Role of frozen section assessment for intraductal papillary and mucinous tumor of the pancreas

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas include a spectrum of dysplasia ranging from minimal mucinous hyperplasia to invasive carcinoma and are extensive tumors that often spread along the ductal tree. Several studies have demonstrated that preoperative imaging is not accurate enough to adapt the extent of pancreatectomy and have suggested routinely using frozen sectioning (FS) to evaluate the completeness of resection and also to check if ductal dilatation is active or passive, in order to avoid an excessive pancreatic resection. Separate main duct and branch duct analysis is needed due to the difference in the natural history of the disease. FS accuracy averages 95%. Eroded epithelium on the main duct, severe ductal inflammation mimicking dysplasia and reactive epithelial changes secondary to obstruction can lead to inappropriate FS results. FS results change the planned extent of resection in up to 30% of cases. The optimal cut-off leading to extend pancreatectomy is not consensual and our standard option is to extend pancreatectomy if FS reveals: (1) at least IPMN adenoma on the main duct; or (2) at least borderline IPMN on branch ducts; or (3) invasive carcinoma. However, the decision to extend resection must be taken after a multidisciplinary discussion since it does not exclusively depend on the FS result but also on age, general condition and expected prognosis after resection. The main limitation of using FS is the existence of discontinuous ("skip") lesions which account for approximately 10% of IPMN in surgical series and can lead to reoperation in up to 8% of cases.     

Repeated Pancreatectomy after Pancreatoduodenectomy

Background When pancreatic duct dilatation is found in the patient having undergone pancreatoduodenectomy (PD), observation is chosen in most cases. Similarly, recurrent tumor in the remnant pancreas of invasive ductal carcinoma (IDC) of the pancreas is seldom indicated for resection. We have aggressively performed repeated pancreatectomy for these cases and obtained good results. Methods Repeated pancreatectomy after PD was performed for three types of circumstances: (1) pancreatodigestive anastomotic stricture; (2) neoplasm after intraductal papillary mucinous neoplasm (IPMN); and (3) recurrence of IDC of the pancreas. Results Resection of anastomosis and reanastomosis was performed for pancreatodigestive stricture in four patients. Symptoms derived from pancreatitis in three patients resolved by the second operation and did not recur during follow-up. None of the four patients required pancreatic enzyme substitution because of clinically overt malabsorption, and the defecation frequency of the four patients was within twice a day. Mild diabetes mellitus has been identified in only one patient who had diabetes mellitus before the second surgery. Completion pancreatectomy and pancreatic tail resection was performed for recurrence in two patients and IDC in one patient, respectively, after PD for IPMN. Intrapancreatic recurrences of IPMN in two patients existed in the main pancreatic ducts. As CT revealed pancreatic duct dilatation but not intraductal tumors, recurrences were not correctly diagnosed before the second operation. Completion pancreatectomy was performed for recurrence of IDC in two patients. One patient who underwent completion pancreatectomy for recurrence of IDC survived 66/44 months after the first/second operation. Conclusion Repeated pancreatectomy should be performed for patients with pancreatodigestive anastomotic stricture to preserve remnant pancreatic function and for patients with neoplasm or pancreatic duct dilatation after PD for IPMN, and repeated pancreatectomy for recurrence of IDC might be indicated for selected patients.     

Intraductal papillary mucinous neoplasm of the pancreas: clinical characteristics and treatment outcomes of 118 consecutive patients from a single center

Background/Purpose Appropriate surgical treatment strategies based on clinicopathological findings are unavailable for intraductal papillary mucinous neoplasm (IPMN) of the pancreas. We investigated the clinical features of pancreatic IPMN in a single-center database in order to design an optimal surgical strategy. Methods The medical records of 118 consecutive patients who had undergone surgical resection between August 1994 and December 2004, in whom IPMN was histologically confirmed, were reviewed retrospectively for radiological and pathological findings. Results Most of the invasive carcinomas in these patients were detected as the main-duct type (88.5%). The type of tumor (main-duct type vs branched-duct type), the tumor size, and the dilated duct size were significant predictive factors associated with malignancy. The relative risk of malignancy was greatest at 13-mm or more ductal dilation in the main-duct type (Odds ratio, 4.1), at 35-mm or more tumor size (Odds ratio, 7.6), and for main-duct type (Odds ratio, 3.9). Major pancreatic resections such as total pancreatectomy and pancreatoduodenectomy were performed in 14.5% and 69% of the patients, respectively. There was a 19.5% rate of incomplete resection, with these patients having a positive resection margin. However, significant recurrence did not occur in patients with a benign IPMN lesion which remained at the resection margin. The overall postoperative survival rate at 5 years was 98.2% for benign IPMN and 65.3% for malignant IPMN. Conclusions Function-preserving strategies, based on the clinical status of the patient, are necessary in order to avoid possible severe metabolic complications following extended pancreatectomy in patients with benign IPMN because of the low recurrence rate and good prognosis of this entity, irrespective of margin status.     

Characterization of K-ras gene mutations in association with mucinous hypersecretion in intraductal papillary-mucinous neoplasms

Background/Purpose Intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas have a favorable prognosis. However, invasive ductal carcinomas of the pancreas show a rapid progression. The aim of this study was to investigate gene mutations in pure pancreatic juice from IPMN patients and to define these genetic mutations in relation to the histopathological and clinical features of IPMNs. Methods Twenty-two patients with IPMN, 21 patients with ductal carcinoma, and 20 patients with normal pancreas or chronic pancreatitis were recruited for this study. We measured the main pancreatic duct’s largest diameter and the maximum size of a dilated branch was assessed by ultrasonography or endoscopic ultrasonography. Pure pancreatic juice was collected and was investigated for K-ras, p16, and p53 mutations. Results Mutant K-ras gene was detected in 13 of the 22 patients (59.1%) with IPMNs. Different kinds of mutations were detected in the same patient in 4 cases. In the 13 patients with mutant K-ras gene, the diameter of the most dilated part of the main pancreatic duct was 2–8 mm (average, 4.5 mm) and in 7 patients with wild-type K-ras gene, the diameter was 2–5 mm (average, 2.7 mm). There was a significant difference in the diameter of the main pancreatic duct between patients with and without the mutant K-ras gene (P = 0.0323). Conclusions The incidence of K-ras mutation may be associated with the hypersecretion of mucin.     

Intraductal papillary mucinous neoplasms of the pancreas: an analysis of clinicopathologic features and outcome

OBJECTIVE: To define the natural history of resected intraductal papillary mucinous neoplasms (IPMN) of the pancreas and to identify clinical and pathologic prognostic features. SUMMARY BACKGROUND DATA: IPMN of the pancreas is a recently described pancreatic tumor. Because of a limited number of cases, prognostic factors and the natural history of resected cases have not been well defined. MATERIALS AND METHODS: A prospective pancreatic database was reviewed to identify patients with IPMN who were surgically managed. Pathologic re-review of each case was performed, and the clinicopathologic features were examined. Log rank and chi2 analysis were used to identify factors predictive of survival and recurrence. RESULTS: Over a 17-year period, 63 patients were identified. One patient was unresectable, 6 (10%) underwent a total pancreatectomy, and 56 (89%) had a partial pancreatectomy. Invasive carcinoma was present in 30 patients (48%). Transection margins were involved with atypia or carcinoma in 32 patients (51%). The median follow-up for survivors was 38 months. Disease-specific 5- and 10-year survival were 75% and 60%, respectively. Significant predictors of poor outcome included presentation with elevated bilirubin, presence of invasive carcinoma, increasing size and percentage of invasive carcinoma, histologic type of invasive carcinoma, positive lymph nodes, and vascular invasion. The presence of atypia or carcinoma in situ at the ductal resection margin was not associated with a poor outcome. CONCLUSIONS: Overall, IPMN has a favorable prognosis. Poor outcome in a subset of patients is largely the result of the presence, extent, and type of an invasive component, lymph node metastases, and vascular invasion.     

Ductal branch-oriented minimal pancreatectomy: Two cases of successful treatment

Two patients with intraductal papillary-mucinous adenoma of the pancreas were successfully treated by ductal branch-oriented minimal pancreatectomy. We propose this novel less invasive ductal branch-oriented pancreatectomy, as indicated for benign ductal ectasia of the pancreas. The cystically dilated branch duct is identified by intraoperative ultrasonography, intraoperative balloon pancreatography, and injection of indigocarmine into the cyst. The cystically dilated branch is resected from the surrounding pancreas together with minimal removal of the pancreatic parenchyma. The communicating duct and cutting margins are tightly ligated to prevent pancreatic juice leakage and fistula. A drainage tube is placed in the main pancreatic duct whenever possible. Histopathologic examination of the transected branch duct is necessary to check for mucosal extension of dysplastic epithelium. This ductal branch-oriented minimal pancreatectomy is the least invasive pancreatectomy and a suitable operation for branch-type ductal ectasia of the pancreas, which is usually benign. Received for publication on Jan. 5, 1998; accepted on April 3, 1998     

Dorsal pancreatectomy: An embryology-based resection

In a 45-year-old man with acute pancreatitis and recent onset of diabetes mellitus, intraductal papillary mucinous neoplasm (IPMN) associated with pancreas divisum was found. There were no arguments for an invasive component in the IPMN lesions, which seemed to involve nearly all the dorsal pancreas. Re-section of only the dorsal pancreas was performed with division of the pancreas at the internal side of the duodenum and at the anterior edge of the common bile duct. The gastroduodenal artery was preserved resulting in good vascularization of both common bile duct and proximal duodenum. Postoperative course was marked by a transient pancreatic fistula. Definitive pathological examination revealed nonin-vasive IPMN involving several branch ducts and partially the cephalic dorsal duct, with an 8 mm tumor-free segment from the transection level. Twelve months after resection, the patient had normal gastro-intestinal function with neither clinical exocrine insufficiency nor uncontrolled diabetes. Postoperative magnetic resonance imaging revealed no signs of recurrence in the ventral pancreas. In patients with pancreas divisum, dorsal pancreatectomy can be proposed for noninvasive IPMN involving only the dorsal pancreas to avoid drawbacks of total duodenopancreatic resection.     

Pancreatobiliary fistula associated with an intraductal papillary-mucinous pancreatic neoplasm manifesting as obstructive jaundice: Report of a case

We report a pancreatobiliary fistula caused by an intraductal papillary-mucinous pancreatic neoplasm (IPMN), manifesting as obstructive jaundice. Computed tomography showed dilatation of the bile duct and main pancreatic duct, with multiple cystic masses in the head of the pancreas. Endoscopic retrograde pancreatocholangiography showed a patulous papilla with mucin secretion. Contrast enhancement outlined amorphous material obstructing the lower part of the common hepatic duct. Pancreatogram and magnetic resonance cholangiopancreatography showed diffuse dilatation of the main pancreatic duct and side branches without communication with the adjacent organs or duct. We performed pancreaticoduodenectomy for IPMN of the pancreatic head and a tumor-like lesion in the lower common bile duct (CBD). Macroscopically, impacted thick mucus protruded into the CBD from the pancreas via a pancreatobiliary fistula. Histologic examination revealed a pancreatobiliary fistula caused by intraductal papillary-mucinous carcinoma of the pancreas with mucin hypersecretion, an adenoma without interstitial infiltration, and isolated implantation of an IPMN in the bile duct mucosa around the fistula.     

Outcomes after pancreatectomy for intraductal papillary mucinous neoplasms of the pancreas: an institutional experience

PURPOSE: To evaluate the experience with pancreatectomy for intraductal papillary mucinous neoplasm (IPMN) at a single academic institution. METHODS: A prospective pancreatic database was reviewed and identified 43 patients with IPMN who were managed operatively. Clinicopathologic features and predictors of outcome were examined. The World Health Organization pathologic classification of IPMN was utilized. RESULTS: IPMN was diagnosed in 21% of patients who underwent pancreatic resection for solid or cystic mass lesions. Ninety-five percent of patients were symptomatic. Patients were managed with total pancreatectomy, pancreaticoduodenectomy, distal pancreatectomy, central pancreatectomy, or enucleation. Nine patients had adenomas, 14 had borderline neoplasms, 10 had carcinoma in situ, and 9 had invasive carcinoma. Overall, 23 patients (53%) had lesions with main duct involvement. Frozen section transection margins were positive for malignancy in 2 patients. With a mean follow-up of 17 months, the 5-year disease-specific survival for patients with main duct involvement was 67%. The 5-year disease-specific survival for patients with benign lesions was 100%, and 61% for patients with malignant lesions (P = .02). The presence of symptoms, increased CA 19-9, and tumor size were not predictive of malignancy. Increased serum bilirubin concentrations were predictive of malignancy (P = .03). Main duct involvement was also associated with malignancy (P < .02). CONCLUSIONS: Cancer is found in 65% of patients with IMPN involving the main duct. Based on our data, patients with symptomatic, main duct involvement, especially those with an increased serum bilirubin, should be offered resection. Alternatively, patients with side branch IPMN may be managed conservatively.     

Noninvasive intraductal papillary mucinous neoplasm with para-aortic lymph node metastasis: report of a case

Intraductal papillary mucinous neoplasms (IPMNs) with an invasive carcinoma component are categorized as minimally invasive or invasive. The prognosis after resection of minimally invasive IPMNs has been reported to be similar to that after resection of noninvasive IPMNs. We report a case of noninvasive branchduct IPMN with multiple lymph node metastases, including para-aortic node involvement, treated successfully by distal pancreatectomy with lymph node dissection. The patient, a 72-year-old man, had two multilocular cysts in the pancreatic body, 22 mm and 14 mm in diameter, respectively, communicating with the main pancreatic duct. The primary tumor and nodal metastases had similar patterns of mucin expression. The primary tumor contained a region of carcinoma in situ (CIS) without histological evidence of stromal invasion; thus, it was diagnosed as minimally invasive carcinoma. We report this case to emphasize two important points: first, even small branch-duct IPMNs without any indications for resection can have a component of CIS or more advanced disease; and second, even branch-duct IPMNs without any apparent invasive component can be aggressive and spread to the lymph nodes. Therefore, nodal status should be assessed carefully in every patient, even if the primary IPMN is not advanced.     

Laparoscopic distal pancreatectomy for intraductal papillary mucinous neoplasm-associated pancreatic cancer: A case report

Introduction and importanceIntraductal papillary mucinous neoplasm (IPMN) of the pancreas is often found incidentally during examination for other diseases. In addition to the risk of malignant transformation, patients with IPMN are at risk of developing pancreatic cancer. We report a case of pancreatic tail cancer that developed separately from a preexisting IPMN after minimally invasive esophagectomy for cancer of the esophagogastric junction and was resected successfully by laparoscopic distal pancreatectomy.Case presentationA 72-year-old man underwent thoracoscopic and laparoscopic esophagectomy for esophagogastric junction cancer. He had undergone surgery for ascending colon cancer 20 years ago. At that time, IPMN was confirmed in the pancreatic body by a preoperative examination. Computed tomography was regularly performed for postoperative work-up and follow-up of the IPMN, and a solid lesion with cystic components was detected in the pancreatic tail 9 months after the operation. On detailed examination, pancreatic ductal adenocarcinoma concomitant with IPMN, accompanied by a retention cyst, was considered. Laparoscopic distal pancreatectomy was successfully performed after neoadjuvant chemotherapy. Pathological diagnosis of the lesion in the pancreatic tail was of an invasive intraductal papillary mucinous carcinoma (ypT3ypN0yM0 ypStageIIA).Clinical discussionIf an IPMN is detected during preoperative examination for malignancies of other organs, careful follow-up is necessary due to the high risk of pancreatic cancer development. Furthermore, initial operation with minimally invasive surgery may reduce adhesion and facilitate subsequent surgeries.ConclusionWe have provided evidence that supports the importance of a careful follow-up of IPMNs, even if they are low risk.     

Intraductal papillary mucinous neoplasm of the pancreas associated with neuroendocrine tumor: A case report

IntroductionIntraductal papillary mucinous neoplasm is an uncommon cystic tumor of pancreas that can be associated with ductal adenocarcinoma. Coexistence of pancreatic IPMN and neuroendocrine tumor is very rare. Here, we report the imaging features of mixed type intraductal papillary mucinous neoplasia of the pancreas with high grade dysplasia together with neuroendocrine carcinoma and perform review of the literature.PresentationA 68-year old patient has been evaluated for possible IPMN that was suspected during ultrasound. MRI revealed main and side branch duct dilatations. At the head, a contrast enhancing nodular lesion was identified. Due to the presence of high risk stigmata according to guidelines, surgery was performed. Histopathological examination revealed an unusual association, including mixed type IPMN and neuroendocrine carcinoma.DiscussionThe concomitant occurrence of pancreatic IPMN and neuroendocrine tumor has been reported in case studies and brief reviews. Yet, the imaging findings and underlying molecular mechanisms of this entity has not been fully understood. In addition to this unusual association, pancreatic intraepithelial neoplasia was also detected in the present case. Although majority of neuroendocrine tumor associated IPMNs were reported to be having low grade dysplasia, our patient had high grade dysplasia. Further studies and reviews with larger groups are needed to establish imaging features and underlying molecular mechanisms of this rare association.ConclusionAlthough the major concern during work-up of IPMN is presence of associated pancreatic ductal adenocarcinoma, the possibility of neuroendocrine tumor, in the presence of a hypervascular solid foci on imaging studies should be kept in mind.     

Pylorus-preserving total pancreatectomy for an intraductal papillary-mucinous neoplasm of the pancreas

Background/Purpose Total pancreatectomy (TP) is rarely performed to treat invasive ductal carcinoma of the pancreas, due to the associated markedly impaired quality of life and poor prognosis after the resection. Intraductal papillary-mucinous neoplasm (IPMN) of the pancreas is characterized by extensive intraductal spread and a favorable outcome even when presenting at an invasive stage. We herein reappraise the role of pylorus-preserving total pancreatectomy (PPTP) as a viable alternative pancreatic resection modality for borderline and malignant IPMN. Methods A total of five patients with IPMN underwent PPTP and their clinical follow-up data were reviewed. Results TP was performed due to recurrent IPMN in the remnant pancreas after distal pancreatectomy in three patients and due to massive involvement of the entire pancreas in the others. All patients were treated by the pylorus-preserving method, while the spleen was also preserved in one patient. The surgical margins were negative and no metastasis to the resected lymph nodes was evident, based on histological examinations. One patient underwent a re-operation due to postoperative intraabdominal bleeding, while another patient required tubedrainage for left pleural effusion. Three of the four patients who underwent PPTP with a splenectomy experienced postoperative gastric ulcer, which were controlled by medication. One patient died due to suicide 16 months after the PPTP. All the others were doing well without recurrence at periods of 62 to 127 months after the PPTP. Conclusions PPTP is therefore considered to be indicated as an effective treatment for borderline or malignant IPMN with extensive involvement, when the patient's condition permits, in order to achieve complete resection of the IPMN.     

Intraductal papillary-mucinous neoplasms and mucinous cystic neoplasms of the pancreas differentiated by ovarian-type stroma

BACKGROUND: Intraductal papillary-mucinous neoplasms (IPMN) and mucinous cystic neoplasms (MCN) of the pancreas have similar clinicopathologic findings. This study was intended to clarify clinicopathologic characteristics in IPMNs and MCNs differentiated by ovarian-type stroma. METHODS: Medical records for 77 patients with pancreatic cystic neoplasms with mucin secretion were reviewed. Patients were divided into IPMN (n = 70) or MCN (n = 7) according to the presence of ovarian-type stroma, and clinicopathologic parameters were compared between groups. RESULTS: IPMNs consisted of 32 adenomas, 12 borderline neoplasms, 13 adenocarcinomas in situ, and 13 invasive adenocarcinomas; MCNs included 6 adenomas and 1 invasive adenocarcinoma. The mean age of IPMN patients (66 years) was significantly older than that of MCN patients (55 years). The male:female ratio in IPMN (53/17) was significantly greater (P < .001) than in MCN (0/7). The location of the pancreatic mass differed, with 76% 0f IPMNs occurring in the head, while 86% of MCNs occurred in the body or tail. Mass mean size was significantly smaller (28 mm vs 78 mm, P < .001), and mean diameter of the main pancreatic duct was larger (6.8 mm vs 3.1 mm, P < .001) in IPMN than in MCN. Patulous papilla was present in 44% (31/70) of IPMNs, but none was present in MCNs. Communication between the cyst and main pancreatic duct was more frequent in IPMNs (67/70) than in MCNs (1/7). Overall 5-year survival rates were 84% (IPMN) and 100% (MCN). CONCLUSIONS: Clinicopathologic differences between IPMN and MCN are much clearer when differentiated by presence of ovarian-type stroma. Favorable prognosis for both neoplasms is offered by complete resection.     

Uncinatectomy: a novel surgical option for the management of intraductal papillary mucinous tumors of the pancreas

An intraductal papillary mucinous tumor (IPMT) is a rare cystic lesion of the pancreas, comprising only 1% of all pancreatic exocrine neoplasms. The prognosis for these lesions is typically favorable as compared with invasive ductal carcinomas. Nevertheless, the management of IPMTs involves surgical resection due to their malignant potential. When located in the pancreatic head, the conventional treatment for IPMT is pancreatoduodenectomy. Some authors have advocated limited pancreatectomy for low-grade IPMTs of the pancreas, thereby decreasing the morbidity of more extensive resection. In this report, we describe our technique of minimal pancreatectomy, whereby the uncinate process and associated branch duct were completely extirpated while preserving remainder of the pancreatic head, duodenum, and pancreatic ducts. The case presented underscores the feasibility and advantages of minimal pancreatic resection in the management of such tumors.     

Current understanding of precursors to pancreatic cancer

Precursors to pancreatic cancer have been investigated for a century. Previous studies have revealed three distinct precursors, i.e. mucinous cystic neoplasm (MCN), intraductal papillary mucinous neoplasm (IPMN), and pancreatic intraepithelial neoplasia (PanIN), harboring identical or similar genetic alterations as does invasive pancreatic carcinoma. The current understanding of precursors to pancreatic cancer can be illustrated by progressive pathways from noninvasive MCN, IPMN, and PanIN toward invasive carcinoma. MCNs consist of ovarian-type stroma and epithelial lining with varying grades of atypia, and are occasionally associated with invasive adenocarcinoma. The epithelium of noninvasive IPMNs shows a variety of different directions of differentiation, including gastric, intestinal, pancreatobiliary (PB), and oncocytic types. IPMNs can also harbor varying grades of architectural and cytologic atypia. IPMNs confined to branch ducts are mostly the gastric type, and IPMNs involving the main ducts are often intestinal type, while PB and oncocytic types are rare. Small (<1 cm) IPMNs of the gastric type are not always morphologically distinguishable from low-grade PanINs. Mucin expression profiles suggest intestinal-type IPMNs progress to mucinous noncystic (colloid) carcinoma, while PB-type IPMNs progress toward ductal adenocarcinoma. It is a well-described paradigm that PanIN lesions progress toward ductal adenocarcinoma through step-wise genetic alterations. The activation of Hedgehog and Notch signaling pathways in PanIN lesions as well as in pancreatic adenocarcinoma suggest that developmental pathways may be disregulated during carcinogenesis of the pancreas. Further study is needed to elucidate the pathways from precursors toward invasive carcinoma of the pancreas.     

Intraductal Papillary Mucinous Neoplasms of the Pancreas: Effect of Invasion and Pancreatic Margin Status on Recurrence and Survival

Background The natural history and prognosis for patients with intraductal papillary mucinous neoplasms (IPMN) with and without invasion remain poorly defined. This study evaluated the outcome after pancreatectomy for IPMN according to the pancreatic transection margin status and the presence or absence of invasive carcinoma. Methods Data from a prospective pancreatic tumor database and medical records were reviewed for all patients who underwent pancreatic resection for IPMN at our institution between July 1990 and July 2003. Surgical specimens were re-reviewed by a single pathologist. Results IPMN was diagnosed in 35 (26%) of 137 patients who underwent pancreatic resection for cystic neoplasms. Invasive IPMN was confirmed in 13 (37%) of 35 patients. Noninvasive IPMN was found in 22 (63%) of 35 patients; pathology re-review changed the original diagnosis from invasive to noninvasive IPMN in 6 patients. Noninvasive IPMN was found at the final pancreatic margin in eight patients; none developed recurrent disease at a median follow-up of 34 months. Recurrent disease was identified in 7 (58%) of 13 patients with invasive IPMN and in none with noninvasive IPMN. The median overall survival was 22.9 and 84.9 months in patients with invasive and noninvasive IPMN, respectively (P = .0009). Conclusions Distinction between invasive and noninvasive IPMN is essential in estimating prognosis and determining the need for adjuvant therapy and the frequency of follow-up surveillance. Noninvasive IPMN, even if present at the pancreatic margin, was not associated with recurrent disease. In contrast, invasive IPMN was associated with early recurrence and short survival. Presented at the 57th Annual Cancer Symposium of the Society of Surgical Oncology, New York, New York, March 18–21, 2004.     

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.