Clinical validation of the 2017 international consensus guidelines on intraductal papillary mucinous neoplasm of the pancreas

Purpose: The 2017 international consensus guidelines (ICG) for intraductal papillary mucinous neoplasm (IPMN) of the pancreas were recently released. Important changes included the addition of worrisome features such as elevated serum CA 19-9 and rapid cyst growth (> 5 mm over 2 years). We aimed to clinically validate the 2017 ICG and compare the diagnostic performance between the 2017 and 2012 ICG. Methods: This was a retrospective cohort study. During January 2000-January 2017, patients who underwent complete surgical resection and had pathologic confirmation of branch-duct or mixed-type IPMN were included. To evaluate diagnostic performance, the areas under the receiver operating curves (AUCs) were evaluated. Results: A total of 448 patients were included. The presence of mural nodule (hazard ratio [HR], 9.12; 95% confidence interval [CI], 4.60-18.09; P = 0.001), main pancreatic duct dilatation (> 5 mm) (HR, 5.32; 95% CI, 2.67-10.60; P = 0.001), thickened cystic wall (HR, 3.40; 95% CI, 1.51-7.63; P = 0.003), and elevated CA 19-9 level (> 37 unit/mL) (HR, 5.25; 95% CI, 2.05-13.42; P = 0.001) were significantly associated with malignant IPMN. Malignant lesions showed a cyst growth rate > 5 mm over 2 years more frequently than benign lesions (60.9% vs. 29.7%, P = 0.012). The AUC was higher for the 2017 ICG than the 2012 ICG (0.784 vs. 0.746). Conclusion: The new 2017 ICG for IPMN is clinically valid, with a superior diagnostic performance to the 2012 ICG. The inclusion of elevated serum CA 19-9 level and cyst growth rate to the 2017 ICG is appropriate.