ENDOSCOPIC DIAGNOSIS OF INTRADUCTAL PAPILLARY-MUCINOUS NEOPLASM OF THE PANCREAS BY MEANS OF PERORAL PANCREATOSCOPY USING A SMALL-DIAMETER VIDEOSCOPE AND NARROW-BAND IMAGING

Abstract

Intraductal papillary-mucinous neoplasm (IPMN) is an intraductal tumor in which the mucin-producing epithelium shows proliferated papillary and a wide variety of pathological changes ranging from hyperplasia to adenocarcinoma. Therefore, it is important to determine whether an IPMN is benign or malignant. In the present study of patients with IPMN, the protrusion was observed by a peroral pancreatoscopy (PPS) using a small-diameter videoscope and narrow-band imaging (NBI). We carried out the differential diagnosis of benign lesion to malignant lesion. Between April 2003 and May 2009, PPS using a small-diameter videoscope by means of NBI was carried out on 21 hospitalized patients with IPMN (10 cases of adenocarcinoma, 11 cases of adenoma or hyperplasia; 14 males and seven females, with a mean age of 69.4 years). Fifteen focal lesions of the 16 cases in the head of the pancreas (93.7%) and four focal lesions of the five cases in the pancreatic body (80%) were observable, whereas two lesions (adenocarcinoma in the pancreatic body, and adenoma in the uncus of pancreas) were not observable. Endoscopically, seven cases were classified as villous type and two cases as vegetative type, and nine cases were diagnosed as adenocarcinoma. Ten cases with sessile type or semipedunculated type were diagnosed as adenoma or hyperplasia. Vascular patterns and protrusions were detected more clearly in the NBI images than under white light observation. When combined with a videoscope and NBI, pancreatoscopy provided a clear image and was useful for evaluating whether the IPMN was benign or malignant.