Pancreatic mucinous cystic neoplasm defined by ovarian stroma: demographics, clinical features, and prevalence of cancer.

BACKGROUND & AIMS: Pancreatic mucin-producing cystic neoplasms are classified into 2 distinct entities: mucinous cystic neoplasm (MCN) and intraductal papillary mucinous neoplasm (IPMN). In previous studies, MCN often has been defined loosely and has not always been distinguished clearly from IPMN. Our aims were to determine the demographics, clinical features, and prevalence of invasive cancer in MCN defined by the presence of characteristic ovarian stroma. METHODS: By using the presence of ovarian stroma as a requisite criterion for diagnosis of MCN, a single pathologist, unaware of clinical information, identified 56 MCNs from 243 mucin-producing neoplasms resected at Mayo Clinic between 1986 and 2003. Medical records of the MCN patients were reviewed to obtain clinical and demographic data. RESULTS: Patients with MCN were almost exclusively (98%) women; we identified 1 man with a neoplasm containing ovarian stroma. The mean (+/-SD) age at resection was 48 +/- 15 years (84% < 60 y). Abdominal pain was the most common presenting symptom; 16% were asymptomatic. Most MCN (93%) were in the pancreatic body/tail region. Their median size was 5 cm (61% > or =5 cm). Histologically, 50 (89%) were adenomas, 2 (4%) had carcinoma-in-situ, and 4 (7%) had invasive cancer. None of the 22 MCNs <5 cm in size had invasive cancer. No patient with noninvasive disease had a recurrence after resection. CONCLUSIONS: MCN defined by ovarian stroma has a distinct demographic and clinical profile and a low prevalence of invasive cancer. These observations suggest that ovarian stroma should be used as the defining criterion for diagnosing MCN.     

Branch-duct intraductal papillary mucinous neoplasms: observations in 145 patients who underwent resection

BACKGROUND & AIMS: Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas arising in branch ducts are thought to be less aggressive than their main-duct counterparts, and guidelines for their conservative management were recently proposed. This study describes the combined experience of 2 tertiary centers with branch-duct IPMNs aiming to validate these recommendations. METHODS: A review of 145 patients with resected, pathologically confirmed, branch-duct IPMNs between 1990 and 2005 was conducted. RESULTS: Sixty-six patients (45.5%) had adenoma, 47 (32%) borderline tumors, 16 (11%) carcinoma in situ, and 16 (11%) invasive carcinoma. Median age was similar between benign and malignant subgroups (66 vs 67.5 years, respectively). Jaundice was more frequent in patients with cancer (12.5% vs 1.8%, respectively, P = .022) and abdominal pain in patients with benign tumors (45% vs 25%, respectively, P = .025). Forty percent of tumors were discovered incidentally. Findings associated with malignancy were the presence of a thick wall (P < .001), nodules (P < .001), and tumor diameter >or=30 mm (P < .001). All neoplasms with cancer were larger than 30 mm in size or had nodules or caused symptoms. After a mean follow-up of 45 months, the 5-year disease-specific survival for branch-duct IPMNs with noninvasive neoplasms was 100% and, for invasive cancer, was 63%. CONCLUSIONS: This large cohort of resected branch-duct IPMNs shows that cancer is present in 22% of cases and validates the recent guidelines that indicate absence of malignancy in tumors <30 mm, without symptoms or mural nodules.     

Pain sensation in pancreatic diseases is not uniform: The different facets of pancreatic pain

AIM: To systematically characterize specific pain patterns in the most frequent pancreatic diseases.METHODS: Pain in patients with chronic pancreatitis (n = 314), pancreatic cancer (n = 469), and other pancreatic tumors (n = 249) including mucinous (n = 20) and serous cystadenoma (n = 31), invasive (n = 37) and non-invasive intraductal papillary mucinous neoplasia (IPMN; n = 48), low stage (n = 18) and high stage neuroendocrine neoplasia (n = 44), and ampullary cancer (n = 51) was registered and correlated with clinicopathological data. Survival times were estimated by the Kaplan-Meier method. Patients alive at the follow-up time were censored. Survival curves were compared statistically using the log-rank test.RESULTS: Forty-nine point one percent of pancreatic cancer patients revealed no pain, whereas in chronic pancreatitis only 18.3% were pain free. In contrary, moderate/severe pain was registered in 15.1% in pancreatic cancer patients that was increased in chronic pancreatitis with up to 34.2%. Serous cystadenoma was asymptomatic in most cases (58.1%), whereas 78.9% of all mucinous cystadenoma patients suffered pain. In neuroendocrine neoplasia pain was not a key clinical symptom since 64% of low stage neuroendocrine neoplasia and 59% of high stage neuroendocrine neoplasia patients were pain free. Cancer localization in the pancreatic body and patients with malignant pancreatic neoplasms were associated with more severe pain. Tumor grading and stage did not show any impact on pain. Only in pancreatic cancer, pain was directly associated with impaired survival.CONCLUSION: Pancreatic pain depicts different patterns of abdominal pain sensation according to the respective pancreatic disorder and does not allow a unification of the term pancreatic pain.     

Intraductal papillary mucinous neoplasm of the biliary tract: a real disease?

Background:

Despite increasing numbers of reports, biliary tract intraductal papillary mucinous neoplasm (BT-IPMN) is not yet recognized as a unique neoplasm. The aim of the present study was to define the presence of BT-IPMN in a large series of resected biliary neoplasms.

Methods:

From May 1994 to December 2006, BT-IPMN cases were identified by reviewing pathology specimens of all resected cholangiocarcinomas and other biliary neoplasms when cystic, papillary or mucinous features were cited in pathology reports.

Results:

BT-IPMN was identified in 23 out of 253 (9%) specimens using the strict histopathological criteria of IPMN. The most common presenting symptom was abdominal discomfort which was present in 15 patients (65%). Only one of the original operative pathology reports used the term IPMN; 16 (70%) used the terms cystic, mucinous and/or papillary. BT-IPMN was isolated to non-hilar extra-hepatic ducts in 12 (52%), intra-hepatic ducts in 6 (26%) and hilar extra-hepatic ducts in 5 patients (22%). Carcinoma was found in association with BT-IPMN in 19 patients (83%); 5-year survival was 38% after resection.

Conclusion:

BT-IPMN occurs throughout the intra- and extra-hepatic biliary system and can be identified readily as a unique neoplasm. Broader acceptance of BT-IPMN as a unique neoplasm may lead to a better understanding of the pathogenesis of biliary malignancies.     

Outcome of the pancreatic remnant following segmental pancreatectomy for non-invasive intraductal papillary mucinous neoplasm

ObjectivesIntraductual papillary mucinous neoplasms (IPMNs) are often multifocal and involve the entire pancreas. Because of the morbidity associated with total pancreatectomy, surgeons will perform segmental pancreatectomy, resecting only the most ‘threatening’ IPMN lesion(s). We sought to determine whether the presence of residual IPMN following segmental pancreatectomy for non-invasive IPMN increases the risk for subsequent development of invasive pancreatic cancer and decreases survival.MethodsData on patients undergoing segmental resection of non-invasive IPMN during the period 1991–2010 at a high-volume academic institution were prospectively accrued.ResultsOf 243 patients who underwent segmental resection for IPMN, 191 (79%) demonstrated non-invasive pathology. Of these, 153 (80%) showed the absence and 38 (20%) the presence of residual IPMN at the initial operation. Of the 38 patients with residual IPMN, eight had positive IPMN margins, 23 had radiographic evidence of IPMN, and seven had both. During a mean follow-up of 73 months, 31 (20%) of 153 patients without residual IPMN developed a new radiographic lesion consistent with IPMN and, of these, three (10%) were found to represent invasive cancer. One (3%) of 38 patients with residual IPMN developed invasive cancer. In summary, in 191 initially non-invasive cases of IPMN, four invasive cancers (2%) developed during follow-up. The mean progression-free interval in these four patients was 54 months (range: 20–99 months).ConclusionsCompared with patients undergoing complete operative IPMN clearance, patients with residual IPMN after segmental pancreatectomy do not demonstrate increased risk for the development of invasive disease or reduced survival. In patients without residual IPMN who later develop new IPMN, the risk for invasive IPMN is increased.     

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.     

Dysplasia at the surgical margin is associated with recurrence after resection of non-invasive intraductal papillary mucinous neoplasms

Background

The significance of a positive margin in resected non-invasive pancreatic intraductal papillary mucinous neoplasms (IPMN) remains controversial. The aim of this study was to determine recurrence rates when dysplasia was present at the final surgical margin.

Methods

A prospectively maintained database identified 192 patients undergoing resection of non-invasive IPMN. Pathological, peri-operative and recurrence data were analysed.

Results

Ductal dysplasia was identified at the final surgical margin in 86 patients (45%) and defined as IPMN or Pancreatic Intraepithelial Neoplasia PanIN in 38 (20%) and 54 (28%) patients, respectively. At a median follow-up of 46 months, 40 (21%) patients recurred with 31 developing radiographical evidence of new cysts, 6 re-resected for IPMN and 3 diagnosed with pancreatic cancer within the remnant. Of those with margin dysplasia, 31% developed recurrent disease compared with 13% in those without dysplasia (P = 0.002). On multivariate analysis, margin dysplasia was associated with a three-fold increased risk of recurrence (P = 0.02). No relationship between dysplasia and development of pancreatic cancer was found.

Discussion

In this study, dysplasia at the margin after a pancreatectomy for non-invasive IPMN was associated with recurrence in the remnant gland, but not at the resection margin. While this finding may warrant closer follow-up, it does not identify a gland at higher risk for the subsequent development of invasive disease.     

Zystische Pankreasl?sionen

Cystic changes of the pancreas comprise a large spectrum of neoplastic and non-neoplastic lesions. Among these are five entities, i.e. pseudocysts, intraductal papillary mucinous neoplasms (IPMN), mucinous cystic neoplasms (MCN), serous cystic neoplasms (SCN) and solid pseudopapillary neoplasms (SPN), which represent 95% of all cystic pancreatic lesions. While SCN and SPN have a good prognosis, IPMN and MCN have a high risk of malignancy as they are potential precursors of pancreatic ductal adenocarcinoma. The differential diagnosis between these five entities is based on epidemiology, pathology and clinical criteria. Consideration of these criteria allows in many cases a preoperative stratification that is the basis for an adequate therapy.     

Intraductal papillary mucinous neoplasms of the pancreas: clinical surveillance and malignant progression, multifocality and implications of a field-defect

Intraductal papillary mucinous neoplasms (IPMNs) are a heterogeneous group of mucin producing cystic tumors that involve the main pancreatic duct and/or branch ducts and may be associated with invasive carcinoma. Predicting the risk of malignant transformation of an IPMN lesion can be challenging. The Sendai criteria, based in large part on radiographic imaging features, help guide surgical intervention based on the stratification of cysts into high and low risk lesions for malignancy. Invasive carcinoma may develop in the index IPMN lesion or in a separate site within the pancreas, supporting the concept of a field defect in IPMN tumorigenesis. This stresses the importance of evaluation of the entire pancreas upon diagnosis of IPMN and continued surveillance of the residual pancreas following resection. Herein, the authors summarize the data presented at the 2012 ASCO Gastrointestinal Cancers Symposium regarding prevalence and site of invasive carcinoma detected in patients undergoing surveillance for IPMN (Abstract #152).     

Pre-emptive resection for intraductal papillary mucinous neoplasia – Long-term outcome is similar between non-invasive and early invasive lesions in a tertiary single center

BackgroundPre-emptive resection for intraductal papillary mucinous neoplasm (IPMN) aims to reduce the risk before invasive transformation has taken place. Pancreatic resections are highly associated with major morbidity and mortality. Long-term overall survival (OS) after resection for invasive IPMN (inv-IPMN) in early stages is favorable. Comparison of long-term OS for resected non-invasive IPMN and early staged inv-IPMN is poorly delineated. This study aims to compare outcomes for resected non-invasive IPMN and T1-staged inv-IPMN.MethodsAll patients ≥18 years of age resected for IPMN up to stage T1 at Karolinska University Hospital between 2008 and 2020 were included. Two-year OS were compared between groups by chi-squared test, and 5-year OS was estimated using Kaplan-Meier method. Covariates associated with death was assessed in multivariable Cox regression model.ResultsWe included 284 patients, 264 (93%) non-invasive IPMN and 20 (7%) T1-staged inv-IPMN. Dysplasia of low grade (LGD) and high grade, i.e., tumor in situ (Tis) were present in 190 (67%) and 75 (26%) patients respectively. The 2-year OS for the entire cohort was 96%, and there were no differences between non-invasive and inv-IPMN (96% vs 92%, p = 0.203), nor between IPMN with LGD and Tis-T1b-staged IPMN (96% vs 95%, p = 0.734).ConclusionTwo thirds of the specimen from pre-emptive resections were of LGD and did not involve superior OS than in situ or early cancer. Due to high complication burden, efforts should be made to avoid resection when LGD is probable and rather identify more accurate predictors for surgery.     

Diagnostic dilemmas in patients with cystic neoplasms of the pancreas

Cystic neoplasms of the pancreas (CNP) are rare lesions that can be difficult to diagnose preoperatively. Twenty patients with cystic neoplasms of the pancreas including five microcystic adenomas, six benign mucinous cystic neoplasms, three malignant mucinous cystic neoplasms, two solid and papillary epithelial neoplasms, and four cystic neuroendocrine tumors were treated at a single institution between 1962 and 1987. The average duration of symptoms prior to diagnosis was 10 months. Five patients were asymptomatic. Forty percent of patients presented with an abdominal mass. Plain abdominal x-rays and UGI barium contrast studies were never diagnostic. Ultrasonography, computerized tomography (CT) and visceral angiography aided in the correct diagnosis in 28%, 36%, and 75% of patients studied, respectively. Overall a correct diagnosis was made preoperatively in only 35% of patients. Twelve of 13 patients were correctly diagnosed at laparotomy with intraoperative biopsy. Without biopsy the mass was misdiagnosed at laparotomy in five of six cases. CNP must be suspected in any patients who present with an upper abdominal mass with or without abdominal pain and no history of pancreatitis. CT may be diagnostic in up to one third of cases and should be obtained routinely to demonstrate the proximity of the lesion to other structures. Visceral angiography should also be obtained prior to operation. A generous incisional biopsy should be obtained of all pancreatic cysts that are not to be resected.     

Diagnostic dilemmas in patients with cystic neoplasms of the pancreas

Summary Cystic neoplasms of the pancreas (CNP) are rare lesions that can be difficult to diagnose preoperatively. Twenty patients with cystic neoplasms of the pancreas including five microcystic adenomas, six benign mucinous cystic neoplasms, three malignant mucinous cystic neoplasms, two solid and papillary epithelial neoplasms, and four cystic neuroendocrine tumors were treated at a single institution between 1962 and 1987. The average duration of symptoms prior to diagnosis was 10 months. Five patients were asymptomatic. Forty percent of patients presented with an abdominal mass. Plain abdominal x-rays and UGI barium contrast studies were never diagnostic. Ultrasonography, computerized tomography (CT) and visceral angiography aided in the correct diagnosis in 28%, 36%, and 75% of patients studied, respectively. Overall a correct diagnosis was made preoperatively in only 35% of patients. Twelve of 13 patients were correctly diagnosed at laparotomy with intraoperative biopsy. Without biopsy the mass was misdiagnosed at laparotomy in five of six cases. CNP must be suspected inany patients who present with an upper abdominal mass with or without abdominal pain and no history of pancreatitis. CT may be diagnostic in up to one third of cases and should be obtained routinely to demonstrate the proximity of the lesion to other structures. Visceral angiography should also be obtained prior to operation. A generous incisional biopsy should be obtained of all pancreatic cysts that are not to be resected.     

International consensus guidelines for management of intraductal papillary mucinous neoplasms and mucinous cystic neoplasms of the pancreas.

Non-inflammatory cystic lesions of the pancreas are increasingly recognized. Two distinct entities have been defined, i.e., intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm (MCN). Ovarian-type stroma has been proposed as a requisite to distinguish MCN from IPMN. Some other distinct features to characterize IPMN and MCN have been identified, but there remain ambiguities between the two diseases. In view of the increasing frequency with which these neoplasms are being diagnosed worldwide, it would be helpful for physicians managing patients with cystic neoplasms of the pancreas to have guidelines for the diagnosis and treatment of IPMN and MCN. The proposed guidelines represent a consensus of the working group of the International Association of Pancreatology.     

Clinicopathological features and medical management of intraductal papillary mucinous neoplasms

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMN) are a clinicopathological entity that is being diagnosed with increasing frequency. However, the best approach to medical management of IPMN needs to be clarified. The aim of the present study was to identify preoperative features that may be predictors of malignant IPMN, and to define the medical management of IPMN of the pancreas. METHODS: A total of 23 patients who underwent surgical resection for IPMN of the pancreas at Kochi Medical School between 1982 and 2004 were examined. Multivariate Cox regression analysis was used to identify factors independently associated with IPM carcinoma. RESULTS: Among the 23 patients, 12 had IPMN adenoma, three had borderline IPMN, four had IPMN with carcinoma in situ, and four had IPMN with invasive carcinoma. In multivariate analysis, elevated serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 levels were found to be preoperative predictors of malignant IPMN. These results suggest that the following IPMN of the pancreas should be resected: (i) IPMN of the pancreas situated in the main duct; (ii) IPMN located in the branch duct if the size of the cystic lesion is >30 mm and the mural nodules are >5 mm in height by endoscopic ultrasound (EUS); and (iii) the diameter of the main pancreatic duct is >10 mm by endoscopic retrograde pancreatography (ERP). Careful observation of patients with branch-type IPMN with small cysts and/or without mural nodules is recommended as a management strategy. CONCLUSION: The present study reinforces the need for immediate surgical resection of malignant IPMN and suggests indicators for IPMN that should assist physicians in making decisions on treatment options.     

Outcomes of nonresected main-duct intraductal papillary mucinous neoplasms of the pancreas

AIM:To compare characteristics and outcomes of resected and nonresected main-duct and mixed intraductal papillary mucinous neoplasms of the pancreas(IPMN).METHODS:Over a 14-year period,50 patients who did not undergo surgery for resectable main-duct or mixed IPMN,for reasons of precluding comorbidities,age and/or refusal,were compared with 74 patients who underwent resection to assess differences in rates of survival,recurrence/occurrence of malignancy,and prognostic factors.All study participants had dilatation of the main pancreatic duct by ≥ 5 mm,with or without dilatation of the branch ducts.Some of the nonsurgical patients showed evidence of mucus upon perendoscopic retrograde cholangiopancreatography or endoscopic ultrasound and/or after fine needle aspiration.For the surgical patients,pathologic analysis of resected specimens confirmed a diagnosis of IPMN with involvement of the main pancreatic duct or of both branch ducts as well as the main pancreatic duct.Clinical and biologic follow-ups were conducted for all patients at least annually,through hospitalization or consultation every six months during the first year of follow-up,together with abdominal imaging analysis(magnetic resonance cholangiopancreatography or computed tomography) and,if necessary,endoscopic ultrasound with or without fine needle aspiration.RESULTS:The overall five-year survival rate of patients who underwent resection was significantly greater than that for the nonsurgical patients(74% vs 58%; P =0.019).The parameters of age(< 70 years) and absence of a nodule were associated with better survival(P < 0.05); however,the parameters of main pancreatic duct diameter > 10 mm,branch ductdiameter > 30 mm,or presence of extra pancreatic cancers did not significantly influence the prognosis.In the nonsurgical patients,pancreatic malignancy occurred in 36% of cases within a mean time of 33 mo(median:29 mo; range:8-141 mo).Comparison of the nonsurgical patients who experienced disease progression with those who did not progress showed no significant differences in age,sex,symptoms,subtype of IPMN,or follow-up period; only the size of the main pancreatic duct was significantly different between these two sub-groups,with the nonsurgical patients who experienced progression showing a greater diameter at the time of diagnosis(> 10 mm).CONCLUSION:Patients unfit for surgery have a 36% greater risk of developing pancreatic malignancy of the main-duct or mixed IPMN within a median of 2.5 years.     

Clinical fate of branch duct and mixed forms of intraductal papillary mucinous neoplasia of the pancreas

Aims:  The aim of the present study was to assess the clinical fate of, and to gain new insights into, branch duct and mixed (predominantly main duct type) forms of intraductal papillary mucinous neoplasia of the pancreas (IPMN).
Methods:  During a 17-year period, 99 successive IPMN patients (52 men, 47 women; mean age, 64 years) were included and divided into two groups for further comparison: one group had branch duct IPMN, whereas the other had mixed IPMN.
Results:  Patients from the mixed IPMN group ( n  = 52) displayed a greater rate of symptoms (83% vs 55%, P  = 0.004), pancreatic resection (67% vs 38%, P  = 0.007), malignancy (35% vs 13%, P  = 0.017) and death (15% vs 4%, P  = 0.09) than those from the branch duct IPMN group. A 38-month follow up of non-operated, symptom-free patients confirmed that more than 85% of branch duct IPMN patients were asymptomatic without evidence of malignancy. Borderline lesions and carcinoma are found in up to 50% of symptomatic resected branch duct IPMN cases.
Conclusion:  Patients with the mixed form of IPMN as well as with symptomatic branch duct IPMN should require pancreatic resection because of symptoms and the risk for malignancy. In silent branch duct IPMN without radiological signs of malignancy, a non-operative watch-and-wait strategy can be discussed.     

A case of intraductal papillary mucinous neoplasm of the pancreas arising from pancreas divisum without ventral pancreatic duct of Wirsung]

Most reported cases of intraductal papillary mucinous neoplasms (IPMNs) originate from Wirsung's duct or their branches. IPMNs arising from Santorini's duct and its branches have rarely been reported. Eight cases of IPMN arising from Santorini's duct have been published worldwide. However, these cases are associated with incomplete type of pancreas divisum. Recently, one report of IPMN with complete absence of Wirsung's duct has been reported. This patient was a 57-year-old woman who was admitted to the hospital due to progressive jaundice. On endoscopic retrograde cholangiopancreatography, there was a severely bulging ampulla of Vater and patulous minor papilla draining mucinous material and a cystic lesion communicating with the dilated Santorini's duct without any communication with Wirsung's duct. A pancreaticoduodenectomy was performed and the pathologic examination of resected specimen showed no evidence of Wirsung's duct, but an IPMN arising from Santorini's duct with peripancreatic lymph node metastasis. Herein, we report a case of invasive IPMN arising from pancreatic head without ventral pancreatic duct with a review of the relevant literatures.     

Clinicopathological features of patients with concomitant intraductal papillary mucinous neoplasm of the pancreas and pancreatic endocrine neoplasm.

BACKGROUND/AIMS: The occurrence of concomitant pancreatic endocrine neoplasm (PEN) and intraductal papillary neoplasm (IPMN) of the pancreas has rarely been reported. We describe our experience with 3 patients with this association and review the existing literature. METHODS: From 1990 to 2005, 65 patients who underwent surgery for a PEN or IPMN were retrospectively reviewed. Forty-three patients had a PEN, 19 had an IPMN and 3 had both an IPMN and PEN. The 3 patients with concomitant IPMN and PEN are the focus of the current study and their clinicopathological features are reported together with 7 patients previously reported in the literature. RESULTS: There were 10 patients with a median age of 62 years (range 40-73). The male:female ratio was equal. Seven of 10 patients were symptomatic and the most common symptoms were abdominal pain (n = 5), jaundice (n = 2) and loss of weight (n = 2). The median size of the endocrine neoplasms was 14 mm (range 2-30) and they occurred in the head (n = 3), body (n = 2) and tail (n = 5). Seven of the PENs were classified as benign, 2 were potentially malignant, and 1 was frankly malignant with lymph node involvement. None of the endocrine neoplasms were functioning. The IPMNs were found in the tail (n = 4), head (n = 3), head and body (n = 1), body (n = 1) and the entire pancreas (n = 1). Five of these neoplasms were benign, 2 were borderline and 3 were malignant (1 carcinoma in situ). CONCLUSION: The occurrence of concomitant IPMN and PEN is more frequent than would be expected. However, it is difficult in the present analysis to determine if this association is more than just fortuitous.     

Analysis of clinicopathological features and predictors of malignancy in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND/AIMS: Intraductal papillary mucinous neoplasms (IPMNs) are increasingly recognized, but it is very difficult to evaluate accurately the malignancy of these neoplasms by modern imaging. We reviewed our experience in order to elucidate predictors of tumor malignancy, invasiveness, and outcome. METHODOLOGY: The clinicopathological features and surgical outcomes of 57 patients with IPMNs who underwent surgery in Nagoya University Hospital were analyzed. RESULTS: The histological diagnosis was adenoma in 40, borderline in 1, carcinoma in situ (CIS) in 7, and invasive carcinoma in 9 patients. Patients with invasive carcinomas had significantly shorter survival rates than patients with benign IPMNs or CIS (p < 0.0001). Multivariate analyses revealed that the main duct or the combined type was significantly predictive of malignancy, and both main duct or combined type and diabetes mellitus were associated significantly with invasive carcinoma. CONCLUSIONS: IPMNs generally grow slowly, but have a malignant potential that warrants radical surgical treatment when the tumor component invades the parenchyma. Our results suggest that the above factors should be considered in surgical management. The main duct type of IPMN or IPMN with mural nodules is potentially malignant or invasive. Therefore, radical operative management is indicated in these IPMNs.