How many millimeters do atypical epithelia of the pancreas spread intraductally before beginning to infiltrate?

BACKGROUND/AIMS: The pathogenesis of ordinary duct cell carcinoma of the pancreas is still unclear. The aim of this study was to identify which epithelial lesion was a precursor of duct cell carcinoma and to determine how many millimeters atypical epithelia spread intraductally before beginning to infiltrate. METHODOLOGY: Small cystic dilated lesions were studied, using 1374 autopsied pancreata which were mainly taken from aged patients. Serial sections were taken at about 5-mm intervals. Small cystic dilated lesions were defined as restricted dilatations of the pancreatic branch duct, which were grossly recognizable and therefore larger than about 1-2 mm in diameter. The degree of epithelial atypia of the cystic dilated lesions was histologically divided into five groups (Group I to V). RESULTS: Comparing PanIN to our classification, normal and squamous metaplasias were almost the same as Group 1. PanIN 1A and 1B almost the same as Group 2 (benign hyperplasia). PanIN-2 is almost the same as Group 3, and PanIN-3 is almost the same as Group 4, which is characterized by true cribriforming, and a loss of nuclear polarity. Of 1374 autopsy cases, small cystic dilated lesions were found in 378 pancreata (27.5%). Histological examination revealed that the incidence of each group was 47%, 33%, 18%, 2.4% and 0.6% of 507 cystic dilated lesions, respectively. Dilatation of the cystic lesion and surrounding dilated duct resembled a precursor of IPMT in four cases, but not in another five cases. Group IV epithelia just infiltrated in some of the latter cases. Invasion was found when Group IV epithelia spread about 5-8 mm, while it rarely infiltrated when it spread less than 4 mm. CONCLUSIONS: The pathogenesis of ordinary duct cell carcinoma of the pancreas was speculated to begin with papillary growth of duct epithelia. Papillary atypical epithelia then begins to infiltrate when they spread intraductally about 5-8 mm.     

Operative indications for cystic lesions of the pancreas with malignant potential--our experience

BACKGROUND/AIMS: There are still many important but unclear points regarding the differential diagnosis and operative indications of cystic lesions of the pancreas with malignant potential. Studies of the clinicopathological and molecular biological characteristics of such diseases are necessary. In this paper, we discuss operative indications for this condition based on a review of the literature and our own experience. METHODOLOGY: Seven cases of serous cystadenoma and 9 cases of mucinous cystadenoma or cystadenocarcinoma of the pancreas that were operated on or autopsied in our department from 1980 to 1996 were analyzed clinicopathologically. Small cystic lesions incidentally found in 300 autopsied cases were also studied. Finally, mucin-producing tumors described in several reports were reviewed, and the branch type of this tumor was especially investigated. RESULTS: A marked disappearance of pancreatic acini in the upstream pancreas was found when serous cystadenoma became large. Papillary projection was histologically found in all of the cases. Tumorous invasion to the interstitium was suspected in tumors more than 5 cm in diameter, and malignancy was reported when tumors were larger than 6 cm. As for mucinous cystadenocarcinoma, the patients had a poor prognosis. In 2 of 42 cases with a pseudocyst, small duct cell carcinoma was incidentally found adjacent to the pseudocyst on the duodenal side. With regard to branch-type intraductal papillary neoplasm, 80% of the tumors larger than 4 cm were malignant. Most of the small cystic lesions found in elderly autopsy cases were accompanied by hyperplastic epithelia without evidence of malignancy. CONCLUSIONS: Based on our experience, an operation should be considered and resection is recommended under the following circumstances: 1) cystic lesions in the body and tail of the pancreas in middle-aged women; 2) typical serous cystadenoma larger than 4 cm; 3) mucinous cystadenoma of any size; 4) branch-type intraductal papillary neoplasm larger than about 3 cm; and, 5) pseudocysts of unknown cause. Small cystic lesions in elderly patients should not necessarily be operated on, but should be followed-up carefully.     

Intraductal mucinous tumors occurring simultaneously in the liver and pancreas

A case of simultaneous intraductal mucinous tumors of the liver and pancreas in a 67-year-old man is described. Abdominal ultrasonography and computed tomography (CT) revealed the presence of cystic lesions with intraluminal septae both in the caudate lobe of the liver and in the uncinate process of the pancreas; these cystic lesions communicated with the hepatic duct and pancreatic duct, respectively. Mucin retention was observed in the cysts, and cholestasis was induced by mucin secretion into the common bile duct. The lesions were resected by left hepatic lobectomy with caudate lobectomy, and segmental pancreatectomy. Both lesions were multilocular cystic tumors with no papillary projections or focal mass effect in their walls. Histologically, both cystic lesions were a mixture of hyperplasia and adenoma lined by low papillary columnar epithelium. There were no cellular or histological features to suggest malignant change. The fibrous intratumor interstitium lacked any mesenchymal or ovarian-like stroma. The hepatic lesion was considered to be of a similar nature to intraductal papillary mucinous tumor (IPMT) of the pancreas. However, the two lesions occurred simultaneously in the liver and pancreas. This case is of interest in regard to the diagnosis and management of mucinous hepatopancreatobiliary lesions. Received: March 16, 2001 / Accepted: September 14, 2001     

Endoscopic ultrasound characteristics of mucinous cystic neoplasms of the pancreas

OBJECTIVE: Mucinous cystic neoplasms of the pancreas have a more favorable prognosis than ductal adenocarcinoma. Management of a subgroup, intraductal papillary-mucinous neoplasms, is controversial. Endoscopic ultrasound (EUS) with fine-needle aspiration biopsy may emerge as the imaging modality of choice. There are few studies describing the EUS features of these tumors. METHODS: A total of 35 consecutive cases of cystic tumors of the pancreas with an established pathological diagnosis were analyzed for characteristic EUS features. RESULTS: Mucinous cystadenocarcinomas (n = 14) were more likely to be characterized by hypoechoic cystic/solid mass or complex cyst and were frequently associated with a dilated main pancreatic duct. Benign mucinous duct ectasia (n = 6) were characterized by a dilated main pancreatic duct in conjunction with hyperechoic thickening of the duct wall. The two cases of intraductal mucinous hyperplasia additionally showed a hypoechoic mass. Intraductal papillary carcinoma (n = 11) had features in common with mucinous cystadenocarcinoma but also had echogenic foci in the mass and intraductal hyperechoic lesions. The two cases of microcystic cystadenoma showed either a mixed hypoechoic solid/cystic mass or a complex cyst without the additional features seen in mucinous cystadenocarcinoma. CONCLUSIONS: EUS features seem to exist that may help to differentiate cystic neoplasms from adenocarcinoma of the pancreas and, thus, to establish the preoperative diagnosis of cystic tumors of the pancreas.     

Mirizzi syndrome secondary to an adenoma of the cystic duct

Bile duct adenomas are uncommon lesions that can cause obstructive jaundice. We report the unusual case of a 54-year-old man who developed Mirizzi syndrome secondary to a bile duct papillary adenoma located in the cystic duct remnant. A case report is presented, together with a review of extrahepatic bile duct adenomas published in the English-language literature, with special attention directed toward the clinical manifestations, locations, and prognosis of these tumors. Bile duct adenomas are very rare tumors. Although cholangiography can detect many of these lesions, few cases were correctly diagnosed preoperatively. Most lesions were located in the distal common bile duct or at the ampulla of Vater. Pathologic examination often revealed foci of carcinoma in situ, dysplasia, or atypia. Local resection was performed in most cases. There were no previous case reports of extrinsic common bile duct obstruction caused by tumors within the cystic duct. We describe here a very rare, acalculous variant of Mirizzi syndrome secondary to a solitary papillary adenoma of the cystic duct. In general, bile duct adenomas are uncommon lesions that are difficult to diagnoses preoperatively. These tumors usually present with jaundice secondary to intraluminal biliary obstruction. These lesions are premalignant and should be managed by complete surgical resection.     

Correlation between ultrasonographic findings and pathological diagnosis of mucin producing tumor of the pancreas

We reviewed 19 cases of so-called mucin producing tumor of the pancreas ultrasonographically and histopathologically. Conventional ultrasonography could detect 16 cases out of 19 (84%). But its detectability of localized cystic lesion or papillary projection in the cystic lesion was 68%. On the contrary, endoscopic ultrasonography could visualize such changes in 93% of the cases. In the case which have neoplastic change, it is considered that the portion showing papillary proliferation is correspondent to the ultrasonographic findings of irregularity of the wall of the pancreatic duct or thickened septum-like structure. In the cases which are diagnosed as hyperplasia, the cystic lesions are delineated as having smooth and thin septum-like structure.     

Multifocal intraductal papillary mucinous neoplasm of the pancreas-A case report

Cystic neoplasms of the pancreas are relatively rare, comprising 10 percent of pancreatic cysts and only 1 percent of pancreatic cancers. Cystic neoplasms include mucinous cystic neoplasms, serous cystadenomas, papillary cystic tumors, cystic islet cell tumors and intraductal papillary mucinous neoplasms of the pancreas （IPMNs）. IPMN was first described in 1982. It has been most commonly described in 60 to 70 years old males, and represents a relatively ＂new＂ but increasingly recognized disease. The improvement and widespread use of modern imaging equipments and heightened awareness of physicians contribute to the increasing incidence of IPMN. The majority of IPMNs are located in the pancreatic head （75%） while the rest involves the body/tail regions. Multifocal IPMNs have been hypothesized, but the true presence of multifocality is unknown. Here we present a 72-year- old male diagnosed with IPMN （carcinoma in situ） in the pancreatic head and a branch duct type IPMN （duct atypia） in the pancreatic body and tail. The patient underwent a Whipple intervention and a distal pancreatectomy. A three-year disease-free survival has been observed so far.     

Immunohistochemical analysis of expression of molecular biologic factors in intraductal papillary-mucinous tumors of pancreas--diagnostic and biologic significance.

BACKGROUND/AIMS: In this study we investigated the expressions of molecular biologic factors, p53, rasp21, bcl-2, c-erbB-2, and Ki-67 by immunohistochemical method in intraductal papillary-mucinous tumor of the pancreas to identify their diagnostic values and to determine their relations to the degree of histopathologic abnormalities. METHODOLOGY: Thirty-eight different histologic lesions from 28 patients of intraductal papillary-mucinous tumor of the pancreas, comprising normal pancreatic duct (n = 6), intraductal papillary hyperplasia (n = 6), intraductal adenoma (n = 15), and intraductal carcinoma (n = 11) were immunostained by the avidin-biotin peroxidase conjugate method. RESULTS: p53 and Ki-67 expressions were significantly greater in malignant intraductal papillary-mucinous tumor than in their benign counterpart (p = < 0.0001), while rasp21 showed gradual increase in the frequency of expression from normal pancreatic duct (0%), to intraductal hyperplasia (16.7%), to intraductal adenoma (26.7%), and ultimately to intraductal carcinoma (63.6%). bcl-2 and c-erbB-2 were not expressed in any lesions. CONCLUSIONS: These results suggest that p53 and Ki-67 expressions have significant diagnostic values in differentiating benign intraductal papillary-mucinous tumors from malignant ones and thus can facilitate in the pre-operative planning of treatment in individual cases. Secondly, gradual stepwise increase in the frequency of rasp21 expression with increasing degree of cellular atypia supports the presence of adenoma-carcinoma sequence in the carcinogenesis of this tumor.     

Endoluminal ultrasonography for pancreatic diseases.

Endoluminal ultrasonography was performed on 146 patients with pancreatobiliary diseases by using high-frequency, thin ultrasonic probes, and the usefulness of the new technique in diagnosis of pancreatic diseases was reported. The ultrasound probe could be inserted into the main pancreatic duct in 43 of 46 patients (93.5%), and images of the lesions could be obtained in 42 patients (91.3%). Endoluminal ultrasonography revealed a hypoechoic mass with clear margins and central echogenicity in patients with pancreatic carcinoma. Endoluminal ultrasonography showed normal pancreatic parenchyma as a fine reticular pattern and did not reveal the tumors surrounding the stenosis in patients with focal pancreatitis. Endoluminal ultrasonography in patients with intraductal papillary adenocarcinoma of the pancreas revealed cystic lesions with mural nodules more than 4 mm, mucus echoes, and solid tumors with mixed echo patterns. There were no severe complications, and acute pancreatitis occurred in none of 46 patients, but high-level serum amylase after examination occurred in 5 patients (10.9%). Endoluminal ultrasonography is useful for differential diagnosis in patients with small pancreatic tumors or cystic lesions, especially intraductal papillary tumors of the pancreas. Endoluminal ultrasonography is recommended as a precise examination for the diagnosis of cystic lesions of the pancreas or stenosis of the main pancreatic duct after ERCP and EUS.     

Intraductal carcinoma in a surgically resected pancreas with chronic pancreatitis

A 59-yr-old Japanese male presented with epigastralgia. Endoscopic retrograde cholangiopancreatography (ERCP) revealed narrowing of the inferior common bile duct and protein plugs in the main pancreatic duct. He was diagnosed as suffering from chronic pancreatitis with suspicion of a pancreatic head tumor, and a pancreatoduodenectomy was performed. Histologically, a diffuse chronic pancreatitis was evident in the resected pancreas. Although no tumors were seen in the head portion of the pancreas around the inferior common bile duct, an intraductal carcinoma was found in the second branch of Santorini’s duct. Precancerous alteration of the duct epithelium, presenting papillary hyperplasia, and atypical hyperplasia were observed in areas continuous with the intraductal carcinoma. Immunohistochemically, carcinoembronic antigen (CEA) was specifically expressed in atypical hyperplasia and intraductal carcinoma, but not in papillary hyperplasia.     

Ductal adenocarcinoma of the head of the pancreas: incidence of tumor involvement beyond the Whipple resection line. Histological and immunocytochemical analysis of 37 total pancreatectomy specimens

Intrapancreatic tumor spread of ductal adenocarcinoma of head of pancreas was examined histologically in 37 total pancreatectomy specimens. Five to 10 tissue blocks were prepared from grossly tumor-free tissue of each pancreas and coded by anatomic location. Step sections from each block were analyzed for carcinoma in situ lesions, invasive carcinoma, and benign ductal lesions. Immunocytochemical staining with monoclonal antibodies (MAb) against carcinoembryonic antigen (CEA) and nonspecific cross-reacting antigen 95 (NCA 95) were used to help in discriminating carcinoma in situ from papillary duct hyperplasia. In 3 of 37 pancreatectomy specimens (8%) tumor was found to spread in continuity from the primary carcinoma into the body and tail. In two of these three cases with tumor beyond the usual Whipple resection line, the tumor was present as a "carcinoma in situ" lesion along the main pancreatic duct. Since discontinuous tumor growth was not observed, multicentricity of duct type adenocarcinoma seems to occur less frequently than was previously reported.     

European experts consensus statement on cystic tumours of the pancreas

Cystic lesions of the pancreas are increasingly recognized. While some lesions show benign behaviour (serous cystic neoplasm), others have an unequivocal malignant potential (mucinous cystic neoplasm, branch- and main duct intraductal papillary mucinous neoplasm and solid pseudo-papillary neoplasm). European expert pancreatologists provide updated recommendations: diagnostic computerized tomography and/or magnetic resonance imaging are indicated in all patients with cystic lesion of the pancreas. Endoscopic ultrasound with cyst fluid analysis may be used but there is no evidence to suggest this as a routine diagnostic method. The role of pancreatoscopy remains to be established. Resection should be considered in all symptomatic lesions, in mucinous cystic neoplasm, main duct intraductal papillary mucinous neoplasm and solid pseudo-papillary neoplasm as well as in branch duct intraductal papillary mucinous neoplasm with mural nodules, dilated main pancreatic duct >6 mm and possibly if rapidly increasing in size. An oncological partial resection should be performed in main duct intraductal papillary mucinous neoplasm and in lesions with a suspicion of malignancy, otherwise organ preserving procedures may be considered. Frozen section of the transection margin in intraductal papillary mucinous neoplasm is suggested. Follow up after resection is recommended for intraductal papillary mucinous neoplasm, solid pseudo-papillary neoplasm and invasive cancer.     

Pancreatic cancer in patients with pancreatic cystic lesions: a prospective study in 197 patients.

BACKGROUND & AIMS: K-ras mutation is frequently detected in pancreatic juice of patients with pancreatic small cystic lesions, as well as those with pancreatic cancer. Those cystic lesions are often found by chance with modern radiologic imaging modalities. In this study, we prospectively examined the prognosis of patients with pancreatic cystic lesions, focusing on pancreatic cancer development. METHODS: A total of 197 patients with pancreatic cystic lesions, 80 with intraductal papillary mucinous neoplasm (IPMN) and 117 with non-IPMN cysts, were followed up for 3.8 years on average. Blood tests and imaging diagnosis were performed twice a year. The observed incidence of pancreatic cancer was compared with the expected incidence calculated on the basis of age- and gender-matched mortality of pancreatic cancer in the general Japanese population. RESULTS: Pancreatic cancer developed in 7 patients during the observation period (0.95% per year), infiltrating ductal carcinoma in 5 and intraductal papillary mucinous carcinoma in 2. Three of the ductal cancer cases had pancreatic non-IPMN cyst as preexisting lesion. At least 2 of the carcinomas arose in regions remote from preexisting lesions. The observed incidence of pancreatic cancer was 22.5 times higher (95% confidence interval, 11.0-45.3) than expected mortality from this cancer among general population. CONCLUSIONS: Patients with pancreatic cystic lesions are at a considerably high risk for pancreatic cancer, with a standardized incidence rate of 22.5. Cancer might develop in regions remote from the preexisting cystic lesion, suggesting diffuse pathologic changes predisposing to malignant transformation in the entire pancreas harboring cystic lesions.     

Simultaneous transition of multiple polyps into carcinoma in the large intestine

Conclusion The histologic grades of multiple neoplastic lesions in the large intestines of 41 patients were studied. Of the 41 patients, 16 had multiple polyps, 12 each had a carcinoma as well as one or more polyps, and the remaining 13 each had two or more carcinomas. Differences in the grades of histologic atypia among multiple neoplastic lesions were minimal. Therefore, the multiple neoplastic lesions present were considered to have airsen simultaneously or successively within a relatively short period of a given patient's life, rather than randomly in different periods. Of 25 patients who had carcinomain situ or infiltrating carcinoma, 17 had accompanying precancerous conditions or carcinoma elsewhere in the large intestine, and the remaining eight had accompanying nonmalignant polyps.     

Mucin-producing adenoma associated with pancreas divisum and hepatic hilar carcinoma: An autopsy case

We present the autopsy case of an 82-year-old Japanese woman with a mucin-producing adenoma accompanied by pancreas divisum and a hepatic hilar carcinoma. She had suffered from a cholangiocellular carcinoma at the hepatic hilus for 2 months, which was treated with radiation and chemotherapy. She did not complain of any abdominal pain. Obstructive jaundice deteriorated despite percutaneous transhepatic bile duct drainage, and she died of hepatic insufficiency. At autopsy, a hepatic tumor was confirmed to have caused severe obstructive jaundice. Histological examinations showed moderately to poorly differentiated cholangiocellular adenocarcinoma with squamous metaplasia, probably due to radiation. A yellowish mucinous tumor was found in the head of the pancreas near the minor papilla. It consisted of multiple rice-sized cystic lesions with thin septa. Although it had no capsule, its margin was clear. Neither a wide opening of the major or minor papilla nor mucous drainage was observed. Gross examinations revealed unfused pancreatic ducts. The slightly dilated dorsal duct and a branch of the mildly dilatated ventral duct showed tumor involvement. Histological examinations showed mild atypia of the epithelia, and this pancreatic tumor was diagnosed as branch duct-type mucin-producing adenoma with postradiation dysplasia. The combination of a mucin-producing tumor and pancreas divisum is rare, and this is only the third reported case.     

Differential diagnosis of intraductal papillary‐mucinous tumor of the pancreas by endoscopic ultrasonography and intraductal ultrasonography

Background: Intraductal papillary‐mucinous tumor (IPMT) of the pancreas has a broad spectrum of histology ranging from hyperplasia to adenocarcinoma. Therefore, it is important to differentiate between the malignant and benign lesions to determine the therapeutic strategy for IPMT. Patients and Methods: Thirty‐nine patients with IPMT (27 men and 12 women, mean age: 63.3 years) underwent surgery between January 1985 and March 2002. The size of the cystic lesion, the maximum diameter of the main pancreatic duct (MPD), and the height of the papillary tumor inside the cyst were investigated by endoscopic ultrasonography (EUS) and/or intraductal ultrasonography (IDUS) before operation. These preoperative clinical findings were compared with the pathological findings of the resected specimen. Results: The size of the cystic lesion, the diameter of MPD, and the height of the papillary tumor in cases with malignant IPMT (invasive and non‐invasive carcinoma) were larger than those in cases with benign IPMT (adenoma and hyperplasia). Analysis of the images of the lesions revealed that the following three factors are important for diagnosing IPMT: (i) the size of the cystic lesion is ≥ 30 mm; (ii) the diameter of MPD is ≥ 8 mm; (iii) the height of the papillary tumor inside the cyst is ≥ 3 mm. It was not significant to differentiate between benign and malignant IPMT based on factor (i), but statistically significant (P < 0.001) based on factors (ii) and (iii). Conclusions: EUS and IDUS are useful in the differential diagnosis of IPMT, especially in the differentiation between malignant and benign IPMT.     

Multicentric pancreatic intraepithelial neoplasias (PanINs) presenting with the clinical features of chronic pancreatitis

A 46-year-old woman was readmitted to our hospital in August 2005 because of severe abdominal pain and nausea. Computed tomography demonstrated a huge cystic lesion in the retroperitoneal space behind the hepatoduodenal ligament and lesser peritoneal cavity. Endoscopic retrograde pancreatography revealed communication between the dilated main pancreatic duct and a pseudocyst. The condition was preoperatively diagnosed as chronic pancreatitis associated with a pseudocyst or an intraductal papillary mucinous neoplasm without mucin hypersecretion. The patient underwent a distal pancreatectomy with splenectomy. The pathologic diagnosis was multicentric pancreatic intraepithelial neoplasia (PanIN), and histological examination revealed a positive surgical margin around the remnant pancreas. Four months after the surgery, the patient underwent a total pancreatectomy. Macroscopic observation revealed diffuse fibrosis of the pancreatic parenchyma compatible with chronic pancreatitis. Histological examination revealed a constellation of noninvasive intraductal neoplasias with high-grade atypia, diffusely distributed in the small pancreatic ducts of the resected pancreas. Localized fibrosis and cystic dilation of the small ducts were detected in a lobule of exocrine glands draining into a ductule involved by PanIN lesions in the head of the pancreas. In summary, multicentric PanIN lesions are associated with lobular atrophy of the pancreatic parenchyma and chronic pancreatitis-like changes that follow. Total pancreatectomy may be recommended for patients with multicentric precursor lesions throughout the entire pancreas.     

A series of 64 cases of pancreatic cystic neoplasia from an institutional study of China

INTRODUCTION Cystic neoplasia of the pancreas accounts for about 10%-15% of all cystic pancreatic lesions[1]. The majority of cystic lesions of the pancreas are pseudocysts. Although cystic neoplasia of the pancreas is rare, it encompasses a spectrum of b…     

Peroral cholangioscopy for non-invasive papillary cholangiocarcinoma with extensive superficial ductal spread

Papillary carcinoma arising from the extrahepatic bile duct often shows superficial ductal spread. We report herein the case of a patient with extensive superficial spread of non-invasive papillary cholangiocarcinoma, which was depicted with peroral cholangioscopy. A 65-year-old woman presented with the sudden-onset of severe epigastric pain. Ultrasonography revealed acute acalculous cholecystitis. Endoscopic retrograde cholangiography found small protruding lesions around the confluence of the cystic duct, suggestive of a cholangiocarcinoma. As the contour of the middle and upper bile ducts it was slightly irregular on the cholangiogram, the presence of superficial ductal spread was suspected. Peroral cholangioscopy revealed small papillary lesions around the confluence of the cystic duct and fine granular mucosal lesions in the middle and upper bile ducts and the right hepatic duct, suggesting a superficially spreading tumor. A right hepatectomy with bile duct resection was performed and no residual tumor was found. Histological examination revealed a non-invasive papillary carcinoma arising from the cystic duct with extensive superficial spread. Our experience of this case and a review of the literature suggest that a fine granular or fine papillary appearance of the ductal mucosae on cholangioscopy indicates superficial spread of papillary cholangiocarcinoma, for which peroral cholangioscopy is an efficient diagnostic option.     

Management of intraductal papillary mucinous neoplasm of the pancreas

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a distinct entity characterized by papillary proliferations of mucin-producing epithelial cells with excessive mucus production and cystic dilatation of the pancreatic ducts. IPMNs have malignant potential and exhibit a broad histologic spectrum, ranging from adenoma to invasive carcinoma. IPMNs are classified into main duct and branch duct types, based on the site of tumor involvement. IPMN patients have a favorable prognosis if appropriately treated. The postoperative 5-year survival rate is nearly 100% for benign tumors and noninvasive carcinoma, and approximately 60% for invasive carcinoma. A main duct type IPMN should be resected. Surgical treatment is indicated for a branch duct IPMN with suspected malignancy (tumor diameter ≥ 30 mm, mural nodules, dilated main pancreatic duct, or positive cytology) or positive symptoms. Malignant IPMNs necessitate lymph node dissection (D1). IPMNs are associated with a high incidence of extrapancreatic malignancies and pancreatic ductal carcinoma.