Predictors of malignancy in pure branch duct type intraductal papillary mucinous neoplasm of the pancreas: A nationwide multicenter study

Abstract

Background/Objectives: Prediction of malignancy in patients with BD-IPMNs is critical for the management. The aim of this study was to elucidate predictors of malignancy in patients with ‘pure’ BD-IPMNs who had a main pancreatic duct (MPD) diameter of 5 mm according to the most recent international consensus criteria and in whom MPD involvement was excluded on postoperative histology. Methods: We identified 177 patients with ‘pure’ BD-IPMNs based on preoperative imaging and postoperative histology from 15 tertiary referral centers in Korea. BD-IPMNs with low-grade (n ¼ 72) and moderate-grade (n ¼ 66) dysplasia were grouped as benign and BD-IPMNs with high-grade dysplasia (n ¼ 10) and invasive carcinoma (n ¼ 29) were grouped as malignancy. Results: On univariate analysis, particular symptoms (jaundice and clinical pancreatitis), CT findings (cyst size > 3 cm, the presence of enhancing mural nodules) and EUS features (the presence of mural nodules, the mural nodule size > 5 mm) were significant risk factors predicting malignant BD-IPMNs. Multivariate analysis revealed that the cyst size > 3 cm (odds ratio ¼ 9.9), the presence of enhancing mural nodules on CT (odds ratio ¼ 19.3) and the mural nodule size > 5 mm on EUS (odds ratio ¼ 14.9) were the independent risk factors for the presence of malignancy in BD-IPMNs (p < 0.001).