Pancreatic cystic neoplasms: a review of preoperative diagnosis and management

Surgical outcomes of resected cystic neoplasms of pancreas: Experience from a tertiary care centre in India

Objectives

Cystic neoplasms of the pancreas form a rare heterogeneous group of pancreatic tumors with variable clinical and diagnostic characteristics. Its incidence has increased in recent years due to improvements in cross-sectional imaging methods and awareness amongst surgeons.

Material and Methods

This study aimed to study the demographic, clinical, imaging, and histopathologic characteristics, incidence of malignancy and outcome of surgical resection of pancreatic cystic neoplasms. Retrospective analysis of 91 patients who underwent surgical resection for cystic neoplasm of the pancreas between 2006 to 2017 at a tertiary care institute was done.

Results

There was a female preponderance in the study with a mean age of 47.2 years. Abdominal pain (46.1%) and jaundice (23.1%) were the most common symptoms. Computed tomography and endoultrasound (EUS) were the most commonly used imaging methods in the study and demonstrated good surgical correlation. Pancreaticoduodenectomy (37.1%) was the most commonly performed procedure followed by distal pancreaticosplenectomy (31.8%). Of the lesions, 9.8% were found malignant. Solid pseudopapillary epithelial neoplasm (SPEN) (37.3%) was the most common neoplasm followed by serous (21.9%), intraductal papillary mucinous neoplasm (IPMN) (15.3%) and mucinous neoplasm (14.3%). Preoperative radiological diagnostic correlation was found to be 75-100% implying the importance of imaging in cystic neoplasms of the pancreas. Morbidity and mortality in the study group were 28.5% and 2.1%, respectively.

Conclusion

Pancreatic cystic neoplasms were mostly benign with female preponderance and presented in the younger age group with prevalence of SPEN higher than IPMN in our subcontinent. These can be reliably diagnosed on preoperative cross-sectional imaging, and surgical resection is associated with favourable outcome and acceptable morbidity.

Cystic Neoplasms of the Pancreas: Differential Diagnosis and Radiology Correlation

Although the probability of pancreatic cystic neoplasms (PCNs) being detected is raising year by year, their differential diagnosis and individualized treatment are still a challenge in clinical work. PCNs are tumors containing cystic components with different biological behaviors, and their clinical manifestations, epidemiology, imaging features, and malignant risks are different. Some are benign [e.g., serous cystic neoplasms (SCNs)], with a barely possible that turning into malignant, while others display a low or higher malignant risk [e.g., solid pseudopapillary neoplasms (SPNs), intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms (MCNs)]. PCN management should concentrate on preventing the progression of malignant tumors while preventing complications caused by unnecessary surgical intervention. Clinically, various advanced imaging equipment are usually combined to obtain a more reliable preoperative diagnosis. The challenge for clinicians and radiologists is how to accurately diagnose PCNs before surgery so that corresponding surgical methods and follow-up strategies can be developed or not, as appropriate. The objective of this review is to sum up the clinical features, imaging findings and management of the most common PCNs according to the classic literature and latest guidelines.

Application of CT-Based Radiomics in Discriminating Pancreatic Cystadenomas From Pancreatic Neuroendocrine Tumors Using Machine Learning Methods

Objectives

The purpose of this study aimed at investigating the reliability of radiomics features extracted from contrast-enhanced CT in differentiating pancreatic cystadenomas from pancreatic neuroendocrine tumors (PNETs) using machine-learning methods.

Methods

In this study, a total number of 120 patients, including 66 pancreatic cystadenomas patients and 54 PNETs patients were enrolled. Forty-eight radiomic features were extracted from contrast-enhanced CT images using LIFEx software. Five feature selection methods were adopted to determine the appropriate features for classifiers. Then, nine machine learning classifiers were employed to build predictive models. The performance of the forty-five models was evaluated with area under the curve (AUC), accuracy, sensitivity, specificity, and F1 score in the testing group.

Results

The predictive models exhibited reliable ability of differentiating pancreatic cystadenomas from PNETs when combined with suitable selection methods. A combination of DC as the selection method and RF as the classifier, as well as Xgboost+RF, demonstrated the best discriminative ability, with the highest AUC of 0.997 in the testing group.

Conclusions

Radiomics-based machine learning methods might be a noninvasive tool to assist in differentiating pancreatic cystadenomas and PNETs.

Benign macrocystic serous cystadenoma of the pancreas

Serous cystadenoma is a rare benign cystic lesion of pancreas. They are mostly known as benign cystic tumors of pancreas but malign transformation as serous cystadenocarcinoma is also reported. It is more commonly observed in women with the mean age of onset is 62 years. The majority of patients present nonspecific symptoms such as abdominal pain, weight loss, nausea, vomiting, fever, and melena. One-third of the patients are asymptomatic. A 60-year-old woman presents with abdominal pain and nausea for 1 month was admitted. Physical and laboratory findings were normal. Abdomen computed tomography scan confirmed a large number of millimetric cysts of 45 × 47 × 50 mm in size at the head of the pancreas. Due to patient's symptoms and mass effect, Whipple procedure was performed. In the gross examination, a nodular area of 5 × 5 × 4 cm was observed in the head of the pancreas. The microscopic examination of the material revealed cystic structures with fibrous stroma dotted with single layered cuboidal epithelium in the pancreatic tissue. The pathology report confirmed benign macrocystic serous cystadenoma. Serous cystadenomas are rare benign cystic lesions of the pancreas. Although they are benign lesions, it is crucial to differentiate them from other cystic lesions of the pancreas and malignant serous cystadenocarcinomas.

Patients with pancreatic cystic neoplasms can benefit from management of multidisciplinary team: Experience from a Chinese academic center

BACKGROUND

Pancreatic cystic neoplasms (PCNs) are a spectrum of neoplasms that can be benign or malignant. The accuracy of diagnosis is critical for this disease since different types of PCNs are treated differently using various modalities. The use of a multidisciplinary team (MDT) has been shown to improve the management and outcomes of various diseases. We aimed to determine the performance of MDT in the management of PCNs.

METHODS

We retrospectively reviewed 167 pathologically-proven PCN patients and divided them among three groups according to their surgical data and treatment modalities: 1) historical control group (HC group); 2) concurrent control group (CC group); and 3) MDT group. The composition of subtypes of PCNs, preoperative diagnostic accuracy, postoperative complications, and postoperative hospital stay were compared among the three groups.

RESULTS

The incidence of SCN reduced in the MDT group, while the incidence of IPMN was much higher (P < 0.05). MDT management significantly improved the accuracy of preoperative diagnosis (71.7%) and also increased the individual diagnostic accuracies of ultrasound, CT, and MRI/MRCP. Postoperative pancreatic fistula was significantly reduced in the MDT group (28.3%; P < 0.001). Furthermore, the mean hospital stay after surgery in the MDT group (10.37 days) was shorter than those of the other two groups (27.35 days in HC group, and 19.28 days in CC group; P < 0.05).

CONCLUSION

For patients with PCN, MDT management was associated with an improvement in the overall accuracy of preoperative diagnosis, a lower incidence postoperative morbidity, and decreased length of hospital stay.

A new combined criterion to better predict malignant lesions in patients with pancreatic cystic neoplasms

Objective:

Cystic lesions of the pancreas have been increasingly recognized. Some lesions exhibit benign behavior, while others have unequivocal malignant potential. Thus, accurate identification of malignancy in patients diagnosed with pancreatic cystic neoplasms (PCNs) remains a major challenge. The aim of this study was to define a combined criterion to better predict malignant lesions in patients with PCNs.

Methods:

We retrospectively analyzed 165 patients who underwent resection of PCNs from October 2011 to May 2017. The relationship among malignancy and serum carbohydrate antigen 19-9 (CA19-9), preoperative neutrophil-to-lymphocyte ratio (NLR), and the presence of enhanced solid component on imaging was analyzed.

Results:

NLR before surgery in patients with malignant PCNs (2.81±2.14) was significantly higher than that in patients diagnosed with pancreatic neuroendocrine tumor (1.90±0.69, P=0.013) or healthy volunteers (1.40±0.48; P<0.001). Serum CA19-9 ≥39 U/mL, NLR >1.976 and presence of enhanced solid component were independent predictors of PCN malignancy. A combined criterion meeting any two or more of the three elements including CA19-9 ≥39 U/mL, NLR >1.976, and presence of enhanced solid component on computed tomography imaging is an indicator with a high positive predictive value of 80.5% and a high negative predictive value of 87.9%, and thus, represents a highly accurate test (86.1%).

Conclusions:

The new combined criterion is an effective predictor of tumor malignancy in patients with PCNs.

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.

Diagnosis and management of cystic lesions of the pancreas

Pancreatic cystic lesions (PCLs) are being increasingly identified in recent years. They show a wide spectrum of imaging and clinical features. The diagnosis and discrimination of these lesions are very important because of the risk for concurrent or later development of malignancy. PCLs are usually first diagnosed and characterized by conventional imaging modalities such as trans-abdominal ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI). However, their ability to differentiate the benign and malignant lesions remains limited. Endoscopic US may be more helpful for the diagnosis and differentiation of PCLs because of its high resolution and better imaging characteristics than cross-sectional imaging modalities. It also allows for fine-needle aspiration (FNA) of cystic lesions for biochemical, cytological and DNA analysis that might be further helpful for diagnosis and differentiation. The management options of PCLs are to observe, endoscopic treatment or surgical resection. However, the decision for management is sometimes hampered by limitations in current diagnostic and tissue sampling techniques. As further diagnostic and non-invasive management options become available, clinical decision-making will become much easier for these lesions.

Pancreatic cystic neoplasms

Background:

Cystic neoplasms of the pancreas are rare and constitute approximately 0.5% of all pancreatic neoplasms.

Aims:

The study was to describe clinicopathological features of pancreatic cystic tumors.

Patients and Methods:

In our retrospective study, we reviewed 10 cases of pancreatic cystic neoplasms that were diagnosed at the pathology department of Mongi Slim hospital over a 14-year period (2000-2013). We adopted the latest World Health Organization (WHO) classification (2010) in grouping all tumors.

Results:

There were one male and nine female patients (sex ratio M/F = 1:9) aged between 21 and 68 years (mean = 37.5 years). The most common clinical presentation was epigastric and abdominal pain (n = 6) followed by vomiting (n = 3). Abdominal computed tomography (CT) scan disclosed a cystic lesion of the pancreas ranging in size between 2 and 10 cm (mean = 6.75 cm). All patients underwent surgical treatment. Histopathological examination of the surgical specimen established the diagnosis of solid pseudopapillary neoplasm (n = 2), serous cystic neoplasm (n = 2), mucinous cystadenoma (n = 4), mucinous cystadenocarcinoma (n = 1), and intraductal papillary mucinous neoplasm with invasive carcinoma (n = 1).

Conclusion:

Better understanding of pancreatic cystic neoplasms is essential for clinicians to make accurate diagnosis and to provide the best management for patients.

Surgical resection and outcome of pancreatic cystic neoplasms in China: analysis of a 16-year experience from a single high-volume academic institution

Background

To investigate the clinicopathological features of surgically resected pancreatic cystic neoplasms (PCNs) at a single institution in China.

Methods

The medical charts of patients who operated in the Second Affiliated Hospital, Zhejiang University School of Medicine between 1 January 1997 and 30 June 2013, were pathologically shown to have PCNs.

Results

There was a reliable increase trend not just in the overall number of patients (3 to 75) but additionally in the number of incidentally diagnosed patients across the periods (33.3% to 48.0%). In 83 of 111 cases, preoperative diagnoses matched with pathology, whereas the remaining cases (16/28) were misdiagnosed as pancreatic cancer. The proportion of malignancy in mucin producing neoplasms was 24.3% (9 out of 37). Elevated serum carbohydrate antigen (CA19-9) or carcinoembryonic antigen (CEA) was independently associated with malignancy. The overall survival rate was 96.4%.

Conclusions

The proportion of PCNs within this series differs with that revealed in Western countries. Appropriate preoperative differential diagnosing of PCNs remains challenging. It is strongly recommended that patients with elevated CA19-9 or CEA levels undergo surgical resection.