Background. The present study investigated relationships between perioperative blood transfusion, postoperative systemic inflammatory response, and outcomes following surgery for colorectal cancer. Methods. Data were recorded for patients (n = 544) undergoing potentially curative, elective surgery for colorectal cancer at a single center between 2012 and 2017. Transfusion history was obtained retrospectively from electronic records. Associations between blood transfusion, postoperative C-reactive protein (CRP), albumin, hemoglobin, complications, cancer-specific survival and overall survival (OS) were assessed using propensity score matching (n =116). Results. Of 544 patients, the majority were male (n =294, 54%), over 65 years of age (n =350, 64%), and with colonic (n =347, 64%) node-negative disease (n =353, 65%). Eighty-six patients (16%) required perioperative blood transfusion. In the unmatched cohort, blood transfusion was associated with higher median postoperative day (POD) 3 CRP {143 [interquartile range (IQR) 96-221 mg/L] vs. 120 (IQR 72-188 mg/L); p = 0.004}, lower median POD 3 albumin [24 (IQR 20-26 g/L) vs. 27 (IQR 24-30 g/L); p \ 0.001], more postoperative complications [odds ratio (OR) 3.28, 95% confidence interval (CI) 2.03-5.29] and poorer OS [hazard ratio (HR) 3.18, 95% CI 2.08-4.84]. In the propensity score matched cohort, blood transfusion was similarly associated with higher median POD 3 CRP [130 (IQR 93-196 mg/L) vs. 113 (IQR 66-173 mg/L); p = 0.046], lower median POD 3 albumin [24 (IQR 20-26 g/L) vs. 26 (IQR 24-30 g/L); p \ 0.001], more postoperative complications (OR 2.91, 95% CI 1.36-6.20) and poorer OS (HR 2.38, 95% CI 0.99-5.73). Conclusions. Perioperative blood transfusion was associated with postoperative inflammation, complications, and poorer survival in patients undergoing colorectal cancer surgery, with and without propensity score techniques. A significant proportion of patients undergoing surgery for colorectal cancer require allogeneic blood transfusion in the perioperative period. 1 Such transfusions are associated with infective postoperative complications and anastomotic leak. 2,3 They are also associated with disease recurrence, 3,4 and this effect is even greater in the presence of infective complications. 5 Therefore, it has long been hypothesized that allogeneic blood transfusion might impair the host adaptive immune response to both pathogens and circulating or micrometastatic tumor cells. 6 There is increasing evidence that an exaggerated postoperative systemic inflammatory response following surgery for colorectal cancer is associated with postoperative complications and long-term survival. 7 Furthermore, there is some observational evidence that modulation of this response can improve both short-8 , and long-term outcomes. 9 It may be that perioperative blood transfusion and postoperative complications have a negative impact on oncologic outcomes via a common pathway, the systemic inflammatory response. 10

Background Systemic inflammation, even at low levels, can greatly interfere with measures of iron status, making diagnosis of iron deficiency difficult. The objective of the present study was to create linear regression correction equations to adjust serum ferritin and iron concentrations based on measurements of the acute-phase proteins C-reactive protein (CRP) and albumin. Methods Data from a cohort (1) of patients (n = 7226) in primary and secondary care who had serum ferritin, iron, CRP, and albumin measured at the same time point were examined. Linear regression coefficients were calculated for CRP and albumin with serum iron and ferritin as the outcome variables. Patients with ferritin <15 µg/L or serum iron <10 µmol/L were categorized as iron deficient. The equation was then applied to a cohort (2) of patients with colorectal cancer who had ferritin and iron measured preoperatively ( n = 356). Results In cohort 1 there was a significant difference in the proportions of patients with serum ferritin <15 µg/L and serum iron <10 µmol/L, respectively, when the unadjusted (7% and 55%), adjusted based on CRP alone (13% and 26%), adjusted based on albumin alone (11% and 37%), and adjusted based on both CRP and albumin (24% and 15%) values were compared (both P < 0.001). In cohort 2 there was a significant difference in the proportions of patients with serum ferritin <15 µg/L and serum iron <10 µmol/L, respectively, when the unadjusted (28% and 66%), adjusted based on CRP alone (39% and 57%), adjusted based on albumin alone (39% and 59%), and adjusted based on both CRP and albumin (46% and 44%) values were compared (P < 0.001 and P < 0.004). Conclusions In both cohorts the greatest increase in the proportion of patients meeting definitions of iron deficiency was found when adjustment was made for both CRP and albumin together. Even low levels of inflammation had a significant effect on serum iron and ferritin values.

Quantitative data on red cell measures of iron status and their relation to the magnitude of the systemic inflammatory response and survival in patients with colorectal cancer.

No abstract