Intraductal papillary mucinous tumor of the pancreas: Usefulness of endoscopic ultrasonography in differentiation of benign and malignant neoplasm

The purpose of this study was to evaluate the usefulness of endoscopic ultrasonography (EUS) in the differential diagnosis of benign and malignant intraductal papillary mucinous tumor of the pancreas. Seven patients with intraductal papillary mucinous tumor of the pancreas confirmed by operation underwent EUS. After evaluation of findings of EUS, these observations were computed with pathologic findings, and then reevaluated them according to the histologic grade of malignancy. According to the pathologic specimens, three cases of them were malignant and the remaining 4 cases were benign. The subtypes of them were as follows: 2 main duct type, 2 branch duct type, and 3 combined type. All malignant tumors showed the main pancreatic duct dilatation (5-15 mm, mean 9.7 mm) , whereas all benign tumors showed no dilatation of the main pancreatic duct on EUS. The mural nodules of the malignant tumors (12-14 mm) were significantly larger than those od benign lesions (3-4 mm), significantly. EUS is useful for diagnosing intradutal papillary mucinous tumor of the pancreas, particularly for predicting malignancy.