Few reports have validated the clinical postoperative pancreatic fistula (PF) after distal pancreatectomy. The study intended to validate the predictability for clinical PF of drain amylase and lipase and to find out more appropriate postoperative day (POD) for diagnostic criterion of PF.

A total of 154 patients underwent distal pancreatectomy. We used the clinical database registry system of the Gangnam Severance Hospital and Severance Hospital, Yonsei University Health System for these analyses. The receiver operating characteristic curve of the drain amylase or lipase concentration on each day was used to predict clinical PF (International Study Group on Pancreatic Fistula [ISGPF] grade B or C) and areas under the curves (AUC) were compared.

Amylase and lipase AUC values poorly predicted clinical PF before POD 3 and, gradually increased until POD 5 and became well correlated with clinical PF (ISGPF grade B or C). In contrast, the prediction of clinical PF using drain lipase did not differ from that using drain amylase. The drain amylase concentration on POD 6 was most precisely correlated with clinical PF.

Clinical PF prediction was validated by using drain amylase and lipase concentrations, in which drain amylase assessment at POD 6 appeared to be an appropriate diagnostic criterion of PF after distal pancreatectomy. We suggest some modification of ISGPF definition, especially for distal pancreatectomy.