There is still no consensus on whether drain fluid amylase (DFA) level, C-reactive protein (CRP) level, or complex scores predict clinically relevant postoperative pancreatic fistula (CR-POPF). The aim of this study is to determine the accuracy of simple biochemical parameters (leucocytes, neutrophils, lymphocytes, Neutrophil to Lymphocytes Ratio (NLR), at postoperative days 1 and 3) to exclude the diagnosis of CR-POPF.

From January 1, 2012 to December 31, 2020, consecutive patients underwent PD performed at Institut Paoli-Calmettes for various pathologies. Data were entered prospectively into a clinical database (NCT02871336).

The cohort was split into 3 groups:

• a training cohort ;
• an internal validation cohort (Paoli Calmettes institute);
• an external validation cohort (Rennes Pontchaillou Hospital).

Inclusion Criteria:

• Patients who underwent pancreatoduodenectomy

Exclusion Criteria:

• Total pancreatectomy
• Enucleation

3 cohorts, which were as follows: the set of 451 patients was randomly sampled following a ratio 2:1 into a training (n=301) and a validation (n=150) cohort to respectively determine and validate the accuracy, best timing, and cut-off for the surrogate markers, then validated in an external cohort (n=197).