LAUSR

OBJECTIVE The aim of this study was to develop a classification system for pancreas-associated risk factors in pancreatoduodenectomy (PD). SUMMARY BACKGROUND DATA Postoperative pancreatic fistula (POPF) is the most relevant PD-associated complication. A simple standardized surgical reporting system based on pancreas- associated risk factors is lacking. METHODS A systematic literature search was conducted to identify studies investigating clinically relevant POPF (CR-POPF) and pancreas-associated risk factors after PD. A meta-analysis of CR-POPF rate for texture of the pancreas (soft vs. not-soft) and main pancreatic duct (MPD) diameter was performed using the Mantel-Haenszel method. Based on the results, the ISGPS proposes the following classification: A, not-soft (hard) texture and MPD >3 mm; B, not-soft (hard) texture and MPD ≤3 mm; C, soft texture and MPD >3 mm; D, soft texture and MPD ≤3 mm. The classification was evaluated in a multi-institutional, international cohort. RESULTS Of the 2,917 articles identified, 108 studies were included in the analyses. Soft pancreatic texture was significantly associated with the development of CR-POPF (odds ratio 4.24, 95%CI 3.67 to 4.89, p < 0.01) following PD. Similarly, MPD diameter ≤3 mm significantly increased CR-POPF risk compared with >3 mm diameter MPDs (odds ratio 3.66, 95%CI 2.62 to 5.12, p < 0.01). The proposed four-stage system was confirmed in an independent cohort of 5,533 patients with CR-POPF rates of 3.5%, 6.2%, 16.6%, and 23.2% for type A-D, respectively (p < 0.001). CONCLUSION For future pancreatic surgical outcomes studies the ISGPS recommends reporting these risk factors according to the proposed classification system for better comparability of results.