Early biochemical predictors of clinically relevant pancreatic fistula after distal pancreatectomy: a role for serum amylase and C-reactive protein.

Background: Recent evidence suggests that pancreatic inflammation plays a pivotal role in the occurrence of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy but few data are available for distal pancreatectomy (DP). The aim of this study was to evaluate the impact of early biochemical markers on the occurrence of CR-POPF after DP.

Methods: Clinical and laboratory data for 432 consecutive DP patients were reviewed. Serum amylase was evaluated on postoperative day (POD) 1, and drain fluid amylase (DFA) and C-reactive protein (CRP) were evaluated on POD 2 and 3. Receiver operator characteristic (ROC) curves were performed for all biochemical markers and an area under the curve (AUC) was computed. Multivariable regression analyses to identify the factors associated with CR-POPF and severe postoperative morbidity (Clavien-Dindo grade ≥ 3) were performed.

Results: At 90 days after surgery, CR-POPF occurred in 155 (36%) patients, severe complications in 66 (15%) patients. ROC curve analyses showed that DFA on POD2 had the largest AUC (0.753, p < 0.001), followed by serum amylase on POD 1 (0.651, p < 0.001), serum CRP on POD3 (0.644, p < 0.001), and CRP change between POD 2 and POD 3 (0.644, p < 0.001). Multivariable analysis identified male gender (OR 2.29, 95% CI 1.36-3.86; p = 0.002), DFA ≥ 1500 U/L on POD2 (OR 4.63, 95% CI 2.72-7.89; p < 0.001), serum amylase ≥ 100 U/L on POD 1 (OR 1.72, 95% CI 1.01-2.93; p = 0.046), and CRP increase by at least 25 mg/L on POD 3 compared to the previous day (OR 1.89, 95% CI 1.11-3.21; p = 0.019) as independent predictors of CR-POPF, yielding a valid regression model (AUC 0.765, 95% CI 0.714-0.816, p < 0.001).

Conclusions: Postoperative serum amylase and CRP trajectory represent useful early biochemical markers for CR-POPF in addition to DFA. Our findings suggest that these laboratory tests should be incorporated into clinical practice to aid postoperative patient and drain management.