Abstract: Objective To investigate relationships between perioperative blood transfusion and postoperative inflammatory complications in patients with colorectal cancer. Methods The patients who underwent colorectal cancer surgery and were pathologically diagnosed with malignant tumors between February 2019 and June 2021 were collected. The perioperative blood transfusion, hematological parameters, modified Glasgow Prognostic Score (mGPS), operation mode, operation time, tumor size, tumor location, TNM staging, hospital length of stay and postoperative inflammation were statistically analyzed.Results A total of 643 patients met the inclusion and exclusion criteria, including 201 cases of preoperative anemia (31.3%), 442 cases of non-anemia (68.7%), and 156 cases of perioperative blood transfusion (24.3%), 487 cases (75.7%) without blood transfusion, and inflammatory complications occurred in 115 cases (17.9%). After propensity score matching, the perioperative transfusion group (81 cases) and non-transfusion group (81 cases) were compared and analyzed. The results showed that the incidence of inflammatory complications in the perioperative transfusion group was significantly higher than that in the non-transfusion group (32.1% and 17.3%, respectively, P=0.029), The median hospital length of stay was longer (23 and 20.5 days, respectively, P=0.008). Univariate logistic regression analysis showed that perioperative blood transfusion was an independent risk factor for postoperative inflammatory complications (OR 2.262, 95% CI 1.078~4.747, P=0.031).Conclusion Perioperative blood transfusion is associated with postoperative inflammatory complications in patients undergoing colorectal cancer surgery.

Key words: Colorectal cancer, Transfusion, Inflammatory complication, Anemia