Invasive cancer and survival of intraductal papillary mucinous tumors of the pancreas

Inadequacy of the eighth edition of the American Joint Committee on Cancer pancreatic cancer staging system for invasive carcinoma associated with premalignant lesions in the pancreas: an analysis using the National Cancer Database

BACKGROUND

Invasive carcinomas arising from premalignant lesions are currently staged by the same criteria as conventional pancreatic ductal adenocarcinoma.

METHODS

Clinicopathologic information and survival data were extracted through a thorough search of histology codes from National Cancer Database (2006-2016). A total of 723 patients with invasive intraductal papillary mucinous neoplasm and mucinous cystic neoplasm were analyzed.

RESULTS

The median age was 67 years, and 351 patients (48.5%) were male. There were 212 (29.3%), 232 (32.1%), 272 (37.6%), and 7 (1.0%) patients with T1, T2, T3, and T4 classification. Extrapancreatic extension (EPE) was present in 284 (39.3%). Age (HR = 1.504, 95% CI 1.196-1.891), R1 or R2 resection (HR = 1.585, 95% CI 1.175-2.140), and EPE (HR = 1.598, 95% CI 1.209-2.113) were independent prognostic factors for overall survival. Size criteria did not significantly affect survival. The median survival was 115.9 months for patients without EPE, compared to 34.2 months for those with EPE. EPE discriminated survival better than tumor size.

DISCUSSION

The T classification of the eighth edition AJCC staging system is not adequate for invasive carcinomas associated with premalignant lesions of the pancreas. They merit a separate, dedicated staging system that uses appropriate prognostic factors.

A model for predicting degree of malignancy in patients with intraductal papillary mucinous neoplasm

Background/Objectives

There is no predictive model available to address early stage malignant intraductal papillary mucinous neoplasm (IPMN) including high grade dysplasia (HGD) and pT1a (invasive component≤0.5 cm). The aim of this study was to establish an objective and sufficient model to predict the degree of malignancy in patients with IPMN, which can be easily applied in daily practice and adopted for any type of lesion.

Methods

A retrospective cohort study of 309 patients who underwent surgical resection for IPMN was performed. Members of the cohort were randomly allocated to the training or testing set. A detection tree model and random forest model were used for a 3-class classification to distinguish low grade dysplasia (LGD), HGD/pT1a IPMN, and invasive intraductal papillary mucinous cancer (I-IPMC) beyond pT1a.

Results

Of the 309 patients, 54 (17.4%) had early stage malignancy (19 HGD, 35 pT1a), 49 (15.9%) had I-IPMC beyond pT1a, and 206 (66.7%) had LGD IPMN. We proposed a 3-class classification model using a random forest algorithm, and the model had an accuracy of 99.5% with the training set, and displayed an accuracy of 96.0% with the testing set. We used SHAP for interpretation of the model and showed the top five factors (mural nodule size, main pancreatic duct diameter, CA19-9 levels, lesion edge and common bile duct dilation) were most likely to influence the 3-class classification results in terms of interpretation of the random forest model.

Conclusions

This predictive model will help assess an individual's risk for different stages of IPMN malignancy and may help identify patients with IPMN who require surgery.

A Functional Spatial Analysis Platform for Discovery of Immunological Interactions Predictive of Low-Grade to High-Grade Transition of Pancreatic Intraductal Papillary Mucinous Neoplasms

Intraductal papillary mucinous neoplasms (IPMNs), critical precursors of the devastating tumor pancreatic ductal adenocarcinoma (PDAC), are poorly understood in the pancreatic cancer community. Researchers have shown that IPMN patients with high-grade dysplasia have a greater risk of subsequent development of PDAC in the remnant pancreas than do patients with low-grade dysplasia. In this study, we built a computational prediction model that encapsulates the spatial cellular interactions in IPMNs that play key roles in the transformation of low-grade IPMN cysts to high-grade cysts en route to PDAC. Using multiplex immunofluorescent images of IPMN cysts, we adopted algorithms from spatial statistics and functional data analysis to create metrics that summarize the spatial interactions in IPMNs. We showed that an ensemble of models learned using these spatial metrics can robustly predict, with high accuracy, (1) the dysplasia grade (low vs high grade) and (2) the risk of a low-grade cyst progressing to a high-grade cyst. We obtained high classification accuracies on both tasks, with areas under the curve of 0.81 (95% confidence interval: 0.71-0.9) for task 1 and 0.81 (95% confidence interval: 0.7-0.94) for task 2. To the best of our knowledge, this is the first application of an ensemble machine learning approach for discovering critical cellular spatial interactions in IPMNs using imaging data. We envision that our work can be used as a risk assessment tool for patients diagnosed with IPMNs and facilitate greater understanding and investigation of the cellular interactions that cause transition of IPMNs to PDAC.

Natural History of Patients Followed Radiographically with Mucinous Cysts of the Pancreas

OBJECTIVE

The aim of this study was to evaluate the outcome of patients presumed to have mucinous cysts of the pancreas who were initially selected for radiographic surveillance.

METHODS

Patients with a pancreatic cyst and a measured cyst fluid carcinoembryonic antigen (CEA) ≥192 ng/mL were included. Patients were stratified by those who underwent initial resection and those who were recommended for radiographic surveillance. The natural history of these two groups was examined.

RESULTS

From 1999 to 2014, 227 patients were identified who had a cyst fluid CEA ≥192 ng/mL (median 961, range 192-300,000 ng/mL). Immediate resection was performed on 63 patients (28%). Initial radiographic surveillance was recommended for 164 patients; 87% did not have main pancreatic duct dilation, and 87% met consensus criteria for radiographic surveillance. After a median follow-up of 56 months, 48 of the 164 patients (29%) had undergone resection. Ultimately, there were three cases (2%) of high-grade dysplasia and two cases of invasive carcinoma (1%) within these 164 patients selected for observation. Three of the five cases of either high-grade dysplasia or invasive carcinoma were among the 22 patients followed outside of consensus guidelines.

CONCLUSIONS

Appropriately selected patients with mucinous pancreatic cysts can be safely followed with serial surveillance with a low risk of malignant progression.

Prognostic value of histological subtype in intraductal papillary mucinous neoplasm of the pancreas: A retrospective analysis of outcome from one single center

We sought to retrospectively analyze the outcomes of patients with intraductal papillary mucinous neoplasm (IPMN) at our pancreatic surgery center, and to evaluate the prognostic value of histological subtype.The clinical data of 121 IPMNs treated in our center between 2005 and 2014 were retrospectively analyzed. Pathological slides were thoroughly reviewed by 2 specialized pathologists.Of the 121 patients, 48, 57, and 16 had main-duct, branch-duct, and mixed type IPMNs, respectively. Forty-one patients had invasive IPMNs. Histological subtypes consisted of 35 intestinal (28.9%), 56 gastric (46.3%), 29 pancreatobiliary (24.0%), and 1 oncocytic type (0.8%). Histological subtype was associated with radiological type, T stage, and degree of dysplasia (P < .05). No significant difference in overall survival was observed among the 4 histological subtypes, regardless of whether we considered all IPMNs (P = .106), or invasive IPMNs only (P = .828). However, the overall survival was associated with radiological type, T stage, degree of dysplasia, lymph-node status, and nerve invasion. For invasive IPMNs, the overall survival was associated with nerve invasion and lymph-node status; however, the association between nerve invasion and overall survival lost statistical significance after multivariate analysis.Histological subtype had limited prognostic value in patients with IPMNs, and the main prognostic factor for patients with invasive IPMNs was the lymph-node status.

KRAS, GNAS, and RNF43 mutations in intraductal papillary mucinous neoplasm of the pancreas: a meta-analysis

Background

The prevalence and clinical significances of KRAS, GNAS, and RNF43 mutations in patients with pancreatic intraductal papillary mucinous neoplasm (IPMN) remain elusive. To evaluate the incidence of the gene mutations and clinicopathologic differences between KRAS and GNAS mutations in pancreatic cystic lesions, we performed a meta-analysis of published 33 KRAS, 11 GNAS, and 4 RNF43 studies including 1253, 835, and 143 cases, respectively.

Methods

We pooled the results of relevant studies identified using the PubMed and EMBASE databases. The effect sizes of outcome parameters were computed by the prevalence rate, weighted mean difference, or odds ratio (OR) using a random-effects model.

Results

The pooled prevalence of KRAS, GNAS, and RNF43 mutations in IPMN was 61, 56, and 23 %, respectively. The KRAS (OR 7.4 and 71.2) and GNAS (OR 30.2 and 15.3) mutations were more frequently found in IPMNs than in mucinous cystic neoplasms and in serous cystadenomas, respectively. Of the microscopic subtypes of IPMN, KRAS and GNAS were frequently mutated in gastric type (OR 2.7, P < 0.001) and intestinal type (OR 3.0, P < 0.001), respectively. KRAS mutation was infrequently found in high-grade dysplasia lesions of IPMN (OR 0.6, P = 0.032). GNAS mutation was associated with male (OR 1.9, P = 0.012).

Conclusions

This meta-analysis supports that KRAS and GNAS mutations could be diagnostic markers for IPMN. In addition, the frequencies of KRAS and GNAS mutations in IPMNs are highly variable according to the microscopic duct subtypes, reflecting their independent roles in the IPMN-adenocarcinoma sequence.

Electronic supplementary material

The online version of this article (doi:10.1186/s40064-016-2847-4) contains supplementary material, which is available to authorized users.

Expansion of epigenetic alterations in EFEMP1 promoter predicts malignant formation in pancreatobiliary intraductal papillary mucinous neoplasms

Purpose

Although limited understanding exists for the presence of specific genetic mutations and aberrantly methylated genes in pancreatobiliary intraductal papillary mucinous neoplasms (IPMNs), the fundamental understanding of the dynamics of methylation expansion across CpG dinucleotides in specific gene promoters during carcinogenesis remains unexplored. Expansion of DNA methylation in some gene promoter regions, such as EFEMP1, one of the fibulin family, with tumor progression has been reported in several malignancies. We hypothesized that DNA hypermethylation in EFEMP1 promoter would expand with the tumor grade of IPMN.

Methods

A sample of 65 IPMNs and 30 normal pancreatic tissues was analyzed. IPMNs were divided into the following three subsets according to pathological findings: 31 with low-grade dysplasia (low grade), 11 with high-grade dysplasia (high grade), and 23 with associated invasive carcinoma (invasive Ca). Mutations in the KRAS or GNAS genes were analyzed by Sanger sequencing, and methylation status of two discrete regions within the EFEMP1 promoter, namely region 1 and region 2, was analyzed by bisulfite sequencing and fluorescent high-sensitive assay for bisulfite DNA (Hi-SA). Expression status of EFEMP1 was investigated by immunohistochemistry (IHC).

Results

KRAS mutations were detected in 39, 55, and 70 % of low-grade, high-grade, and invasive Ca, respectively. GNAS mutations were observed in 32, 55, and 22 % of low-grade, high-grade, and invasive Ca, respectively. The methylation of individual regions (region 1 or 2) in the EFEMP1 promoter was observed in 84, 91, and 87 % of low-grade, high-grade, and invasive Ca, respectively. However, simultaneous methylation of both regions (extensive methylation) was exclusively detected in 35 % of invasive Ca (p = 0.001) and five of eight IPMNs (63 %) with extensive methylation, whereas 20 of 57 (35.1 %) tumors of unmethylation or partial methylation of the EFEMP1 promoter region showed weak staining EFEMP1 in extracellular matrix (p = 0.422). In addition, extensive EFEMP1 methylation was particularly present in malignant tumors without GNAS mutations and associated with disease-free survival of patients with IPMNs (p < 0.0001).

Conclusions

Extensive methylation of the EFEMP1 gene promoter can discriminate invasive from benign IPMNs with superior accuracy owing to their stepwise accumulation of tumor progression.

Electronic supplementary material

The online version of this article (doi:10.1007/s00432-016-2164-x) contains supplementary material, which is available to authorized users.

Intraductal Papillary Mucinous Neoplasm

Intraductal papillary mucinous neoplasms are cystic growths often noted incidentally in the pancreatic ducts. Left untreated, some may progress to invasive cancer.

The Neutrophil-to-Lymphocyte Ratio Predicts Malignant Potential in Intraductal Papillary Mucinous Neoplasms

BACKGROUND

Accurately identifying malignant components in patients with pancreatic intraductal papillary mucinous neoplasms (IPMN) remains challenging. Preoperative neutrophil-to-lymphocyte ratio (NLR) is a marker of poor prognosis in patients with several types of malignancy. This study assessed whether NLR was predictive of intraductal papillary mucinous carcinoma (IPMC) in patients with IPMN.

METHOD

This study retrospectively assessed 76 patients who underwent curative resection for IPMN from 1995 to 2015. The correlation between the presence of malignant components and preoperative NLR was analyzed.

RESULTS

Preoperative NLR in IPMC was significantly higher in patients with in IPMC (2.51 ± 0.84) than in patients with intraductal papillary mucinous adenoma (2.01 ± 0.71, P = 0.0079) and healthy volunteers (1.37 ± 0.33, P < 0.0001). NLR was significantly reduced after curative tumor resection. The main duct type (P = 0.0231) and NLR >2.074 (P = 0.0329) were independent predictors of IPMC in all patients. Combined criteria including international consensus guidelines, CA19-9 >37 IU/ml, and NLR >2.074 shows a high positive predictive value of 78 % and high specificity of 96 %.

CONCLUSIONS

Preoperative NLR is a useful supportive marker to predict IPMC in patients with IPMN.

Malignant transformation and overall survival of morphological subtypes of intraductal papillary mucinous neoplasms of the pancreas: A network meta-analysis

BACKGROUND

Emerging evidence suggests the predictive role of morphological subtypes (gastric, intestinal, pancreatobiliary, and oncocytic) of intraductal papillary mucinous neoplasms (IPMNs) in malignant transformation and overall survival. But results of these studies are currently discordant.

METHODS

A comprehensive literature search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) was conducted for eligible studies. Network meta-analysis using the random-effect model was carried out to detect differences in incidences of invasive IPMNs and hazard ratios from survival curves among four morphological subtypes.

RESULTS

19 studies were included in the network comparison. The outcomes showed that pancreatobiliary-type (OR for odds ratio=25.87, 95% CI: 12.11-52.10, compared with gastric-type) and oncocytic-type (OR=18.59, 95% CI: 7.18-42.74) IPMNs had the highest risks of progressing to invasive IPMNs, followed by intestinal-type (OR=5.71, 95% CI: 2.85-10.61) and gastric-type IPMNs. With the gastric type as the baseline, pancreatobiliary-type IPMNs were found to have the worst prognosis (HR for hazard ratio=5.05, 95% CrI: 1.33-13.47) while no significant differences were found for the intestinal type (HR=1.90, 95% CrI: 0.59-4.58) and the oncocytic type (HR=3.29, 95% CrI: 0.75-9.71).

CONCLUSION

It is suggested that pancreatobiliary-type IPMNs are the most likely to become invasive and are associated with poor prognosis. In contrast, the other three subtypes have similar overall survivals even though the oncocytic- and intestinal-type IPMNs are predisposed to be more invasive than gastric-type IPMNs.

Indications and outcomes of pancreatic surgery after liver transplantation

BACKGROUND

Prior liver transplantation and immunosuppression potentially translate into significant morbidity and poor outcomes after any type of pancreatic surgery. Little is known about the outcomes of pancreatic surgery after liver transplantation. This study was designed to review our experience regarding the indications and outcomes of pancreatic surgery following liver transplantation.

METHODS

A retrospective review of all liver transplant recipients who underwent pancreatic surgery between 1991 and 2009 was performed.

RESULTS

A total of 3196 patients underwent liver transplantation, of whom 18 (0.6%) subsequently required pancreatic surgery. The most common indications were necrotizing pancreatitis and lesions of the head and tail of the pancreas. Procedures performed included pancreaticoduodenectomy, distal pancreatectomy, and pancreatic necrosectomy. The estimated blood loss was 500 mL and operative time was 430 ± 224 min. Pathology results revealed malignant lesions in six (33%) patients, pre-malignant lesions in 2 (11%) patients, and benign lesions in 10 (56%) patients. The median time from transplantation to pancreatic surgery was 61 months. The 30-d postoperative complication rate was 77.8%, with median hospital stay of 15 d. The three-, 12-, and 24-month survival rates were 78%, 48%, and 24%, respectively.

CONCLUSIONS

Pancreatic surgery after liver transplantation results in significant 30-d complications. Prior liver transplantation, however, should not be a contraindication for subsequent pancreatic surgery, due to its decent survival outcome.

mAb Das-1 is specific for high-risk and malignant intraductal papillary mucinous neoplasm (IPMN)

OBJECTIVE

Intraductal papillary mucinous neoplasm (IPMN) consists of four epithelial subtypes that correlate with histological grades and risks for malignant transformation. mAb Das-1 is a monoclonal antibody against a colonic epithelial phenotype that is reactive to premalignant conditions of the upper GI tract. We sought to assess the ability of mAb Das-1 to identify IPMN with high risk of malignant transformation.

DESIGN

mAb Das-1 reactivity was evaluated in 94 patients with IPMNs by immunohistochemistry. Lesional fluid from 38 separate patients with IPMN (n=27), low-grade non-mucinous cystic neoplasms (n=7) and pseudocysts (n=4) was analysed by ELISA and western blot.

RESULTS

Immunohistochemistry-Normal pancreatic ducts were non-reactive and low-grade gastric-type IPMN (IPMN-G) (1/17) and intermediate-grade IPMN-G (1/23) were minimally reactive with mAb Das-1. In contrast, mAb Das-1 reactivity was significantly higher in high-risk/malignant lesions (p<0.0001) including: intestinal-type IPMN with intermediate-grade dysplasia (9/10); high-grade dysplasia of gastric (4/7), intestinal (12/12), oncocytic (2/2) and pancreatobiliary types (2/2); and invasive tubular (8/12), colloid (7/7) and oncocytic (2/2) carcinoma. The sensitivity and specificity of mAb Das-1 for high-risk/malignant IPMNs were 85% and 95%, respectively. Lesional fluid-Samples from low- and intermediate-grade IPMN-G (n=9), and other low-grade/benign non-mucinous lesions demonstrated little reactivity with mAb Das-1. Conversely, cyst fluid from high-risk/malignant IPMNs (n=18) expressed significantly higher reactivity (p<0.0001). The sensitivity and specificity of mAbDas-1 in detecting high-risk/malignant IPMNs were 89% and 100%, respectively.

CONCLUSIONS

mAb Das-1 reacts with high specificity to tissue and cyst fluid from high-risk/malignant IPMNs and thus may help in preoperative clinical risk stratification.

Extent of Surgery and Implications of Transection Margin Status after Resection of IPMNs

Appropriate surgical strategies for management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are a matter of debate. Preoperative and intraoperative evaluation of malignant potential of IPMN and of patient's comorbidities is of paramount importance to balance potential complications of surgery with tumors' risk of being or becoming malignant; the decision about the extent of pancreatic resection and the eventual total pancreatectomy needs to be determined on individual basis. The analysis of frozen-section margin of pancreas during operation is mandatory. The goal should be the complete resection of IPMN reaching negative margin, although there is still no agreed definition of “negative margin.” Of note, the presence of deepithelization is often wrongly interpreted as absence of neoplasia. Management of resection margin status and stratification of surveillance of the remnant pancreas, based on characteristics of primary tumour, are of crucial importance in the management of IPMNs in order to decrease the risk of tumor recurrence after resection. Although risk of local and distant recurrence for invasive IPMNs is increased even in case of total pancreatectomy, also local recurrence after complete resection of noninvasive IPMNs is not negligible. Therefore, a long-term/life-time follow-up monitoring is of paramount importance to detect eventual recurrences.

EZH2 is associated with malignant behavior in pancreatic IPMN via p27Kip1 downregulation

BACKGROUND

The epigenetic mechanism of tumorigenesis in pancreatic intraductal papillary mucinous neoplasm (IPMN) remains largely unknown. The aim of this study is to examine the role of enhancer of zeste homologue 2 (EZH2) alteration in pancreatic IPMN progression.

METHODS

Fifty-four surgically resected pancreatic IPMN specimens, including a total of 181 lesions (normal duct in 48, adenoma in 50, borderline atypia in 53, carcinoma in situ (CIS) in 19, and invasive carcinoma in 11) were analyzed by immunohistochemical staining (EZH2, Ki-67, p27Kip1). Using paraffin embedded sections, total RNA was successfully extracted from 20 IPMN lesions (borderline IPMN in 9, CIS in 6, invasive carcinoma in 5) and 7 pancreatic normal ducts, and then levels of EZH2 and p27Kip1 mRNA were analyzed by real time PCR.

RESULTS

In immunohistochemical analysis, cell proliferative activity revealed by Ki-67 positive nuclei was increased during IPMN progression (normal duct<adenoma<borderline atypia<CIS ≈ invasive carcinoma). EZH2 expression displayed a similar pattern (normal duct<adenoma<borderline atypia<CIS ≈ invasive carcinoma) with cell proliferative activity. EZH2 expression in malignant (CIS and invasive carcinoma) IPMNs was significantly higher than that in adenoma and borderline-atypia IPMNs. EZH2 expression level in IPMN lesions was positively correlated with the Ki-67 positive nuclear ratio (p<0.0001). EZH2-positive cells in malignant IPMN did not express p27Kip1. EZH2 mRNA expressions in malignant lesions were significantly higher than those in benign lesions (p<0.0001). In contrast, p27Kip1 mRNA in malignant lesions was significantly decreased compared to those in benign lesion (p<0.05), and there was an inverse correlation between EZH2 and p27Kip1 mRNA levels (p = 0.0109).

CONCLUSION

EZH2 is associated with the accelerated cell proliferation and malignant step in pancreatic IPMN via the downregulation of p27Kip1.

Intravoxel incoherent motion diffusion-weighted MR imaging for characterization of focal pancreatic lesions

PURPOSE

To evaluate the diagnostic potential of apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM)-derived parameters for differentiation of common pancreatic tumors, chronic pancreatitis, and normal pancreas and for characterization of the malignancy potential of intraductal papillary mucinous neoplasms (IPMNs).

MATERIALS AND METHODS

The institutional review board approved this retrospective study, and informed consent was waived. Ninety-three consecutive patients with surgically resected and pathologically confirmed pancreatic tumors (39 pancreatic adenocarcinomas [PACs], 17 neuroendocrine tumors [NETs], and 37 IPMNs), seven patients with chronic pancreatitis, and 26 patients with a normal pancreas were included in this study. All patients underwent pancreatic 3.0-T magnetic resonance imaging, including IVIM diffusion-weighted imaging with 10 b values used (from 0 to 1000 sec/mm(2)). The ADC, slow component of diffusion (D(slow)), incoherent microcirculation (D(fast)), and perfusion fraction (f) were calculated. Steel-Dwass and Mann-Whitney U tests were used for comparison. The diagnostic performance of the parameters was evaluated by using receiver operating characteristic (ROC) analysis with Bonferroni correction.

RESULTS

Among ADC- and IVIM-derived parameters, D(fast) and f values of PACs were significantly lower than those of normal pancreas, chronic pancreatitis, and NETs (all P < .05 in post hoc analyses). For differentiation of PACs from NETs, f and D(fast) showed a significant difference (P < .0001 for both) and were more useful parameters than ADC and D(slow) in ROC analysis (all P < .05). Malignant IPMNs had significantly lower ADC and D(slow) values and higher D(fast) and f values when compared with benign IPMNs (all P < .05). In ROC analysis, f showed the highest area under the ROC curve value for distinguishing malignant from benign IPMNs.

CONCLUSION

IVIM-derived perfusion-related parameters could be helpful for the differentiation of common malignant tumors in the pancreas and for distinguishing malignant from benign IPMNs. D(fast) and f were more valuable parameters in the differentiation of PACs from NETs than were ADC and D(slow).

aPKCλ/ι is a beneficial prognostic marker for pancreatic neoplasms

Pancreatic cancer is a lethal disease. Overall survival is typically 6 months from diagnosis. Determination of prognostic factors in pancreatic cancer that would allow identification of patients who could potentially benefit from aggressive treatment is important. However, until date, there are no established reliable prognostic factors for pancreatic cancer patients. Herein, we propose a beneficial biomarker which is significantly correlated with the prognosis in pancreatic cancer patients. Atypical protein kinase C λ/ι (aPKCλ/ι) is overexpressed and has been implicated in the progression of several cancers. We tested the expression levels of aPKCλ/ι in two types of pancreatic neoplasm, pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasms (IPMNs), by immunohistochemistry. Examination of the aPKCλ/ι expression levels in surgically resected specimens of PDCA (n = 115) demonstrated that the expression levels of aPKCλ/ιin PDAC had prognostic implications, independent of the Tumor-Node-Metastasis classification and World Health Organization tumor grade. In the case of IPMNs (n = 46) also, the expression levels of aPKCλ/ιin IPMN were found to be of prognostic importance, independent of the World Health Organization histological grade or morphological type. Interestingly, high expression levels of aPKCλ/ι were significantly correlated with a worse histological grade (p = 0.010) and advanced stage of the tumor (p = 0.0050) in IPMN patients. These findings suggest that high expression levels of aPKCλ/ι could be involved in the malignant transformation of IPMNs. Based on these observations, we propose the expression level of aPKCλ/ι as a prognostic marker common to different types of pancreatic neoplasms.

Glycemic control after total pancreatectomy for intraductal papillary mucinous neoplasm: an exploratory study

Background. Glycemic control following total pancreatectomy (TP) has been thought to be difficult to manage. Diffuse intraductal papillary mucinous neoplasm (IPMN) is a potentially curable precursor to pancreatic adenocarcinoma, best treated by TP. Objective. Compare glycemic control in patients undergoing TP for IPMN to patients with type 1 diabetes mellitus (DM). Design/Setting. Retrospective cohort. Outcome Measure. Hemoglobin A1C(HbA1C) at 6, 12, 18, and 24 months after TP. In the control group, baseline was defined as 6 months prior to the first HbA1c measure. Results. Mean HgbA1C at each point of interest was similar between TP and type I DM patients (6 months (7.5% versus 7.7%, P = 0.52), 12 months (7.3% versus 8.0%, P = 0.081), 18 months (7.7% and 7.6%, P = 0.64), and at 24 months (7.3% versus 7.8%, P = 0.10)). Seven TP patients (50%) experienced a hypoglycemic event compared to 65 type 1 DM patients (65%, P = 0.38). Limitations. Small number of TP patients, retrospective design, lack of long-termfollowup. Conclusion. This suggests that glycemic control following TP for IPMNcan be well managed, similar to type 1 DM patients. Fear of DM following TP for IPMN should not preclude surgery when TP is indicated.

Stromal galectin-1 expression is associated with long-term survival in resectable pancreatic ductal adenocarcinoma

The overall 5 year survival rate for pancreatic ductal adenocarcinoma (i.e., PDAC) is a dismal 5%, although patients that have undergone surgical resection have a somewhat better survival rate of up to 20%. Very long-term survivors of PDAC (defined as patients with ≥ 10 year survival following apparently curative resection), on the other hand, are considerably less frequent. The molecular characteristics of very long-term survivors (VLTS) are poorly understood, but might provide novel insights into prognostication for this disease. In this study, a panel of five VLTS and stage-matched short-term survivors (STS, defined as disease-specific mortality within 14 months of resection) were identified, and quantitative proteomics was applied to comparatively profile tumor tissues from both cohorts. Differentially expressed proteins were identified in cancers from VLTS vs. STS patients. Specifically, the expression of galectin-1 was 2-fold lower in VLTS compared with STS tumors. Validation studies were performed by immunohistochemistry (IHC) in two additional cohorts of resected PDAC, including: 1) an independent cohort of VLTS and 2) a panel of sporadic PDAC with a considerable range of overall survival following surgery. Immunolabeling analysis confirmed that significantly lower expression of stromal galectin-1 was associated with VLTS (p = 0.02) and also correlated with longer survival in sporadic, surgically-treated PDAC cases (hazard ratio = 4.9, p = 0.002). The results from this study provide new insights to better understand the role of galectin-1 in PDAC survival, and might be useful for rendering prognostic information, and developing more effective therapeutic strategies aimed at improving survival.

The distribution of atypical epithelium in main-duct type intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND/PURPOSE

The purpose of this study was to obtain the fundamental data necessary to discuss the appropriate operative mode for the resection of main-duct type intraductal papillary mucinous neoplasms (mIPMNs) of the pancreas.

METHODS

In 23 patients who underwent total pancreatectomy with preoperative and postoperative diagnoses of mIPMN, the imaging studies and clinicopathological data were collected. The whole pancreatic specimen was histologically evaluated, and the distribution of atypical epithelium was mapped on a schema.

RESULTS

Pathological examination of the specimens revealed that 18 patients had carcinoma in the pancreas; 8 patients had invasive lesions and one patient had lymph node metastasis. Specimens from 5 patients did not bear carcinoma lesions but had widespread borderline lesions in the pancreas. The mapping of lesions in the pancreatic specimens revealed that, at least, borderline or higher lesions were present both in the head and distal pancreas in all patients. In the majority of the specimens, lesions from adenoma to carcinoma co-existed on the same slide, and there were normal cell intervals between the malignant lesions.

CONCLUSION

We conclude that total pancreatectomy should be performed for mIPMN when dilatation of the main duct suggests possible spread of the lesion to the whole pancreas.

Volumetric and morphological analysis of intraductal papillary mucinous neoplasm of the pancreas using computed tomography and magnetic resonance imaging

OBJECTIVE

The purpose of this study was to predict the malignancy of intraductal papillary mucinous neoplasm (IPMN) based on data obtained by computed tomography and magnetic resonance imaging.

METHODS

Sixty-nine patients with IPMN underwent computed tomography, magnetic resonance imaging, and surgery. The tumors were classified pathologically as IPMN (adenoma), IPMN (in situ carcinoma), and invasive carcinoma derived from IPMN, and analyzed morphologically for the following characteristics: tumor size, main pancreatic duct (MPD) diameter, tumor area, MPD area, tumor volume, MPD volume, and intraductal volume (tumors volume + MPD volume).

RESULTS

Main pancreatic duct diameter (P = 0.017) and intraductal volume (P = 0.0013) showed significant differences among IPMN (adenoma), IPMN (in situ carcinoma), and invasive carcinoma derived from IPMN. When IPMN (in situ carcinoma) and invasive carcinoma derived from IPMN were classified as malignant IPMN, an MPD diameter of 6 mm or more and an intraductal volume of 10 cm or more were set as cutoff levels predictive of malignancy using receiver operating characteristic curve analysis. On the basis of these criteria, the sensitivity and specificity for identifying malignancy in MPD were 83% and 59%, and those for intraductal volume were 70% and 73%, respectively.

CONCLUSION

Intraductal volume (≥10 cm) determined by volumetric analysis is useful for diagnosis of malignant IPMN.

Molecular characteristics and biological behaviours of the oncocytic and pancreatobiliary subtypes of intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasm (IPMN) consists of four epithelial subtypes. Of those, pancreatobiliary and oncocytic types are recently recognized and relatively uncommon, and usually exhibit high-grade dysplasia. The biological properties and molecular characteristics of these two types have not been well documented. The few molecular studies of the oncocytic type showed absence of KRAS mutations commonly seen in the other subtypes, raising the possibility that the oncocytic type is distinct from the other subtypes. Thus, we examined clinicopathological features and molecular alterations of the two subtypes. The study cohort consisted of 12 pancreatobiliary and 18 oncocytic IPMN cases. KRAS, BRAF, and PIK3CA mutations and TP53, SMAD4, and β-catenin expression were analysed, and the results of molecular and clinicopathological profiles were compared between the two subtypes. KRAS mutations were identified in the oncocytic type, but less frequently than the pancreatobiliary type (17% versus 58%, p = 0.048). BRAF mutation was found in a single oncocytic tumour, and no PIK3CA mutations were seen in any of the study cohort. TP53 overexpression was less frequent in the oncocytic type than in the pancreatobiliary type (11% versus 58%, p = 0.013). Invasive components were present in 50% of the oncocytic and 92% of the pancreatobiliary types, with lymph node metastasis more frequently seen in the latter, corresponding to better outcomes in the former (5-year survival rates: 93% versus 32%, p = 0.014). Our demonstration of KRAS and BRAF mutations in the oncocytic-type IPMN supports a role for the activation of the RAS-MAPK pathway in this tumour type. However, the less frequent TP53 overexpression associated with the significantly lower rates of invasion and nodal disease in the oncocytic type correlates with better outcomes compared to the pancreatobiliary type.

Risk factors associated with the postoperative recurrence of intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVES

The risk factors correlated with the post-operative recurrence of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are not well established. The aim was to determine the risk factors of recurrence.

METHODS

We reviewed retrospectively the differences of clinicopathologic features between the recurrence and nonrecurrence groups of patients with IPMN who underwent surgical resection and analyzed the recurrence-related factors.

RESULTS

A total of 103 patients were confirmed to have IPMNs. The mean postoperative follow-up was 3.2 years, and the recurrence rate was 12.6%. Recurrent cases (n=13) had the following pathologic grades: adenoma, 1; and invasive carcinoma, 12. The mean postoperative survival was 17.0 months in the recurrence group and 41.4 months in the nonrecurrence group (P<0.001). The independent risk factors of recurrence were invasive carcinoma (P=0.017, hazard ratio=71.79; 95% confidence interval (CI)=2.13-2417.05), elevated carbohydrate antigen 19-9 (P=0.007, hazard ratio=37.97, 95% CI=2.66-542.32), and main location in the pancreatic head (P=0.038, hazard ratio=0.16, 95% CI=0.03-0.90).

CONCLUSIONS

The risk factors associated with recurrence of IPMNs were invasive pathology, elevated carbohydrate antigen 19-9, and main location in the pancreatic head. A more careful follow-up is needed for such patients.

Predictive factors associated with malignancy of intraductal papillary mucinous pancreatic neoplasms

AIM: To identify preoperative predictive factors associated with malignancy of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.

METHODS: Between April 1995 and April 2010, 129 patients underwent surgical resection for IPMNs at our institute and had confirmed pathologic diagnoses. The medical records were retrospectively reviewed and immunohistochemical staining for mucin (MUC) in pancreatic tissues was performed.

RESULTS: Univariate analysis showed that the following five variables were closely associated with malignant IPMNs preoperatively: absence of extrapancreatic malignancy; symptoms; tumor size > 4 cm; main pancreatic duct (MPD) size > 7 mm; and lymph node enlargement on preoperative computed tomography (CT). Multivariate analysis revealed that the following two factors were significantly associated with malignant IPMNs preoperatively: MPD size > 7 mm [odds ratio (OR) = 2.50]; and lymph node enlargement on preoperative CT (OR = 3.57). No significant differences in the expression of MUC1, MUC2 and MUC5AC were observed between benign and malignant IPMNs.

CONCLUSION: MPD size > 7 mm and preoperative lymph node enlargement on CT are useful predictive factors associated with malignancy of IPMNs.

Prediction of invasive carcinoma in branch type intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

Patients with branch duct type intraductal papillary mucinous neoplasm (BD-IPMN) without invasion usually show favorable prognosis. However, the prognosis becomes poor when the IPMN lesions give rise to invasive carcinoma cells. In addition, recent studies have revealed that BD-IPMN is frequently complicated by common type pancreatic ductal carcinoma. Thus, the prognosis of BD-IPMN depends on the occurrence of these two types of invasive carcinoma. However, little is known about the risk factors for the development of these invasive carcinomas in BD-IPMN. This study aims to identify the factors which predict the development of invasive carcinoma in BD-IPMN.

METHODS

Invasive pancreatic carcinoma associating with BD-IPMN was classified as invasive IPMN group (invasive carcinoma derived directly from IPMN lesions) and concomitant group (common type of invasive carcinoma concomitant with BD-IPMN). The relation between the incidence of each type of invasive carcinoma in BD-IPMN and the clinicopathological parameters was retrospectively analyzed.

RESULTS

There were 12 patients with invasive IPMN and 7 patients with concomitant cancer in 159 patients with BD-IPMN. Diameter of dilated branch (P < 0.001) or main pancreatic duct (MPD) (P = 0.001), size of mural nodule (P < 0.001), serum CEA level (P < 0.001) and serum CA19-9 level (P < 0.001) were factors associated significantly with invasive IPMN by univariate analysis. Among these factors, mural nodule with size larger than 6.5 mm [odds ratio 14.86 (95% CI 1.37-60.45); P = 0.02] and serum carcinoembryonic antigen (CEA) level over 5 ng/ml [odds ratio 6.91 (95% CI 1.17-54.13); P = 0.03] were found to be the factors independently associated with invasive IPMN. On the other hand, both univariate and multivariate analyses revealed that elevated carbohydrate antigen 19-9 (CA 19-9) levels were associated with the occurrence of concomitant ductal carcinoma in BD-IPMN [odds ratio 10.31 (95% CI 1.77-81.51); P = 0.01].

CONCLUSIONS

Our results suggested that careful imaging study of the entire pancreas in addition to tumor lesions and measurement of serum CEA and CA19-9 would be required to find out the development of the two types of invasive carcinoma in BD-IPMN.

Intraductal papillary mucinous neoplasms of the pancreas: diagnosis and management

Intraductal papillary mucinous neoplasms (IPMNs), characterized by intraductal papillary growth and thick mucin secretion, have increasingly been recognized. Despite modern preoperative evaluation, major difficulties still remain in distinguishing malignant invasive types from benign IPMNs. Following a PubMed database search, all relevant abstracts and articles on IPMN published in English and Chinese were reviewed. Main-duct and the mixed type IPMNs carry a higher risk of malignancy as compared with branch-duct type IPMNs. Treatment of branch-duct type IPMNs remains controversial. Once operation is indicated, intraoperative frozen section of margins plays an important role in the decision concerning the extent and type of surgery. Pancreatectomy, partly preserving both endocrine and exocrine pancreatic function, is advocated for most patients with IPMN, though total pancreatectomy may be necessary in some. Both for patients subjected to surgery and those only observed, IPMN patients need regular close follow-up to identify recurrence or progressive disease.

Validating a simple scoring system to predict malignancy and invasiveness of intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

The objective of the present study was to identify reliable preoperative factors predicting malignancy or invasiveness of intraductal papillary mucinous neoplasm (IPMN) of the pancreas and the effectiveness of a diagnostic scoring system based on these factors.

METHODS

Between August 1994 and December 2007, 204 patients underwent pancreatic resection for IPMN at a single institute. Medical records were reviewed retrospectively, and a new diagnostic scoring system for predicting malignant IPMN preoperatively was designed.

RESULTS

Univariate analysis revealed nine significant predictors of both malignant and invasive IPMN: age > or =60 years, history of pancreatitis, presence of mural nodule(s), diameter of main pancreatic duct (MPD) >6 mm, main duct or mixed type, total bilirubin >1.2 mg/dl, CA-19-9 >37 U/ml, tumor location in the pancreatic head, and tumor size >30 mm. Multivariate analysis showed that age, pancreatitis, mural nodule(s), and MPD diameter were independent predictors of invasive IPMN, and that all these parameters, plus elevated carbohydrate antigen-19-9 (CA-19-9), were independent predictors of malignant IPMN. A scoring system based on these five factors, each assigned 1 point, and with a cut-off of 3 points, could predict malignant IPMN with a sensitivity of 50.7% and a specificity of 90.1%. The 5-year survival rates of patients with benign and malignant IPMN were 95.0% and 64.0%, respectively.

CONCLUSIONS

Our scoring system using five independent factors (age > or =60 years, history of pancreatitis, presence of mural nodule(s), elevated level of CA-19-9, and MPD diameter >6 mm) may be helpful for predicting malignancy and postoperative survival.

Metachronous intraductal papillary mucinous neoplasm with carcinoma in situ of the pancreas arising within a short interval: report of a case

A 61-year-old man with an intraductal papillary mucinous neoplasm (IPMN) and carcinoma in situ (CIS) of the pancreatic body initially underwent a distal pancreatectomy. Postoperative follow-up included computed tomography (CT) and ultrasonography (US) every 6 months. Intraductal papillary mucinous neoplasm of the pancreatic head was diagnosed 17 months later using peroral pancreatoscopy (POPS) including a biopsy, revealing IPMN with highly dysplastic changes. A total pancreatectomy was therefore performed. The pathological examination revealed IPMN with CIS. The patient was discharged from the hospital and is doing well as of 1 year postoperatively. Although cautious surveillance seems mandatory, consensus has not yet been reached regarding postoperative surveillance. This report presents an unreported case of metachronously arising IPMN with CIS within a relatively early interval, thus suggesting that surveillance every 6 months is preferable to > or = 1 year. In addition, endoscopic US, endoscopic retrograde cholangiopancreatography, intraductal US, or POPS should be included in pathological examinations to avoid missing opportunities to treat lesions such as noninvasive IPMN with a good prognosis. Surgically indicated patients with noninvasive recurrence should therefore be strongly considered to undergo a total pancreatectomy.

Intraductal papillary mucinous neoplasm: a clinicopathologic review

Intraductal papillary mucinous neoplasm (IPMN) is an intraductal mucin-producing epithelial neoplasm that arises from the main pancreatic duct (MD-IPMN), secondary branch ducts (BD-IPMN), or both (mixed type; Mix-IPMN). Neoplastic progression from benign adenoma to invasive adenocarcinoma has not been proven but is generally thought to occur. With increasing recognition of IPMN, our understanding of the diagnosis and management of the tumors is evolving. At present, treatment options for patients with IPMN range from observation to pancreatic resection depending on the natural history of the lesion. This review focuses on currently available data that guide management decisions for patients with IPMN.

Asymptomatic pancreatic cystic neoplasms: maximizing survival and quality of life using Markov-based clinical nomograms

BACKGROUND & AIMS

The natural history and management of pancreatic cysts, especially for branch duct intraductal papillary mucinous neoplasms (BD-IPMNs), remain uncertain. We developed evidence-based nomograms to assist with clinical decision making.

METHODS

We used decision analysis with Markov modeling to compare competing management strategies in a patient with a pancreatic head cyst radiographically suggestive of BD-IPMN, including the following: (1) initial pancreaticoduodenectomy (PD), (2) yearly noninvasive radiographic surveillance, (3) yearly invasive surveillance with endoscopic ultrasound, and (4) "do nothing." We derived probability estimates from a systematic literature review. The primary outcomes were overall and quality-adjusted survival. We depicted the results in a series of nomograms accounting for age, comorbidities, and cyst size.

RESULTS

Initial PD was the dominant strategy to maximize overall survival for any cyst greater than 2 cm, regardless of age or comorbidities. In contrast, surveillance was the dominant strategy for any lesion less than 1 cm. However, when measuring quality-adjusted survival, the do-nothing approach maximized quality of life for all cysts less than 3 cm in patients younger than age 75. Once age exceeded 85 years, noninvasive surveillance dominated. Initial PD did not maximize quality of life in any age group or cyst size.

CONCLUSIONS

Management of pancreatic cysts can be guided using novel Markov-based clinical nomograms, and depends on age, cyst size, comorbidities, and whether patients value overall survival vs quality-adjusted survival. For patients focused on overall survival, regardless of quality of life, surgery is optimal for lesions greater than 2 cm. For patients focused on quality-adjusted survival, a 3-cm threshold is more appropriate for surgery except for the extreme elderly.

Imaging features of intraductal papillary mucinous neoplasms of the pancreas in multi-detector row computed tomography

AIM: To retrospectively evaluate the imaging features of pancreatic intraductal papillary mucinous neoplasms (IPMNs) in multi-detector row computed tomography (MDCT).

METHODS: A total of 20 patients with pathologically-confirmed intraductal papillary mucinous neoplasms (IPMNs) were included in this study. Axial MDCT images combined with CT angiography (CTA) and multiplanar volume reformations (MPVR) or curved reformations (CR) were preoperatively acquired. Two radiologists (Tan L and Wang DB) reviewed all the images in consensus using an interactive picture archiving and communication system. The disputes in readings were resolved through consultation with a third experienced radiologist (Chen KM). Finally, the findings and diagnoses were compared with the pathologic results.

RESULTS: The pathological study revealed 12 malignant IPMNs and eight benign IPMNs. The diameters of the cystic lesions and main pancreatic ducts (MPDs) were significantly larger in malignant IPMNs compared with those of the benign IPMNs (P < 0.05). The combined-type IPMNs had a higher rate of malignancy than the other two types of IPMNs (P < 0.05). Tumors with mural nodules and thick septa had a significantly higher incidence of malignancy than tumors without these features (P < 0.05). Communication of side-branch IPMNs with the MPD was present in nine cases at pathologic examination. Seven of them were identified from CTA and MPVR or CR images. From comparison with the pathological diagnosis, the sensitivity, specificity, and accuracy of MDCT in characterizing the malignancy of IPMN of the pancreas were determined to be 100%, 87.5% and 95%, respectively.

CONCLUSION: MDCT with CTA and MPVR or CR techniques can elucidate the imaging features of IPMNs and help predict the malignancy of these tumors.

Main pancreatic duct intraductal papillary mucinous neoplasms: accuracy of MR imaging in differentiation between benign and malignant tumors compared with histopathologic analysis

PURPOSE

To retrospectively determine the accuracy of magnetic resonance (MR) imaging combined with MR cholangiopancreatography (CP) in differentiating benign from malignant intraductal papillary mucinous neoplasms (IPMNs) involving the main pancreatic duct (MPD), with histopathologic analysis as the reference standard.

MATERIALS AND METHODS

The informed consent requirement was waived for this institutional review board-approved study. A total of 51 patients with histopathologically proved IPMNs (MPD IPMN, n = 29; mixed type IPMN, n = 22), underwent MR imaging, MR CP, and surgery, with a mean interval of 2.6 months between MR examination and surgery. Qualitative image analysis included assessment of the site of MPD dilatation (head of the pancreas, body and/or tail of the pancreas, or diffuse), presence or absence of duct wall nodules, and contrast enhancement of the MPD walls. Quantitative image analysis included measurement of the maximum diameter of the MPD. A comparison of adenomas and borderline IPMNs with cancerous IPMNs was performed with the Student t test or the Mann-Whitney U test for continuous variables.

RESULTS

At histopathologic analysis, 27 IPMNs were classified as carcinomas; 13, as borderline tumors; and 11, as adenomas. MPD wall nodules were observed in 16 carcinomas involving the MPD and one adenoma or borderline neoplasm (P < .00001). Duct wall enhancement was observed in 20 MPD or mixed type carcinomas and five adenomas or borderline neoplasms (P = .0001). The median maximal diameter of the MPD was 18 mm in malignant MPD or mixed type IPMNs and 11 mm in benign borderline IPMNs (P = .038). No significant difference in the overall 5-year survival rate of patients with MPD IPMNs and those with mixed type IPMNs was observed (P = .813).

CONCLUSION

Duct wall nodules and enhancement of the MPD walls are signs of malignant MPD or mixed type IPMNs.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.2531080604/-/DC1.

Preoperative evaluation of invasive and noninvasive intraductal papillary-mucinous neoplasms of the pancreas: clinical, radiological, and pathological analysis of 123 cases

OBJECTIVE

We aimed to investigate preoperative findings that are useful to distinguish intraductal papillary-mucinous neoplasm (IPMN) subtypes.

METHODS

One hundred twenty-three patients who underwent pancreatectomy for IPMN were analyzed clinicopathologically and radiologically. Invasive IPM carcinomas (IPMCs) were subdivided into early-stage nonaggressive (minimally invasive IPMC [MI-IPMC]) and more advanced and aggressive (invasive carcinoma originating in IPMC [IC-IPMC]) subtypes according to our recently proposed pathological criteria.

RESULTS

The lesions consisted of 27 IPMNs with low-grade dysplasia, 14 IPMNs with moderate dysplasia, 21 IPMNs with high-grade dysplasia, 30 MI-IPMCs, and 31 IC-IPMCs. Multidetector-row computed tomography detected a component of invasive carcinoma in IC-IPMC with 86% sensitivity and 100% specificity. In patients with IPMNs other than IC-IPMC, multivariate analysis demonstrated 3 significant predictive factors of malignancy: IPMN size (>40 mm), IPMN duct type (main pancreatic duct or mixed type), and the presence of a mural nodule or thick septum. The diagnostic score obtained using these 3 factors showed a strong correlation with the presence of malignancy.

CONCLUSIONS

For preoperative evaluation of patients with IPMN, it is recommended to rule out IC-IPMC using multidetector-row computed tomography and then to categorize IPMN other than IC-IPMC according to malignant potential based on the diagnostic score.

Long-term survival (5-20 years) after pancreatectomy for pancreatic ductal adenocarcinoma: a series of 30 patients collected from 3 institutions

OBJECTIVES

Long-term survival after pancreatectomy for pancreatic duct adenocarcinoma has been rarely reported. Factors influencing survival are still debated. The aim of the study is to report a French multicentric series of long-term survivors after pancreatectomy for pancreatic duct adenocarcinoma.

METHODS

Data of patients who survived >5 years (February 1983-January 2000) were analyzed. All operative specimens were reviewed. Patients with intraductal-papillary-mucinous-neoplasia, cystadenocarcinoma, acinous-adenocarcinoma, neuroendocrine, or mixed tumors were excluded.

RESULTS

Long-term survivors were 20 men and 10 women, with median age of 61 years. Twenty-five patients had pancreaticoduodenectomies (6 pylorus preserving pancreatoduodenectomy [PPPD]), 3 had total pancreaticoduodenectomies, and 2 had splenopancreatectomies. Three patients had portal vein resection, 1 had hepatic artery resection-reconstruction, and 1 had segmentectomy for liver metastasis. All resections were complete macroscopic and microscopic resection (R0). Median tumor size was 30 mm. Tumors were pT2 (n = 1), pT3 (n = 24), pT4 (n = 5), 12 N+, 1 M+. Twenty patients had adjuvant radiotherapy, and 18 had concomitant chemotherapy. Median survival was 7.3 years (range, 5.2-21 years). Nineteen patients are alive, 1 with recurrence and 18 with no evidence of disease (2 had more than 20 years of follow-up). Eleven patients died, 6 from recurrence.

CONCLUSIONS

Pancreatic duct adenocarcinoma can be cured, and long-term survival after R0 curative surgery has become a reality. Long-term survivors did not fulfil the ideal prognostic criteria and even presented with advanced stage.

Synchronous and metachronous extrapancreatic malignant neoplasms in patients with intraductal papillary-mucinous neoplasm of the pancreas

BACKGROUND/AIMS

Patients with intraductal papillary-mucinous neoplasm (IPMN) of the pancreas are likely to have a better prognosis than those with conventional pancreatic ductal adenocarcinoma. Recently there have been some reports on extrapancreatic malignant neoplasms (EPM) occurring in patients with IPMN. The purpose of this study was to discover the characteristic features of IPMN with EPM compared with IPMN without EPM.

METHODS

61 patients with IPMN who underwent surgery at Tohoku University Hospital between 1988 and 2006 were retrospectively analyzed.

RESULTS

The 61 patients with IPMN in this study comprised 25 with intraductal papillary-mucinous adenomas (IPMA) and 36 with intraductal papillary-mucinous carcinomas (IPMC) including 6 with invasive carcinomas. Synchronous and metachronous EPM were observed in 15 out of the 61 patients (24.6%). Three of these patients, including 2 with IPMA and 1 with invasive carcinoma associated with IPMC, died of the EPM. None of the features, including sex, age, smoking, family history, macroscopic types (main duct type or branch duct type), histological types (gastric, intestinal, pancreatobiliary or oncocytic), and aberrant expression of molecules including CDKN2A, TP53, SMAD4 and DUSP6, except for the histological diagnoses were associated with the occurrence of EPM, i.e., the EPM occurred more often in patients with IPMA (10 out of 25) than in those with IPMC (5 out of 36) in our series (p = 0.0199 by the chi(2) test, p = 0.0330 by Fisher's exact probability test, p = 0.0422 by Yates' correction).

CONCLUSION

Patients with IPMA were more likely to have EPM than those with IPMC. Patients with IPMA are usually expected to have a fair prognosis but EPM could be fatal in some of them, so it must be noted during follow-up.

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 > or = 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.

Minimally invasive intraductal papillary-mucinous carcinoma of the pancreas: clinicopathologic study of 104 intraductal papillary-mucinous neoplasms

Invasive intraductal papillary-mucinous carcinoma (I-IPMC) is a heterogeneous entity with various postoperative outcomes. The aim of this study is to characterize early-stage I-IPMC with nonaggressive characteristics. One hundred and four patients with intraductal papillary-mucinous neoplasm (IPMN) were clinicopathologically investigated. The lesions were classified into 53 noninvasive IPMNs (adenoma, borderline, and noninvasive IPMC) and 51 I-IPMCs on the basis of the WHO classification. I-IPMCs were divided further into 26 minimally invasive IPMCs (MI-IPMCs) and 25 invasive carcinomas originating in IPMC (IC-IPMCs) by new diagnostic criteria proposed in this study. We examined invasiveness of I-IPMC on 4 patterns, and defined simple and practical diagnostic criteria of minimal invasion for each invasive pattern. The disease-specific survival rates after 3, 5, and 10 years were 100%, 100%, and 100% for both noninvasive IPMN and MI-IPMC, and 51%, 38%, and 0% for IC-IPMC. The overall and disease-specific survival rates for MI-IPMC were both significantly better than those for IC-IPMC (P<0.001), but there was no significant difference between noninvasive IPMN and MI-IPMC. Multivariate analysis showed that the factors indicative of poor prognosis were a diagnosis of I-IPMC classified as IC-IPMC and a high level of serum carbohydrate antigen 19-9. The prognosis of IC-IPMC was not significantly different from that of pancreatic ductal carcinoma in each of the corresponding tumor-node-metastasis stages. These findings suggest that a category of MI-IPMC provides more accurate and useful information of the stage and the aggressiveness of I-IPMC.

Intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are now a well-recognized category of slowly growing tumors with a remarkably better prognosis, even when malignant, than pancreatic ductal adenocarcinoma. Their clinical and pathohistologic features have been increasingly attracting the attention of clinicians since their first description 25 years ago. Despite its burgeoning volume recently, accumulated literature devoted to IPMN still provides a low level of evidence with regard to diagnosis, treatment, and prognosis. Therefore, we performed a Medline-based systematic review of the literature aimed at clearly defining the clinicopathologic characteristics of pancreatic IPMN and determining the best currently available evidence-based principles of diagnosis and management of patients with this disease.

Mutational analyses of multiple oncogenic pathways in intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVE

There is much accumulated evidence that EGFR, HER2, and their downstream signaling pathway members such as KRAS, BRAF, and PIK3CA are strongly implicated in cancer development and progression. Recently, mutations in the kinase domains of EGFR and HER2, associated with increased sensitivity to tyrosine kinase inhibitors, have been described.

METHODS

To evaluate the mutational status of these genes in intraductal papillary mucinous neoplasm (IPMN)/intraductal papillary mucinous carcinoma (IPMC), EGFR and HER2 were analyzed in 36 IPMN/IPMC, and the results were correlated to the mutational status of the KRAS, BRAF, and PIK3CA genes in the samples.

RESULTS

Together, we identified 1 silent mutation of HER2, 17 (43%) KRAS mutations, 1 (2.7%) BRAF mutation, and 4 (11%) mutations of PIK3CA in the IPMN/IPMC samples.

CONCLUSIONS

The EGFR and ERBB2 (HER2) mutations are very infrequent in IPMN/IPMC, suggesting the limited possibility of targeting mutated ERBB2 and EGFR for therapy for these lesions. The KRAS, BRAF, and PIK3CA, however, could represent interesting targets for future therapies in these lesions.

PIK3CA, KRAS, and BRAF mutations in intraductal papillary mucinous neoplasm/carcinoma (IPMN/C) of the pancreas

BACKGROUND AND AIMS

Recent studies have reported high frequencies of somatic mutations in the phosphoinositide-3-kinase catalytic-alpha (PIK3CA) gene in various human tumors. Three hot-spot mutations in the exons 9 and 20 have been proven to activate the Akt signalling pathway. The Raf/MEK/ERK (mitogen-activated protein kinase) signal transduction is an important mediator of a number of cellular fates including growth, proliferation, and survival. The BRAF gene is activated by oncogenic RAS, leading to cooperative effects in cells responding to growth factor signals. Here we evaluate the mutational status of PIK3CA, KRAS, and BRAF in intraductal papillary mucinous neoplasm/carcinoma (IPMN/IPMNC) of the pancreas.

MATERIALS AND METHODS

Exons 1, 4, 5, 6, 7, 9, 12, 18, and 20 of PIK3CA, exons 1 of KRAS, and exons 5, 11, and 15 of BRAF were analyzed in 36 IPMN/IPMC and two mucinous cystadenoma specimens by direct genomic DNA sequencing.

RESULTS

We identified four somatic missense mutations of PIK3CA within the 36 IPMN/IPMC specimens (11%). One of the four mutations, H1047R, has been previously reported to be a hot-spot mutation. Furthermore, we found 17 (47%) KRAS mutations in exon 1 and one missense mutation (2.7%) in exon 15 of BRAF.

CONCLUSION

This data is the first report of PIK3CA mutation in pancreatic cancer and it appears to be the first oncogene to be mutated in IPMN/IPMC but not in conventional ductal adenocarcinoma of the pancreas. Our data provide evidence that PIK3CA and BRAF contribute to the tumorigenesis of IPMN/IPMC, but at a lower frequency than KRAS.

[Intraductal papillary mucinous tumor: diagnostic and therapeutic approach]

Primary cystic pancreatic neoplasms are rare tumors, with an approximate prevalence of 10% of cystic pancreatic lesions. Most of these lesions correspond to mucinous cystic neoplasm, serous cystoadenoma and intraductal papillary mucinous tumor (IPMT). IPMT is characterized by diffuse dilatation of the main pancreatic duct and/or side branches with inner defects related to mucin or tumor, or mucin extrusion from a patent ampulla. IPMT has a low potential for malignancy, with a low growth rate, a low rate of metastatic spread and postsurgical recurrence. Over the last few years, major advances have been made in the diagnostic and therapeutic management of this tumor.

Survival and prognosis of invasive intraductal papillary mucinous neoplasms of the pancreas: comparison with pancreatic ductal adenocarcinoma

OBJECTIVES

Invasive intraductal papillary mucinous neoplasm (IPMN) of the pancreas is often considered to have a better prognosis than pancreatic ductal adenocarcinoma. The aim of this study was to evaluate and compare the prognosis and clinicopathologic features between 2 groups.

METHODS

Clinicopathologic features and long-term outcome of 32 patients with invasive IPMN were retrospectively evaluated and compared with those of 332 patients with pancreatic ductal adenocarcinoma.

RESULTS

Asymptomatic patients were more frequently observed in the group of invasive IPMN than ductal adenocarcinoma (28% vs 11%, P = 0.013). The distribution of stages of invasive IPMN was as follows: stage I (n = 10, 31%), II (n = 8, 25%), III (n = 3, 9%), and IV (n = 11, 34%). Among 19 patients who underwent resection for invasive IPMN, 10 (53%), 1 (5%), 1 (5%), and 2 (11%) had T1 stage tumors and tumor with lymph node metastasis, lymphatic, and perineural invasions, respectively, which were significantly infrequently observed compared with those with ductal adenocarcinoma. The 5-year survival rate of invasive IPMN was 33.9% compared with 9% of ductal adenocarcinoma (P = 0.011). The difference in the mean survival rates between invasive IPMN and ductal adenocarcinoma in patients without metastasis was also significant but not in patients with metastasis. During the median follow-up period of 18.4 months, 3 patients (16%) had a recurrence after resection for invasive IPMN.

CONCLUSIONS

Both the less aggressive pathological factors concerned with tumor invasiveness and early diagnosis of invasive IPMN contribute to higher survival rates of invasive IPMN than ductal adenocarcinoma. However, the prognosis of metastatic invasive IPMN is as poor as that of ductal adenocarcinoma.

Malignant intraductal papillary mucinous neoplasm of the pancreas: in situ versus invasive carcinoma surgical resectability

PURPOSE

To retrospectively evaluate computed tomographic (CT) findings in patients with in situ and invasive malignant intraductal papillary mucinous neoplasms (IPMNs) of the pancreas and to evaluate the accuracy for surgical resectability, with surgery and pathologic analysis as the reference standards.

MATERIALS AND METHODS

Institutional review board approval was obtained, and the informed consent requirement was waived. Forty-six patients with malignant IPMN proved at pathologic examination of the surgically resected specimen (n = 44) or laparotomy (n = 2) underwent surgery after multidetector CT was performed. CT findings were retrospectively evaluated to determine if a pancreatic malignant IPMN tumor was present; to make this determination, CT criteria were used to differentiate in situ from invasive tumors and signs of unresectability (liver metastasis, vascular CT pattern of encasement, or regional lymph node metastasis). The extent of the vascular CT pattern of encasement was recorded for each patient (no obliteration of the fat plane, obliteration of the fat plane of <50%, or obliteration of the fat plane of > or =50%). Statistical analysis was performed with the chi(2) and Student t tests.

RESULTS

CT revealed a mural nodule in the pancreatic duct wall in 14 patients with in situ carcinoma and one patient with invasive carcinoma (P < .003). CT revealed an infiltrative pancreatic mass in 17 patients with invasive carcinoma and two patients with in situ carcinoma (P < .02). Of the mural nodules, 93% were seen in patients with in situ carcinoma, whereas 90% of infiltrative pancreatic masses were observed in patients with invasive carcinomas. The positive predictive value of CT for determining resectability was 100%, and the overall accuracy of CT for determining resectability and unresectability was 74%. The positive predictive value of CT for determining unresectability was 17%, mainly owing to overestimation of arterial invasion.

CONCLUSION

CT is helpful in the differentiation of in situ and invasive IPMN. Classic vascular invasion criteria lead to the overestimation of surgical tumor unresectability in patients with malignant IPMN.

Predictive factors of malignant or invasive intraductal papillary-mucinous neoplasms of the pancreas

The aim of this study was to identify useful preoperative diagnostic findings indicative of malignant or invasive intraductal papillary-mucinous neoplasms (IPMN) of the pancreas to determine an optimal operative procedure for IPMN. Sixty-two IPMNs, which consisted of 29 adenomas, 10 borderline tumors, 11 adenocarcinomas in situ, and invasive adenocarcinomas were reviewed from 1990 to 2003. Preoperative predictive factors of malignant or invasive IPMN were analyzed among 10 factors by univariate and multivariate analysis. Diameter of the main pancreatic duct (> or =6 mm) and cytological examination of the pancreatic juice (the presence of malignant cells) were identified as independent predictive factors of malignant IPMN, and only cytological examination of the pancreatic juice (the presence of malignant cells) was identified as an independent predictor of invasive IPMN by multivariate analysis (P < 0.05). There was no recurrent disease in patients with adenoma and adenocarcinoma in situ, whereas recurrences occurred in 6 of 12 patients with invasive IPMN. Patient survival in noninvasive IPMN was significantly (P = 0.018) better than that in invasive IPMN (The overall 5-year survival rates were 87.2% and 49.2%, respectively). These results might be useful for selecting an optimal surgical procedure for IPMN.

Total pancreatectomy: indications, operative technique, and postoperative sequelae

Total pancreatectomy has been used to treat both benign and malignant disease of the pancreas, but its use has been limited by concerns about management of the a-pancreatic state with its attendant total endocrine and exocrine insufficiency. Here, we review the indications for total pancreatectomy, operative technique, and improvements in the postoperative management of patients. Total pancreatectomy remains a viable option in the treatment of intractable pain associated with chronic pancreatitis, multicentric or extensive neuroendocrine tumors, patients with familial pancreatic cancer with premalignant lesions, and in patients with intraductal papillary mucinous neoplasia with diffuse ductal involvement or invasive disease. Improvements in postoperative management include auto-islet cell transplantation, advances in insulin formulations, and the use of glucagon rescue therapy which allow much tighter control of blood glucose than previously possible. This markedly lessens the risk of life-threatening hypoglycemia and decreases the risk of long-term complications, resulting in improved quality of life for these patients.

Intraductal papillary mucinous tumour of the pancreas: differentiation of malignancy and benignancy by CT

AIM

To retrospectively identify signs predictive of malignant intraductal papillary mucinous tumour (IPMT) of the pancreas on computed tomography (CT) images.

MATERIALS AND METHODS

Thirty-four benign and 21 malignant pancreatic IPMTs were evaluated. Preoperative helical CT images in these 55 cases of pathologically proven pancreatic IPMT were reviewed by two radiologists unaware of the histological grading. Tumour morphological types, locations, numbers and sizes of cystic lesions, maximum main pancreatic duct diameters, the presence of septa, mural nodule, wall thickening, and calcification in cysts, communication with the main pancreatic duct, peripancreatic haziness, protrusion of duodenal papilla, pancreatic atrophy, lymphadenopathy and distant metastasis were analysed using univariate and multivariate analysis.

RESULTS

Main duct IPMTs were more likely to be malignant (71%) than branch duct (23%) or combined type IPMTs (28%; p=0.002). Among the branch duct type and combined types, large cystic lesion (p=0.018), the presence of a mural nodule (p=0.018), a thickened wall (p=0.009), and peripancreatic haziness (p=0.039) were found to predict malignancy.

CONCLUSION

CT is helpful in the preoperative differentiation of malignant and benign pancreatic IPMT. The presence of a dilated main pancreatic duct, mural nodules, thickened wall and peripancreatic haziness may be used as independent predictive signs of malignancy.