Validity of C-Reactive Protein as a Surrogate Marker for Infectious Complications After Surgery for Colorectal Cancer

This study aimed to establish a threshold of C-reactive protein (CRP) level for early detection of post-operative infectious complications after surgery for colorectal cancer. In this single-center, retrospective analysis, we studied the data of 178 patients who underwent surgery for colorectal cancer between January 2018 and February 2022. Elective surgery with curative intent was performed, and serum CRP levels were measured on five consecutive days after surgery. Receiver operating characteristic curves were utilized to assess the cutoff point of the CRP level with maximum predictive value, A total of 59 cases of early post-operative complications, including pneumonia, wound infection, intra-abdominal infection, and anastomotic leakage were evaluated. During the monitoring period, patients with complications had higher CRP level than those without complications. The cutoff points on the five post-operative days were estimated to be 6.50, 10.83, 11.44, 6.67, and 5.71 mg/dL, respectively, and they were correlated to the occurrence of infectious complications. Higher CRP levels were associated with greater blood loss during surgery (p = 0.003) and increased length of hospital stay (p < 0.001) than did lower CRP levels. C-reactive protein monitoring in the early post-operative period is a cost-effective test that can be easily performed to predict the occurrence of infectious complications. It may be helpful in improving surgical outcomes, shortening the length of hospital stay and appropriate antibiotic administration.