C‐reactive protein (CRP) trajectory as a predictor of anastomotic leakage after rectal cancer resection: A multicentre cohort study

Aim This study aimed to identify whether CRP‐trajectory measurement, including increase in CRP‐level of 50 mg/l per day, is an accurate predictor of anastomotic leakage (AL) in patients undergoing resection for rectal cancer. Methods A prospective multicentre database was used. CRP was recorded on the first three postoperative days. Sensitivity, specificity, positive and negative predictive values, and area under the receiver operator characteristic (ROC) curve were used to analyse performances of CRP‐trajectory measurements between postoperative day (POD) 1–2, 2–3, 1–3 and between any two days. Results A total of 271 patients were included in the study. AL was observed in 12.5% (34/271). Increase in CRP‐level of 50 mg/l between POD 1–2 had a negative predictive value of 0.92, specificity of 0.71 and sensitivity of 0.57. Changes in CRP‐levels between POD 2–3 were associated with a negative predictive value, specificity and sensitivity of 0.89, 0.93 and 0.26, respectively. Changes in CRP‐levels between POD 1–3 showed a negative predictive value of 0.94, specificity of 0.76 and sensitivity of 0.65. In addition, 50 mg/l changes between any two days showed a negative predictive value of 0.92, specificity of 0.66 and sensitivity of 0.62. The area under the ROC curve for all CRP‐trajectory measurements ranged from 0.593–0.700. Conclusion The present study showed that CRP‐trajectory between postoperative days lacks predictive value to singularly rule out AL. Early and safe discharge in patients undergoing rectal surgery for adenocarcinoma cannot be guaranteed based on this parameter. High negative predictive values are mainly caused by the relatively low prevalence of AL.