Intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasm mimicking a duodenal tumor

Intraductal papillary mucinous neoplasms of the pancreas are characterized by ductal dilatation, mucus secretion, and intraductal papillary growth. Intraductal papillary mucinous neoplasms can cause fistulation and extend to adjacent organs. However, they rarely present as large mass in the small bowel that causes bowel obstruction. Herein, we describe a case of intraductal papillary mucinous neoplasm that protruded into the duodenal lumen through the ampulla of Vater, presented as a large duodenal tumor, and developed duodenal obstruction. A 78-year-old woman was admitted to the emergency department with a 2-day history of vomiting and epigastric pain and 2 kg weight-loss in 2 months. Esophagogastroduodenoscopy showed a duodenal mass; however, the endoscope could not pass further, and visualization of the entire tumor was impossible. Computed tomography and magnetic resonance imaging revealed a heterogeneous enhancing mass measuring 8 cm in the second portion of the duodenum, which continued further as an intraductal mass of the pancreas. The main pancreatic duct was dilated, and the parenchyma was atrophied. The biopsy showed a well-differentiated adenocarcinoma and an intact overlying duodenal mucosa. Surgical option of treatment was offered to the patient; however, she refused it due to her advanced age and personal religious beliefs. Thus, we conclude that the experience and knowledge gathered through this patient regarding intraductal papillary mucinous neoplasms could provide further understanding of this disease and evolve subsequent patient care.

A Review of Mucinous Cystic and Intraductal Neoplasms of the Pancreatobiliary Tract

CONTEXT.—

Although most pancreatic and bile duct neoplasms are solid, mucinous cystic neoplasms and intraductal neoplasms have been increasingly recognized even when clinically silent, thanks to the increased use of sensitive imaging techniques. Cystic and intraductal neoplasms of the pancreas are often resectable and curable and constitute about 5% of all pancreatic neoplasms. Owing to their preinvasive nature and different biology, recognition of these entities remains a major priority. Mucinous cystic neoplasms are histologically and clinically distinct from other cystic pancreatic neoplasms. Pancreatic intraductal neoplasms encompass 3 major entities: intraductal papillary mucinous neoplasm, intraductal oncocytic papillary neoplasm, and intraductal tubulopapillary neoplasm. Intraductal papillary neoplasms of bile ducts are also preinvasive mass-forming neoplasms with both similarities and differences with their pancreatic counterparts. All of these pancreatobiliary neoplasms have diverse and distinctive clinicopathologic, genetic, and prognostic variations.

OBJECTIVE.—

To review the clinical, pathologic, and molecular features of mucinous cystic and intraductal neoplasms of the pancreatobiliary tract.

DATA SOURCES.—

Literature review, diagnostic manuals, and guidelines.

CONCLUSIONS.—

This review will briefly describe well-known clinical and pathologic features and will focus on selected recently described aspects of morphology, grading, classification, and genomic alterations of cystic and intraductal neoplasms of the pancreatobiliary tract.

Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors

Multidetector computed tomography (MDCT) is a widely used cross-sectional imaging modality for initial evaluation of patients with suspected pancreatic ductal adenocarcinoma (PDAC). However, diagnosis of PDAC can be challenging due to numerous pitfalls associated with image acquisition and interpretation, including technical factors, imaging features, and cognitive errors. Accurate diagnosis requires familiarity with these pitfalls, as these can be minimized using systematic strategies. Suboptimal acquisition protocols and other technical errors such as motion artifacts and incomplete anatomical coverage increase the risk of misdiagnosis. Interpretation of images can be challenging due to intrinsic tumor features (including small and isoenhancing masses, exophytic masses, subtle pancreatic duct irregularities, and diffuse tumor infiltration), presence of coexisting pathology (including chronic pancreatitis and intraductal papillary mucinous neoplasm), mimickers of PDAC (including focal fatty infiltration and focal pancreatitis), distracting findings, and satisfaction of search. Awareness of pitfalls associated with the diagnosis of PDAC along with the strategies to avoid them will help radiologists to minimize technical and interpretation errors. Cognizance and mitigation of these errors can lead to earlier PDAC diagnosis and ultimately improve patient prognosis.

Pancreatic sphincterotomy improves pain symptoms due to branch-duct intrapapillary mucinous neoplasia without worrisome features: a multicenter study

Introduction Branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) require follow-up to detect worrisome features (WF). Data are missing about endoscopic pancreatic sphincterotomy (PS) for symptomatic IPMN.

Patients and methods This was a retrospective multicenter study in four expert centers. Patients treated with endoscopic PS for symptomatic (painful) BD-IPMN without WF were included. Age, sex, follow-up time, characteristics of IPMNs and endoscopic retrograde cholangiopancreatographies (ERCPs), and indications for surgery were recorded.

Results In total, 21 patients were included (median age 68 years, range 45 – 87 years). The median number of cysts was 2 (range 1 – 10), located in the head (59 %), body/tail (17 %), or multifocal (24 %). ERCP including PS was completed in all of the cases, with biliary sphincterotomy in 33 %. Clinical efficacy after one session was 81 % (17/21). Among the failures, one had a second successful PS and three were operated. The final efficacy was 86 % (18/21). Seven patients were operated after a mean of 19 months: four for WF, three for pain. The histopathology showed four low grade dysplasia, one high grade dysplasia, and two no dysplasia. No adenocarcinoma occurred during a follow-up of 99 months (range 14 – 276 months).

Conclusions Endoscopic PS for symptomatic IPMN without WF is effective in more than 80 % of cases, without increasing the risk for adenocarcinoma.

Quantitative proteomic analysis of pancreatic cyst fluid proteins associated with malignancy in intraductal papillary mucinous neoplasms

Background

The application of advanced imaging technologies for identifying pancreatic cysts has become widespread. However, accurately differentiating between low-grade dysplasia (LGD), high-grade dysplasia (HGD), and invasive intraductal papillary mucinous neoplasms (IPMNs) remains a diagnostic challenge with current biomarkers, necessitating the development of novel biomarkers that can distinguish IPMN malignancy.

Methods

Cyst fluid samples were collected from nine IPMN patients (3 LGD, 3 HGD, and 3 invasive IPMN) during their pancreatectomies. An integrated proteomics approach that combines filter-aided sample preparation, stage tip-based high-pH fractionation, and high-resolution MS was applied to acquire in-depth proteomic data of pancreatic cyst fluid and discover marker candidates for IPMN malignancy. Biological processes of differentially expressed proteins that are related to pancreatic cysts and aggressive malignancy were analyzed using bioinformatics tools such as gene ontology analysis and Ingenuity pathway analysis. In order to confirm the validity of the marker candidates, 19 cyst fluid samples were analyzed by western blot.

Results

A dataset of 2992 proteins was constructed from pancreatic cyst fluid samples. A subsequent analysis found 2963 identified proteins in individual samples, 2837 of which were quantifiable. Differentially expressed proteins between histological grades of IPMN were associated with pancreatic diseases and malignancy according to ingenuity pathway analysis. Eighteen biomarker candidates that were differentially expressed across IPMN histological grades were discovered—7 DEPs that were upregulated and 11 that were downregulated in more malignant grades. HOOK1 and PTPN6 were validated by western blot in an independent cohort, the results of which were consistent with our proteomic data.

Conclusions

This study demonstrates that novel biomarker candidates for IPMN malignancy can be discovered through proteomic analysis of pancreatic cyst fluid.

Electronic supplementary material

The online version of this article (10.1186/s12014-018-9193-1) contains supplementary material, which is available to authorized users.

Analysis of clinical characteristics and treatment of pancreatic cystic tumors

Objective

To summarize experience in the diagnosis and treatment of pancreatic cystic neoplasms.

Methods

This is a retrospective study of 207 patients who were diagnosed with pancreatic cystic tumors at Peking Union Medical College Hospital between Jan 2009 and Mar 2014. Clinical data, such as clinical manifestations, radiological and pathological images and surgical recordings, were collected.

Results

Of the 207 included patients, females accounted for 76.81%, and the mean patient age was 52.04 years. Malignancy was more common in older patients who presented with marasmus and jaundice. Other risk factors included solid components in the tumor, a large tumor size, and elevated levels of tumor markers. Surgical treatment was required when a malignant tumor was suspected. The operation approach was selected based on the location, size and characteristics of the tumor. The position of the tumor relative to the pancreatic duct also played a significant role.

Conclusions

No specific symptoms were observed for the patients with pancreatic cystic tumors. Imaging played an important role in making a differential diagnosis. Furthermore, surgical treatment should be proposed for patients with significant symptoms and potentially malignant tumors. The tumor resection rate is high, suggestive of good prognosis.

Serum Carbohydrate Antigen 19-9 in Differential Diagnosis of Benign and Malignant Pancreatic Cystic Neoplasms: A Meta-Analysis

Background

Using serum carbohydrate antigen 19–9 (CA 19–9) in discriminating between benign and malignant pancreatic disease remains controversial. We aim to evaluate the diagnostic value of serum CA 19–9 in predicting malignant pancreatic cystic lesions.

Methods

Eligible studies were identified through searching MEDLINE and EMBASE prior to March 2016. Studies were assessed for quality using the Quality Assessment for Studies of Diagnostic Accuracy, 2nd version (QUADAS-2). Pooled sensitivity and specificity with 95% confidence interval (CI) were calculated using random-effects models. Summary receiver operator characteristic (SROC) curves and the area under curve (AUC) were performed.

Results

A total of thirteen studies including 1437 patients were enrolled in this meta-analysis. The pooled sensitivity and specificity were 0.47(95% CI: 0.35–0.59), and 0.88(95% CI: 0.86–0.91), respectively, and the AUC was 0.87(95% CI, 0.84–0.90). Meta-regression analysis showed that sample size, region and reference standards were not the main sources of heterogeneity.

Conclusions

Serum CA 19–9 has satisfying pooled specificity while poor pooled sensitivity for discriminating benign from malignant PCNs. It deserves to be widely used as complementary to other clinical diagnostic methods.

An observational and comparative study on intraductal papillary mucinous neoplasm of the biliary tract and the pancreas from a Chinese cohort

BACKGROUND

Intraductal papillary mucinous neoplasms of the biliary tract (BT-IPMNs) are unique but very rare biliary tumors. The relationship between BT-IPMNs and intraductal papillary mucinous neoplasm of the pancreas (P-IPMNs) was still unclear and controversial.

OBJECTIVE

We aimed to evaluate the clinical, radiological, histopathological, and prognostic characteristics of BT-IPMNs and P-IPMNs to achieve a better understanding of these two rare bilio-pancreatic diseases and their connections.

METHODS

Data of a total of 116 patients who were all surgically treated and histopathologically diagnosed as BT-IPMNs or P-IPMNs from January 2004 to December 2014 in our single institution was all retrospectively collected and analyzed.

RESULTS

This study respectively enrolled 32 patients with BT-IPMNs and 84 ones with P-IPMNs. The differences between BT-IPMNs and P-IPMNs in age, sex ratios, clinical presentation, elevated tumor markers and proportion of malignancy were not statistically significant (P>0.05), while the tumor diameter of BT-IPMNs was notably smaller than P-IPMNs (1.72cm, 4.56cm, respectively; P=0.028). Patients with BT-IPMNs were more likely manifest the symptoms of cholangitis, compared to those with P-IPMNs who showed pancreatitis (75%, 30%, respectively; P=0.039). Bile duct dilatation (100%), tumor of bile duct cavity (50%) or/and cystic dilatation of the bile duct (50%) were the typical manifestations of preoperative imaging examinations of BT-IPMNs, in which tumors were mainly located in intrahepatic or hepatic hilar region (26, 81%). Surgery has been the curable treatment for BT-IPMNs in which left hepatic lobectomy was the most commonly performed procedure (20, 63%). Finally, compared with P-IPMNs, the overall mean survival time of patients with BT-IPMNs was a little shorter (59.1mon, 86.7mon, respectively; P=0.002).

CONCLUSION

BT-IPMNs are a sort of rare and separate biliary tract neoplasm, which might be related with the stones of biliary tract or the infections of parasite. Although arising in different organs and representing different features, BT-IPMNs and P-IPMNs shared considerable clinical and pathological similarities which might represent related or similar development process in the bilio-pancreatic duct systems.

Intraductal papillary mucinous neoplasm in an annular pancreas: a case report

Annular pancreas is a rare anomaly in which a ring of pancreatic tissue encircles the second portion of the duodenum. We herein report a case involving a 79-year-old Japanese man with an intraductal papillary mucinous neoplasm (IPMN) of the pancreas. Imaging studies showed that the pancreatic tissue encircled the descending part of the duodenum and that a 30-mm-diameter cystic tumor was present in the annular segment, leading to the diagnosis of pancreatic IPMN. Limited pancreatic resection was successfully performed by careful division of the annular segment from the second portion of the duodenum. The postoperative course was uneventful, and the patient’s pancreatic function was retained without the need for supplementation. To the best of our knowledge, this is the first report of IPMN occurring in the annular segment of the pancreas. Limited resection of the pancreatic annular segment is a feasible surgical treatment for noninvasive IPMN of the annular pancreas.

Intraductal Papillary Mucinous Neoplasm of Pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are neoplasms that are characterized by ductal dilation, intraductal papillary growth, and thick mucus secretion. This relatively recently defined pathology is evolving in terms of its etiopathogenesis, clinical features, diagnosis, management, and treatment guidelines. A PubMed database search was performed. All the relevant abstracts in English language were reviewed and the articles in which cases of IPMN could be identified were further scrutinized. Information of IPMN was derived, and duplication of information in several articles and those with areas of persisting uncertainties were excluded. The recent consensus guidelines were examined. The reported incidence of malignancy varies from 57% to 92% in the main duct-IPMN (MD-IPMN) and from 6% to 46% in the branch duct-IPMN (BD-IPMN). The features of high-risk malignant lesions that raise concern include obstructive jaundice in a patient with a cystic lesion in the pancreatic head, the findings on radiological imaging of a mass lesion of >30 mm, enhanced solid component, and the main pancreatic duct (MPD) of size ≥10 mm; while duct size 5-9 mm and cyst size <3 mm are considered as “worrisome features.” Magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) are primary investigations in diagnosing and following up on these patients. The role of pancreatoscopy and the analysis of aspirated cystic fluid for cytology and DNA analysis is still to be established. In general, resection is recommended for most MD-IPMN, mixed variant, and symptomatic BD-IPMN. The 5-year survival of patients after surgical resection for noninvasive IPMN is reported to be at 77-100%, while for those with invasive carcinoma, it is significantly lower at 27-60%. The follow-up of these patients could vary from 6 months to 1 year and would depend on the risk stratification for invasive malignancy and the pathology of the resected specimen. The understanding of IPMN has evolved over the years. The recent guidelines have played a role in this regard.

Intraductal papillary mucinous neoplasms of the pancreas: evaluation of malignant potential and surgical resectability by using MR imaging with MR cholangiography

PURPOSE

To evaluate the diagnostic performance of magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP) in determining the malignant potential and surgical resectability of pancreas intraductal papillary mucinous neoplasms (IPMNs).

MATERIALS AND METHODS

Institutional review board approval was obtained, and the requirement for informed consent was waived. Ninety-eight patients with pathologically proved pancreas IPMNs who underwent MR imaging with MRCP comprised the study population. MR images were analyzed for findings suggestive of high-risk stigmata or worrisome features, as proposed by the international consensus guidelines 2012. Interobserver agreement between two experienced observers (observers 1 and 2) and one inexperienced observer (observer 3) was assessed. Diagnostic performance of MR imaging in the evaluation of the malignant potential and surgical resectability of IPMNs was analyzed in these three observers by using receiver operating curve analysis.

RESULTS

MR imaging with MRCP showed sensitivity of 83% (35/42), 79% (33/42), and 90% (38/42); specificity of 80% (41/51), 51% (26/51), and 24% (12/51); and accuracy of 82% (76/93), 63% (59/93), and 54% (50/93) for observers 1, 2, and 3, respectively, in the evaluation of the malignant potential of pancreas IPMNs when at least one worrisome feature was present. Interobserver agreement in the detection of intramural nodules (κ = 0.349-0.574), enhanced solid components (κ = 0.318-0.574), and measurement of main pancreatic duct diameter (intraclass correlation coefficient = 0.9477) was fair to high. The respective sensitivity, specificity, and accuracy in determination of surgical resectability were 95% (81/85), 99% (84/85), and 88% (75/85); 69% (9/13), 69% (9/13), and 54% (7/13); and 92% (90/98), 95% (93/98), and 84% (82/98) for observers 1, 2, and 3.

CONCLUSION

MR imaging with MRCP is a useful modality in the evaluation of the malignant potential and resectability of IPMNs, with high sensitivity and moderate specificity in the experienced radiologists but relatively low specificity in the inexperienced radiology trainee.

Total invasion of the pancreatic gland by a rare aggressive IPMN: Report of a case

INTRODUCTION

The intraductal papillary mucinous neoplasms (IPMNs) are increasingly diagnosed entities with high potential of malignancy and significant recurrence rates.

PRESENTATION OF CASE

In this case report a rare mixed IPMN with full invasion of the pancreatic ducts was identified.

DISCUSSION

Difficulties in determining the grade of pancreatic duct involvement make the surgical management tough.

CONCLUSION

In multifocal IPMNs the management of the patients is even more challenging. In this case the patient was treated successfully with total pancreatectomy.

Decision making for pancreatic resection in patients with intraductal papillary mucinous neoplasms

AIM: To identify a practical approach for preoperative decision-making in patients with intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.

METHODS: Between March 1999 and November 2006, the clinical characteristics, pathological data and computed tomography/magnetic resonance imaging (CT/MRI) of 54 IPMNs cases were retrieved and analyzed. The relationships between the above data and decision-making for pancreatic resection were analyzed using SPSS 13.0 software. Univariate analysis of risk factors for malignant or invasive IPMNs was performed with regard to the following variables: carcinoembryonic antigen, carbohydrate antigen 19-9 (CA19-9) and the characteristics from CT/MRI images. Receiver operating characteristic (ROC) curve analysis for pancreatic resection was performed using significant factors from the univariate analysis.

RESULTS: CT/MRI images, including main and mixed duct IPMNs, tumor size > 30 mm or a solid component appearance in the lesion, and preoperative serum CA19-9 > 37 U/mL had good predictive value for determining pancreatic resection (P < 0.05), but with limitations. Combining the above factors (CT/MRI images and CA19-9) improved the accuracy and sensitivity for determining pancreatic resection in IPMNs. Using ROC analysis, the area under the curve reached 0.893 (P < 0.01, 95%CI: 0.763-1.023), with a sensitivity, specificity, positive predictive value and negative predictive value of 95.2%, 83.3%, 95.2% and 83.3%, respectively.

CONCLUSION: Combining preoperative CT/MRI images and CA19-9 level may provide useful information for surgical decision-making in IPMNs.

Is it necessary to follow patients after resection of a benign pancreatic intraductal papillary mucinous neoplasm?

BACKGROUND

Little is known about the risk of subsequently developing a new or progressive intraductal papillary mucinous neoplasm (IPMN) after partial pancreatic resection of a noninvasive IPMN.

STUDY DESIGN

One hundred thirty patients with more than 1 year of follow-up after resection were included in this analysis.

RESULTS

At a median follow-up of 38 months, 22 (17%) developed imaging evidence of a new or progressive IPMN. Eleven (8%) underwent completion resection. Three of the 11 patients had invasive adenocarcinoma. Two other patients developed metastatic pancreatic adenocarcinoma and did not undergo resection. All 5 patients (4%) with cancer had negative margins at initial operation. Sixteen of 100 patients (16%) with negative margins for IPMN at the initial operation developed a new IPMN vs 6 of 30 patients (20%) with margins positive for IPMN (p = ns). Five of 22 patients (23%) with a new IPMN had a family history of pancreatic cancer, while 8 of 108 patients (7%) without a new IPMN had a family history (p < 0.05). Overall, the chances of developing a new IPMN at 1, 5, and 10 years after the initial surgery were 4%, 25%, and 62%, respectively, and of requiring surgery were 1.6%, 14%, and 18%, respectively. The estimated chances of developing invasive pancreatic cancer were 0%, 7%, and 38% at 1, 5, and 10 years, respectively.

CONCLUSIONS

Patients who have undergone resection for noninvasive IPMN require indefinite close surveillance because of the risks of developing a new IPMN, of requiring surgery, and of developing cancer. A family history of pancreatic cancer, but not margin status or degree of dysplasia, is associated with a risk of development of a new or progressive IPMN.

Intracholecystic papillary-tubular neoplasms (ICPN) of the gallbladder (neoplastic polyps, adenomas, and papillary neoplasms that are ≥1.0 cm): clinicopathologic and immunohistochemical analysis of 123 cases

The literature on the clinicopathologic characteristics of tumoral intraepithelial neoplasms (neoplastic polyps) of the gallbladder (GB) is fairly limited, due in part to the variability in definition and terminology. Most reported adenomas (pyloric gland type and others) were microscopic and thus regarded as clinically inconsequential, whereas papillary in situ carcinomas have been largely considered a type of invasive adenocarcinoma under the heading of "papillary adenocarcinomas." In this study, 123 GB cases that have a well-defined exophytic preinvasive neoplasm measuring ≥1 cm were analyzed. The patients were predominantly female (F/M=2:1) with a mean age of 61 y and a median tumor size of 2.2 cm. Half of the patients presented with pain, and in the other half the neoplasm was detected incidentally. Other neoplasms, most being gastrointestinal tract malignancies, were present in 22% of cases. Gallstones were identified in only 20% of cases. Radiologically, almost half were diagnosed as "cancer," roughly half with polypoid tumor, and in 10% the lesion was missed. Pathologic findings: (1) The predominant configuration was papillary in 43%, tubulopapillary in 31%, tubular in 26%. (2) Each case was assigned a final lineage type on the basis of the predominant pattern (>75% of the lesion) on morphology, and supported with specific immunohistochemical cell lineage markers. The predominant cell lineage could be identified as biliary in 50% (66% of which were MUC1), gastric foveolar in 16% (all were MUC5AC), gastric pyloric in 20% (92% MUC6), intestinal in 8% (100% CK20; 75% CDX2; 50%, MUC2), and oncocytic in 6% (17% HepPar and 17% MUC6); however, 90% of cases had some amount of secondary or unclassifiable pattern and hybrid immunophenotypes. (3) Of the cases that would have qualified as "pyloric gland adenoma," 21/24 (88%) had at least focal high-grade dysplasia and 18% had associated invasive carcinoma. Conversely, 8 of 47 "papillary adenocarcinoma"-type cases displayed some foci of low-grade dysplasia, and 15/47 (32%) had no identifiable invasion. (4) Overall, 55% of the cases had an associated invasive carcinoma (pancreatobiliary type, 58; others, 10). Factors associated significantly with invasion were the extent of high-grade dysplasia, cell type (biliary or foveolar), and papilla formation. Among systematically analyzed invasive carcinomas, tumoral intraepithelial neoplasia was detected in 6.4% (39/606). (5) The 3-year actuarial survival was 90% for cases without invasion and 60% for those associated with invasion. In contrast, those associated with invasion had a far better clinical outcome compared with pancreatobiliary-type GB carcinomas (3-yr survival, 27%), and this survival advantage persisted even with stage-matched comparison. Death occurred in long-term follow-up even in a few noninvasive cases (4/55; median 73.5 mo) emphasizing the importance of long-term follow-up. In conclusion, tumoral preinvasive neoplasms (≥1 cm) in the GB are analogous to their pancreatic and biliary counterparts (biliary intraductal papillary neoplasms, pancreatic intraductal papillary mucinous neoplasms, and intraductal tubulopapillary neoplasms). They show variable cellular lineages, a spectrum of dysplasia, and a mixture of papillary or tubular growth patterns, often with significant overlap, warranting their classification under 1 unified parallel category, intracholecystic papillary-tubular neoplasm. Intracholecystic papillary-tubular neoplasms are relatively indolent neoplasia with significantly better prognosis compared with pancreatobiliary-type GB carcinomas. In contrast, even seemingly innocuous examples such as those referred to as "pyloric gland adenomas" can progress to carcinoma and be associated with invasion and fatal outcome.

Interdisciplinary management of cystic neoplasms of the pancreas

Cystic neoplasms of the pancreas are increasingly recognized due to the frequent use of abdominal imaging. It is reported that up to 20% of abdominal cross-sectional scans identify incidental asymptomatic pancreatic cysts. Proper characterization of pancreatic cystic neoplasms is important not only to recognize premalignant lesions that will require surgical resection, but also to allow nonoperative management of many cystic lesions that will not require resection with its inherent morbidity. Though reliable biomarkers are lacking, a wide spectrum of diagnostic modalities are available to evaluate pancreatic cystic neoplasms, including radiologic, endoscopic, laboratory, and pathologic analysis. An interdisciplinary approach to management of these lesions which incorporates recent, specialty-specific advances in the medical literature is herein suggested.

[Strategy in intraductal papillary mucinous neoplasm of the pancreas]

Intraductal papillary mucinous neoplasm (IPMN) is a premalignant pancreatic entity characterized by papillary growth of the ductal epithelium with rich mucin production and cystic dilatation of the main pancreatic duct and/or its branches. These neoplasms are often multifocal. Preoperative distinction between benign and malignant lesions is important to select the most appropriate treatment and to improve prognosis. Early surgical resection is the treatment of choice to avoid malignant transformation when predictive factors for malignancy are present. These factors include localization, cyst greater than 3cm, nodules in the cystic wall, atypias in the cyst fluid and the presence of symptoms. The extent of resection required for adequate treatment of IPMN of the pancreas is still controversial. Patients who retain a portion of their pancreas following resection of an IPMN need to be followed up with periodic imaging to detect recurrences, signs indicating a risk of malignant transformation, and metachronous lesions. The existence of possible synchronous or metachronous lesions in other organs should also be investigated.

Outcomes of primary surveillance for intraductal papillary mucinous neoplasm

BACKGROUND

Limited data are available regarding the natural history of patients undergoing primary surveillance for intraductal papillary mucinous neoplasm (IPMN). We hypothesize that symptoms, radiologic characteristics, and cytopathology will predict cancer risk during surveillance.

METHODS

Between March 2002 and March 2010, 522 patients were diagnosed with IPMN at a single, high-volume institution. Low versus high oncologic risk was stratified prospectively. Patients with under 3 months of surveillance were excluded.

RESULTS

Two hundred ninety-two patients underwent primary surveillance for IPMN. Two hundred forty-four (84%) were classified as low-risk IPMN. Mean surveillance duration was 35 (4-99) months. Thirty (12%) patients initially stratified as low-risk developed a new indication for pancreatic resection. Only 28 underwent resection, and pathologic tissue analysis revealed 27 (96%) low-grade IPMN and one (4%) high-grade dysplastic IPMN. Overall, two (1%) patients initially determined to be low-risk developed invasive cancer. Forty-eight (16%) patients stratified as high-risk IPMN were initially managed nonoperatively. Of the 13 (27%) high-risk patients that died during follow-up, two (15%) died from pancreatic cancer.

CONCLUSIONS

Progression to pancreatic cancer during surveillance for low-risk IPMN was rare. Current indications for resection did not forecast malignancy. Poor operative candidates with high-risk IPMN progressed to invasive cancer more commonly, though a substantial portion succumbed to non-IPMN-related death.

Predictive value of serum carbohydrate antigen 19-9 in malignant intraductal papillary mucinous neoplasms

BACKGROUND

The goal of the present study was to evaluate the predictive value of serum carbohydrate antigen 19-9 (CA 19-9) in the diagnosis of malignant intraductal papillary mucinous neoplasms of pancreas (IPMNs).

METHODS

Eighty-six patients with pathological diagnosis of IPMNs in Zhongshan Hospital between March 1999 and November 2008 were retrospectively reviewed. Data reflecting clinical characteristics, tumor marker level, and prognosis were collected. The potential predictive value of CA 19-9 was analyzed by receiver operating characteristic (ROC) curve.

RESULTS

Eighty-six consecutive patients with IPMNs all underwent surgical intervention. A high level of CA 19-9 or carcinoembryonic antigen (CEA) was associated with more advanced stage of malignant IPMNs. Carbohydrate antigen 19-9 was significant for judging malignant IPMNs in the binary logistic regression model (p=0.047). The hazard ratio was 1.014, whose 95.0% confidence interval was 0.91-1.028. Receiver operating characteristic analysis showed that the serum CA 19-9 level had good predictive value for malignant or invasive IPMNs, postoperative survival, and disease-specific recurrence. The area under the curve (AUC) was 0.856, 0.893, 0.815, and 0.857 (p<0.05), respectively. According to the follow-up, mean survival time for groups with CA 19-9>63.60 U/ml was dramatically shorter than that for groups with CA 19-9≤63.60 U/ml (57.38±2.85 versus 29.24±5.82 [months]; p<0.01).

CONCLUSIONS

Serum CA 19-9 level has good predictive value for malignant or invasive IPMNs. Patients with CA 19-9 > 63.60 U/ml had poor postoperative prognosis in IPMNs. Preoperative abnormal serum CA 19-9 might be predictive for an aggressive surgical intervention in IPMNs.

Progress in research of intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasms (IPMNs) represent a spectrum of neoplasms arising from the main pancreatic duct or branch ducts and producing mucin and can be regarded as a type of precancerous lesions. Thanks to improvements in endoscopy and imaging techniques, IPMNs are being diagnosed with increasing frequency. However, there are currently no highly sensitive and specific preoperative criteria available to distinguish benign IPMNs from malignant ones. What's more, the necessity for EUS and ERCP in the diagnosis of IPMNs is still under debate. Here, we review recent advances in research of IPMNs and summarize potential differences between benign and malignant IPMNs.

Intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasm (IPMN) is a grossly visible (≥1 cm), mucin-producing neoplasm that arises in the main pancreatic duct and/or its branches. Patients with intraductal papillary mucinous neoplasm can present with symptoms caused by obstruction of the pancreatic duct system, or they can be asymptomatic. There are 3 clinical subtypes of intraductal papillary mucinous neoplasm: main duct, branch duct, and mixed. Five histologic types of intraductal papillary mucinous neoplasm are recognized: gastric foveolar type, intestinal type, pancreatobiliary type, intraductal oncocytic papillary neoplasm, and intraductal tubulopapillary neoplasm. Noninvasive intraductal papillary mucinous neoplasms are classified into 3 grades based on the degree of cytoarchitectural atypia: low-, intermediate-, and high-grade dysplasia. The most important prognosticator, however, is the presence or absence of an associated invasive carcinoma. Some main duct-intraductal papillary mucinous neoplasms progress into invasive carcinoma, mainly tubular adenocarcinoma (conventional pancreatic ductal adenocarcinoma) and colloid carcinoma. Branch duct-intraductal papillary mucinous neoplasms have a low risk for malignant transformation. Preoperative prediction of the malignant potential of an intraductal papillary mucinous neoplasm is of growing importance because pancreatic surgery has its complications, and many small intraductal papillary mucinous neoplasms, especially branch duct-intraductal papillary mucinous neoplasms, have an extremely low risk of progressing to an invasive cancer. Although most clinical decision making relies on imaging, a better understanding of the molecular genetics of intraductal papillary mucinous neoplasm could help identify molecular markers of high-risk lesions. When surgery is performed, intraoperative frozen section assessment of the pancreatic resection margin can guide the extent of resection. Intraductal papillary mucinous neoplasms are often multifocal, and surgically resected patients should be followed for metachronous disease.

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.

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.

Cystic neoplasms of the pancreas

Cystic neoplasms of the pancreas are a heterogeneous group of pancreatic tumors that vary in pathophysiology, malignant potential, clinical course, and outcomes. Their management is heavily predicated on establishing an accurate diagnosis. This can be particularly challenging, but can often be achieved by a thorough history and physical examination combined with high-quality, thin-slice computed tomography, although additional diagnostic tools may be required. Once the diagnosis is established, treatment can range from simple observation to total pancreatectomy. This decision rests on a clear and complete understanding of each disease process in the context of the patient's age and comorbidities. This article reviews the most common cystic neoplasms of the pancreas, focusing on their diagnosis and management.

Recurrence patterns of intraductal papillary mucinous neoplasms of the pancreas on enhanced computed tomography

OBJECTIVE

To characterize imaging features and findings in recurrent intraductal papillary mucinous neoplasms (IPMN); thereby reconciling the "field defect" theory with the appearance of recurrences distant from the resection margin.

METHODS

Computed tomography findings were reviewed in 89 patients who were resected with IPMN. At follow-up, the appearance of the pancreatic duct, features of recurrent masses, evidence of enhancement, calcifications, lymphadenopathy, and metastases were recorded.

RESULTS

Fourteen (16%) of the 89 patients had evidence of recurrence. Nine (64%) of the 14 patients demonstrated evidence for local recurrence. Ten recurrent lesions were noted in 9 patients. Patients with recurrence demonstrated an increase of pancreatic ductal dilatation of 3.3 mm, whereas patients without recurrence either had no dilatation or dilatation which then decreased over time.

CONCLUSIONS

Computed tomography findings suspicious for tumor recurrence include enlarging mass (either solid, cystic or both), progressive ductal dilatation, or extrapancreatic disease. There was a lack of correlation between margin status and location of recurrence within the pancreas consistent with the global field defect theory of IPMN.

[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.

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.

Branch duct intraductal papillary mucinous neoplasm of the pancreas in solid organ transplant recipients

OBJECTIVES

In immunosuppressed patients with branch duct intraductal papillary mucinous neoplasm (IPMN-Br) associated with solid organ transplantation, the risk of major pancreatic surgery has to be weighed against the risk of progression to malignancy. Recent studies show that IPMN-Br without consensus indications for resection (CIR) can be followed conservatively. We analyzed the course of IPMN-Br in patients with and without solid organ transplant.

METHODS

We compared clinical and imaging data at diagnosis and follow-up of 33 IPMN-Br patients with solid organ transplant (T-IPMN-Br) with those of 57 IPMN-Br patients who did not undergo transplantation (NT-IPMN-Br). In T-IPMN-Br, we noted pre- and post-transplant imaging and cyst characteristics. This case-control study was conducted in a tertiary-care hospital for patients with IPMN-Br.

RESULTS

T-IPMN-Br patients were younger than the NT-IPMN-Br patients (63 vs. 68 years, P = 0.01). The median duration of follow-up for the groups was similar (29 vs. 28 months, P = NS). CIR were present in 24% (8/33) of T-IPMN-Br patients and 32% (18/57) of NT-IPMN-Br. New CIR were noted in 6% (2/33) of patients in the T-IPMN-Br group during a median follow-up of 17 months (range, 3-100 months) compared with 4% (2/57) of patients in the NT-IPMN-Br group (P = NS). Eleven patients (10 NT-IPMN-Br, 1 T-IPMN-Br) underwent surgery during follow-up. Only one NT-IPMN-Br patient was diagnosed with malignancy; all others had benign IPMN-Br.

CONCLUSIONS

In participants with IPMN-Br, short-term follow-up after solid organ transplant was not associated with any significant change in cyst characteristics suggesting that incidental IPMN-Br, even in the setting of immunosuppression post-transplant, can be followed conservatively.

Agenesis of the dorsal pancreas and its association with pancreatic tumors

Morphogenesis of the pancreas is a complex process; nevertheless, congenital anomalies are rare. At embryogenesis, the pancreas develops from the endoderm-lined dorsal and ventral buds of the duodenum. The ventral bud gives rise to the lower head and uncinate process of the pancreas; whereas, the dorsal bud gives rise to the upper head, isthmus, body, and tail of the pancreas. Rarely, developmental failure of the dorsal pancreatic bud at embryogenesis results in the agenesis of the dorsal pancreas--neck, body, and tail. Even rarer is the association of pancreatic tumors with agenesis of the dorsal pancreas. In addition to citing our case, we provide a comprehensive review on agenesis of the dorsal pancreas and its association with pancreatic tumors.

Overview of the clinical problem: facts and current issues of mucinous cystic neoplasms of the pancreas

Pancreatic cystic lesions are uncommon and consist of pseudocysts, congenital cysts and cystic neoplasms including mucinous cystic neoplasms, intraductal papillary mucinous neoplasms and serous cystic neoplasms. Mucinous cystic neoplasms are large septated cysts without connection to the ductal system, characterised by the presence of thick-walled ovarian-type stroma and mucin. They occur predominantly in women and often are malignant. Therefore, surgical resection is recommended. Intraductal papillary mucinous neoplasms are neoplasms with tall, columnar, mucin-containing epithelium involving the main pancreatic ducts or major side branches. Intraductal papillary mucinous neoplasms occur in men and women in their 60s and 70s and may differentiate into malignant neoplasms. Therefore, surgical resection is mandatory. Serous cystic neoplasms appear as multiple cysts lined with cubic flat epithelium containing glycogen-rich cells with clear cytoplasm. They mainly occur in women in their 50s and are generally benign. Therefore, a conservative approach is recommended. As both mucinous cystic neoplasm and intraductal papillary mucinous neoplasms have a high malignant potential, it is important to differentiate between the various pancreatic cystic lesions. Several imaging techniques and tumour markers have been evaluated. Nonetheless, definitive guidelines to differentiate between serous cystic neoplasms, mucinous cystic neoplasms and intraductal papillary mucinous neoplasms are still poorly defined. A number of management issues regarding these neoplasms are still under debate, for example which imaging technique to use, differentiation between malignant or benign lesions and the preferred treatment modality for each pancreatic cystic neoplasm. Further research may lead to a definitive guideline for the diagnosis and treatment of mucinous cystic neoplasms, intraductal papillary mucinous neoplasms and serous cystic neoplasms.

Intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasm (IPMN) is characterized by enhanced mucus secretion. It is a benign or low-grade neoplasm associated with a dilated main pancreatic duct, patulous ampullary orifice, and abundant mucus secretion. Foci of aggressive cancer may arise and become invasive. Surgery is the only treatment that can cure IPMN, but the extent of pancreatic resection and the intraoperative margins remain areas of controversy. The risks of total pancreatectomy must be weighed against the risk for developing cancer in the residual pancreas. Risks must be factored against the natural course of the disease and the likelihood of malignancy developing over the life expectancy.

Intraductal papillary mucinous neoplasm--when to resect?

Based on the experience to date with IPMNs, the approach to patients remains relatively complex. A meticulous and careful approach to diagnosis, oncologic risk assessment, operative planning, and surveillance is needed to adequately address these lesions. Indications for resection in patients with IPMN are (1) cancer, (2) cancer prevention in patients at high risk for malignant transformation, and (3) management of symptoms. Differentiating patients who have IPMNs by type is an important initial step in providing optimal care (Fig. 6). In patients with MPD involvement (main- and mixed-type IPMN), the risk of malignancy at resection is too high to justify nonoperative management unless comorbidity or patient preference precludes operation. Until better preoperative biomarkers of malignancy in main duct-involved IPMNs are available, it is our recommendation that all patients who are fit should undergo resection of the entire involved segment with appropriate adjustment and extension based on intraoperative pathology. Total pancreatectomy may be indicated for diffuse main duct involvement. In the more difficult and debated cohort (i.e., patients with side branch disease only), a more strategic approach to whether to resect is appropriate. Patients with malignant cytopathology, concerning radiologic features (i.e., mural nodules, associated mass), or symptoms attributable to IPMNs should be offered resection. Importantly, specific symptoms have variable importance in terms of oncologic risk and are worth characterizing in individual patients. Size alone should not be the determining oncologic factor for resection, although we acknowledge that the literature is unclear in this regard. Size of IPMNs (or any other cystic lesion) may be a nononcologic indication to resect for symptom control and when size or anticipated growth may complicate the ability to safely extirpate the lesion. Other factors that should be considered in determining whether to resect are number of lesions, need for prolonged surveillance, inability to adequately perform noninvasive surveillance (e.g., contraindication to MRI), difficulty in surveillance (extensive/diffuse multifocal disease), and patient tolerance of risk. The decision to resect in patients undergoing primary surveillance or secondary surveillance for IPMN should be similar to the indications for primary resection noted previously. The optimal surveillance regimen, however, is unknown. The optimal surveillance regimen depends on the timing and incidence of "recurrence" and "new metachronous IPMIN development," which are not fully understood, partly because of suboptimal preoperative imaging in patients with IPMNs. To solve this mystery, surgeons and pancreatologists should be encouraged to obtain optimal and timely imaging studies before taking patients to the operating room. Patients should be followed at least annually with history and physical and optimal cross-sectional imaging. Endoscopy and cytopathologic assessment should be considered at least biannually and more often when indicated by patient symptoms or concerning radiographic features. The surveillance interval should be decreased and extent of testing increased based on patients with higher oncologic risk stratification. Although resection in patients undergoing surveillance currently follows the same algorithm as patients undergoing primary resection, assessment of the main pancreatic duct in patients undergoing secondary surveillance after segmental pancreatectomy (particularly pancreaticoduodenectomy) is complicated. Although new data continue to clarify how and when to approach IPMNs with segmental or total pancreatic resection, many questions remain unanswered. Continued efforts to uncover a more accurate natural history and behavior for IPMN continue to fill the gaps in our current understanding and practice. In the meantime, it is critical to educate and frequently restratify oncologic risk in patients based on optimal and timely data (history and physical and radiographic, endoscopic, and cytopathologic results) and rigorous follow-up to guide patients in reaching a decision of whether and when to undergo IPMN resection.