The differentiation between pancreatic neoplastic cysts and pancreatic pseudocyst

Role of Cross-sectional Imaging (CT/MRI) in Characterization and Distinguishing Benign from Malignant/Potentially Malignant Cystic Lesions of Pancreas

Objectives:

The aim of the study was to evaluate the accuracy of computed tomography/magnetic resonance imaging (CT/MRI) in characterizing cystic lesions of the pancreas and in differentiating between benign and malignant/potentially malignant lesions.

Material and Methods:

A retrospective study was performed on patients with pancreatic cystic lesions who underwent pre-operative imaging and surgery between October 2004 and April 2017 at a tertiary care teaching hospital. The images were reviewed for specific characteristics and diagnoses recorded independently by two radiologists who were blinded to the histopathological examination (HPE) report. Radiological diagnostic accuracy was assessed with HPE as reference standard.

Results:

A total of 80 patients fulfilled the inclusion criteria (M: F = 27:53). The final HPE diagnoses were solid pseudopapillary neoplasm (32.5%), walled off necrosis/pseudocyst (27.5%), mucinous cystadenoma (15%), serous cystadenoma (11.25%), intraductal papillary mucinous neoplasm (8.75%), mucinous cystadenocarcinoma (2.5%), simple epithelial cyst (1.25%), and unspecified benign cystic lesion (1.25%). Observer1 correctly identified the diagnosis in 73.75% of cases while observer 2 did so in 72.5%. Sensitivity for distinguishing benign versus malignant/potentially malignant lesions was 85.1% for observer 1 and 80.9% for observer 2. On multivariate logistic regression analysis: Solid cystic morphology, presence of mural nodule, and female gender were associated with premalignant/malignant lesions.

Conclusion:

Cross-sectional imaging is a valuable tool for characterization of pancreatic cystic lesions within its limitations.

Cyst Features and Risk of Malignancy in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Imaging and Pathology

Background

Intraductal papillary mucinous neoplasms (IPMNs) display diverse macroscopic, histological, and immunohistochemical characteristics with typical morphological appearance in magnetic resonance imaging. Depending on those, IPMNs may show progression into invasive carcinomas with variable frequency. Overall, IPMN-associated invasive carcinomas are found in about 30% of all IPMNs, revealing phenotpyes comparable with conventional ductal adenocarcinomas or mucinous (colloid) carcinomas of the pancreas. In Sendai-negative side-branch IPMNs, however, the annual risk of the development of invasive cancer is 2%; thus, risk stratification with regard to imaging and preoperative biomarkers and cytology is mandatory.

Methods and Results

The present study addresses the radiological and interventional preoperative measures including histological features to determine the risk of malignancy and the prognosis of IPMNs.

Conclusion

While preoperative imaging largely relies on the detection of macroscopic features of IPMNs, which are associated with a divergent risk of malignant behavior, in resected specimens the determination of the grade of dysplasia and the detection of an invasive component are the most important features to estimate the prognosis of IPMNs.

Endoscopic ultrasound and pancreatic cystic lesions-diagnostic and therapeutic applications

Pancreatic cystic lesions are being detected with an increasing frequency. Endoscopic ultrasound (EUS) provides both diagnostic and therapeutic means for pancreatic cystic lesions. Detailed imaging and EUS-guided fine-needle aspiration provide additional information on pancreatic cystic lesions. EUS-guided pseudocyst drainage has advantages over conventional drainage modalities. EUS-guided cyst ablation is a promising therapeutic modality.

Multiple recurrent pancreatic cysts with associated pancreatic inflammation and atrophy in a cat

Previous reports of true pancreatic cysts in cats have suggested that pancreatic cysts in cats are benign incidental findings. This case report describes the progressive clinical course and diagnostic findings in a cat with multiple recurrent pancreatic cysts. The presenting clinical signs included diarrhea, intermittent vomiting, polyphagia, and marked weight loss. Pancreatic cysts were identified via abdominal ultrasound and computed tomography (CT). An exploratory celiotomy and lesion histopathology confirmed multiple true pancreatic cysts of unknown etiology. One month after surgery the cat presented for lethargy and decreased appetite. Clinical re-evaluation was diagnostic for diabetes mellitus and an abdominal ultrasound confirmed recurrence of the pancreatic cysts. The recurrent nature of the pancreatic cysts and the concurrent development of diabetes mellitus were suggestive of progressive loss of pancreatic function or insulin resistance. This is the first described case of multiple recurring pancreatic cysts in a cat associated with pancreatic inflammation, atrophy and endocrine dysfunction.

Serous microcystic adenoma of the pancreatic head: Report of two cases and review of the literature

Serous microcystic adenomas (SMAs), also known as glycogen-rich cystadenomas, are uncommon exocrine tumors mainly involved in the body and tail of the pancreas. In this study, we report two SMA cases of the pancreatic head. In case 1, a 47-year-old woman was referred to our hospital for abdominal bloating and back pain; in case 2, a pancreatic space-occupying lesion was incidentally discovered in an asymptomatic 71-year-old female during an ultrasound. In both cases, a computer tomography scan showed well-demarcated and multilocular cysts in the head of the pancreas, and a central scar and calcifications were noted in case 1. During the exploratory laparotomies, the multiple cystic masses were found in the pancreatic head. A segmental resection of the pancreas and pancreatic jejunal anastomosis were performed. Histologically, the tumors were composed of tiny cysts that were filled with clear fluid and lined by a single layer of cuboidal cells with round, centrally located nuclei and clear cytoplasm, without cellular atypia. Immunohistochemical studies showed that the neoplastic cells were positive for cytokeratin 7 and vimentin but negative for synaptophysin and cytokeratin 20. A postoperative follow-up indicated no recurrence in the patients. We reviewed the literature regarding the etiology, clinical presentation, imaging characteristics, features and management of this lesion.

Pancreatic cystic neoplasms

Cystic neoplasms of the pancreas have been recognized for almost 2 centuries, but the principles of management continue to evolve. Clinicians have a better understanding now of the diverse pathologies and behaviors of cystic neoplasms, and can characterize them more precisely into benign, malignant, and of uncertain potential in their manifestations. Treatment is dependent on accurate diagnosis and tailored to the potential aggressiveness of the lesion, the surgical fitness of the patient, and the probability of effecting long-term palliation or survival of the patient. In this article the authors review the classification based on the World Health Organization classification and the latest evidence-based literature of cystic neoplasms, and present their considerations for surgical management of the various lesions. A better understanding of the biologic potential of cystic neoplasms such as intraductal papillary mucinous neoplasms allows for a more patient-specific evidence-based management plan.

Survey of the management of pancreatic pseudocysts in Sweden

OBJECTIVE

The management of pancreatic pseudocysts varies, based mainly on local traditions, resources and expertise. No prospective, randomized study has been done comparing different approaches to treatment. The aim of the present study was to identify current treatment strategies in Sweden.

MATERIAL AND METHODS

A questionnaire comprising 12 questions was e-mailed to the surgical departments of all hospitals (n=58) treating patients with pancreatitis. Comparisons were made between university and non-university hospitals and between hospitals with 150,000 or more persons versus less in the primary catchment area.

RESULTS

Fifty-one hospitals responded (88%). In median, 4 (0-25) patients were treated yearly due to pancreatic pseudocysts at each hospital. Five hospitals had written guidelines. Multidisciplinary team conferences were held at 36/48 centres. Treatment strategies for acute compared to chronic pancreatitis associated pseudocysts differed significantly depending on the underlying diagnosis in the major hospitals (p=0.005). Overall, 21/49 hospitals refer some of these patients and 15/50 of the departments state that they regularly assist in taking care of patients with pancreatic pseudocysts from other hospitals. The chosen treatment modalities vary widely, above all concerning endoscopic drainage, which is more common for symptomatic non-infected pseudocysts (p=0.005) as well as infected pseudocysts (p=0.004) in university hospitals.

CONCLUSIONS

The lack of protocols and management strategies for pancreatic pseudocysts is reflected by the heterogeneity in treatment strategies, as seen in the present survey. Therefore patients may be at risk of receiving suboptimal treatment. A tailored therapeutic approach that takes into consideration patient preferences and involves a multidisciplinary team should be considered in all cases.