Intraductal papillary or mucinous tumors (IPMT) of the pancreas: report of a case series and review of the literature

OBJECTIVE: Despite a better understanding of these conditions, intraductal papillary or mucinous tumors (IPMT) of the pancreas still present difficulty relating to the predictive factors of malignancy and the risk of relapse after surgical resection. The aim of this study was to report on our experience and to compare it to previously published cases. METHODS: We studied retrospectively 26 patients (mean age 60.3 yr) presenting with IPMT. Of the 26 patients, 19 had surgical resection and seven did not. The main clinical feature was acute pancreatitis occurring in 38% of the patients. Segmental pancreatectomy was performed in all the cases. At pathological assessment of resection margins, tumor resection was considered as complete in 17 cases. Margins exhibited benign mucinous involvement, and resection was considered to be incomplete in one multifocal case and in one case with diffuse spread of the tumor. RESULTS: A total of 11 tumors were benign and five were malignant. Carcinomas were invasive in four cases (two invading the pancreatic parenchyma, one the duodenum, and one the peripancreatic nodes) and in situ in one case. Malignancy was not diagnosed preoperatively except when invasion was evident (duodenal spread). Although main pancreatic duct type and obstructive jaundice appeared as suggestive features for the risk of malignancy, no reliable preoperative predictive factors for malignancy could be identified as regarding to clinical parameters, biological examinations, carcinoembryonic antigen or CA19-9 levels in serum or in pure pancreatic juice, imaging, and cytological methods. Within 40.8 months mean follow-up after surgery (range 2-96 months), three patients (16%), two with malignant and one with benign tumor, had tumor relapse after respectively 7, 27, and 14 months. Margins were positive without malignant features in the two malignant cases and negative in the other case. Tumor relapse was malignant with diffuse spreading in the three cases, and the patients died within 34 months after surgical resection. CONCLUSIONS: Our series and the review of the literature indicate that preoperative indicators of malignancy in IPMT are still lacking. Concerning resection margins, complete tumor resection is usually possible by segmental pancreatectomy. Malignant relapses are not exceptional. Incomplete resection and diffuse or multifocal tumor represent poor prognostic factors. Total pancreatectomy should be considered in such cases.     

Intraductal papillary-mucinous tumor of the pancreas head with complete absence of the ventral pancreatic duct of Wirsung

A case of intraductal papillary mucinous tumor of the pancreas with complete absence of the ventral pancreatic duct of Wirsung is presented. A 74-year-old Japanese man was admitted to our hospital because of elevated serum amylase concentration. Abdominal computed tomography (CT) scanning revealed diffuse dilatation of the main pancreatic duct and a diffuse and uncircumscribed area with heterogeneous density in the pancreas head. Endoscopic retrograde cholangiopancreatography revealed that the main pancreatic duct was connected with an accessory papilla and was diffusely dilated, without any irregularity of the duct wall being observed in the entire length of the duct. The common bile duct was detected only by cannulation through Vater’s papilla, and no pancreatic duct or its communicating branch was found. Some branches, directed to the dorsal portion of the pancreas head, were found arising from the accessory pancreatic duct. Intraductal ultrasound examination performed through the accessory papilla and the common bile duct revealed a small tumor with a heterogeneous echo level in the pancreas head. From these findings, intraductal papillary-mucinous tumor (IPMT) occurring in the pancreas head was diagnosed, and pylorus-preserving pancreaticoduodenectomy was performed. The resected specimen revealed IPMT in the pancreas head. A roentgenographic study of the resected specimen revealed a defect caused by the tumor located in the pancreatic duct connected with the accessory papilla and showed that there was complete absence of the pancreatic duct connected with Vater’s papilla. Surgical resection enabled us to completely analyze the duct system of pancreas divisum. Although it is not known whether there is a relationship between the pathogenesis of IPMT and embryological anomaly of the pancreatic duct system, this case may provide an insight into the pathogenesis of IPMT.     

Intraductal papillary-mucinous tumor of the pancreas: presentation in a young adult

Intraductal papillary-mucinous tumor (IPMT) of the pancreas is a premalignant lesion that can result in the hypersecretion of mucous and subsequent pancreatitis. In this report, one of the youngest cases of IPMT is described. Initial pancreaticogram was normal. Pathognomonic changes of the pancreatic duct were found only years later; otherwise, the recurrent pancreatitis seen in this patient might have been repeatedly misdiagnosed as idiopathic. Pre- and perioperative evaluation resulted in pancreaticoduodenectomy for what was felt to be a curative resection. However, the patient suffered an aggressive metastatic course. More extensive surgery may be needed in IPMT, such as total pancreatectomy, especially in cases of diffuse ductal dilation of the pancreas.     

PERORAL PANCREATOSCOPY AND INTRADUCTAL ULTRASONOGRAPHY IN DETERMINING THE RESECTION LINES OF INTRADUCTAL PAPILLARY MUCINOUS TUMORS OF THE PANCREAS

In patients with malignant intraductal papillary–mucinous tumors (IPMT), the tumor spread along the main pancreatic duct is generally inspected as mural nodules within the ducts by peroral pancreatoscopy (POPS). Even the lower mural nodules including fish‐eggs‐like lesions and granular mucosa continued to the main taller mural nodules should be resected. Mural nodules along the main duct and cystic dilation of the branch ducts observed by intraductal ultrasonography (IDUS) are regarded as the tumor spread. Although POPS is superior to IDUS in identifying mural nodules along the main duct, POPS has limitations to detect mural nodules within the branch ducts. Therefore, the accuracy of the diagnosis by POPS is higher in main duct IPMT, whereas that by IDUS is higher in branch duct IPMT. These modalities should be performed as complementary tests in determining the resection lines preoperatively.     

Clinicopathologic features and outcomes of intraductal papillary-mucinous tumors of the pancreas

BACKGROUND/AIMS: The authors reviewed their experience with resected IPMT (intraductal papillary-mucinous tumor) of the pancreas to clarify the characteristics and prognosis of this neoplasm. METHODOLOGY: Between 1983 and 1998, 30 consecutive patients with IPMT underwent operations at our institution. Their clinicopathological features and postoperative long-term outcomes were analyzed retrospectively. RESULTS: There were 22 males and 8 females, with a mean age of 64 years. Operations performed were duodenum-preserving pancreatic head resection in 12 patients, distal pancreatectomy in 8, segmental pancreatectomy in 6, conventional pancreaticoduodenectomy in 4. Malignancy was found in 10 of 30 (33%). Factors significantly associated with malignancy were tumor size or presence in main pancreatic duct. In 30 resected patients after a mean follow-up of 60 months, tumor recurrence had occurred in 2 cases of invasive carcinoma that infiltrated into the extrapancreatic organ. The overall actuarial 5-year and 10-year survival was 83% and 62%, respectively. CONCLUSIONS: IPMT has a favorable prognosis after adequate resection. Despite slow growth, IPMT has an obvious malignant potential and a poor prognosis when invasive carcinoma has developed. Early recognition and pancreatectomy is the mainstay of treatment for IPMT.     

Outcome after surgical resection of intraductal papillary and mucinous tumors of the pancreas

OBJECTIVE: Treatment of intraductal papillary and mucinous tumors of pancreas (IPMT) usually requires surgery. The objective of this study was to evaluate the risk of recurrence in patients after surgery according to the histological nature of the neoplasm and the type of surgery. METHODS: The outcome of 45 patients who underwent partial pancreatectomy (n = 35) or total pancreatectomy (n = 10) for IPMT was studied according to the nature of the neoplasm (invasive carcinoma or noninvasive neoplasm), type of surgery (partial or total pancreatectomy), and lymph nodes status. RESULTS: The overall 3-yr actuarial survival rate was 83%. Death occurred in seven of 20 (35%) patients with invasive carcinoma and in one of 26 (4%) patients with noninvasive tumors (p<0.05). There were two recurrences in the seven patients with noninvasive neoplasm who underwent partial pancreatectomy with involved resection margins, and none in the 13 patients with disease-free margins. In patients with invasive carcinoma, there was one recurrence after total pancreatectomy, six after partial pancreatectomy with disease-free margins and six after partial pancreatectomy with involved margins. In patients with invasive carcinoma, total pancreatectomy and the absence of lymph nodes involvement were independently associated with a low risk of recurrence. CONCLUSIONS: IPMT may be managed as follows: 1) in patients with noninvasive neoplasms, partial pancreatic resection should be guided by frozen section examination until disease-free margins are obtained; and 2) in patients with invasive carcinoma, total pancreatectomy seems most likely to cure the patient, but should be discussed according to the general status and the age.     

Case of intraductal papillary mucinous tumor (noninvasive adenocarcinoma) of the pancreas resected 27 years after onset

Summary A case of intraductal papillary mucinous tumor (IPMT) of the pancreas resected 27 yr after onset is presented. In March of 1997, a 71-yr-old man was admitted to our hospital with a complaint of severe epigastric pain. He had initially undergone endoscopic retrograde pancreatography (ERP) in April 1971 in our hospital and the patient had been followed up for pancreatografic changes for 26 yr. Dilatation of the main pancreatic duct gradually progressed during follow-up, and the filing defect owing to the tumor became demonstrable. On admission, ERP revealed diffuse dilatation of the main pancreatic duct, which was 20 mm in diameter, and the filling defect of 35 mm in diameter. We diagnosed this patient as having an IPMT of the pancreas. Considering his general condition, pancreatic segmentectomy was carried out, and the postoperative course was favorable. Histological findings were compatible with those of noninvasive papillary adenocarcinoma. This is a precious case for studying the natural history of intraductal papillary tumor of the pancreas and to evaluate the application of surgery, because the biologic behavior of this tumor is much less aggressive than that of pancreatic ductal cell carcinoma.     

Total pancreatectomy for intraductal papillary-mucinous tumor of the pancreas: reappraisal of total pancreatectomy

BACKGROUND/AIMS: Total pancreatectomy is rarely performed as the treatment of pancreatic carcinoma because of markedly impaired quality of life and poor prognosis. Intraductal papillary-mucinous tumor (IPMT) of the pancreas is characterized by extensive intraductal spread and favorable outcome even in its invasive stage. The role of total pancreatectomy was reappraised in the treatment of IPMT. METHODOLOGY: A total of five Japanese patients with IPMT underwent total pancreatectomy and their clinical follow-up data were reviewed. RESULTS: Total pancreatectomy was performed due to massive involvement of the entire pancreas in two patients, positive surgical margins on frozen section in one, benign IPMT with concomitant pancreatic cancers in one and recurrent IPMT in the remnant pancreas after distal pancreatectomy for IPMT in the other. Three of them underwent total pancreatectomy of the Whipple type, another underwent total gastrectomy and the other underwent the pylorus-preserving method. Surgical margins were negative by histology and no lymph node metastases were evident. Two patients had severe infection including liver abscess in one and pneumonia in the other. The former died on postoperative day 82 and the latter was controlled by medical treatment and discharged on postoperative day 73. The other three patients had an uneventful postoperative course and were discharged from 29 to 62 days after the operation. Long-term follow-up of the four patients revealed that three patients had hypoglycemic attacks, two diabetic retinopathy and two fatty liver. The four patients were doing well from 683 to 4,140 days after the operation without signs of recurrence. CONCLUSIONS: Total pancreatectomy would be indicated as a treatment of benign or malignant IPMT with extensive involvement when patients' condition permits and gives a chance of cure, although careful long-term medical care and follow-up are essential.     

Intraductal papillary-mucinous tumors of the pancreas: Clinicopathologic features, outcome, and nomenclature. Members of the Pancreas Clinic, and Pancreatic Surgeons of Mayo Clinic

BACKGROUND & AIMS: Intraductal papillary-mucinous tumor (IPMT) of the pancreatic ducts is increasingly recognized. This study investigated if clinical, imaging, or, histological features predicated outcome, formulated a treatment algorithm, and clarified relationships among IPMT, mucinous cystic neoplasms of the pancreas (MCN), and chronic pancreatitis. METHODS: The medical records, radiographs, and pathological specimens of 15 patients with IPMT (dilated main pancreatic duct or branch ducts with mucin overproduction) who were evaluated between October 1983 and January 1994 were reviewed. RESULTS: One patient had hepatic metastases. Fourteen underwent an operation (6 distal pancreatectomy, 4 total pancreatectomy, and 4 pancreaticoduodenectomy); all had dysplastic intraductal epithelium and chronic pancreatitis, whereas 3 had invasive adenocarcinoma. After a median of 25 months, 10 patients were alive; 3 of 4 with malignant and 2 of 11 with benign IPMT died (P < 0.05). Patients with or without carcinoma had similar clinical and radiographic features. A clinical diagnosis of chronic pancreatitis had been made in 9 patients with benign IMPT and in none with malignant IPMT (P < 0.05). CONCLUSIONS: IPMT is a dysplastic and likely precancerous lesion that is frequently diagnosed as chronic pancreatitis and is separate from MCN. Because it is not possible to distinguish noninvasive from invasive IPMT preoperatively, complete surgical excision of the dysplastic process is our treatment of choice whenever appropriate. (Gastroenterology 1996 Jun;110(6):1909-18)     

Long-term follow-up of intraductal papillary adenoma of the pancreas

Intraductal papillary mucinous tumors of the main pancreatic duct are often considered to be premalignant or malignant, and therefore surgical resection is recommended. We report two autopsy cases of intraductal papillary mucinous tumor of the pancreas following long-term observation. The first patient was an 84-year-old man with early gastric cancer treated by endoscopic mucosectomy. The second patient was a 77-year-old man with hepatocellular carcinoma treated by percutaneous pure ethanol injection and transarterial embolization. In both patients, endoscopic retrograde pancreatography showed a diffusely dilated main pancreatic duct, with intraductal filling defects expressing mucus, as well as dilated side branches. Obvious intramural nodules were not detected. Due to their advanced age and personal requests, both patients were managed conservatively and followed nonoperatively. In the first patient, serial pancreatograms showed progression of the pancreatic duct dilatation. Both patients died of gastric cancer, the first patient 7¹/₂ years and the second, 10 years after first presentation, respectively. Autopsies revealed extensive intraductal papillary adenoma throughout the dilated mucus-filled main pancreatic duct. However, there was no evidence of progression to adenocarcinoma. Based on these observations, we suggest that, in patients with intraductal papillary mucinous tumor of the pancreas without obvious intramural nodules, even if the tumor is in the main pancreatic duct, pancreatectomy may not be mandatory, particularly in the elderly. Received: March 21, 2001 / Accepted: July 6, 2001 Reprint requests to: T. Kamisawa     

Intraductal papillary mucinous neoplasm of the pancreas with a bifid pancreatic duct

A bifid pancreatic duct presenting a major bifurcation in the main pancreatic duct is one of the anatomical variations of the pancreatic ducts. We encountered a 71-year-old female with a 5-cm-diameter branch duct intraductal papillary mucinous neoplasm of the pancreas in whom preoperative endoscopic retrograde pancreatography demonstrated an anomalous bifurcation of the main pancreatic duct at the body of the pancreas. We performed a distal pancreatectomy, instead of a middle pancreatectomy, with a cutting line at the downstream pancreas to the duct bifurcation point. Intraoperative ultrasonography was useful to confirm the exact location of the pancreatic duct bifurcation as well as the tumor extension. The procedure resulted in a favorable outcome without any postoperative complications. Although a bifid pancreatic duct is an unusual anomalous condition, this case should alert surgeons to be aware of such anatomical variants when performing pancreatic resection, otherwise, incurable pancreatic complications may occur postoperatively.     

Intraductal papillary mucinous tumor of the pancreas: computerized tomography and magnetic resonance imaging features

The aim of this study was to analyze the computerized tomography (CT) and magnetic resonance imaging (MRI) features of intraductal papillary mucinous tumor (IPMT) of the pancreas. The cases of eight patients with pathologically proven IPMT (1 papillary hyperplasia, 7 adenocarcinoma) of the pancreas were retrospectively reviewed. There were five men and three women with ages ranging from 42 to 82 years. Imaging studies included six thin-section dynamic CT scans, seven MRI scans, one MR cholangiopancreatography scan, and two endoscopic retrograde cholangiopancreatography scans. There was only one benign IPMT, which presented as a unilocular cyst in the pancreatic body with no mural nodules and no dilatation of the main pancreatic duct (MPD). All seven patients with malignant IPMT had multilocular cysts with papillary projections in the pancreatic head and/or uncinate process accompanied by dilated MPD (5 diffuse, 2 segmental). Communication between the cystic lesions and the MPD were evident in all seven patients. One patient had small mural nodules in the branch ducts of the pancreatic body and five had a bulging papilla with a patulous orifice. A mass effect resulting in biliary obstruction was shown in one patient. One patient had a ruptured cyst with mucin leakage into the right anterior pararenal space following sono-guided aspiration. In conclusion, the main imaging feature of IPMT in our patients was a multilocular cyst with papillary projections located in the pancreatic head and uncinate process. Although CT and MRI cannot differentiate mucin content from pancreatic juice, communication between the cystic lesion and the dilated MPD and a bulging papilla with a patulous orifice are characteristics of IPMT.     

Mucin-Producing Tumor of the Pancreas: A Unique Clinical Entity

We report our experience with nine patients with "mucin-producing tumor of the pancreas," in which abundant mucin secreted by the tumor cells played a major role in the characteristic alterations of the pancreatic duct system. Four of nine patients presented with pancreatitis. Ultrasound and computed tomography demonstrated a well-defined cystic mass and dilated main pancreatic duct. Endoscopic retrograde pancreatography showed ductectatic character, i.e., diffuse dilatation of main duct and/or cystic dilatation of the branch ducts with filling defects of mucin. Ultrasound proved to be a good screening test. However, the diagnosis was confirmed on endoscopic retrograde pancreatography. Nine of our cases had no peripancreatic invasion or metastasis, resulting in a good prognosis after pancreatectomy. Mucin-producing tumor of the pancreas is a unique clinical entity that should be distinguished from "common" pancreatic carcinomas, and a favorable prognosis can be expected after surgical operation.     

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 3 mm in all adenoma or carcinoma cases, while the percentage of hyperplasia less than 3 mm 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.     

Subtotal duodenopancreatectomy for pancreatic duct, distal bile duct and periampullary carcinoma: short- and long-term results

Ninety patients with pancreatic duct, distal bile duct, and ampullary carcinoma underwent pancreatic resection. Following a standard policy of resection based on surgical findings, all the patients who had resection first underwent subtotal extended pancreatectomy (n = 68) and if they were considered not to fulfill the criteria for this operation, total pancreatectomy (n = 22). Thus, 68 of the 90 patients (72%) were managed with subtotal pancreatic resection irrespective whether they had ampullary, pancreatic duct, or distal common bile duct carcinoma. On the basis of our results, subtotal duodenopancreatectomy is regarded as the method of choice for many patients with pancreatic duct, distal bile duct, or ampullary carcinoma.     

WHAT KIND OF BENEFIT DO WE EXPECT FOR PERORAL PANCREATOSCOPY IN THE DIAGNOSIS OF INTRADUCTAL PAPILLARY MUCINOUS TUMOR OF THE PANCREAS?

Intraductal papillary mucinous tumor (IPMT) of the pancreas is characterized by slow growth and a relatively favorable prognosis, however, invasive cancer originating in an IPMT is associated with a poor prognosis. Although various parameters in imaging modalities have been advocated to differentiate between benign IPMN and malignant ones, it is not easy to obtain definite diagnosis based on these parameters. Peroral pancreatoscopy (POPS) allows a clear and direct visualization of the pancreatic duct, providing useful information regarding tumor nature in IPMT. The authors have studied the usefulness of POPS in the diagnosis of IPMT. Nevertheless, its usefulness is not necessarily widely accepted and the significance of POPS is still controversial. In this review, the authors intended to address the diagnostic value of POPS and to clarify its role in the diagnosis of IPMT. The authors think treatment of IPMT can be improved by introducing POPS because the determination of surgical procedure as well as the area of resection based on the preoperative diagnosis of the involvement of the main pancreatic duct and branch duct is inevitable.     

Clinicopathologic study of intraductal papillary-mucinous tumors and mucinous cystic tumors of the pancreas

BACKGROUND/AIMS: We analyzed clinicopathologic and imaging findings of intraductal papillary-mucinous tumors (IPMTs) and mucinous cystic tumors (MCTs) of the pancreas to evaluate the difference between IPMTs and MCTs, and to identify the signs indicative of malignancy in IPMTs. METHODOLOGY: Clinicopathological features of 20 patients with IPMT and six patients with MCT of the pancreas were studied. RESULTS: The patients with IPMT comprised 16 males and four females with a mean age of 62.9 years. Eighty percent of IPMTs were located in the pancreatic head, and the mean tumor size was 38.6mm. Recurrence was observed in one patient, who died of IPM adenocarcinoma. In contrast, all patients with MCT were females, with a mean age of 53.0 years. None of the MCTs arose in the pancreatic head, and the mean tumor size was 42.7mm. One patient died of MC adenocarcinoma, but all of the others survived without recurrence. The difference in gender, location of the tumor, and connection to the pancreatic duct reached statistical significance between IPMTs and MCTs. A significant connection to the pancreatic duct and high level of serum carbohydrate antigen 19-9 (CA19-9) was observed in the adenocarcinoma and moderate dysplasia groups of IPMT. CONCLUSIONS: The main duct type and an elevation of serum CA19-9 level suggested malignancy in IPMTs.     

Long-term follow up results of intraductal papillary mucinous tumors of pancreas

BACKGROUND AND AIM: Intraductal papillary mucinous tumor (IPMT) of the pancreas can be divided into three clinically distinct subtypes: main duct type, branch duct type and mixed type. Although it has been reported that the branch duct type IPMT is less invasive than the main duct type IPMT, we experienced a number of branch duct type IPMT having a poor prognosis. In the present study we surveyed the survival and recurrence rates according to the subtypes. METHODS: Sixty-seven IPMT cases were studied to investigate clinical behavior according to the duct types. Diagnostic findings and late results of treatment were reviewed in 27 cases of the main duct type IPMT and in 35 cases of the branch duct type IPMT. RESULTS: There was no statistically significant difference in the survival analysis between the main duct type IPMT and the branch duct type IPMT (P = 0.93). Seven patients (25.9%) died among the main duct type IPMT while six patients (17.1%) died among the branch duct type IPMT (P = 0.36). Tumor recurrence was noticed in four patients (18.1%) among 22 operated main duct type IPMT and in two patients (6.9%) among 29 operated branch duct type IPMT (P = 0.35). CONCLUSION: The long-term follow up result of the branch duct type IPMT is similar to that of the main duct type IPMT. Therefore, it is not safe just to monitor the branch duct type IPMT without operation. Surgery, whenever possible, is clearly the gold standard for treatment of IPMT, regardless of duct type.     

IDUS IN THE DIAGNOSIS OF IPMT

Intraductal papillary mucinous tumor of the pancreas (IPMT) is considered as having low‐grade malignant potential, and malignancy is not infrequent. Therefore, accurate diagnosis is indispensable for appropriate patient care. IPMT is classified mainly into two categories based on the distribution of tumor, the main duct type and the branch duct type. In the diagnosis of IPMT, there are four important points: differentiation of IPMT from other pancreatic pathologies; differentiation of malignancy from benign lesions; evaluation of tumor extent along the MPD; and investigation of duct cell carcinoma coexistent with or derived from IPMT. IPMT should be distinguished from chronic pancreatitis, ductal adenocarcinoma, or cystic neoplasms. IPMT often requires pancreaticoduodenectomy for cure, but such invasive surgery should be avoided in patients with benign hyperplasia. Mural nodules in the MPD can be clearly visualized by intraductal ultrasonography (IDUS). Measurement of the height of the tumor mass by IDUS is useful in distinguishing benign from malignant IPMT. Intraductal spread of IPMT along the MPD is demonstrated by IDUS as irregular thickening of the MPD wall. To achieve a tumor‐free margin in surgery, evaluation by IDUS of the extent of the tumor along the MPD is important. The expected accuracy of IDUS in the diagnosis of invasive IPMT is reportedly over 90%.     

Surgical treatment for serous cystadenoma of pancreas--segmental pancreatectomy or conventional resection?

BACKGROUND/AIMS: Benign tumors located in the neck or body of the pancreas are usually removed by left pancreatectomy or pancreaticoduodenectomy when enucleation is too risky for possible damage of the main pancreatic duct. But standard pancreatic resection has its potential operative risk and may result in loss of pancreatic parenchyme and cause impairment of pancreatic function. The aim of this study was to compare the results of segmental pancreatectomy, a limited resection of the mid-portion of the pancreas, and traditional extensive pancreatic resection, i.e. distal pancreatectomy or pancreaticoduodencetomy in patients with serous cystadenoma of the pancreas. METHODOLOGY: From January 1989 to February 2002, 19 patients with serous cystadenoma of the pancreas treated with pancreatic resection were reviewed. Among them segmental pancreatectomy was performed in 5 cases, distal pancreatectomy was carried out in 11, pancreaticoduodenectomy in 2 and total pancreatectomy in one patient. RESULTS: Operation time was significantly longer in segmental pancreatectomy than in distal pancreatectomy (P<0.001) and a greater blood loss was also noticed in the conventional resection. There was no operative mortality and the postoperative hospital stays were not different in any group. A higher rate of pancreatic fistula was encountered in segmental pancreatectomy, however all of the fistulas sealed off after conservative treatment. A trend of higher chance of developing postoperative diabetes was noticed in the conventional resection. Except for the patient who underwent total pancreatectomy no patient developed frank steatorrhea during long-term follow-up. CONCLUSIONS: Segmental pancreatectomy is a safe and technically feasible procedure in selected patients with benign pancreatic tumor. This procedure carries a similar surgical risk as that of standard operation, but avoids extensive pancreatic resection which in turn may preserve more pancreatic functions.