Mucinous cystic neoplasm of the pancreas

Mucinous cystadenoma of the pancreas associated with pregnancy. Case report and review of the literature

Objective. We present a rare pathology with uncommon onset. Background. Mucinous cystic pancreatic neoplasms (MCNs) are rare tumors, which generally occur in the fifth and sixth decades of women. Although some tumours are frankly malignant, all are in fact considered to be potentially malignant. Case report. We present the case of a 30-year-old patient, with a 16/11 cm tumor located in the pancreas body, which was diagnosed 8 months after birth. The preoperative assessment of the pancreatic lesion suggested the diagnosis of mucosal cyst neoplasm, without being able to determine its benign or malignant nature. Central pancreatectomy was performed with a good postoperative evolution. Histopathologic result was represented by mucinous pancreatic chistadenoma. Two years after surgical intervention, the patient presented no signs of recurrence or pancreatic (exocrine or endocrine) secretion deficiency. Conclusions. Preoperative imaging evaluation could be suggestive for mucinous cystic tumour, but this cannot specify however the nature of the tumor. The postpartum occurrence could establish a possible relationship between hormonal levels encountered during pregnancy and the development of this tumor, taking into considerations the ovarian-type stroma and the presence of hormone (estrogen and progesterone) receptors in this neoplasm. Central pancreatectomy without anastomosis preserves the functions of pancreas, and also decreases morbidity.

Mucinous cystadenoma of pancreas with honeycombing appearance: Radiological-Pathological correlation

Most mucinous cystadenomas of pancreas are solitary and multilocular with a few large compartments. Serous cystadenomas usually have a polycystic or microcystic (honeycomb) pattern consisting of collection of cysts (usually >6) that range from few millimetres up to 2 cm in size. Here we present a case of mucinous cystadenoma of pancreas showing an unusual appearance of honeycombing (which has not been described so far) using imaging studies such as endoscopic ultrasound and computed tomography with histopathological confirmation of the diagnosis.

Calcified pancreatic and peripancreatic neoplasms: spectrum of pathologies

A variety of pancreatic and peripancreatic neoplasms may contain calcifications. We present a review of common to uncommon pancreatic neoplasms that may contain calcifications to include ductal adenocarcinoma, pancreatic neuroendocrine tumors, serous cystadenomas, solid pseudopapillary tumors, intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, and lymphoepithelial cysts. In addition, duodenal mucinous adenocarcinoma can present as a peripancreatic mass that may contain calcification. Knowledge of the spectrum of calcification patterns can help the interpreting radiologist provide a meaningful differential.

[Diagnostic strategy and differential therapeutic approach for cystic lesions of the pancreas]

CLINICAL/METHODICAL ISSUE

Cystic pancreatic lesions (CPL) are diagnosed with increasing frequency. Because up to 60% of CPL are classified as malignant or premalignant, every CPL should be fully investigated and clarified. Serous CPL with low risk of malignancy must be differentiated from mucinous CPL with relevant potential malignancy (intraductal papillary mucinous neoplasm IPMN) and mucinous cystic neoplasm (MCN) as well as from harmless pseudocysts.

STANDARD RADIOLOGICAL METHODS

Cross-sectional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) plays a crucial role in the diagnostics of CPL.

METHODICAL INNOVATIONS

An algorithm for the differential diagnostic classification of CPL is presented.

PERFORMANCE

The connection to the pancreatic duct is the key diagnostic criterion to differentiate IPMN from all other CPL. An exception to this rule is that pseudocysts can also show a connection to the pancreatic duct. A further classification of CPL with no connection to the pancreatic duct can be made by morphological criteria and correlation of the radiological findings with patient age, sex, history and symptoms.

PRACTICAL RECOMMENDATIONS

Depending on the diagnosis and hence the malignant potential the indications for surgery or watch and wait have to be discussed in an interdisciplinary cooperation. Due to its higher soft tissue contrast MRI is often superior to CT for depiction of CPL morphology.

Magnetic resonance imaging of less common pancreatic malignancies and pancreatic tumors with malignant potential

Pancreatic tumors are an increasingly common finding in abdominal imaging. Various kinds of pathologies of the pancreas are well known, but it often remains difficult to classify the lesions radiologically in respect of type and grade of malignancy. Magnetic resonance imaging (MRI) is the method of choice for the evaluation of pancreatic pathologies due to its superior soft tissue contrast. In this article we present a selection of less common malignant and potentially malignant pancreatic neoplasms with their characteristic appearance on established MRI sequences with and without contrast enhancement.

Part 1: CT characterisation of pancreatic neoplasms: a pictorial essay

The pancreas is a site of origin of a diverse range of benign and malignant tumours, and these are frequently detected, diagnosed and staged with computed tomography (CT). Knowledge of the typical appearance of these neoplasms as well as the features of locoregional invasion is fundamental for all general and abdominal radiologists. This pictorial essay aims to outline the characteristic CT appearances of the spectrum of pancreatic neoplasms, as well as important demographic and clinical information that aids diagnosis. The second article in this series addresses common mimics of pancreatic neoplasia.

Pancreatic mucinous cystadenoma communicating with the main pancreatic duct on MRI

We report a case of a mucinous cystadenoma of the pancreas communicating with the main pancreatic duct. To our knowledge, this is the first case in which a communication between the mucinous cystadenoma and the main pancreatic duct could be demonstrated by MRI.

Role of endosocopic ultrasound in the diagnosis of cystic tumours of the pancreas

With the increased use of sophisticated imaging, cystic lesions in the pancreas are being recognized with greater frequency. Although imaging alone may not provide a specific diagnosis in many cases, a combination of imaging characteristics, clinical presentation, and additional procedures such as endoscopic ultrasound guided fine needle aspiration of cystic lesion, allows appropriate management. Cystic lesions in the pancreas can be divided pathologically into congenital cysts, pseudocysts and cystic neoplasm. At least four different types of cystic neoplasm have been described: mucinous neoplasms, intraductal papillary mucinous neoplasms, serous neoplasms and papillary cystic neoplasms The most important diagnosis is differentiating between mucinous and non-mucinous cystic lesion because of their different potential of malignancy. Endoscopic ultrasound provides the highest resolution of the pancreas and endoscopic ultrasound-fine needle aspiration can supply further diagnostic information on the basis of cytology, fluid viscosity, concentration of tumour glycoproteins, amylase level, molecular analysis that may contribute to the better clinical outcome of these neoplasms.

Comparison of contrast-enhanced sonography and MRI in displaying anatomic features of cystic pancreatic masses

OBJECTIVE

The purpose of this study was to compare the accuracy rates of unenhanced sonography, contrast-enhanced sonography, and MRI in displaying the anatomic features of cystic pancreatic masses larger than 1.5 mm in diameter.

MATERIALS AND METHODS

Unenhanced and contrast-enhanced sonographic and MRI examinations of 33 patients who underwent resection of a cystic pancreatic mass were retrospectively reviewed. Two radiologists blinded to the final histologic diagnosis reviewed the images, specifically assessing the presence of intralesional mural nodules and septa. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated on the basis of correlation with surgical findings. Results of unenhanced sonography, contrast-enhanced sonography, and MRI were compared by McNemar test. Correlation of unenhanced and contrast-enhanced sonographic versus pathologic results was established with Spearman's test. Interobserver variability was determined.

RESULTS

Contrast-enhanced sonography correctly depicted intralesional septa in 14 of 15 lesions (sensitivity, 93.3%; specificity, 88.8%; positive predictive value, 87.5%; negative predictive value, 94.1%; accuracy, 90.9%) and nodules in six of eight lesions (sensitivity, 75%; specificity, 96%; positive predictive value, 85.7%; negative predictive value, 92.3%; accuracy, 90.9%). MRI correctly depicted intralesional septa in 14 of 15 lesions (sensitivity, 93.3%; specificity, 61.1%; positive predictive value, 66.6%; negative predictive value, 91.6%; accuracy, 75.7%) and nodules in seven of eight lesions (sensitivity, 87.5%; specificity, 80%; positive predictive value, 58.3%; negative predictive value, 95.2%; accuracy, 81.8%). The difference between the diagnostic accuracy of contrast-enhanced sonography and that of MRI was not significant (p = 0.05, McNemar test) in the identification of septa and nodules. The correlation between contrast-enhanced sonographic findings and pathologic results (Rs = 0.93; p < 0.001) was significantly better than that between sonographic and pathologic results (Rs = 0.52; p < 0.0001). Interobserver agreement had a kappa value of 0.86-0.94.

CONCLUSION

Contrast-enhanced sonography compares favorably with MRI in displaying the anatomic features of cystic pancreatic masses seen on transabdominal sonography.

[Serous oligocystic adenoma of the pancreas]

Serous oligocystic or macrocystic adenoma of the pancreas is a very uncommon morphological variant of what was classically termed microcystic adenoma of the pancreas. This is a benign neoplasm; however, its radiological appearance mimicks that of potentially malignant mucinous neoplasms of the pancreas. Therefore, radiologists need to be familiar with this entity to ensure the most appropriate therapeutic management and help to avoid unnecessary surgery.

Ultrasonography of the pancreas. 4. Contrast-enhanced imaging

The introduction of contrast-enhanced ultrasonography (CEUS) has lead to great developments in the diagnostic capabilities of ultrasound. Second generation contrast media, characterized by harmonic responses at low mechanical index of the ultrasound beam, have already proven usefulness in the study of the liver but other abdominal organs can take advantage from the dynamic study during continuous ultrasonographic scans. The dynamic observation of the enhancement allows the perfect evaluation of the abdominal organs perfusion. The perfusion of the pancreas is well correlated to the semeiology of the gland parenchymography at CEUS. The study of the pancreas is a new and promising application of CEUS. CEUS can be used to better identify pancreatic lesions respect to conventional Ultrasound (US) or to characterize pancreatic lesions already visible at US. Moreover the staging of some pancreatic lesions can be improved by the use of contrast media. This article will review the clinical application of CEUS in the different pancreatic pathologies.

Cystic neoplasms of the pancreas

This article presents the approach to the most commonly encountered pancreatic cystic masses that the authors employ at the University of Pittsburgh Medical Center. Variations on this approach are to be expected, based on several factors, including the availability of sophisticated imaging equipment and personnel.

Cystic pancreatic tumors (CPT): predictors of malignant behavior

BACKGROUND AND OBJECTIVES

Due to widespread use of imaging studies, increasing cystic pancreatic tumor (CPT) cases are being detected. The diagnosis of malignancy in CPT cases requires pancreatectomy. Clinical and laboratory characteristics of CPT may predict underlying malignancy.

METHODS

CPT cases treated between 1994 and 2004 at our institution were included. Pseudocysts were excluded. Serous cystadenoma (SCA), mucinous cystadenoma (MCA), intrapapillary mucinous tumor, cystic endocrine tumor, and lymphoepithelial cysts were classified as benign or pre-malignant. Serous cystadenocarcinoma (SCACA), mucinous cystadenocarcinoma (MCACA), and adenocarcinoma (ACA) were classified as malignant.

RESULTS

Thirty-five patients had histological confirmation. Median age was 65 years. Male/female ratio was higher in malignant group (P = 0.0284). Weight loss and abdominal mass were more prevalent in malignant group (P = 0.042 and 0.028, respectively). Malignant lesions were larger, associated with local invasion (superior mesenteric artery (SMA), superior mesenteric vein (SMV), portal vein (PV) complex or celiac encasement) and CA 19-9 elevation. On univariate analyses, local invasion (P = 0.0029), negative surgical intervention (P = 0.0010), presence of ACA (P = 0.0044), or malignant CPT (P = 0.0018) were associated with shorter survival. On a multivariate analysis, local invasion was associated with shorter survival [Hazard ratio (HR) = 4.322, P = 0.0218], while surgical intervention was associated with improved survival (HR = 0.179, P = 0.0124).

CONCLUSION

Male sex, abdominal mass, weight loss, larger tumor size, local invasion, and elevated CA 19-9 were associated with malignant CPT.

Multidetector row CT of the pancreas

Multidetector CT (MDCT) has gained a great role in clinical imaging practice in a short time. Its major advantages are faster image acquisition and improved z-axis resolution. In spite of the advent of other imaging modalities CT is still the gold standard for the evaluation of pancreatic pathology. In this article, a review of the utility of MDCT in pancreatic applications is given with emphasis on acquisition techniques tailored to contrast material pharmacokinetics to improve lesion detection and characterization.

Cystic neoplasms of the pancreas and tumor-like lesions with cystic features: a review of 418 cases and a classification proposal

Although cystic neoplasms and lesions of the pancreas are rare, they have attracted a great deal of attention because of their potential curability. Since, in recent years, several new entities have been identified, the relative frequency of the tumors and their classification need to be reevaluated. In a series of 1454 tumorous lesions of the pancreas collected between 1971 and 2003 in our surgical pathology files and consultation files, all cystic pancreatic neoplasms and tumor-like lesions were identified and typed both histologically and immunohistochemically. There were 418 cases (29%) showing cysts with a diameter ranging between 0.5 cm and 27 cm. Most common were solid pseudopapillary neoplasms (21%) and intraductal papillary-mucinous neoplasms (18%). When only the cystic neoplasms and lesions that had been resected in a single institution were considered, intraductal papillary mucinous neoplasms were the most frequent cystic neoplasms, while solid pseudopapillary neoplasms took fifth place behind ductal adenocarcinomas with cystic features, serous cystic neoplasms and mucinous cystic neoplasms. The most frequent cystic tumor-like lesions were pancreatitis-associated pseudocysts. New and rare entities that have recently been identified are mucinous nonneoplastic cysts, acinar cell cystadenomas and cystic hamartomas. Bearing in mind that figures from referral centers such as ours may be biased regarding the relative frequency of lesions, we concluded from our data that intraductal papillary-mucinous neoplasms are the most frequently occurring pancreatic cystic neoplasms, rather than solid pseudopapillary neoplasms. It was possible to classify all cystic lesions encountered in our files or described in the literature in a new system that distinguishes between neoplastic and nonneoplastic lesions, with further subdivisions into epithelial (adenomas, borderline neoplasms and carcinomas) and nonepithelial tumors. This classification is easy to handle and enables a distinction on the basis of clinical behavior and prognosis.

Cystic pancreatic neoplasms

Cystic pancreatic neoplasms are uncommon, but are being seen more frequently due to the widespread use of cross-sectional imaging. In this article, we will address the clinical and imaging features of the more commonly seen neoplasms. Points of differentiation between these neoplasms, the use of cyst fluid analysis and an approach to the incidentally discovered cystic mass will be addressed.

Imaging of cystic diseases of the pancreas

Although the majority of cystic lesions of the pancreas seen in clinical practice represent postinflammatory pseudocysts, it is important for the radiologist to be knowledgeable of the wide spectrum of cystic masses of the pancreas and the variable prognoses they possess. As a result of similarities in the imaging features of these lesions, a definitive diagnosis is often not possible. By combining imaging features with clinical history, a reasonable differential diagnosis can be offered to the referring physician. In some cases, biopsy or fluid aspiration may be required prior to surgery. In a patient without the appropriate history of pancreatitis and the presence of a cystic pancreatic mass, it is incumbent upon the radiologist to offer alternative diagnoses of cystic neoplasms of the pancreas.