Intraductal papillary mucinous neoplasms of the pancreas

Double cystic brain metastasis in a patient with stable pancreatic intraductal papillary mucinous neoplasm

BACKGROUND

Brain metastases in pancreatic cancer are a rare condition and are usually seen in case of pancreatic adenocarcinoma. Only few cases of brain metastasis in patients affected by Intraductal papillary mucinous neoplasm (IPMN) are actually reported.

CASE DESCRIPTION

We report a patient diagnosed with double cystic brain lesions that the histological examination reveal to be consistent, with pancreatic metastasis. Our patient had an history shown of stable pancreatic IPMN which has never made the oncologist suspicious about neoplastic progression or degeneration into pancreatic carcinoma. Considering the rarity of these metastasis we did a literature review on the topic.

CONCLUSIONS

Despite rare, pancreatic origin of a cystic brain metastasis should considered in differential diagnosis in both patient with IPMN or patient with unknown primitive tumor.

Intraductal Oncocytic Papillary Neoplasms of the Pancreas

Intraductal oncocytic papillary neoplasms (IOPNs) are cystic neoplasms with intraductal growth and complex papillae composed of oncocytic cells. IOPNs have been reported both in the pancreas and biliary tree, and are most likely closely related in these 2 locations. In the pancreas, these rare tumors are now considered 1 of the 4 histologic subtypes of intraductal papillary mucinous neoplasm (IPMN). Significant differences in histology, immunophenotype, and molecular genetics have been reported between IOPNs and other IPMN subtypes. However, there are limited data regarding the clinical behavior and prognosis of IOPNs in comparison to other subtypes of IPMN. We review features of pancreatic IOPNs and discuss the differential diagnosis of other intraductal lesions in the pancreas.

Single-operator pancreatoscopy is helpful in the evaluation of suspected intraductal papillary mucinous neoplasms (IPMN)

BACKGROUND AND OBJECTIVE

Even when advanced cross-sectional imaging modalities have been employed, endoscopic evaluation of intraductal papillary mucinous neoplasms (IPMN) is often required in order to assess the final character and extent of lesions. The current study addresses the use of SpyGlass single-operator peroral pancreatoscopy in suspected IPMN.

DESIGN

A prospective, non-randomized exploratory cohort study.

SETTING

Single-center.

PATIENTS AND INTERVENTION

A prospective study-cohort of 44 consecutive patients in a single tertiary referral center who underwent ERCP and peroral pancreatoscopy, was prospectively collected between July 2007 and March 2013 because of a radiological signs of IPMN. These IPMN-findings were discovered incidentally in 44% of the cases.

MAIN OUTCOME MEASUREMENTS

Diagnostic accuracy (specificity & sensitivity) and complications.

RESULTS

The targeted region of the pancreatic duct was reached with the SpyGlass system in 41 patients (median age 65 years, 41% female). Three patients were excluded from analysis because of failed deep cannulation of the pancreatic duct. Brush cytology was taken in 88% and direct biopsies in 41%. IPMN with intermediate or high-grade dysplasia was the main final diagnosis (76%) in 22 patients who had surgery. Out of the 17 patients with a final diagnosis of MD-IPMN, 76% were correctly identified by pancreatoscopy. Of the 9 patients with a final diagnosis of BD-IPMN, the pancreatoscopy identified 78% of the cases correctly.The incidence of post-ERCP pancreatitis was 17%. Pancreatoscopy was found to have provided additional diagnostic information in the vast majority of the cases and to affect clinical decision-making in 76%.

LIMITATIONS

Single-center study.

CONCLUSIONS

Single-operator peroral pancreatoscopy contributed to the clinical evaluation of IPMN lesions and influenced decision-making concerning their clinical management. The problem of post-procedural pancreatitis needs further attention.

Loss of PTEN expression is associated with poor prognosis in patients with intraductal papillary mucinous neoplasms of the pancreas

PURPOSE

Previously, we reported PIK3CA gene mutations in high-grade intraductal papillary mucinous neoplasms (IPMN). However, the contribution of phosphatidylinositol-3 kinase pathway (PI3K) dysregulation to pancreatic carcinogenesis is not fully understood and its prognostic value unknown. We investigated the dysregulation of the PI3K signaling pathway in IPMN and its clinical implication.

EXPERIMENTAL DESIGN

Thirty-six IPMN specimens were examined by novel mutant-enriched sequencing methods for hot-spot mutations in the PIK3CA and AKT1 genes. PIK3CA and AKT1 gene amplifications and loss of heterozygosity at the PTEN locus were also evaluated. In addition, the expression levels of PDPK1/PDK1, PTEN, and Ki67 were analyzed by immunohistochemistry.

RESULTS

Three cases carrying the E17K mutation in the AKT1 gene and one case harboring the H1047R mutation in the PIK3CA gene were detected among the 36 cases. PDK1 was significantly overexpressed in the high-grade IPMN versus low-grade IPMN (P = 0.034) and in pancreatic and intestinal-type of IPMN versus gastric-type of IPMN (P = 0.020). Loss of PTEN expression was strongly associated with presence of invasive carcinoma and poor survival in these IPMN patients (P = 0.014).

CONCLUSION

This is the first report of AKT1 mutations in IPMN. Our data indicate that oncogenic activation of the PI3K pathway can contribute to the progression of IPMN, in particular loss of PTEN expression. This finding suggests the potential employment of PI3K pathway-targeted therapies for IPMN patients. The incorporation of PTEN expression status in making surgical decisions may also benefit IPMN patients and should warrant further investigation.

Classification, morphology and molecular pathology of premalignant lesions of the pancreas

Over the past few years there have been substantial advances in our knowledge of premalignant lesions of the pancreas. Given the dismal prognosis of untreated pancreatic cancer, and the small proportion of patients who are operative candidates, an understanding of these premalignant lesions is essential for the development of strategies for early diagnosis and prevention. The 2010 WHO classification has added new entities, including intraductal tubular papillary neoplasms (ITPNs), and clarified the nomenclature and grading of previously recognised precursor lesions of pancreatic adenocarcinoma, such as intraductal papillary mucinous neoplasms (IPMNs), mucinous cystic neoplasms (MCNs) and pancreatic intraepithelial neoplasia (PanIN). In particular, there has been an upsurge of interest in the natural history of IPMN, driven partly by improvements in imaging modalities and the consequent apparent increase in their incidence, and partly by recognition that subtypes based on location or histological appearance define groups with significantly different behaviours. In mid 2012 revised international guidelines for the classification and management of IPMNs and MCNs were published, although in several respects these guidelines represent a consensus view rather than being evidence-based. In recent years major advances in molecular technologies, including whole-exome sequencing, have significantly enhanced our knowledge of pancreatic premalignancy and have identified potentially highly specific diagnostic biomarkers such as mutations in GNAS and RNF43 that could be used to pre-operatively assess pancreatic cysts.

Proposal for a morphological classification of intraductal papillary neoplasm of the bile duct (IPN-B)

PURPOSE

We propose a morphological classification of intraductal papillary neoplasm of the bile duct (IPN-B).

METHODS

A retrospective analysis of 16 patients with IPN-B who had undergone surgical resection was conducted. These 16 cases were classified into three types based on the primary lesion's anatomical location: branch duct type (6 cases), main duct type (5 cases) and mixed type (5 cases). In this paper we have analyzed the characteristics of IPN-B according to our new classification.

RESULTS

All branch duct type IPN-B was located in the left lobe and 5 of them were resected by left hepatectomy without extrahepatic bile duct resection (EBDR). On the other hand, all patients with main duct and mixed type IPN-B underwent EBDR in addition to hepatectomy or pancreatoduodenectomy. Microscopically, 2 of 6 patients with branch duct type IPN-B had no malignant component and, in the remaining 4 patients, cancer invasion was restricted to within the ductal wall. There were no cases of branch duct type IPN-B with lymph node metastasis and superficial intraductal tumor spread. In contrast, all patients with main duct and mixed duct type IPN-B had the malignant component. In all cases, lymph node metastasis was not observed, but superficial intraductal tumor spread was frequently found in extrahepatic bile duct lesions: 3 of main duct type and 3 of mixed type. Four patients with superficial intraductal spread had non-curative resection due to a cancer-positive ductal margin. Most patients with IPN-B obtained a good prognosis, but two patients with a cancer-positive ductal margin developed local recurrence.

CONCLUSIONS

Our classification vividly reflects clinical and pathological characteristics of IPN-B and is useful to determine appropriate surgical strategy.

Oncocytic-type intraductal papillary mucinous neoplasm (IPMN)-derived invasive oncocytic pancreatic carcinoma with brain metastasis - a case report

Pancreatic cancer is a lethal disease without effective treatments at present. It ranks as s as 4^th and 5^th in cancer-related mortality in the western countries and worldwide. Locally advanced pancreatic duct carcinoma (PDAC) and metastatic PDAC, usually found the metastases over liver, peritoneum, or lung, have been shown to be with dismal prognosis. Brain metastasis is a rare entity and most cases reported before were found post-mortem. Intraductal papillary mucinous neoplasms of the pancreas (IPMN) has been deemed as a precursor of PDAC with very slow progression rate. Here we reported a case diagnosed with IPMN-derived PDAC with brain metastasis. After surgeries for PDAC and brain metastasis, subsequent chemotherapy and radiotherapy were also given. One and half year after surgery, this patient is still living with good performance status, which may warrant individualization of therapeutic strategy for PDAC with only brain metastasis.

Intraductal papillary mucinous neoplasia (IPMN) of the pancreas: its diagnosis, treatment, and prognosis

BACKGROUND

The many varieties of cystic pancreatic tumor, and especially intraductal papillary mucinous neoplasia (IPMN), have attracted increased attention recently. Their incidence may be rising, and their histopathological evaluation and classification have become more precise than before.

METHODS

We discuss the current diagnostic evaluation of IPMN, along with treatment and prognostication, on the basis of the current international guideline as well as pertinent literature retrieved by a selective PubMed search.

RESULTS

The preoperative diagnostic evaluation of IPMN is often problematic. In particular, it may not be possible to differentiate main-duct disease from branch-duct disease (MD-IPMN vs. BD-IPMN) before surgery--a distinction with implications for prognosis and treatment, as MD-IPMN is more often malignant. An IPMN adenoma can develop into invasive pancreatic cancer. Because firm diagnostic criteria are still lacking, it is recommended that all MD-IPMN lesions and all large BD-IPMN lesions should be resected. Partial pancreatectomy with clean margins is the treatment of choice.

CONCLUSION

As IPMN seems to be a slow-growing precursor of pancreatic cancer, it is possible that its early detection and surgical treatment can lead to a cure. No conclusion about the efficacy of surveillance and follow-up programs can be drawn from the available evidence. A better understanding of the natural course of IPMN and the biology of pancreatic cancer is needed to enable further improvements in diagnosis and treatment.

Imaging IPMN: take home messages and news

IPMN is a frequent disease involving pancreatic duct. This disease could be malignant (parenchymal invasive adenocarcinoma), particularly if the main pancreatic duct is involved (this involvement is considered present if > 6 mm), if this enlargement reaches 10 mm or more, and if the pathological phenotype is biliopancreatic or intestinal (malignancy is less frequent if gastric one). Invasiveness is suspected if hypodense parenchymal lesion is present, particularly near a cystical lesion or MPD, a mural nodule of the wall, or if MPD wall has got a contrast uptake. Mural nodules inside cystic branch duct are associated with in situ grade 3 malignancies. MPD IPMN must be resected to prevent malignancy. The follow-up of isolated branch duct cysts relies upon MDCT and MRI, every two years if lesion is less than 1cm. Every one year if bigger, particularly if more than to 3 cm.

Cystic precursors to invasive pancreatic cancer

Improvements in the sensitivity and quality of cross-sectional imaging have led to increasing numbers of patients being diagnosed with cystic lesions of the pancreas. In parallel, clinical, radiological, pathological and molecular studies have improved the systems for classifying these cysts. Patients with asymptomatic serous cystic neoplasms can be managed conservatively with regular monitoring; however, the clinical management of patients with intraductal papillary mucinous neoplasms and mucinous cystic neoplasms is far more challenging, as it is difficult to determine whether these lesions will progress to malignancy. Fortunately, prospective studies have helped to establish that proposed clinical and radiological criteria (the Sendai guidelines) can be used to guide the care of patients with cystic lesions of the pancreas. Despite this progress in imaging and clinical guidelines, sensitive and specific tests have not yet been developed that can reliably predict the histology and biological properties of a cystic lesion. Such biomarkers are urgently needed, as noninvasive precursors of pancreatic cancer are curable, while the vast majority of invasive pancreatic adenocarcinomas are not.

Acute pancreatitis in patients operated on for intraductal papillary mucinous neoplasms of the pancreas: frequency, severity, and clinicopathologic correlations

OBJECTIVES

Acute pancreatitis (AP) may reveal intraductal papillary mucinous neoplasms of the pancreas (IPMN). The aims were to describe the characteristics of AP associated with IPMN and to compare patients with AP with those without AP.

METHODS

All patients who underwent surgery for IPMN between 1995 and 2006 were retrospectively studied. Clinical, imaging, and histological data were collected. The clinical and radiological severity of AP, the number of episodes, and recurrence after surgery were assessed.

RESULTS

One hundred eighty-five patients were included. Sixty-four (34.6%) had at least 1 AP (median, 2; range, 1-10). The median Balthazar score was 1 (0-6). Imaging analysis showed no difference between the 2 groups except for the presence of a mass. Branch duct IPMNs were more frequent in the AP group (74.4% vs 45.3%, P = 0.001), whereas combined IPMNs were more frequent in the non-AP group (45.3% vs 21.5%, P = 0.001). There was no difference in the grade of dysplasia between AP and non-AP groups: carcinoma, 45.3% versus 56.2%; benign IPMN, 54.7% versus 43.8% (P = NS), respectively.

CONCLUSIONS

Acute pancreatitis occurs in 34.6% of patients with IPMNs. Acute pancreatitis is not severe and often recurs. Histology showed no difference between the 2 groups.

Intraductal oncocytic papillary neoplasms of the pancreas and bile ducts: a description of five new cases and review based on a systematic survey of the literature

BACKGROUND

Intraductal oncocytic papillary neoplasms (IOPN) are rare tumors of the pancreatic and biliary ductal system. It is not absolutely clear if the molecular and clinicopathologic characteristics of IOPN differ significantly from other related lesions, namely intraductal papillary mucinous neoplasms (IPMN). Therefore it is not clear if it is reasonable to consider IOPN as a separate diagnostic and clinical entity.

METHODS

In order to describe the clinicopathologic characteristics of IOPN and to compare them with the IPMN profile, we performed a systematic review of the literature and additionally studied five previously unreported IOPN cases.

RESULTS

IOPN differ from IPMN by lack of K-ras gene mutations in all studied cases. Several differences in the clinical and biological profile between IOPN and IPMN exist, but they are of quantitative rather than of qualitative nature. Additionally, pancreaticobiliary or gastric-foveolar IPMN components may coexist with IOPN component within a single lesion, which suggests at least a partial relation of the pathogenetic pathways of IPMN and IOPN. Importantly, the pathogenesis of accumulation of mitochondria and oxyphilic appearance of IOPN remains unknown.

CONCLUSIONS

At present, there are no reliable criteria other than histopathological picture and K-ras gene status to differentiate IOPN from IPMN. In particular, no clear differences in optimal treatment options and prognosis between these tumors are known. Further studies are needed to clarify the biology of IOPN and to establish their position in clinicopathologic classifications of pancreatic tumors.

Pancreatic ductal adenocarcinomas in long-term follow-up patients with branch duct intraductal papillary mucinous neoplasms

OBJECTIVE

Although branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) are slow-growing tumors with a favorable prognosis, the synchronous occurrence of pancreatic ductal adenocarcinomas (PDAs) in patients with BD-IPMNs has been reported. This study was aimed to elucidate the development of PDAs in long-term follow-up patients with BD-IPMNs.

METHODS

We investigated 89 BD-IPMN patients who had no mural nodules and followed them up conservatively at least 2 years (median follow-up, 64 months; range, 25-158 months). All subjects underwent examinations by imaging modalities including endoscopic retrograde pancreatography. We calculated the standardized incidence ratio (SIR) from the vital statistics compiled by the Ministry of Health, Labor, and Welfare of Japan.

RESULTS

Among the 89 patients, 4 cases of PDAs distant from BD-IPMN were observed in 552 patient-years of follow-up (7.2 per 1000 patient-years). The expected number was 0.25, and the SIR of PDAs was 15.8 (95% confidence interval [CI], 4.3-40.4; P = 0.00014). Subgroup analyses showed that the incidence of PDAs was significantly increased in patients 70 years or older (SIR 16.7; 95% CI, 3.4-48.7; P = 0.0008) and in women (SIR 22.5; 95% CI, 2.7-81.1; P = 0.0037).

CONCLUSIONS

Patients with BD-IPMNs are at a high risk for PDAs. During the follow-up, careful examination is required to detect the development of PDAs in patients with BD-IPMNs.

[Differentiated therapy for intraductal papillary mucinous neoplasms]

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas are of increasing interest in the field of pancreatic surgery ever since their first description as an individual pancreatic tumor entity in 1982. The decision for surgical or conservative management is based on the adenoma-carcinoma sequence and the differentiation into main-duct or branch-duct IPMN. Invasive IPMN forms (carcinoma in situ and invasive carcinoma) and in particular noninvasive IPMNs (adenoma and borderline tumors) reveal significantly better survival rates than ductal adenocarcinoma of the pancreas.

Intraductal papillary mucinous neoplasms and other pancreatic cystic lesions

Pancreatic cystic neoplasms are being increasingly recognized, even in the absence of symptoms, in large part, due to markedly improved imaging modalities such as magnetic resonance imaging (MRI)/magnetic resonance cholangio pancreatography (MRCP) and computer tomography (CT) scanning. During the past 2 decades, better imaging of these cystic lesions has resulted in definition of different types, including pancreatic intraductal papillary mucinous neoplasms (IPMN). While IPMN represent only a distinct minority of all pancreatic cancers, they appear to be a relatively frequent neoplastic form of pancreatic cystic neoplasm. Moreover, IPMN have a much better outcome and prognosis compared to pancreatic ductal adenocarcinomas. Therefore, recognition of this entity is exceedingly important for the clinician involved in diagnosis and further evaluation of a potentially curable form of pancreatic cancer.