% vs. 16%, p < 0.001), and inferior 5-year CSS (41% vs. 48%, p =< 0.001) and OS (38% vs. 47%, p < 0.001). Transfusion was independently associated with inferior CSS (HR = 1.35, 95% CI: 1.11-1.63) and OS (HR = 1.30, 95% CI: 1.10-1.53), however, excluding 90-day postoperative deaths showed these associations were no longer significant. Conclusion: Perioperative BT is common in patients undergoing resection of CRLM. While transfusion is associated with greater morbidity, mortality, and inferior survival, after excluding early postoperative deaths, BT does not appear to be independently associated with CSS or OS.