Perioperative Blood Transfusion Impairs Overall Survival Following Radical Resection for Colorectal Cancer: A Propensity Score-Matched Analysis

Background/Objectives: Perioperative blood transfusion (BTF) remains controversial regarding its impact on oncological outcomes in colorectal cancer (CRC). This study aimed to evaluate the association between BTF, transfusion volume, and long-term prognosis in CRC patients undergoing radical resection. Methods: We conducted a retrospective cohort study of 1777 CRC patients who underwent radical surgery at the Fourth Hospital of Hebei Medical University between December 2007 and April 2015. Propensity score matching (PSM) was applied to minimize selection bias between BTF and non-BTF groups. Logistic regression identified factors associated with BTF receipt. Cox proportional hazards models assessed the association between BTF and 5-year overall survival (OS). X-tile analysis determined optimal cut-off values for transfusion volume stratification. Results: Among 1777 patients, 729 (41.02%) received BTF. After PSM, 524 well-matched pairs showed balanced baseline characteristics. Intestinal obstruction was independently associated with BTF requirement (p < 0.001). The BTF group demonstrated significantly inferior 1-, 3-, and 5-year OS compared with non-BTF groups in both overall and PSM cohorts (all p < 0.01). Multivariate Cox analysis identified BTF as an independent adverse prognostic factor (HR = 1.44, 95% CI 1.09–1.89, p = 0.01). X-tile analysis stratified patients into non-BTF, small-volume (≤4 units), and massive-volume (>4 units) groups. Massive-volume transfusion showed the poorest survival outcomes (p < 0.0001) and was independently associated with worse OS (HR = 1.61, 95% CI 1.18–2.20, p = 0.003). Supplementary analyses indicated that no independent association was observed between survival outcomes and either preoperative inflammatory markers or the specific timing and type of transfusion. Conclusions: BTF, particularly when exceeding 4 units, independently predicts inferior long-term survival in CRC patients following radical resection. These findings support the implementation of restrictive transfusion strategies in perioperative CRC management. Given its retrospective observational design, this study shows an association but does not establish causality, and our findings should be interpreted in light of the aforementioned limitations.