Imaging diagnosis of cystic pancreatic lesions: pseudocyst versus nonpseudocyst

Mediastinal extension of pancreatic pseudocysts causing portal hypertension

Pancreatic pseudocysts are fluid-filled masses with a pseudo-capsule that appear following a pancreatic injury. Pseudocysts are the most frequent cystic lesions of the pancreas, representing about 85% of all pancreatic cysts. The possible complications of pancreatic pseudocysts include infections, hemorrhage, intestinal stenosis or obstruction, and rupture into nearby organs or the peritoneal/retroperitoneal cavity. However, mediastinal extension of pancreatic pseudocysts with portal hypertension is rare. We present a case of an 18-year-old male with a history of weight loss over a 10-month period, presenting with an abdominal lump, hemoptysis, abdominal pain, and dyspnea. He was diagnosed with large pancreatic pseudocysts that extended into the mediastinum by ultrasonography (US) and contrast-enhanced computed tomography (CT) examination. Portal hypertension occurs as a result of portal vein compression. A histopathological examination proved conclusive of pancreatic pseudocysts. The patient was treated with surgery, where the cyst was drained.

Pancreatic Cystic Lesions: Imaging Techniques and Diagnostic Features

The detection of incidental pancreatic cystic lesions has increased over time. It is crucial to separate benign from potentially malignant or malignant lesions to guide management and reduce morbidity and mortality. The key imaging features used to fully characterize cystic lesions are optimally assessed by contrast-enhanced magnetic resonance imaging/magnetic resonance cholangiopancreatography, with pancreas protocol computed tomography offering a complementary role. While some imaging features have high specificity for a particular diagnosis, overlapping imaging features between diagnoses may require further investigation with follow-up diagnostic imaging or tissue sampling.

Integrating Molecular Analysis into the Pathologic Evaluation of Pancreatic Cysts

The development of cross-sectional imaging techniques has enhanced the detection of pancreatic cystic lesions (PCLs). PCLs are found in approximately 2% of the general population, often as incidentally detected lesions on computed tomography or MRI during the evaluation of other medical conditions. Broadly, PCLs are classified as mucinous or nonmucinous. Mucinous PCLs include mucinous cystic neoplasms and intraductal papillary mucinous neoplasms. Nonmucinous PCLs include pseudocysts, serous cystadenomas, solid pseudopapillary neoplasms, and cystic pancreatic neuroendocrine tumors, as well as cystic acinar cell carcinoma, cystic degeneration of pancreatic ductal adenocarcinoma, lymphoepithelial cyst, and others.

Nanomedicine for overcoming therapeutic and diagnostic challenges associated with pancreatic cancer

Pancreatic cancer is the second leading cause of cancer-related death in the USA. The 5-year survival rate for pancreatic cancer is as low as 10%, making it one of the most deadly cancers. This dismal prognosis is caused, in part, by the lack of early detection and screening options, leading to late-stage detection of the disease, at a point at which chemotherapy is no longer effective. However, nanoparticle (NP) drug delivery systems have increased the efficacy of chemotherapeutics by improving the targeting ability of drugs to the tumor site, while also decreasing the risk of local and systemic toxicity. Such efforts can contribute to the development of early diagnosis and routine screening tests, which will drastically improve the survival rates and prognosis of patients with pancreatic cancer.

Mediastinal Extension of a Pancreatic Pseudocyst: A Rare Intrathoracic Complication of Pancreatitis

Pancreatic pseudocysts are a common complication of pancreatitis. However, mediastinal extension of a pseudocyst is rare and often presents with atypical symptoms. We present a case of mediastinal extension of a pancreatic pseudocyst in a 56-year-old woman with a history of alcohol-related chronic pancreatitis, who presented with acute on chronic epigastric abdominal pain and atypical chest pain. Serum lipase was elevated, and imaging by contrast-enhanced computed tomography (CT) demonstrated a paraesophageal fluid collection. This collection was continuous with a peripancreatic pseudocyst and extended into the posterior mediastinum via the esophageal hiatus. Mediastinal extension of a pancreatic pseudocyst was confirmed by magnetic resonance imaging (MRI). The patient was managed conservatively in the hospital with parenteral nutrition therapy, pain control, and close imaging observation. The patient was discharged home to continue conservative management and close imaging follow-up. An initial follow-up CT examination 8 weeks after discharge revealed interval decrease in the posterior mediastinal collection but also interval development of loculated left pleural and pericardial effusions.

Focal Pancreatic Lesions: Role of Contrast-Enhanced Ultrasonography

The introduction of contrast-enhanced ultrasonography (CEUS) has led to a significant improvement in the diagnostic accuracy of ultrasound in the characterization of a pancreatic mass. CEUS, by using a blood pool contrast agent, can provide dynamic information concerning macro- and micro-circulation of focal lesions and of normal parenchyma, without the use of ionizing radiation. On the basis of personal experience and literature data, the purpose of this article is to describe and discuss CEUS imaging findings of the main solid and cystic pancreatic lesions with varying prevalence.

Pancreatic pseudocyst: Dilemma of its recent management (Review)

Advances in radiological techniques have led to an increase in the number of diagnoses of pancreatic pseudocyst, which is the most common pancreatic cyst lesion disease, accounting for two-thirds of all pancreatic cyst lesions. Historically, the management of pancreatic pseudocyst has been achieved through the use of conservative treatments and surgery; however, due to the complications and recurrence rate associated with these techniques, the management of pancreatic pseudocyst is challenging. Surgeons and gastroenterologists have attempted to determine the optimal management technique to treat pancreatic pseudocyst to reduce complications and the recurrence rate. From these investigations, percutaneous catheter, surgical and endoscopic drainage with ultrasonography guidance have become promising management techniques. The present review aimed to summarize the diagnostic and therapeutic methods used for the management of pancreatic pseudocyst and to compare percutaneous catheter, surgical and endoscopic drainage.

Differentiating benign from malignant pancreatic cysts on computed tomography

•

CT can distinguish between benign and premalignant or malignant pancreatic cysts.

•

Solid component and septation were the only CT features that could differentiate benign from malignant cysts.

•

Cyst wall enhancements on CT were more commonly observed in premalignant or malignant cysts than in benign cysts.

•

CT is a necessary diagnostic modality to preoperatively detect and characterize pancreatic lesions.

Purpose

It is important to identify features on computed tomography (CT) that can distinguish between benign and premalignant or malignant pancreatic cysts to avoid unnecessary surgeries. This study investigated the preoperative diagnostic evaluation of cystic pancreatic lesions to determine how advanced imaging and clinical factors should guide management.

Methods

In total, 53 patients with 27 benign and 26 premalignant or malignant cysts were enrolled. CT features of the cysts were compared using univariate and multivariate analyses.

Results

On univariate analysis, a solid component (p < 0.01), septation (p < 0.01), location (p < 0.01), border (p < 0.01), wall enhancement (p = 0.01), lesion margins (p < 0.01), pancreatic atrophy (p = 0.04), and a cystic wall (p < 0.01) were all significantly different between benign and premalignant or malignant cysts. On multivariate analysis, only a solid component (p < 0.01) and septation (p < 0.01) were significant.

Conclusion

A thin cystic wall, uniform homogeneity, a clear border, the presence of septation, pancreatic atrophy, and the absence of both wall enhancements and solid components were more frequently seen in benign cysts. A thick wall, lack of homogeneity, the presence of wall enhancements and solid components, absence of septation, only a small degree of pancreatic atrophy, and unclear borders were more frequent among premalignant or malignant cysts. The only CT features to differentiate benign from premalignant or malignant cysts were a solid component and septation.

The Lesser Sac and Foramen of Winslow: Anatomy, Embryology, and CT Appearance of Pathologic Processes

OBJECTIVE. This article reviews the embryologic development, relevant anatomy, and imaging features, on CT, of pathologic processes involving the lesser sac and foramen of Winslow. CONCLUSION. The lesser peritoneal sac is an intricate anatomic region involved in many disease processes. It is a significant conduit for the spread of disease within the peritoneal cavity. The spectrum of pathologic processes pertaining to the lesser sac can be classified on the basis of the type of involvement, such as a fluid collection (e.g., transudate, exudate, bile, and blood), a mass (e.g., neoplastic or nonneoplastic conditions and lymphadenopathy), or an internal hernia into the lesser sac.

Preoperative Clinical and Computed Tomography (CT)-Based Nomogram to Predict Oncologic Outcomes in Patients with Pancreatic Head Cancer Resected with Curative Intent: A Retrospective Study

Background: Currently, proposed nomograms are mainly based on post-operative histopathology. The purpose of this study was to identify preoperative computed tomography (CT) and clinical information that allow prediction of disease-free (DFS) and overall survival (OS) of patients surgically treated for pancreatic head cancer. Methods: A total of 136 patients who underwent curative-intent surgery were retrospectively reviewed. Based on results from multivariate Cox regression analysis, a prediction model was constructed with preoperative CT features and clinical information. Overall performance of the nomogram was calculated by Harrell’s C-index. Results: Symptoms at diagnosis, preoperative serum CA 19-9 ≥ 34 U/mL, and four imaging features (necrosis (DFS, P = 0.066; OS, P = 0.002), possible venous invasion (DFS, P = 0.150, OS, P = 0.055), suspected metastatic regional lymph node (DFS, P = 0.001; OS, P = 0.099), and associated pancreatitis or pseudocyst (DFS, P = 0.013; OS, P = 0.041)) were included to build the nomogram. The c-statistics for the discrimination power of the proposed nomogram was 0.6496 for DFS and 0.6746 for OS. Conclusion: A nomogram derived from preoperative CT and clinical information could estimate the risk of recurrence and all-cause death after curative-intent surgery for radiologically resectable pancreatic head cancer.

Clinical use of contrast-enhanced ultrasound beyond the liver: a focus on renal, splenic, and pancreatic applications

Contrast-enhanced ultrasound (CEUS) is a relatively novel, but increasingly used, diagnostic imaging modality. In recent years, due to its safety, quickness, and repeatability, several studies have demonstrated the accuracy, specificity, and sensitivity of CEUS. The European Federation of Societies for Ultrasound in Medicine and Biology has recently updated the previous guidelines from 2012 for the use of CEUS in non-hepatic applications. This review deals with the clinical use and applications of CEUS for the evaluation of non-hepatic abdominal organs, focusing on renal, splenic, and pancreatic applications.

A prospective study on endoscopic ultrasound for the differential diagnosis of serous cystic neoplasms and mucinous cystic neoplasms

Background

To provide criteria for the differential diagnosis of serous cystic neoplasms (SCNs) and mucinous cystic neoplasms (MCNs) by analyzing the imaging features of these two neoplasms by endoscopic ultrasound (EUS).

Methods

From April 2015 to December 2017, a total of 69 patients were enrolled in this study. All patients were confirmed to have MCNs (31 patients) or SCNs (38 patients) by surgical pathology. All patients underwent EUS examination. The observation and recorded items were size, location, shape, cystic wall thickness, number of septa, and solid components.

Results

Head/neck location, lobulated shape, thin wall and > 2 septa were the specific imaging features for the diagnosis of SCNs. When any two imaging features were combined, we achieved the highest area under the curve (Az) (0.824), as well as the appropriate sensitivity (84.2%), specificity (80.6%), positive predictive value (PPV) (84.2%), and negative predictive value (NPV) (80.6%). Body/tail location, round shape, thick wall and 0–2 septa were the specific imaging features for the diagnosis of MCNs. When any three imaging features were combined, we obtained the highest Az value (0.808), as well as the appropriate sensitivity (77.4%), specificity (84.2%), PPV (80.0%) and NPV (82.1%).

Conclusions

Pancreatic cystadenomas that meet any two of the four imaging features of head/neck location, lobulated shape, thin wall and > 2 septa could be diagnosed as SCNs, and those that meet any three of the four imaging features of body/tail location, round shape, thick wall and 0–2 septa could be considered as MCNs.

Trial registration

The study was registered at the Chinese Clinical Trial Registry. The registration identification number is ChiCTR-OOC-15006118. The date of registration is 2015-03-20.

Giant serous cystadenoma of the pancreas appearing sonographically as a remote pararenal mass

Macrocystic serous cystadenoma (MSC) of the pancreas is a rare benign neoplasm with varied imaging appearances. We describe an intriguing case of a surgically resected and histologically proven giant MSC, developed in the pararenal space. Ultrasonography (US) revealed a large, oligocystic mass around the lower pole of right kidney. Like US, computed tomography, and magnetic resonance imaging were unable to detect the origin of the lesion, which was only verified at surgical exploration. A bizarre finding was the unusual location of the pancreatic tumor growing seemingly apart from the pancreas itself, with no obvious connection to it.

Pancreatic Ultrasound: State of the Art

An ultrasound (US) study is often the first imaging approach in patients with abdominal symptoms or signs related to abdominal diseases, and it is often part of the routine workup. The pancreatic gland, despite its retroperitoneal site, can be efficiently examined with US thanks to advances in US technologies. Nowadays, a pancreatic US study could be considered complete if multiparametric, including the use of Doppler imaging, US elastography, and contrast-enhanced imaging for the study of a pancreatic mass. A complete US examination could contribute to a faster diagnosis, especially if the pancreatic lesion is incidentally detected, addressing second-step imaging modalities correctly.

Role of computed tomography and magnetic resonance imaging in local complications of acute pancreatitis

Acute pancreatitis (AP) represents a pancreas inflammation of sudden onset that can present different degrees of severity. AP is a frequent cause of acute abdomen and its complications are still a cause of death. Biliary calculosis and alcohol abuse are the most frequent cause of AP. Computed tomography (CT) and magnetic resonance imaging (MRI) are not necessary for the diagnosis of AP but they are fundamental tools for the identification of the cause, degree severity and AP complications. AP severity assessment is in fact one of the most important issue in disease management. Contrast-enhanced CT is preferred in the emergency setting and is considered the gold standard in patients with AP. MRI is comparable to CT for the diagnosis of AP but requires much more time so it is not usually chosen in the emergency scenario. Complications of AP can be distinguished in localized and generalized. Among the localized complications, we can identify: acute peripancreatic fluid collections (APFC), pseudocysts, acute necrotic collections (ANC), walled off pancreatic necrosis (WOPN), venous thrombosis, pseudoaneurysms and haemorrhage. Multiple organ failure syndrome (MOFS) and sepsis are possible generalized complications of AP. In this review, we focus on CT and MRI findings in local complications of AP and when and how to perform CT and MRI. We paid also attention to recent developments in diagnostic classification of AP complications.

Management of Intraductal Papillary Mucinous Neoplasms: Controversies in Guidelines and Future Perspectives

Purpose of review

Management of intraductal papillary mucinous neoplasm (IPMN) is currently based on consensus, in the absence of evidence-based guidelines. In recent years, several consensus guidelines have been published, with distinct management strategies. In this review, we will discuss these discrepancies, in order to guide treating physicians in clinical management.

Recent findings

The detection rate of pancreatic cysts has increased substantially with the expanded use of high-quality imaging techniques to up to 45%. Of these cysts, 24–82% are IPMNs, which harbour a malignant potential. Timely detection of high-risk lesions is therefore of great importance. Surgical management is based on the presence of clinical and morphological high-risk features, yet the majority of resected specimens appear to be low risk.

Summary

International collaboration and incentive large-scale prospective registries of individuals undergoing cyst surveillance are needed to accumulate unbiased data and develop evidence-based guidelines. Additionally, development of non-invasive, accurate diagnostic tools (e.g. biomarkers) is needed to differentiate between neoplastic and non-neoplastic pancreatic cysts and detect malignant transformation at an early stage (i.e. high-grade dysplasia).

Incidental, Small (< 3 cm), Unilocular, Pancreatic Cysts: Factors That Predict Lesion Progression during Imaging Surveillance

OBJECTIVE

To explore the features that predict size increase and development of potential malignant features in incidentally detected, unilocular cystic pancreatic lesions (CPLs) less than 3 cm in diameter, during subsequent follow-up.

MATERIALS AND METHODS

We retrieved data of patients diagnosed with unilocular CPLs less than 3 cm in diameter during the period from November 2003 through December 2014, using a computerized search. All serial CT and MR images were analyzed to identify the number, size, and location of CPLs; dilatation of the main pancreatic duct; and occurrence of worrisome features and high-risk stigmata of malignancy in the lesion. The characteristics of CPLs were compared between the increase (i.e., size increase during subsequent follow-up) and no-increase groups. For CPLs in the increase group, subgroup analysis was performed according to the lesion size at the last follow-up (< 3 cm vs. ≥ 3 cm).

RESULTS

Among 553 eligible patients, 132 (23.9%) had CPLs that increased in size, and 421 (76.1%) had CPLs that did not, during follow-up. Of the 132, 12 (9.1%) CPLs increased to diameters ≥ 3 cm at the final follow-up. Among the various factors, follow-up duration was a significant independent factor for an interval size increase of CPLs (p < 0.001). In the increase group, initial cyst size was a significant independent factor to predict later size increase to or beyond 3 cm in diameter (p < 0.001), and the initial cyst diameter ≥ 1.5 cm predicted such a growth with a sensitivity and specificity of 83% and 72%, respectively. No significant factors to predict the development of potential malignant features were identified.

CONCLUSION

Follow-up duration was associated with an interval size increase of CPLs. Among the growing CPLs, initial cyst size was associated with future lesion growth to and beyond 3 cm.

A Giant Primary Retroperitoneal Serous Cystadenoma: Case Report and Review of Retroperitoneal Cysts

Primary retroperitoneal serous cystadenomas (PRSCs) are rare cystic lesions whose pathogenesis is currently not well understood. Although the vast majority of tumors are benign, early recognition and resection is necessary to avoid malignant transformation, rupture, and secondary infection. Here we present the case of a 79-year-old woman who presented with confusion, visual hallucinations, and a history of fall. As part of the work-up for abdominal distension, computed tomography scan of the abdomen and pelvis was performed, which revealed a right-sided retroperitoneal cystic lesion measuring 26.6 × 16.7 cm in size. The lesion was resected laparoscopically, and the surgical specimen measured 28 × 17 cm. Histology revealed a serous cystadenoma. The postsurgical course was uneventful, and no radiological recurrence was noted on 3 months follow-up. Very few primary retroperitoneal cystic lesions have been reported in the literature. Most lesions are benign and predominantly occur in females. They may remain asymptomatic for long periods of time and are usually discovered when they reach very large in size. In rare cases, these lesions may have malignant potential. Diagnosis of PRSC should be considered in the differential diagnosis of all retroperitoneal cysts.

Serous pancreatic neoplasia, data and review

AIM

To describe the imaging features of serous neoplasms of the pancreas using ultrasound, endoscopic ultrasound, computed tomography and magnetic resonance imaging.

METHODS

This multicenter international collaboration enhances a literature review to date, reporting features of 287 histologically confirmed cases of serous pancreatic cystic neoplasms (SPNs).

RESULTS

Female predominance is seen with most SPNs presenting asymptomatically in the 5^th through 7^th decade. Mean lesion size was 38.7 mm, 98% were single, 44.2% cystic, 46% mixed cystic and solid, and 94% hypoechoic on B-mode ultrasound. Vascular patterns and contrast-enhancement profiles are described as hypervascular and hyperenhancing.

CONCLUSION

The described ultrasound features can aid differentiation of SPN from other neoplastic lesions under most circumstances.

A 7-Year-Old Girl with Early Developed Pseudocyst After Acute Pancreatitis: A Case Report and Literature Review

We report a 7-year-old Taiwanese girl with acute pancreatitis (AP) complicated with pseudocyst (PC). The girl was found to have a PC by ultrasonograpgy (USG) and magnetic resonance imaging 14 days after the onset of AP. The girl was discharged 21 days after management with an asymptomatic PC. The diagnostic criteria of AP included abdominal pain, serum amylase or lipase level, and imaging findings. Transabdominal USG after appropriate preparation with adequate fasting, intake of some liquids during the scanning, and right decubitus position enhance the demonstration of pancreas and peripancreatic structures. PC could be seen in up to 38% of pediatric AP patients. It can form within 2 weeks after the onset of symptoms, although most are late complications. Pancreatic PCs have to be differentiated from other intra-abdominal cysts on USG according to their image character and anatomic location. A well-prepared USG examination in combination with liquid intake and right decubitus position is of value in the diagnosis and follow-up of PC.

Abbreviations: ANC, acute necrotic collection; AP, acute pancreatitis; APFC, acute peripancreatic fluid collection; CECT, contrast-enhanced computed tomography; CRP, C-reactive protein; CT, computed tomography; MRI, magnetic resonance imaging; PAP, pediatric acute pancreatitis; PC, pseudocyst; USG, ultrasonography.

Endoscopic ultrasonography evaluation for pancreatic cysts: Necessity or overkill?

Incidental pancreatic cysts have become gradually more recognized in clinical practice as a result of increased use of transabdominal ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). These lesions consist of inflammatory cysts (pseudocysts) and pancreatic cystic neoplasms (PCN) which have been classified as benign, premalignant and malignant. The diagnosis and management strategy of incidentally discovered pancreatic cysts can be challenging as the majority of them are PCN and CT or MRI alone may not be sufficient to provide an accurate diagnosis. Endoscopic ultrasound (EUS)-guided fine-needle aspiration provides a method to obtain cyst fluid for analysis and the recently developed EUS-based technology including contrast-enhanced ultrasound, cystoscopy and needle-based confocal laser endomicroscopy allows endosonographers to gain additional useful information. The current data suggest that EUS evaluation of pancreatic cysts offers some benefits especially in cases of inconclusive CT or MRI.

The diagnostic challenge of the sequelae of acute pancreatitis on CT imaging: a pictorial essay

PURPOSE

The purpose of the study was to present a pictorial review of the long-term sequelae of acute pancreatitis on CT imaging as these findings can cause diagnostic confusion in the absence of a proper clinical history and/or prior CT imaging.

METHODS

We retrospectively identified 81 patients who had an episode of acute pancreatitis with diagnostic findings on CT and also underwent one or more follow-up CT scans at least 1 month beyond the acute episode. The residual findings on all follow-up CT scans were tabulated, including the time interval since the initial bout of acute pancreatitis.

RESULT

Residual inflammatory changes were present in 19.8% of cases, with a median time period lasting 86 days since the initial episode of acute pancreatitis. Residual fluid collections were seen in 27.2% and persisted for a median of 132 days. Three patients had residual solid-appearing inflammatory masses, which could be mistaken for neoplasms. Other long-term sequelae were also tabulated, including pancreatic ductal dilatation, pancreatic atrophy, new or increased pancreatic calcifications, biliary tract dilatation, central portal venous occlusion, and pseudoaneurysm formation. These residual findings and long-term complications are presented as a pictorial essay.

CONCLUSION

Recognizing the spectrum of residual findings of acute pancreatitis, some of which can be long term, is important in the correct interpretation of a pancreatic CT. These findings can mimic acute pancreatitis or a pancreatic/peripancreatic neoplasm and often cause diagnostic confusion, especially in the absence of prior CT imaging.

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.

Pancreatic cysts: What imaging characteristics are associated with development of pancreatic ductal adenocarcinoma?

PURPOSE

To assess relationship between pancreatic cysts (PC) and pancreatic ductal adenocarcinoma (PDAC) and to compare imaging features of PC in subjects who develop PDAC and those who do not.

MATERIAL AND METHODS

This case-control IRB-approved HIPAA-compliant study included patients with PDAC (cases) and lung cancer (controls), diagnosed between 1/1/05-1/1/14. The most recent abdominal CT/MR of each patient done >6months prior to cancer diagnosis date was reviewed by radiologist blinded to case/control status. Presence of PC, number and size of largest PC, presence of main pancreatic duct (MPD) dilatation (MPD >3mm) were recorded. Simple PC was defined as lack of calcifications, septations and enhancement. Logistic regression models with binary outcome of PDAC were constructed.

RESULTS

There were 88 cases and 273 controls with mean ages of 69.6 years (±10.3) and 69.8 years (±12.0), respectively (p=0.864). PC were present in 21.6% (19/88) cases and in 9.2% (25/273) controls (p=0.002). The OR of PC for development of PDAC was 2.83, adjusting for age, sex and race (p=0.001). Mean PC size was 14.8mm (±8.7) in cases and 7.6mm (±8.0) in controls (p=0.007). PC were solitary in 6 (31.6%) of 19 cases and 21 (84.0%) of 25 controls (p=0.001). There was no significant difference in proportions of simple cysts or MPD dilatation between cases and controls. Multiple PC had 8.2 times increased odds of PDAC compared with solitary PC, adjusting for cyst size (p=0.007).

CONCLUSION

Multiple PC are associated with 8.2 times higher odds of PDAC compared with solitary PC.

Advanced endoscopic ultrasound management techniques for preneoplastic pancreatic cystic lesions

Pancreatic cystic lesions can be benign, premalignant or malignant. The recent increase in detection and tremendous clinical variability of pancreatic cysts has presented a significant therapeutic challenge to physicians. Mucinous cystic neoplasms are of particular interest given their known malignant potential. This review article provides a brief but comprehensive review of premalignant pancreatic cystic lesions with advanced endoscopic ultrasound (EUS) management approaches. A comprehensive literature search was performed using PubMed, Cochrane, OVID and EMBASE databases. Preneoplastic pancreatic cystic lesions include mucinous cystadenoma and intraductal papillary mucinous neoplasm. The 2012 International Sendai Guidelines guide physicians in their management of pancreatic cystic lesions. Some of the advanced EUS management techniques include ethanol ablation, chemotherapeutic (paclitaxel) ablation, radiofrequency ablation and cryotherapy. In future, EUS-guided injections of drug-eluting beads and neodymium:yttrium aluminum agent laser ablation is predicted to be an integral part of EUS-guided management techniques. In summary, International Sendai Consensus Guidelines should be used to make a decision regarding management of pancreatic cystic lesions. Advanced EUS techniques are proving extremely beneficial in management, especially in those patients who are at high surgical risk.

Requirement of a single high-risk feature as an indication for EUS for the diagnosis of asymptomatic pancreatic cysts

BACKGROUND AND AIMS

Endoscopic ultrasound (EUS) is widely used to evaluate pancreatic cysts. Recent American Gastroenterological Association (AGA) guideline limits EUS for evaluation of cysts with at-least two high-risk features (size ≥ 3 cm, dilated main pancreatic duct or presence of a solid component). We have investigated the impact of this guideline on sensitivity of EUS for pancreatic cancer and the reduction of EUS procedures for pancreas cysts.

METHODS

EUS procedures performed between 2004 and 2015 and related patient records were retrospectively reviewed to determine the presence or absence of high-risk features, and for the results of fine needle aspiration cytology.

RESULTS

Two hundred ten patients (108 males) underwent EUS for diagnostic evaluation of pancreatic cysts. Four patients (1.9%), all with at-least one high-risk feature, were diagnosed with cytologically-proven pancreatic cancer. Only 2 patients with cancer had at-least two high-risk features that would have warranted EUS examination based on the new AGA guideline. The requirement for at-least two high-risk features would have decreased the number of EUS procedures by 91%, but reduced the sensitivity for pancreatic malignancy to 50%. If only one high-risk feature was required, EUS procedures would have been decreased by 67%, with a sensitivity of 100%.

CONCLUSION

Limiting EUS to patients with pancreatic cysts with 2 or more high-risk features may substantially reduce the sensitivity for pancreatic malignancy. Performing EUS in patients with at least one high-risk feature may substantially decrease the need of invasive procedures without reducing sensitivity for detecting malignancy.

Clinics in diagnostic imaging (168)

A 16-year-old Chinese male patient presented with constipation lasting five days, colicky abdominal pain, lethargy, weakness and body aches. He was able to pass flatus. Abdominal radiography showed a distended stomach causing inferior displacement of the transverse colon. Computed tomography revealed a dilated oesophagus, stomach and duodenum up to its third portion, with a short aortomesenteric distance and narrow angle. There was also consolidation in the lungs bilaterally. Based on the constellation of clinical and imaging findings, a diagnosis of superior mesenteric artery syndrome complicated by aspiration pneumonia was made. The patient was subsequently started on intravenous hydration, nasogastric tube aspiration and antibiotics. Following stabilisation of his acute condition, a nasojejunal feeding tube was inserted and a feeding plan was implemented to promote weight gain. The clinical presentation, differentials, diagnosis and treatment of superior mesenteric artery syndrome are discussed.

Contrast-enhanced ultrasound of pancreatic tumours

Indication/purpose: To review contrast‐enhanced ultrasound features of the most common pancreatic tumours.

Methods: Contrast‐enhanced ultrasound (CEUS) can provide distinctive features of pancreatic tumours that are reported in the present paper, providing radiologic‐pathological correlations and clarifying the main differential diagnosis.

Conclusion: Contrast‐enhanced ultrasound plays a well‐established role in the evaluation of pancreatic tumours. When possible, CEUS should be always performed after the initial US diagnosis, in order to improve the accuracy of the first line examination.

[Cystic lesions of the pancreas]

Due to the widespread use of computed tomography (CT) and magnetic resonance imaging (MRI) of the abdomen, the incidence of cystic pancreatic lesions as an incidental finding in asymptomatic patients is increasing; however, most of these lesions are less than 2 cm in size at the time of diagnosis making a correct classification difficult. A more differentiated understanding of the pathophysiology of these lesions has been developed during recent years. Technical improvements in imaging techniques have resulted in an increase in image resolution and has enabled radiologists to differentiate between intraductal papillary mucinous neoplasms (IPMN), serous cystic neoplasms (SCN) and mucinous cystic neoplasms (MCN). A correct classification, including the differentiation from malignant pancreatic tumors, can only be achieved by combining the knowledge of lesion pathophysiology and basic epidemiological data, such as age and sex distribution with modern imaging techniques. In conjunction with the correct diagnosis, the radiologist has to decide on the further management of the newly found lesion. This differs greatly depending on the biological behavior, especially the potential for malignant transformation, e.g. in main duct IPMN. This review gives an overview of the different cystic pancreatic lesions, their underlying pathophysiology and imaging characteristics along with recommendations for the further clinical management.

Evaluation of Qualitative Magnetic Resonance Imaging Features for Diagnosis of Chronic Pancreatitis

OBJECTIVES

The purpose of this study was to determine qualitative pancreatic magnetic resonance imaging (MRI) features that must be present to predict abnormal pancreatic secretory function in patients evaluated for chronic pancreatitis (CP).

METHODS

The MRIs of study subjects were reviewed by 2 abdominal radiologists; qualitative parenchyma and ductal features were recorded. Endoscopic pancreatic function test (ePFT) results (reference standard) were classified as normal (peak pancreatic fluid bicarbonate [HCO3-] ≥75 meq/L) or abnormal (<75). Abnormal ePFT was further classified as mild/moderate (74-65) and marked deficiency (<65). Statistical analysis was performed to assess the association between MRI features and abnormal ePFT.

RESULTS

The study cohort was composed of 93 subjects, mean age 49 years (range, 18-78 years), 65% females. Univariate analysis identified 9 qualitative MRI features significantly (P < 0.05) associated with abnormal pancreatic secretory function. Number of MRI features increases as peak pancreatic fluid [HCO3-] decreases (Pearson r = -0.629; P = 0.001). Receiver operating characteristic curve analysis determined that a threshold of 6 or more associated MRI features 64% sensitive and 94% specific for marked bicarbonate deficiency.

CONCLUSIONS

Qualitative MRI parenchymal and ductal features are associated with CP. Presence of 6 or more features results in a higher specificity for the diagnosis of CP in advanced disease.

Imaging of pancreatic neoplasms

Ductal adenocarcinoma accounts for 85% to 90% of all solid pancreatic neoplasms, is increasing in incidence, and is the fourth leading cause of cancer-related deaths. There are currently no screening tests available for the detection of ductal adenocarcinoma. The only chance for cure in pancreatic adenocarcinoma is surgery. Imaging has a crucial role in the identification of the primary tumor, vascular variants, identification of metastases, disease response assessment to treatment, and prediction of respectability. Pancreatic neuroendocrine neoplasms can have a distinctive appearance and pattern of spread, which should be recognized on imaging for appropriate management of these patients.

CEUS of the pancreas: Still research or the standard of care

Contrast-enhanced ultrasonography (CEUS) improves the characterization of pancreatic masses. CEUS is in fact a safe and accurate imaging method to evaluate the vascularity of pancreatic lesions. CEUS should be performed when possible immediately after the ultrasound (US) detection of a pancreatic mass. CEUS is accurate in the characterization of ductal adenocarcinoma. The use of CEUS in studying pancreatic lesions found at US, especially in the same session of ultrasound examination, is therefore recommendable to promote faster diagnosis mainly of pancreatic ductal adenocarcinoma.

Severe Hypertriglyceridemia Causing Acute Pancreatitis in a Child with New Onset Type I Diabetes Mellitus Presenting in Ketoacidosis

A 10 year old girl presented with severe diabetic ketoacidosis (DKA) and a hemoglobin A1C of 17.9%. On hospital day 2 after acidosis had improved it worsened and she developed excruciating abdominal pain. Her serum triglycerides and lipase levels were found to be extremely high and ultrasound analysis of the pancreas was consistent with acute pancreatitis. She was diagnosed with acute pancreatitis secondary to hypertriglyceridemia. The pancreatitis resolved completely and two months later her hemoglobin A1C was 8.2% and the serum triglycerides were normal. Severe hypertriglyceridemia from insulin deficiency causing pancreatitis in new onset type 1 diabetes mellitus is a rare but serious complication of DKA in children.

Application of Contrast-Enhanced Ultrasound in Cystic Pancreatic Lesions Using a Simplified Classification Diagnostic Criterion

Objective. Classification diagnosis was performed for cystic pancreatic lesions using ultrasound (US) and contrast-enhanced ultrasound (CEUS) to explore the diagnostic value of CEUS by comparison with enhanced CT. Methods. Sixty-four cases with cystic pancreatic lesions were included in this study. The cystic lesions of pancreas were classified into four types by US, CEUS, and CT: type I unilocular cysts; type II microcystic lesions; type III macrocystic lesions; and type IV cystic lesions with solid components or irregular thickening of the cystic wall or septa. Results. Eighteen type I, 7 type II, 10 type III, and 29 type IV cases were diagnosed by CT. The classification results by US were as follows: 6 type I; 5 type II; 4 type III; and 49 type IV cases. Compared with the results by enhanced CT, the kappa value was 0.36. Using CEUS, 15, 6, 12, and 31 cases were diagnosed as types I–IV, respectively. The kappa value was 0.77. Conclusion. CEUS has obvious superiority over US in the classification diagnostic accuracy in cystic pancreatic lesions and CEUS results showed substantial agreement with enhanced CT. CEUS could contribute to the differential diagnosis of cystic pancreatic diseases.

Incidental pancreatic cysts: role of magnetic resonance imaging

The widespread adoption of multidetector computed tomography and magnetic resonance imaging (MRI) for evaluation of intraabdominal pathology has resulted to a steady increase in the number of incidentally discovered pancreatic cysts in clinical practice during the last decades. The differential diagnosis of these cysts is broad including pseudocysts, serous cystic neoplasms, mucinous cystic neoplasms, and intraductal papillary mucinous neoplasms. The MRI has an important role both in the initial characterization of incidentally detected pancreatic cysts and the follow-up of these lesions and has become an integral part of the diagnostic algorithm for pancreatic cysts at many institutions. The inherent soft-tissue contrast of magnetic resonance cholangiopancreatography provides the vehicle for providing a specific diagnosis in many pancreatic cysts. Furthermore, an MRI-based characterization of pancreatic cysts allows for selection of those cysts that are more likely to benefit from endoscopic ultrasound and fine-needle aspiration for analysis of the fluid contents. Moreover, small asymptomatic incidental pancreatic cysts without concerning MRI features such as internal septae and/or nodularity may be safely followed with serial imaging. The lack of risk associated to repeated exposure to ionizing radiation and its ability to characterize pancreatic cysts are strong arguments for selecting MRI as the preferred imaging modality for following up these lesions. However, the recommendations for imaging follow-up continue to evolve, and several of the proposed guidelines are reviewed in this manuscript.

A disseminated variant of pancreatic serous cystadenoma causing obstructive jaundice, a very rare entity: a case report and review of the literature

Background

Microcystic adenoma or serous cystadenoma (SCA) is an uncommon tumor type, accounting for only 1–2% of pancreatic exocrine neoplasms. Usually unifocal, SCAs present as single, large, well-demarcated, multiloculated, cystic tumors, 1–25 cm in size.

Case presentation

A 73-year-old man initially presented with epigastric abdominal pain and was diagnosed with SCA involving the whole pancreas. Eleven months later, he presented with obstructive jaundice, and total pancreatectomy was performed. The removed tissue allowed histological verification of pancreatic SCA. Histopathological examination showed both microcysts and macrocysts, lined by cuboidal epithelium, with optically clear cytoplasm and the absence of detectable mitosis or necrosis.

Conclusions

Thus, although relatively rare, pancreatic SCA is one of the differential diagnoses of epigastric abdominal pain; we recommend early surgical intervention for symptomatic pancreatic SCA.

Imaging of pediatric pancreatic neoplasms with radiologic-histopathologic correlation

OBJECTIVE

The purpose of this article is to describe the imaging features of pediatric pancreatic tumors with pathologic correlation. Epithelial and nonepithelial lesions are described. Pancreatic imaging protocols, clinical presentation, and management are also detailed.

CONCLUSION

Pancreatic neoplasms are rare in children and vary widely between benign and malignant causes and between cystic and solid lesions. Epithelial tumors are most common and include solid pseudopapillary tumor, pancreatoblastoma, islet cell neoplasms, and cystic lesions.

To fine needle aspiration or not? An endosonographer's approach to pancreatic cystic lesions

Endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) is an established diagnostic tool in the management of pancreatic cystic lesions (PCLs). Due to the proximity to the target lesion, the fine diagnostic needle travels through only minimal normal tissues. The risks of bleeding, pancreatitis and infection are small. Valuable diagnostic morphological information can be obtained by EUS before the use of FNA. The additional cytopathologic and cyst fluid analysis for the conventional markers such as amylase, carcinoembryonic antigen (CEA) and CA19.9 improves the diagnostic capability. Pancreatic cyst fluid CEA concentration of 192 ng/mL is generally the most agreed cutoff to differentiate mucinous from non-mucinous lesion. A fluid amylase level of <250 IU/L excludes the diagnosis of pseudocyst. Technical tips of EUS-FNA and the limitations of the procedure are discussed. Promising technique and FNA needle modifications have been described to improve the diagnostic yield at the cytopathologic analysis. The use of novel cyst fluid proteomics and deoxyribonucleic acid-based biomarkers of the PCLs are reviewed. Although it is considered a safe procedure, EUS-FNA is not a routine in every patient. Recommendations of the role of EUS-FNA at various common clinical scenarios are discussed.

Imaging of acute pancreatitis and its complications. Part 2: complications of acute pancreatitis

The Atlanta classification of acute pancreatitis was introduced in 1992 and divides patients into mild and severe groups based on clinical and biochemical criteria. Recently, the terminology and classification scheme proposed at the initial Atlanta Symposium have been reviewed and a new consensus statement has been proposed by the Acute Pancreatitis Classification Working Group. Major changes include subdividing acute fluid collections into "acute peripancreatic fluid collection" and "acute post-necrotic pancreatic/peripancreatic fluid collection (acute necrotic collection)" based on the presence of necrotic debris. Delayed fluid collections have been similarly subdivided into "pseudocyst" and "walled of pancreatic necrosis". Appropriate use of the new terms describing the fluid collections is important for management decision-making in patients with acute pancreatitis. The purpose of this review article is to present an overview of complications of the acute pancreatitis with emphasis on their prognostic significance and impact on clinical management and to clarify confusing terminology for pancreatic fluid collections.

Fluid collections associated with acute pancreatitis: a pictorial essay

The terminology and classification scheme of acute pancreatitis proposed at the initial Atlanta Symposium was reviewed, and a new consensus statement was recently proposed. Major changes include subdividing acute fluid collections in the first 4 weeks into "acute peripancreatic fluid collection" and "acute necrotic collection" based on the presence of necrotic debris. Delayed fluid collections have been similarly subdivided into "pseudocyst" and "walled-off necrosis." Correct use of the new terms that describe these collections is important because they lead to different treatment decisions. The purpose of this article is to present an overview of fluid collections associated with acute pancreatitis, with an emphasis on their prognostic significance and impact on clinical management, and to illustrate the new terminology.

Diagnosis and treatment of pancreatic pseudocysts and cystic tumors based on own material and quoted literature

Pseudocysts constitute the most basic cystic lesions of the pancreas. Symptomatic cysts may be treated by means of both minimally invasive methods and surgery. Currently, it is believed that approximately 5% of cystic lesions in the pancreas may in fact, be neoplastic cystic tumors. Their presence is manifested by generally irregular multilocular structures, solid nodules inside the cyst or in the pancreatic duct, frequently vascularized, as well as fragmentary thickening of the cystic wall or septation.