Neutrophil to Lymphocyte Ratio and C-Reactive Protein as Two Predictive Tools of Anastomotic Leak in Colorectal Cancer Open Surgery

Abstract

Purpose: To assess the prognostic value of postoperative C-reactive protein (CRP) and neutrophil to lymphocyte ratio (NLR) in the development of anastomotic leak (AL) in patients after surgery for colorectal cancer (CRC).

Methods: Patients operated on for CRC between 2010 and 2014 were enrolled into the study. The sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPVs) were calculated for the CRP and NLR measured on the 4th postoperative day (POD).

Results: Among 724 patients, AL was diagnosed in 33 (4.6%). The accuracy of CRP in the detection of AL using area under curve was 0.83 with the optimal cut-off value of 180 mg/L, sensitivity 75%, specificity 91%, PPV 52% and NPV 87%. Also, NLR on POD4 was higher in the AL group: 9.03 ± 4.13 vs. 4.45 ± 2.25; p = 0.0012; sensitivity 69%, specificity 78%, PPV 49%, NPV 88% at cut-off point of 6.5. Moreover, CRP and NLR on POD4 were significantly higher in patients who died in the postoperative period: 239 ± 24 mg/L vs. 199 ± 41 mg/L; p = 0.034 and 10.71 ± 2.08 vs. 8.65 ± 4.67; p = 0.029, respectively).

Conclusions: CRP and NLR on POD4 possess the ability to predict the development of AL and postoperative mortality after CRC operation. Based on our results, high NPV might be indicative of patients with low risk of AL in their postoperative period.

Keywords: Anastomotic leak; C-reactive protein; Colorectal cancer; Neutrophil to lymphocyte ratio; Predictive value.