Intraductal papillary mucinous neoplasm of the pancreas: clinical characteristics and treatment outcomes of 118 consecutive patients from a single center

Abstract
Appropriate surgical treatment strategies based on clinicopathological findings are unavailable for intraductal papillary mucinous neoplasm (IPMN) of the pancreas. We investigated the clinical features of pancreatic IPMN in a single-center database in order to design an optimal surgical strategy. The medical records of 118 consecutive patients who had undergone surgical resection between August 1994 and December 2004, in whom IPMN was histologically confirmed, were reviewed retrospectively for radiological and pathological findings. Most of the invasive carcinomas in these patients were detected as the main-duct type (88.5%). The type of tumor (main-duct type vs branched-duct type), the tumor size, and the dilated duct size were significant predictive factors associated with malignancy. The relative risk of malignancy was greatest at 13-mm or more ductal dilation in the main-duct type (Odds ratio, 4.1), at 35-mm or more tumor size (Odds ratio, 7.6), and for main-duct type (Odds ratio, 3.9). Major pancreatic resections such as total pancreatectomy and pancreatoduodenectomy were performed in 14.5% and 69% of the patients, respectively. There was a 19.5% rate of incomplete resection, with these patients having a positive resection margin. However, significant recurrence did not occur in patients with a benign IPMN lesion which remained at the resection margin. The overall postoperative survival rate at 5 years was 98.2% for benign IPMN and 65.3% for malignant IPMN. Function-preserving strategies, based on the clinical status of the patient, are necessary in order to avoid possible severe metabolic complications following extended pancreatectomy in patients with benign IPMN because of the low recurrence rate and good prognosis of this entity, irrespective of margin status.