Pancreatic serous oligocystic adenomas: clinicopathologic features and a comparison with serous microcystic adenomas and mucinous cystic neoplasms

Role of Endoscopic Ultrasound in the Evaluation of Pancreatic Cystic Neoplasms: A Concise Review

Pancreatic cystic lesions are being discovered as incidental lesions during cross-sectional imaging studies of the abdomen with increasing frequency. Endoscopic ultrasound is an important diagnostic modality for managing pancreatic cystic lesions. There are various types of pancreatic cystic lesions, from benign to malignant. Endoscopic ultrasound has a multifactorial role in delineating the morphology of pancreatic cystic lesions, ranging from fluid and tissue acquisition for analysis-fine needle aspiration and through-the-needle biopsy, respectively-to advanced imaging techniques, such as contrast-harmonic mode endoscopic ultrasound and EUS-guided needle-based confocal laser endomicroscopy. In this review, we will summarize and provide an update on the specific role of EUS in the management of pancreatic cystic lesions.

Diagnostic, Structured Classification and Therapeutic Approach in Cystic Pancreatic Lesions: Systematic Findings with Regard to the European Guidelines

Due to the increasing use of cross-sectional imaging techniques and new technical possibilities, the number of incidentally detected cystic lesions of the pancreas is rapidly increasing in everyday radiological routines. Precise and rapid classification, including targeted therapeutic considerations, is of essential importance. The new European guideline should also support this. This review article provides information on the spectrum of cystic pancreatic lesions, their appearance, and a comparison of morphologic and histologic characteristics. This is done in the context of current literature and clinical value. The recommendations of the European guidelines include statements on conservative management as well as relative and absolute indications for surgery in cystic lesions of the pancreas. The guidelines suggest surgical resection for mucinous cystic neoplasm (MCN) ≥ 40 mm; furthermore, for symptomatic MCN or imaging signs of malignancy, this is recommended independent of its size (grade IB recommendation). For main duct IPMNs (intraductal papillary mucinous neoplasms), surgical therapy is always recommended; for branch duct IPMNs, a number of different risk criteria are applicable to evaluate absolute or relative indications for surgery. Based on imaging characteristics of the most common cystic pancreatic lesions, a precise diagnostic classification of the tumor, as well as guidance for further treatment, is possible through radiology.

“Honeycomb” appearance in large-duct type pancreatic ductal adenocarcinoma: Case report with radiologic–pathologic correlation

Large-duct type pancreatic ductal adenocarcinoma (PDA) is a rare morphologic variant forming large duct elements. This case report, to our knowledge, is the first report of a large-duct type PDA with a “honeycomb” appearance resembling a serous cystic neoplasm (SCN) on CT and MRI. The patient is an 82-year-old woman who presented with upper abdominal pain. Dynamic contrast-enhanced CT revealed a multilocular cyst with honeycomb loculi, in which the cyst walls showed gradual enhancement. On T2-weighted MRI, the mass displayed inhomogeneous hyperintensity characterized by a honeycomb appearance with irregular and thick hypointense cyst walls. The patient underwent distal pancreatectomy; histopathological diagnosis was large-duct type PDA. Although the imaging features of large-duct type PDA may resemble those of SCN, this distinction between PDA and SCN is important because the treatment options are very different.

Multi-Phase CT-Based Radiomics Nomogram for Discrimination Between Pancreatic Serous Cystic Neoplasm From Mucinous Cystic Neoplasm

Purpose

This study aimed to develop and verify a multi-phase (MP) computed tomography (CT)-based radiomics nomogram to differentiate pancreatic serous cystic neoplasms (SCNs) from mucinous cystic neoplasms (MCNs), and to compare the diagnostic efficacy of radiomics models for different phases of CT scans.

Materials and Methods

A total of 170 patients who underwent surgical resection between January 2011 and December 2018, with pathologically confirmed pancreatic cystic neoplasms (SCN=115, MCN=55) were included in this single-center retrospective study. Radiomics features were extracted from plain scan (PS), arterial phase (AP), and venous phase (VP) CT scans. Algorithms were performed to identify the optimal features to build a radiomics signature (Radscore) for each phase. All features from these three phases were analyzed to develop the MP-Radscore. A combined model comprised the MP-Radscore and imaging features from which a nomogram was developed. The accuracy of the nomogram was evaluated using receiver operating characteristic (ROC) curves, calibration tests, and decision curve analysis.

Results

For each scan phase, 1218 features were extracted, and the optimal ones were selected to construct the PS-Radscore (11 features), AP-Radscore (11 features), and VP-Radscore (12 features). The MP-Radscore (14 features) achieved better performance based on ROC curve analysis than any single phase did [area under the curve (AUC), training cohort: MP-Radscore 0.89, PS-Radscore 0.78, AP-Radscore 0.83, VP-Radscore 0.85; validation cohort: MP-Radscore 0.88, PS-Radscore 0.77, AP-Radscore 0.83, VP-Radscore 0.84]. The combination nomogram performance was excellent, surpassing those of all other nomograms in both the training cohort (AUC, 0.91) and validation cohort (AUC, 0.90). The nomogram also performed well in the calibration and decision curve analyses.

Conclusions

Radiomics for arterial and venous single-phase models outperformed the plain scan model. The combination nomogram that incorporated the MP-Radscore, tumor location, and cystic number had the best discriminatory performance and showed excellent accuracy for differentiating SCN from MCN.

CT-Based Radiomics Analysis for Preoperative Diagnosis of Pancreatic Mucinous Cystic Neoplasm and Atypical Serous Cystadenomas

Objectives

To investigate the value of CT-based radiomics analysis in preoperatively discriminating pancreatic mucinous cystic neoplasms (MCN) and atypical serous cystadenomas (ASCN).

Methods

A total of 103 MCN and 113 ASCN patients who underwent surgery were retrospectively enrolled. A total of 764 radiomics features were extracted from preoperative CT images. The optimal features were selected by Mann-Whitney U test and minimum redundancy and maximum relevance method. The radiomics score (Rad-score) was then built using random forest algorithm. Radiological/clinical features were also assessed for each patient. Multivariable logistic regression was used to construct a radiological model. The performance of the Rad-score and the radiological model was evaluated using 10-fold cross-validation for area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy.

Results

Ten screened optimal features were identified and the Rad-score was then built based on them. The radiological model was built based on four radiological/clinical factors. In the 10-fold cross-validation, the Rad-score was proved to be robust and reliable (average AUC: 0.784, sensitivity: 0.847, specificity: 0.745, PPV: 0.767, NPV: 0.849, accuracy: 0.793). The radiological model performed slightly less well in classification (average AUC: average AUC: 0.734 sensitivity: 0.748, specificity: 0.705, PPV: 0.732, NPV: 0.798, accuracy: 0.728.

Conclusions

The CT-based radiomics analysis provided promising performance for preoperatively discriminating MCN from ASCN and showed good potential in improving diagnostic power, which may serve as a novel tool for guiding clinical decision-making for these patients.

Changing trends in the clinicopathological features, practices and outcomes in the surgical management for cystic lesions of the pancreas and impact of the international guidelines: Single institution experience with 462 cases between 1995-2018

INTRODUCTION

The impact on clinical practice of the international guidelines including the Sendai Guidelines (SG06) and Fukuoka Guidelines (FG12) on the management of cystic lesions of the pancreas (CLP) has not been well-studied. The primary aim was to examine the changing trends and outcomes in the surgical management of CLP in our institution over time and to determine the impact of these guidelines on our institution practice.

METHODS

462 patients with surgically-treated CLP were retrospectively reviewed and classified under the 2 guidelines. The cohort was divided into 3 time periods: 1998-2006, 2007-2012 and 2013 to 2018.

RESULTS

Comparison across the 3 time periods demonstrated significantly increasing frequency of older patients, asymptomatic CLP, male gender, smaller tumor size, elevated Ca 19-9, use of magnetic resonance imaging (MRI) and use of endoscopic ultrasound (EUS) prior to surgery. There was also significantly increasing frequency of adherence to the international guidelines as evidenced by the increasing proportion of HR^SG06 and HR^FG12 CLP with a corresponding lower proportion of LR^SG06 and LR^FG12 being resected. This resulted in a significantly higher proportion of resected CLP whereby the final pathology confirmed that a surgery was actually indicated.

CONCLUSIONS

Over time, there was increasing adherence to the international guidelines for the selection of patients for surgical resection as evidenced by the significantly increasing proportion of HR^SG06 and HR^FG06 CLPs undergoing surgery. This was associated with a significantly higher proportion of patients with a definitive indication for surgery. These suggested that over time, there was a continuous improvement in our selection of appropriate CLP for surgical treatment.

Characteristics and long-term survival of resected pancreatic cystic neoplasms in Finland. The first nationwide retrospective cohort analysis

BACKGROUND

Pancreatic cystic neoplasms (PCN) are being found increasingly in imaging studies. Even though the characteristics of PCN lesions have been studied extensively in single and multicentre settings, nationwide data is lacking. The aim of this study was to determine the nationwide epidemiologic characteristics and long-term survival of all resected PCNs.

METHODS

For this retrospective cohort analysis, all PCNs operated on in Finland during the period 2000-2008 were identified. Data was collected from all patients: on demographics, comorbidities, symptoms, radiological findings, surgical procedures, complications, histopathological diagnoses and survival. Incomplete pathology reports and any uncertain diagnoses were re-assessed. Survival data was collected after a five-year follow-up period.

RESULTS

The final database included 225 patients with operated PCN. After reviewing the incomplete pathology reports, in 44 cases the original diagnosis was changed, mostly from MCN to IPMN. The most common histopathological diagnoses were IPMN (94/225; 50/225 MD-IPMN, 30/225 MX-IPMN and 14/225 BD-IPMN), SCN (41/225) and MCN (40/225). Overall, 53/225 (23.6%) of the tumours were malignant. Malignancy was detected in MD-IPMN 29/50 (58%), MX-IPMN 10/30 (33.3%), MCN 12/40 (30%), BD-IPMN 2/14 (14.3%) patients. Median 5-year survival for all patients was 77%: 87% in patients without malignancy, 77% with HGD and 27% in patients with a malignant resected PCN.

CONCLUSION

One fourth of the PCNs operated on nationwide were malignant, with a five-year survival of 27%, compared to overall survival of 87% in patients with non-malignant disease and 77% in those with HGD. Detecting - and operating on - a PCN before the malignant transfer remains a great challenge.

Computer-Aided Diagnosis of Pancreas Serous Cystic Neoplasms: A Radiomics Method on Preoperative MDCT Images

OBJECTIVE

Our aim was to propose a preoperative computer-aided diagnosis scheme to differentiate pancreatic serous cystic neoplasms from other pancreatic cystic neoplasms, providing supportive opinions for clinicians and avoiding overtreatment.

MATERIALS AND METHODS

In this retrospective study, 260 patients with pancreatic cystic neoplasm were included. Each patient underwent a multidetector row computed tomography scan and pancreatic resection. In all, 200 patients constituted a cross-validation cohort, and 60 patients formed an independent validation cohort. Demographic information, clinical information, and multidetector row computed tomography images were obtained from Picture Archiving and Communication Systems. The peripheral margin of each neoplasm was manually outlined by experienced radiologists. A radiomics system containing 24 guideline-based features and 385 radiomics high-throughput features was designed. After the feature extraction, least absolute shrinkage selection operator regression was used to select the most important features. A support vector machine classifier with 5-fold cross-validation was applied to build the diagnostic model. The independent validation cohort was used to validate the performance.

RESULTS

Only 31 of 102 serous cystic neoplasm cases in this study were recognized correctly by clinicians before the surgery. Twenty-two features were selected from the radiomics system after 100 bootstrapping repetitions of the least absolute shrinkage selection operator regression. The diagnostic scheme performed accurately and robustly, showing the area under the receiver operating characteristic curve = 0.767, sensitivity = 0.686, and specificity = 0.709. In the independent validation cohort, we acquired similar results with receiver operating characteristic curve = 0.837, sensitivity = 0.667, and specificity = 0.818.

CONCLUSION

The proposed radiomics-based computer-aided diagnosis scheme could increase preoperative diagnostic accuracy and assist clinicians in making accurate management decisions.

Present status and perspectives of endosonography 2017 in gastroenterology

Endoscopic ultrasound has become an essential tool in modern gastroenterology and abdominal surgery. Compared with all other endoscopic methods, it has the most potential for innovation and its future looks bright. Thus, we compiled this summary of established and novel applications of endoscopic ultrasound methods to inform the reader about what is already possible and where future developments will lead in improving patient care further. This review is structured in four parts. The first section reports on developments in diagnostic endoscopic ultrasound, the second looks at semi-invasive endoscopic ultrasound, and the third discusses advances in therapeutic endoscopic ultrasound. An overview on the future prospects of endoscopic ultrasound methods concludes this article.

Clinical Approach to Incidental Pancreatic Cystic Neoplasm in Outpatient Clinics

Cystic lesions of the pancreas are increasingly observed due to increased use of abdominal images. The malignant rate of pancreas cystic lesion varies widely between various types. Identification of malignant or high-risk lesions is important when determining the appropriate course of management. Using these image findings, including cyst size, presence of solid components, and pancreatic duct involvement, the 2012 International Association of Pancreatology (IAP) and the 2015 American Gastroenterological Association (AGA) guidelines provide a rationale in identifying higher risk patients requiring further workups using an endoscopic ultrasound (EUS). EUS with fine needle aspiration and cytology allows confirmation of the cyst type and determines the risk of malignancy. Small cysts with no suspicious features may undergo the regular imaging study for regular surveillance due to low risk for malignancy. In this review, the differences between the 2012 IAP and 2015 AGA guidelines are presented, In addition to possible recommendations for management and surveillance.

Revisions of international consensus Fukuoka guidelines for the management of IPMN of the pancreas

The management of intraductal papillary mucinous neoplasm (IPMN) continues to evolve. In particular, the indications for resection of branch duct IPMN have changed from early resection to more deliberate observation as proposed by the international consensus guidelines of 2006 and 2012. Another guideline proposed by the American Gastroenterological Association in 2015 restricted indications for surgery more stringently and recommended physicians to stop surveillance if no significant change had occurred in a pancreatic cyst after five years of surveillance, or if a patient underwent resection and a non-malignant IPMN was found. Whether or not it is safe to do so, as well as the method and interval of surveillance, has generated substantial debate. Based on a consensus symposium held during the meeting of the International Association of Pancreatology in Sendai, Japan, in 2016, the working group has revised the guidelines regarding prediction of invasive carcinoma and high-grade dysplasia, surveillance, and postoperative follow-up of IPMN. As the working group did not recognize the need for major revisions of the guidelines, we made only minor revisions and added most recent articles where appropriate. The present guidelines include updated information and recommendations based on our current understanding, and highlight issues that remain controversial or where further research is required.

Discrimination of serous cystadenoma from mucinous cystadenoma in the pancreas with contrast-enhanced ultrasonography: a prospective study in 61 patients

Objectives

The preoperative diagnosis between serous cystadenomas (SCAs) and mucinous cystadenomas (MCAs) in pancreas is significant due to their completely different biological behaviors. The purpose of our study was to examine and compare detailed contrast-enhanced ultrasonography (CEUS) images of SCAs and MCAs and to determine whether there are significant findings that can contribute to the discrimination between these two diseases.

Methods

From April 2015 to June 2016, 61 patients (35 patients with SCAs and 26 patients with MCAs) were enrolled in this study. Forty-three cases were confirmed by surgical pathology and 18 by comprehensive clinical diagnoses. All of the CEUS characteristics of these lesions were recorded: size, location, echogenicity, shape, wall characteristics, septa characteristics, and the presence of a honeycomb pattern or nodules. CEUS examinations were performed by two ultrasound physicians.

Results

Location (P=0.003), shape (P=0.000), thickness of the wall (P=0.005), the number of septa (P=0.001), and the honeycomb pattern (P=0.001) were statistically significantly different. A head–neck location, a lobulated shape, an inner regular honeycomb pattern, and a thin wall (<3 mm thick) were significant in diagnosing patients with SCAs. When two of these four findings were combined, we could achieve a sensitivity of 71.4% and a specificity of 80.8% to diagnose SCA; when three of these four findings were combined, the specificity was 100%. A body–tail location, a round/oval shape, 0–2 septa, and a thick wall (≥3 mm thick) were most often detected in patients with MCAs. When two of these four findings were combined, we could achieve a sensitivity of 88.5% and a specificity of 65.7% to diagnose MCA; when three of these four findings were combined, the area under the curve (Az) was highest at 0.832, with a sensitivity of 80.8% and a specificity of 85.7%.

Conclusions

The characteristics of tumor location, shape, thickness of the wall, the number of septa, and the honeycomb pattern by CEUS play an important role in the diagnosis of SCAs and MCAs. A combination of these findings can provide better diagnostic performance in the discrimination of SCAs from MCAs.

Cystic degeneration of neuro endocrine tumor of pancreas and Crohn's disease: true or coincidental association?

Pancreatic endocrine tumors (PETs) or islet cell tumors are rare lesions, the incidence of which is estimated to be less than 1 per 100,000 person-years in the general population. PETs can be divided into functional (exhibit a distinct clinical syndrome due to hormone hypersecretion) and non-functional tumors. The majority of PETs are non-functional. In spite of their rarity, cystic neoplasms of the pancreas are characterized by existing or potential malignancy that cannot be ignored during decisive process with regard to the choice of treatment. The purpose of this workis to find an association with Crohn's disease and cystic degeneration of a neuroendocrine tumor of the pancreas. Crohn's disease may affect extraintestinal organs, including the pancreas. In such cases, It seems certain that many patients diagnosed with Crohn disease (CD) are predisposed to a wider spectrum of cancers. We present a case of pancreatic cyst with no typical features of pseudocyst in the medical interview, with history of Crohn's disease, treated by caudal pancreatectomy. We tried to evaluate the clinical and morphological features of so-called cystic neoplasms associated with inflammatory bowel disease and to define their pathological characteristics.

Current perspectives on pancreatic serous cystic neoplasms: Diagnosis, management and beyond

Pancreatic cystic neoplasms have been increasingly recognized recently. Comprising about 16% of all resected pancreatic cystic neoplasms, serous cystic neoplasms are uncommon benign lesions that are usually asymptomatic and found incidentally. Despite overall low risk of malignancy, these pancreatic cysts still generate anxiety, leading to intensive medical investigations with considerable financial cost to health care systems. This review discusses the general background of serous cystic neoplasms, including epidemiology and clinical characteristics, and provides an updated overview of diagnostic approaches based on clinical features, relevant imaging studies and new findings that are being discovered pertaining to diagnostic evaluation. We also concisely discuss and propose management strategies for better quality of life.

Serous Neoplasms of the Pancreas: A Clinicopathologic Analysis of 193 Cases and Literature Review With New Insights on Macrocystic and Solid Variants and Critical Reappraisal of So-called "Serous Cystadenocarcinoma"

The literature on "variants" and "malignant" counterparts of pancreatic serous cystic neoplasms (SCNs) is highly conflicted. Clinicopathologic characteristics of 193 SCNs were investigated, along with a critical literature review. For the macrocystic (oligocystic) variant, in this largest series, a demographic profile in contrast to current literature was elucidated, with 21% frequency, predominance in female individuals (4:1), body/tail location (1.7×), younger age of patients (mean age, 50 y), and frequent radiologic misdiagnosis as other megacystic neoplasms. Solid SCNs were rare (n=4, 2%) and often misinterpreted radiologically as neuroendocrine tumors. Available fine-needle aspiration in 11 cases was diagnostic in only 1. Radiologic impression was "malignancy" in 5%. Associated secondary tumors were detected in 13% of resections, mostly neuroendocrine. Secondary "infiltration" (direct adhesion/penetration) of spleen, stomach, colon, and/or adjacent nodes was seen in 6 (3%) fairly large SCNs (mean, 11 cm) with no distant metastasis. Three SCNs recurred locally, but completeness of original resection could not be verified. Our only hepatic SCN lacked a concurrent pancreatic tumor. Literature appraisal revealed that there are virtually no deaths that are directly attributable to dissemination/malignant behavior of SCNs, and most cases reported as "malignant" in fact would no longer fulfill the more recent World Health Organization criteria but instead would represent either (1) local adhesion/persistence of tumor, (2) cases with no histologic verification of malignancy, or (3) liver SCNs with benevolent behavior (likely representing multifocality, rather than true metastasis, especially considering there was no fatality related to this and no reported metastases to other remote sites). In conclusion, in contrast to the literature, the clinicopathologic characteristics of solid and macrocystic SCN variants are similar to their microcystic counterpart, although their radiologic diagnosis is challenging. Recurrence/secondary invasion of neighboring organs occurs rarely in larger SCNs but seems innocuous. An SCN should not be classified as "malignant" unless there is clear-cut evidence of histologic malignancy or documented distant metastasis.

Analysis of VEGF/PlGF heterodimer level in pancreatic cyst fluid as a biomarker for serous cystadenoma

INTRODUCTION

Pancreatic cyst fluid (PCF) analysis provides valuable information in the preoperative evaluation of pancreatic cysts. Vascular endothelial growth factors (VEGF) and other proangiogenesis factors such a placental growth factor (PlGF) are promising biomarkers for identifying serous cystadenoma (SCA). VEGF-A has recently been reported as a SCA marker. We sought to assess the value of the VEGF-A/PlGF heterodimer as a potential biomarker of SCA in PCF.

MATERIALS AND METHODS

PCF was analyzed for VEGF/PlGF and 7 additional proangiogenic markers including VEGF-A, VEGF-C, VEGF-D, TEK tyrosine kinase, endothelial (TIE-2), soluble fms-like tyrosine kinase-1 (sFlt-1), PlGF, and basic fibroblast growth factor (bFGF). True-positive or false-negative results were determined by histological confirmation of SCA and false-positive or true-negative results with confirmation of a non-SCA cyst by either cytology or histology, elevated carcinoembryonic antigen ≥192 ng/mL, elevated amylase ≥5000 U/L, or detected KRAS/GNAS mutations.

RESULTS

Forty-eight PCFs were analyzed; 1 was technically inadequate. Of the remaining 47, 3 (6%) contained measurable (>60 pg/mL) concentrations of VEGF/PlGF heterodimer: 1 pseudocyst, 1 cystic adenocarcinoma, and 1 SCA. Of 6 histologically confirmed SCAs, there was only 1 (17%) true positive. Six PCFs were not classifiable due to insufficient data, leaving 41 PCFs for performance calculations (33 true negative, 5 false negative, 1 true positive, and 2 false positive) yielding a sensitivity of 17% and specificity of 94%.

CONCLUSIONS

VEGF/PlGF heterodimer is present in low concentrations in PCF and is an insensitive biomarker for SCA. Additional study is required to determine clinical utility of heterodimeric VEGF/PlGF in combination with other proangiogenic markers.

Management of serous cystic neoplasms of the pancreas

Pancreatic serous cystadenomas are uncommon benign tumours that are often found incidentally on routine imaging examinations. Radiological imaging techniques alone have proven to be suboptimal to fully characterize cystic pancreatic lesions. Endoscopic ultrasound, with the addition of fine-needle aspiration in difficult cases, has showed greater diagnostic accuracy than conventional imaging techniques. The best management strategy of these neoplasms is still debated. Surgery should be limited only to symptomatic and highly selected cases and most of the patients should only be strictly monitored. In the current paper, we provide an updated overview on pancreatic serous cystadenomas, focusing our attention on epidemiology, clinical characteristics and diagnostic evaluation; finally, we also discuss different management strategies and areas for future research.

Computer-Aided Diagnosis for Distinguishing Pancreatic Mucinous Cystic Neoplasms From Serous Oligocystic Adenomas in Spectral CT Images

OBJECTIVE

This preliminary study aims to verify the effectiveness of the additional information provided by spectral computed tomography (CT) with the proposed computer-aided diagnosis (CAD) scheme to differentiate pancreatic serous oligocystic adenomas (SOAs) from mucinous cystic neoplasms of pancreas cystic lesions.

MATERIALS AND METHODS

This study was conducted from January 2010 to October 2013. Twenty-three patients (5 men and 18 women; mean age, 43.96 years old) with SOA and 19 patients (3 men and 16 women; mean age, 41.74 years old) with MCN were included in this retrospective study. Two types of features were collected by dual-energy spectral CT imaging as follows: conventional and additional quantitative spectral CT features. Classification results of the CAD scheme were compared using the conventional features and full feature data set. Important features were selected using support vector machine classification method combined with feature-selection technique. The optimal cutoff values of selected features were determined through receiver-operating characteristic curve analyses.

RESULTS

Combining conventional features with additional spectral CT features improved the overall accuracy from 88.37% to 93.02%. The selected features of the proposed CAD scheme were tumor size, contour, location, and low-energy CT values (43 keV). Iodine-water basis material pair densities in both arterial phase (AP) and portal venous phase (PP) were important factors for differential diagnosis of SOA and MCN. The optimal cutoff values of long axis, short axis, 40 keV monochromatic CT value in AP, iodine (water) density in AP, 43 keV monochromatic CT value in PP, and iodine (water) density in PP were 3.4 mm, 3.1 mm, 35.7 Hu, 0.32533 mg/mL, 39.4 Hu, and 0.348 mg/mL, respectively.

CONCLUSION

The combination of conventional features and additional information provided by dual-energy spectral CT shows a high accuracy in the CAD scheme. The quantitative information of spectral CT may prove useful in the diagnosis and classification of SOAs and MCNs with machine learning algorithms.

Moving beyond morphology: new insights into the characterization and management of cystic pancreatic lesions

The frequency of detection of cystic pancreatic lesions with cross-sectional imaging, particularly with multidetector computed tomography, magnetic resonance (MR) imaging, and MR cholangiopancreatography, is increasing, and many of these cystic pancreatic lesions are being detected incidentally in asymptomatic patients. Because there is considerable overlap in the cross-sectional imaging findings of cystic pancreatic lesions, and because many of these lesions being detected are smaller than 3 cm in diameter and lack any specific cross-sectional imaging features, it has become difficult to make informed decisions about patient management when the precise diagnosis remains uncertain. This article presents the limitations of cross-sectional imaging in patients with cystic pancreatic lesions, details advances in knowledge of the genomic and epigenomic changes that lead to progression of carcinogenesis, outlines the current understanding of the natural history of mucinous cystic lesions, and includes the current use and future potential of novel tumor markers and molecular analysis to characterize cystic pancreatic lesions more precisely. The need to move beyond cross-sectional imaging morphology and toward the use of new techniques to diagnose these lesions accurately is emphasized. An algorithm that uses these techniques is proposed and will hopefully lead to improved patient management.

Ethanol lavage of 14 mucinous cysts of the pancreas: A retrospective study in two tertiary centers

Background:

Mucinous cysts are lesions with malignant potential. Their management is stil difficult. Ethanol lavage under EUS can be used and could be a good alternative treatment. We report a bi-center experience of ethanol lavage in mucinous cysts of the pancreas.

Patients and methods:

A total of 13 patients in 2 tertiary centers (7 men, 6 women, mean age=68.5 years) underwent ethanol lavage for mucinous cysts under endoscopic ultrasound (EUS) from 2001 to 2010. One of the patients had 2 cysts treated during the same procedure. One patient underwent a second procedure of ethanol lavage. Mucinous cyst diagnosis required: (1) EUS showing cystic lesion without nodule and without communication with pancreatic branch duct. Six cysts were located in the isthmus of the pancreas, 3 in the head, 3 in the body, and 2 in the tail. The mean size was 24 mm (11-50); and (2) Intra-cystic ACE level >400 UI/l and/or histologic proof. Diagnosis of mucinous cyst was obtained using ACE levels in 5 cases, histology in 8 cases, and both in 1 case.

Results:

No complication was reported. Complete responses were observed in 11 cases (85%), with no responses in 2 cases (15%). Mean follow-up was 26 months (4-118 months). Contact was lost with 1 patient. No recurrence was noticed in patients with complete responses.

Conclusion:

This study confirms the feasibility and effectiveness of a loco-regional treatment under EUS for pancreatic cysts. The good ratio of response is probably explained by the lack of septa and the small size of the cysts. The follow-up is still short and needs to be increased. Nethertheless loco-regional treatment of pancreatic cysts lesions under EUS should form a part of the management of pancreatic lesions.

Differential diagnosis of pancreatic serous oligocystic adenoma and mucinous cystic neoplasm with spectral CT imaging: initial results

AIM

To investigate the imaging characteristics of pancreatic serous oligocystic adenoma (SOA) and mucinous cystic neoplasms (MCNs) using spectral computed tomography (CT) and to evaluate whether quantitative information derived from spectral imaging can improve the differential diagnosis of these diseases.

MATERIALS AND METHODS

From February 2010 to June 2013, 44 patients (24 SOAs and 20 MCNs) who underwent spectral CT imaging were included in the study. Conventional characteristics and quantitative parameters were compared between the two disease groups. Logistic regression was used for multiparametric analysis. The receiver-operating characteristic curve was used to evaluate the diagnostic performance of single parameter and multiparametric analysis. Two radiologists diagnosed the diseases blinded and independently, without and with the information of the statistical analysis.

RESULTS

Tumour location, contour, size, and monochromatic CT values at 40 keV to 70 keV, iodine concentration, and effective atomic number (effective-Z) in the late arterial phase were the independent factors correlated with category. Multiparametric analysis with logistic regression showed that tumour size, location, and contour were the most effective variations, and obtained an area under the ROC curve (AUC) of 0.934. With the knowledge of statistical analysis, the accuracy of the first reader increased from 70.5% to 86.4%, and the accuracy of the second reader increased from 81.8% to 90.9%.

CONCLUSIONS

Although CT spectral imaging provided additional information and multiparametric analysis obtained better performance than single-parameter analysis in differentiating MCNs from SOAs, multiparametric analysis with the combination of quantitative parameters derived from CT spectral imaging did not improve the diagnostic performance. Tumour size, location, and contour played an important role in differentiating MCNs from SOAs.

Mucinous Cystic Neoplasms of Pancreas

The purpose of this study was to investigate the actual management of mucinous cystic neoplasm (MCN) of the pancreas. A systematic review was performed in December 2009 by consulting PubMed MEDLINE for publications and matching the key words “pancreatic mucinous cystic neoplasm”, “pancreatic mucinous cystic tumor”, “pancreatic mucinous cystic mass”, “pancreatic cyst” and “pancreatic cystic neoplasm” to identify English language articles describing the diagnosis and treatment of the MCN of the pancreas. In total, 16,322 references ranging from January 1969 to December 2009 were analyzed and 77 articles were identified. No articles published before 1996 were selected because MCNs were not previously considered to be a completely autonomous disease. Definition, epidemiology, anatomopathological findings, clinical presentation, preoperative evaluation, treatment and prognosis were reviewed. MCNs are pancreatic mucin-producing cysts with a distinctive ovarian-type stroma localized in the body-tail of the gland and occurring in middle-aged females. The majority of MCNs are slow growing and asymptomatic. The prevalence of invasive carcinoma varies between 6% and 55%. Preoperative diagnosis depends on a combination of clinical features, tumor markers, computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound with cyst fluid analysis and positron emission tomography-CT. Surgery is indicated for all MCNs.

Are the Sendai and Fukuoka consensus guidelines for cystic mucinous neoplasms of the pancreas useful in the initial triage of all suspected pancreatic cystic neoplasms? A single-institution experience with 317 surgically-treated patients

BACKGROUND

The Sendai Consensus Guidelines (SCG) were formulated in 2006 and updated in Fukuoka in 2012 (FCG) to guide management of cystic mucinous neoplasms of the pancreas. This study aims to evaluate the clinical utility of the SCG and FCG in the initial triage of all suspected pancreatic cystic neoplasms.

STUDY DESIGN

Overall, 317 surgically-treated patients with a suspected pancreatic cystic neoplasm were classified according to the SCG as high risk (HR(SCG)) and low risk (LR(SCG)), and according to the FCG as high risk (HR(FCG)), worrisome (W(FCG)), and low risk (LR(FCG)). Cystic lesions of the pancreas (CLP) were classified as potentially malignant/malignant or benign according to the final pathology.

RESULTS

The presence of symptoms, proximal lesions with obstructive jaundice, elevated serum carcinoembryonic antigen/carbohydrate antigen 19-9 (CEA/CA 19-9), size ≥3 cm, presence of solid component, main pancreatic duct dilatation, thickened enhancing walls, and change in ductal caliber with distal atrophy were predictive of a potentially malignant/malignant CLP on univariate analyses. The positive predictive value (PPV) and negative predictive value (NPV) of HR(SCG) and HR(ICG2012) for a potentially malignant/malignant lesion was 67 and 88 %, and 88 and 92.5 %, respectively. There were no malignant lesions in both LR groups but some potentially malignant lesions such as cystic pancreatic neuroendocrine neoplasms with uncertain behavior were classified as LR.

CONCLUSION

The updated FCG was superior to the SCG for the initial triage of all suspected pancreatic cystic neoplasms. CLP in the LR(FCG) group can be safely managed conservatively, and those in the HR(FCG) group should undergo resection.

A review of pancreatic cyst fluid analysis in the differential diagnosis of pancreatic cyst lesions

Diagnosis and management of pancreatic cyst lesions is challenging as there is currently no investigation that offers both high diagnostic sensitivity and high specificity for the identification of potentially malignant lesions. Accurate classification of these lesions is vital in order to avoid unnecessary treatment of benign lesions and missed opportunities for early treatment of lesions that are malignant/pre-malignant. Pancreatic cyst fluid analysis has an important role in diagnosis, although all currently available investigations based on fluid analysis have significant limitations. Cytological analysis can reveal features that are specific for a certain class of cyst, but offers limited sensitivity in detecting malignant/pre-malignant cysts. Measurement of tumour markers, particularly carcinoembryonic antigen can also be informative. Concentrations of cyst fluid carcinoembryonic antigen tend to be higher in malignant/pre-malignant cysts, although there is a wide overlap between the various classes of cyst. A number of studies have suggested that diagnostic carcinoembryonic antigen cut-offs can be chosen that provide a high degree of specificity but limited sensitivity. Studies of the analytical validity of tumour marker assays in pancreatic cyst fluid analysis have highlighted discrepancies in some fluid specimens, which require further investigation. DNA analysis also has a role. In particular, K-Ras-2 mutational analysis appears to provide high specificity for detection of malignant/pre-malignant lesions. A number of diagnostic algorithms have been published, integrating use of available investigations in order to achieve the optimum discrimination of benign and potentially malignant cysts. Research into new biochemical markers and optimal use of available pancreatic cyst fluid analyses is ongoing.

Microcystic serous cystadenoma of the pancreas with subtotal cystic degeneration: another neoplastic mimic of pancreatic pseudocyst

BACKGROUND

Pancreatic serous cystadenomas are benign cystic neoplasms. Extensive degeneration mimicking a pancreatic pseudocyst has been described in several types of pancreatic neoplasms but has not been documented in serous cystadenomas. We report subtotal cystic degeneration of microcystic serous cystadenomas (MSCA) that produces radiographic, gross, and microscopic overlap with pancreatic pseudocyst.

MATERIALS AND METHODS

Resected MSCA with degenerative change were identified from the pathology archives of Memorial Sloan-Kettering Cancer Center and Johns Hopkins Hospital. The clinical, radiographic, gross, and microscopic findings were reviewed.

RESULTS

Eight MSCAs with subtotal cystic degeneration were retrieved from among 397 resected serous cystadenomas (2.0%). There were 2 men and 6 women (mean age, 52 y). Available radiographic studies showed classic features of MSCA in 2 of 4 cases. Four cysts were unilocular, and 4 were multilocular. Gross features of MSCA were noted focally in the multilocular cases but were not evident in the unilocular examples. The predominant histologic features were those of pancreatic pseudocyst, including a fibrotic cyst wall lacking epithelium and instead composed of myofibroblastic proliferation, hemorrhage, and inflammation. Residual foci of MSCA were embedded in fibrosis, comprising 5% to 60% of the tumor volume.

CONCLUSIONS

Most pancreatic serous cystadenomas display characteristic morphology, including a glycogen-rich epithelial lining and prominent subepithelial capillaries; however, extensive degenerative macrocystic change can obscure these classic features. This phenomenon is to be distinguished from macrocystic serous cystadenoma, in which thin-walled macrocystic spaces are epithelium lined. Thus, serous cystadenoma should be included in the differential diagnosis of pancreatic masses with extensive degenerative cystic change.

International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas

The international consensus guidelines for management of intraductal papillary mucinous neoplasm and mucinous cystic neoplasm of the pancreas established in 2006 have increased awareness and improved the management of these entities. During the subsequent 5 years, a considerable amount of information has been added to the literature. Based on a consensus symposium held during the 14th meeting of the International Association of Pancreatology in Fukuoka, Japan, in 2010, the working group has generated new guidelines. Since the levels of evidence for all items addressed in these guidelines are low, being 4 or 5, we still have to designate them "consensus", rather than "evidence-based", guidelines. To simplify the entire guidelines, we have adopted a statement format that differs from the 2006 guidelines, although the headings are similar to the previous guidelines, i.e., classification, investigation, indications for and methods of resection and other treatments, histological aspects, and methods of follow-up. The present guidelines include recent information and recommendations based on our current understanding, and highlight issues that remain controversial and areas where further research is required.

Intraductal papillary mucinous neoplasms: does a family history of pancreatic cancer matter?

BACKGROUND/OBJECTIVES

The purpose of this study is to compare surgically resected intraductal papillary mucinous neoplasms (IPMNs) in patients with and without a family history of pancreatic cancer to gain insight into differences that may suggest the need for differential management.

METHODS

A retrospective review of patients who underwent resection of an IPMN at the Massachusetts General Hospital (1990-2011) was conducted. Three hundred and twenty-four patients of whom 45 (13.9%) had a family history of pancreatic cancer were identified. Patients with (PFH) and without (NFH) a family history of pancreatic cancer were compared.

RESULTS

There were no differences in demographic characteristics between groups. Extra-pancreatic malignancies diagnosed prior to the IPMN were more common in those with a PFH (35.6% vs 20.1%, p = 0.03). There were no differences in IPMN characteristics between groups including no difference in the presence of invasive disease (p = 0.55). Concurrent pancreatic ductal adenocarcinomas were more common in those with a PFH (11.1% vs 2.9%, p = 0.02). The survival in the PFH group was marginally lower than the NFH group, a difference found to be attributable to the higher prevalence of extra-pancreatic malignancies.

CONCLUSION

Characteristics of surgically resected IPMNs are not different between patients with and without a family history of pancreatic cancer. Most importantly, the incidence of invasive disease is not different, suggesting that these lesions may not be more aggressive when they occur in the presence of a family history of pancreatic cancer.

Pancreatic serous cystadenoma with compression of the main pancreatic duct: an unusual entity

Serous cystadenoma is a common benign neoplasm that can be managed without surgery in asymptomatic patients provided that the diagnosis is certain. We describe a patient, whose pancreatic cyst exhibited a radiological appearance distinct from that of typical serous cystadenoma, resulting in diagnostic difficulties. CT and MRI showed a 10 cm-polycystic tumor with upstream dilatation of the main pancreatic duct (MPD), suggestive of intraductal papillary mucinous tumor (IPMT). Ultrasonographic aspect and EUS-guided fine-needle aspiration gave arguments for serous cystadenoma. ERCP showed a communication between cysts and the dilated MPD, compatible with IPMT. The patient underwent left pancreatectomy with splenectomy. Pathological examination concluded in a serous cystadenoma, with only a ductal obstruction causing proximal dilatation.

MRI features of serous oligocystic adenoma of the pancreas: differentiation from mucinous cystic neoplasm of the pancreas

OBJECTIVES

The purpose of this study was to describe the MRI features of the benign pancreatic neoplasm serous oligocystic adenoma (SOA) that differ from those of mucinous cystic neoplasm (MCN), a neoplasm with the potential for malignant degeneration.

METHODS

Seven patients with SOA (seven women; mean age 36.6 years) and eight patients with MCN (eight women: mean age 39.9 years) were included. Several imaging features were reviewed: mass size, location, shape, wall thickness, cyst configuration (Type I, unilocular; Type II, multiple clustered cyst; Type III, cyst with internal septation) and signal intensity of the lesion with heterogeneity.

RESULTS

SOA lesions were smaller (3.4 cm) than those of MCN (9.3 cm) (p=0.023). The commonest lesion shape was lobulated (85.7%) for SOA, but oval (50.0%) or lobulated (37.5%) for MCN (p=0.015). The most common cyst configuration was Type II (85.7%) for SOA and Type III (75.0%) for MCN (p=0.008). Heterogeneity of each locule in T(1) weighted images was visible in all cases of MCN, but in no case for SOA (p=0.004).

CONCLUSION

SOA could be differentiated from MCN by identifying the imaging features of lobulated contour with multiple clustered cyst configurations and homogeneity of each locule in T(1) weighted MR images.

Comparative immunohistochemical study of the stroma of serous and mucinous cystic neoplasms: possible histopathogenetic relationship of the 2 entities

OBJECTIVES

Serous and mucinous cystic neoplasms (SCNs/MCNs) are the most common true cystic neoplasms of the pancreas and occur more frequently in women. The aim of this study was to characterize the stroma of SCNs to compare its phenotype with that of MCNs.

METHODS

A total of 12 SCNs and 5 MCNs were analyzed immunohistochemically using the following antisera: progesterone receptor (PR), estrogen receptor (ER), inhibin, CD10, and vimentin. Normal pancreatic tissue (17 cases) and ductal adenocarcinomas of the pancreas (3 cases) were used as controls.

RESULTS

Eight of 12 patients with SCNs and all 5 patients with MCNs were women. For SCNs, the stroma was sclerotic and paucicellular and showed focal moderate to strong reactivity for PR. Estrogen receptor, CD10, and inhibin were virtually negative. For MCNs, the stroma was more cellular and ovarianlike and showed a larger number of PR-positive cells with focal expression of ER and inhibin. Vimentin was expressed in all stromal cells in both groups.

CONCLUSIONS

Both SCNs and MCNs contain PR-positive stromal cells. In view of the aforementioned clinical and immunophenotypical similarities, we suggest that in SCNs and MCNs, the stromal framework is similar in origin and/or differentiation.

Serous cystic neoplasms of the whole pancreas in a patient with von Hippel-Lindau disease

We describe here a case of von Hippel-Lindau (VHL) disease with a serous cystic neoplasm of the whole pancreas. The patient was a 35-year-old woman suffering from a palpable abdominal tumor. She had a history of hemangioblastomas of the cerebellum. CT revealed large solid tumors in the pancreatic head and body, and multiple cystic lesions in the whole pancreas as well as a right renal tumor. When endoscopic retrograde cholangiopancreatography (ERCP) was performed, bleeding from the duodenal papilla was detected. Since she had some distinguishing clinical features, the diagnosis of VHL disease was made. The preoperative diagnosis of the pancreatic lesion was serous cystic neoplasms with hemosuccus pancreaticus and total pancreatectomy was performed. Histological examination of the specimen revealed serous cystic neoplasms which occupied the entire pancreas. VHL cases operated on for serous cystic neoplasms of the entire pancreas are very rare.

Management of mucinous cystic neoplasms of the pancreas

The purpose of this study was to investigate the actual management of mucinous cystic neoplasm (MCN) of the pancreas. A systematic review was performed in December 2009 by consulting PubMed MEDLINE for publications and matching the key words “pancreatic mucinous cystic neoplasm”, “pancreatic mucinous cystic tumour”, “pancreatic mucinous cystic mass”, “pancreatic cyst”, and “pancreatic cystic neoplasm” to identify English language articles describing the diagnosis and treatment of the mucinous cystic neoplasm of the pancreas. In total, 16 322 references ranging from January 1969 to December 2009 were analysed and 77 articles were identified. No articles published before 1996 were selected because MCNs were not previously considered to be a completely autonomous disease. Definition, epidemiology, anatomopathological findings, clinical presentation, preoperative evaluation, treatment and prognosis were reviewed. MCNs are pancreatic mucin-producing cysts with a distinctive ovarian-type stroma localized in the body-tail of the gland and occurring in middle-aged females. The majority of MCNs are slow growing and asymptomatic. The prevalence of invasive carcinoma varies between 6% and 55%. Preoperative diagnosis depends on a combination of clinical features, tumor markers, computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound with cyst fluid analysis, and positron emission tomography-CT. Surgery is indicated for all MCNs.

Imaging of benign and malignant cystic pancreatic lesions and a strategy for follow up

Cystic lesions in a variety of organs are being increasingly recognized as an incidental finding on cross-sectional imaging. These lesions can be benign, premalignant or malignant. When these cystic lesions are small it can be difficult to characterize them radiologically. However, with appropriate clinical history and knowledge of typical imaging features of cystic pancreatic lesions this can enable accurate diagnosis and thus guide appropriate treatment. In this review, we provide an overview of the most common types of cystic lesions and their appearance on computer tomography, magnetic resonance imaging and ultrasound. We will also discuss the follow up and management strategies of these cystic lesions.

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.

CT imaging spectrum of pancreatic serous tumors: based on new pathologic classification

PURPOSE

The aim of this study is to retrospectively analyze the variety of CT findings based on new pathologic classification.

MATERIALS AND METHODS

During a 10-year period, 59 histopathologically proven pancreatic SCTs and 13 SCTs confirmed with typical image findings and strict clinical criteria were enlisted. Two radiologists analyzed CT images for the following items in consensus: location, size, outer margin, tumor shape, the presence of mural nodule, communication with main pancreatic duct (MPD), the presence and extent of MPD dilatation, calcification, central scar, and attenuation on pre- and post-contrast CT images. In addition, typicality of CT findings was determined. A typical finding was defined as a honeycomb appearance without or with oligocystic portion. In the cases with atypical features, the type of atypical features and differential diagnosis were recorded. For the shape of the tumor, tumors were categorized into the following groups: honeycomb without or with oligocystic, pleomorphic, purely oligolocular, unilocular cystic, hypovascular solid, hypervascular solid without or with oligocystic portion, and fingerlike cystic patterns.

RESULTS

28 SCTs (38.9%) presented a honeycomb appearance with (n=14) or without oligocystic portion (n=14) and were classified as typical cases. The remaining 44 atypical cases (61.1%) presented the following: purely oligolocular pattern in 18; hypervascular solid without (n=7) or with oligocystic portion (n=2) in 9; pleomorphic in 8; unilocular cystic in 7; and fingerlike cystic pattern in 2. Most of the lesions manifesting as hypervascular solid lesions were confused with true solid hypervascular tumors such as neuroendocrine tumors or solid pseudopapillary tumors. For most of the remaining atypical lesions, mucinous cystic neoplasm or branch duct type IPMN were included as a differential diagnosis.

CONCLUSION

Serous cystic tumors of the pancreas can have variable CT appearances ranging from compactly solid hypervascular to clearly unilocular cystic, which reflect a varied macroscopic morphology. Only 38.9% of the SCTs show traditional typical CT features whereas a considerable proportion (61.1%) of SCTs showed atypical appearances, providing diagnostic challenges to radiologists.

Survival in cystic neoplasms of the pancreas

BACKGROUND

The natural history of pancreatic cystic neoplasms remains poorly understood despite growing evidence on the subject. Pancreatic cysts display a wide spectrum of pathological phenotypes, each associated with a different prognostic implication. Many pancreatic cysts are of undetermined malignant potential at presentation and remain so until surgically resected. While the survival rates of patients with malignant cysts are known to be poor, survival rates in patients with undetermined pancreatic cysts are unknown.

OBJECTIVE

To identify the factors associated with survival in a group of patients diagnosed with a pancreatic cyst(s).

METHODS

The present study was a retrospective multicentre review of pancreatic cystic neoplasms. All patients with a diagnosis of a neoplastic pancreatic cyst from 1994 to 2003 were identified at five different institutions in Edmonton, Alberta. The data collected included patient age, sex, imaging modality, cyst location, cyst size, number of cysts, comorbid illnesses, history of upper abdominal surgery, previous cancer, previous or concurrent metastases, symptoms (pain, upper gastrointestinal bleeding, signs of biliary obstruction, nausea/vomiting), remarkable radiological features, elevated amylase or lipase, type of pancreatic surgery, final pathology (benign or malignant) and overall survival. Survival models were used to assess whether any covariates were predictors of the survival time. Patient data were plotted using the Kaplan-Meier method. The resulting plot was used to calculate survival in the cohort.

RESULTS

In total, 64 patients were identified as having neoplastic pancreatic cysts from 1994 to 2003 at the five institutions. The median overall patient survival time was 86 months. The median age at diagnosis for the patient population was 73 years, with 40 patients being women. Univariate analysis revealed that the risk of death was associated with patient age, sex and history of major comorbid illness. Multivariate models identified increased patient age and male sex as the factors that correlated most strongly with decreased overall survival.

CONCLUSION

Overall survival in patients with neoplastic pancreatic cysts is determined by patient factors (ie, age and sex) rather than factors descriptive of the cyst such as size and morphology. No conclusions could be made regarding the relationship between cyst pathology and patient survival.

Predictive value of multi-detector computed tomography for accurate diagnosis of serous cystadenoma: Radiologic-pathologic correlation

AIM: To identify multi-detector computed tomography (MDCT) features most predictive of serous cystadenomas (SCAs), correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance.

METHODS: The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size (≤ 3 cm or ≥ 3 cm) and scanning protocols (dedicated vs routine).

RESULTS: 28/164 cysts (mean size, 39 mm; range, 8-92 mm) were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance (22/28, 78.6%), surface lobulations (25/28, 89.3%) and central scar (9/28, 32.4%). Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA (P = 0.0001). The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and lobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions > 3 cm (P = 0.02) and for MDCT scans performed using thin collimation (1.25-2.5 mm) compared to routine 5 mm collimation exams (P > 0.05).

CONCLUSION: Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface lobulations offers accuracy comparable to central scar with higher sensitivity.

Intraoperative ultrasound of the pancreas

Intraoperative ultrasound provides spatial resolution of the pancreas superior to computed tomography, magnetic resonance imaging, and transabdominal sonography. This pictorial essay will review common benign and malignant pancreatic processes including the following: pancreatic ductal adenocarcinoma, pancreatitis, endocrine tumors, mucinous cystic neoplasm, intraductal papillary mucinous neoplasm, serous cystadenoma, and solid pseudopapillary tumor. The use of intraoperative ultrasound in specific surgical situations will be discussed, which include the following: (1) identification of insulinoma(s) which are not detectable preoperatively, (2) identification of the pancreatic duct to determine dissection planes for chronic pancreatitis surgery (eg, Puestow procedure) and for tumor resection, and (3) staging purposes for malignant disease.

Cystic Neoplasms of the Pancreas: Current Diagnostic Modalities and Management

Cystic neoplasm of the pancreas is a relatively uncommon condition covering a wide spectrum of pathology. The increasing incidence as a result of routine imaging tests in asymptomatic patients presents a diagnostic and therapeutic problem to the clinician. This paper discusses the role of the various investigative modalities in the management of cystic neoplasia of the pancreas. Key words: Frantz tumour, Intraductal papillary mucinous neoplasm, Mucinous cystadenoma, Mucinous cystadenocarcinoma, Mucinous neoplasm of the pancreas, Solid pseudopapillary neoplasm

Three cases of serous oligocystic adenomas of the pancreas; evaluation of cyst wall thickness for preoperative differentiation from mucinous cystic neoplasms

BACKGROUND

Serous oligocystic adenoma (SOA), a rare pancreatic neoplasm, is generally a benign lesion without the necessity of surgery. Preoperatively, it is difficult to discriminate SOA from mucinous cystic neoplasm (MCN), which essentially needs surgical treatment. The purpose of this study was to evaluate the cyst wall thickness of SOAs and MCNs for preoperative differential diagnosis.

METHODS

We experienced three cases of SOAs with typical histopathological features. The cyst wall thickness of the SOAs was evaluated in the area protruding out of the pancreas and was compared with that of 13 MCNs histopathologically. The same evaluation and comparison were conducted on preoperative computed tomography (CT) images retrospectively.

RESULTS

The SOAs had a uniformly thin cyst wall measuring less than 1 mm. In contrast, the largest area of a cyst wall in MCNs ranged from 2.5 to 10.0 mm. On CT images, all but one of the MCNs showed a detectable cyst wall, while the cyst walls were hardly recognizable in two of the three SOAs.

CONCLUSIONS

For preoperative differentiation between SOAs and MCNs, the evaluation of cyst wall thickness may be an important tool and may contribute to the decision of treatment strategy.

[Serous microcystic adenoma of the head of the pancreas causing an obstructive jaundice]

BACKGROUND

Serous microcystic adenoma is a rare benign tumor of the exocrine pancreas originating from the ductal system and composed of a large number of small cysts covered by cuboid cells, filled with clear serous fluid and separated with fibrocolagenous stroma. Most frequently it appears in women in 7th and 8th decades, in the distal pancreas. It shows a very low malignant potential. In 2/3 of patients symptoms are uncharacteristic and in 1/3 they are absent When localised within the head of the pancreas it rarely causes an obstructive jaundice.

CASE REPORT

We presented a 61-year-old female patient who for months had had mild and nonspecific abdominal symptoms developing to progressive obstructive jaundice. At surgery we revealed a rather large policystic mass of the head of the pancreas causing not only obstructive jaundice but also a venous stasis by compression and dislocation of the portomesenteric vein. The tumor was removed with pylorus preserving cephalic duodenopancreatectomy (Whipple's procedure modified by Longmire-Traverso). Histology confirmed serous microcystic adenoma of the pancreas. The postoperative recovery was uneventful and preoperative symptoms disappeared.

CONCLUSION

Although very rare, serous microcystic adenoma might appear within the head of the pancreas and has to be taken into consideration in differential diagnosis of cystic lesions of the head of the pancreas. Very rarely the tumour might cause obstructive jaundice. Surgical resection, which might be demanding, leads to complete recovery.

[Cystic tumors of the pancreas]

Cystic lesions of the pancreas encompass a broad spectrum of benign, premalignant, and malignant tumors which are primarily cystic or result from cystic necroses of solid neoplasms. Because of the wide use of cross-sectional imaging techniques they are increasingly being identified in asymptomatic patients as well as in patients presenting with abdominal pain, jaundice or pancreatitis. Among these lesions, intraductal papillary mucinous neoplasms, serous cystic neoplasms and mucinous cystic neoplasms represent the majority of cases. With increasing experience with these tumors, a refinement of our understanding of their morphology and of their natural course has emerged. It is important to be familiar with the CT and MR imaging features of these lesions to differentiate these tumors and to orient the diagnosis towards benign or malignant forms. Because characterization of cystic tumors of the pancreas can sometimes be difficult due to overlapping imaging features, additional criteria such as clinical symptoms, localization, age and gender have to be taken into account. If appropriately treated, these tumors can usually be cured by resection and the decreasing risk of pancreatic surgery has led to an increasing number of resections of pancreatic tumors. The management of cystic tumors of the pancreas has not yet been standardized and the correct evaluation and subsequent management of the disease in asymptomatic patients have not been fully defined.

Cystic lesions of the pancreas. A diagnostic and management dilemma

BACKGROUND/AIMS

Due to enhanced imaging modalities, pancreatic cysts are being increasingly detected, often as an incidental finding. They comprise a wide range of differing underlying pathologies from completely benign through premalignant to frankly malignant. The exact diagnostic and management pathway of these cysts remains problematic and this review attempts to provide an overview of the pathology underlying pancreatic cystic lesions and suggests appropriate methods of management.

METHODS

A search was undertaken with a Pubmed database to identify all English articles using the keywords 'pancreatic cysts', 'serous cystadenoma', 'intraductal papillary mucinous tumour', 'pseudocysts', 'mucinous cystic neoplasm' and 'solid pseudopapillary tumour'.

RESULTS

The mainstay of assessment of pancreatic cysts is cross-sectional imaging incorporating CT and MRI. Fine-needle aspiration (FNA) (often with endoscopic ultrasound) may provide valuable additional information but can lack sensitivity. Symptomatic cysts, increasing age and multilocular cysts (with a solid component and thick walls) are predictors of malignancy. A raised cyst aspirate CEA, CA 19-9 and mucin content (including abnormal cytology), if present, can accurately distinguish premalignant and malignant cysts from benign ones.

CONCLUSION

In summary, all patients with pancreatic cystic lesions, whether asymptomatic or symptomatic, must be thoroughly investigated to ascertain the underlying nature of the cyst. Small asymptomatic cysts (<3 cm) with no suspicious features on imaging or FNA may be safely followed up. Follow-up should continue for at least 4 years, with a repeat FNA if needed. An algorithm for the management of pancreatic cystic tumours is also suggested. and IAP.

Diagnosis and management of relapsing pancreatitis associated with cystic neoplasms of the pancreas

One of the most important causes of relapsing pancreatitis is a cystic neoplasm of the pancreas. These low grade malignancies may cause pancreatitis by obstructing or communicating with a pancreatic duct. Patients with relapsing pancreatitis and a focal fluid fluid collection should be investigated for the possibility of a mucinous cystic neoplasm. Cross sectional imaging can provide a diagnosis with the imaging findings of a low attenuation cystic lesion containing mural calcification (CT scanning) or a lobular T2 enhancing lesion (MRCP). Endoscopic ultrasound can provide more detailed imaging with the ability to guide fine needle aspiration of the cyst fluid. Cyst fluid analysis can provide a diagnosis of a mucinous cystic lesion with the combination of cytology (mucinous epithelium), elevated carcinoembryonic antigen (CEA), and the presence of DNA mutations. Management of these patients consists of surgical resection and monitoring in patients not able to withstand surgery.