Usefulness of Serum Biomarkers in Predicting Anastomotic Leakage After Gastrectomy

Background/Objectives: Anastomotic leakage (AL) is one of the most concerning complications following gastrectomy. The aim of this study was to assess and compare the predictive accuracy of C-reactive protein (CRP), procalcitonin (PCT), the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), fibrinogen, and the mean platelet volume (MPV) in the early diagnosis of post-gastrectomy AL. Methods: A prospective bicentric observational study was conducted including all patients undergoing elective gastrectomy between August 2018 and December 2022. The performance of the selected biomarkers in predicting the existence of AL within the first 7 postoperative days (PODs) was assessed. Results: A total of 107 patients were included for analysis. The incidence of AL was 20.56%, and the median day of diagnosis was on POD5 (interquartile range 4-6). CRP, PCT, the NLR, the PLR, and fibrinogen showed significant associations with the presence of AL (from POD2 for CRP and fibrinogen and from POD3 for PCT, NLR, and PLR). CRP demonstrated a superior predictive accuracy on POD4, with a threshold value of 181.4 mg/L (NPV 99%; AUC 0.87, p < 0.001); PCT demonstrated a superior predictive accuracy on POD7, with a threshold value of 0.13 mu g/L (NPV 98%; AUC 0.84, p < 0.001); the NLR showed a superior predictive accuracy on POD6, with a threshold ratio of 6.77 (NPV 95%; AUC 0.86, p < 0.001); the PLR achieved a superior predictive accuracy on POD7, with a ratio of 234 (NPV 98%; AUC 0.71; p = 0.002); and fibrinogen demonstrated a superior predictive accuracy on POD5, with a threshold of 7.344 g/L (NPV 98%; AUC 0.74; p = 0.003). In the comparison of predictive accuracy, CPR, PCT, and the NLR were found to be superior to all other biomarkers. Conclusions: CRP, PCT, and the NLR are biomarkers with a sufficient predictive ability to clinically discard the presence of AL within the first postoperative week.