Surgical treatment of intraductal papillary-mucinous tumors of the pancreas

Background/Aims: IPMT (Intraductal papillary-mucinous tumor of the pancreas) is increasingly recognized. The aim of this study was to investigate the appropriate surgical treatment for these tumors. Methodology: Between January 1981 and September 1998, 62 patients with IPMT underwent surgery. We retrospectively examined the clinicopathological features and surgical outcomes of the patients. Results: The types of IPMT were as follows: hyperplasia (20); adenoma (31); and carcinoma, both invasive (5) and noninvasive (6). Lymph node metastasis was found in 36% of the carcinomas. The size of mural nodules was more than 3mm in all adenoma or carcinoma cases, while the percentage of hyperplasia less than 3mm was 75%. Intraoperative pancreatoscopy and annular array ultrasonography were very useful, because they detected 10 lesions that could not be found by preoperative examinations, such as computed tomography, endoscopic retrograde pancreatography, and endoscopic ultrasonography. All patients underwent surgical resection, including 10 pancreaticoduodenectomies (Whipple's procedure), 10 pylorus-preserving pancreaticoduodenectomies, 13 pancreatic head resections with segmental duodenectomies, 17 distal pancreatectomies, 9 segmental resections of the pancreas, 2 duodenum-preserving pancreatic head resections, and 1 total pancreatectomy. No operative or hospital death was observed. The postoperative survival rate at 5 years was 71.6% for carcinoma in IPMT. All of the cases with hyperplasia, adenoma and noninvasive carcinoma survived. Only two of the patients with invasive carcinoma died. Conclusions: IPMT had a favorable prognosis, as compared with pancreatic duct carcinoma. When selecting a surgical procedure for treating these tumors, it is important to confirm the tumor extent, as well as the diagnosis of invasion or noninvasion. In cases with invasion, radical resection is required. On the other hand, organ-function-preserving procedures should be selected for diseases without invasion.