Intraductal papillary mucinous neoplasms of the pancreas--predictors of malignancy.

Background/aims Preoperative determination of malignancy in Intraductal Papillary Mucinous Neoplasms (IPMN) remains problematic. The aim of this study was to review our experience with surgical resection for IPMN and to identify the clinicopathological features that predicted malignancy in IPMN. Methodology Forty patients who underwent pancreatic resection for IPMN at a single tertiary center between January 1996 and March 2008 were retrospectively analyzed. Results Thirteen patients (32.5%) had adenomas, 4 (10%) borderline IPMN, 18 (45%) carcinoma in situ, and 5 (12.5%) invasive carcinoma. Patients with benign IPMN had 1-, 3-, and 5-year overall survival rates of 100%, 94.1%, and 88.2%, respectively and 1-, 3-, and 5-year disease-free survival rates of 100%, 94.1%, and 88.2%, respectively. Patients with malignant IPMN had 1-, 3-, and 5-year overall survival rates of 100%, 65.2%, and 56.5%, respectively and 1-, 3-, and 5-year disease-free survival rates of 91.3%, 47.8%, and 43.5% respectively. After a median follow-up of 39 months (range, 9 - 89) months, there were 5 patients with disease recurrences (12.5%) in patients with IPMN with invasive carcinoma after operation. Abdominal pain, jaundice, main-duct or mixed type, tumor size, mural nodule and size of mural nodule, were predictive of malignant IPMN by univariate analysis, and size of mural nodule was identified as the only independent predictive factor for malignancy. Conclusions The optimal management of IPMN remains controversial and should be individualized based on the balance between risk and benefit.