Predictive factors associated with malignancy of intraductal papillary mucinous pancreatic neoplasms

AIM: To identify preoperative predictive factors associated with malignancy of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.METHODS: Between April 1995 and April 2010, 129 patients underwent surgical resection for IPMNs at our institute and had confirmed pathologic diagnoses. The medical records were retrospectively reviewed and immunohistochemical staining for mucin (MUC) in pancreatic tissues was performed.RESULTS: Univariate analysis showed that the following five variables were closely associated with malignant IPMNs preoperatively: absence of extrapancreatic malignancy; symptoms; tumor size > 4 cm; main pancreatic duct (MPD) size > 7 mm; and lymph node enlargement on preoperative computed tomography (CT). Multivariate analysis revealed that the following two factors were significantly associated with malignant IPMNs preoperatively: MPD size > 7 mm [odds ratio (OR) = 2.50]; and lymph node enlargement on preoperative CT (OR = 3.57). No significant differences in the expression of MUC1, MUC2 and MUC5AC were observed between benign and malignant IPMNs.CONCLUSION: MPD size > 7 mm and preoperative lymph node enlargement on CT are useful predictive factors associated with malignancy of IPMNs.