Trend of C-Reactive protein after colorectal surgery may increase predictive value of anastomotic leak: a prospective analysis

Early diagnosis of anastomotic leak (AL) after colorectal surgery is essential to reduce mortality and overall survival. C-reactive protein (CRP) is among the factors most significantly associated with infection and AL. Analysis of trend in CRP levels could be crucial in increasing its predictive value. We performed a prospective evaluation on a cohort of patients undergoing colorectal resection for cancer, comparing CRP values on the first postoperative days to assess delta CRP in relation to identification of AL. Our prospective evaluation considered cases of elective colorectal surgery for cancer, enrolled by two high-volume centers from January 2021 to June 2024. We considered 2 groups: leakage (L group) and non-leakage (NL group). Evaluation of CRP levels on POD 1 and 3 was recorded, analyzing linear difference (delta CRP). Patients with suspicion of AL underwent postoperative imaging. Final analysis was conducted on 320 patients. Among these, 13 (4.1%) experienced an AL. CRP levels on POD1 and POD3, and delta CRP variables demonstrated AUC values of 0.692, 0.902, and 0.969, respectively, indicating that delta CRP is the most predictive measure compared to individual CRP values. Delta CRP reported a specificity of 0.964 and a sensitivity of 0.923. Our data confirmed that high NPV of postoperative CRP trend was able, already on POD3, to rule out anastomotic complications. CRP trend between POD1 and POD3 seems to increase the sensitivity and specificity of this biochemical marker, which should be confirmed by larger cohorts, considering this a pilot study.