American Gastroenterological Association guidelines are inaccurate in detecting pancreatic cysts with advanced neoplasia: a clinicopathologic study of 225 patients with supporting molecular data

Echoendoscopic ultrasound pancreatic adenocarcinoma diagnosis and theranostic approach: should KRAS mutation research be recommended in everyday practice?

Background

The impact of KRAS mutation testing on pancreatic ductal adenocarcinoma (PDAC) samples by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for reducing the need to repeat EUS-FNA has been demonstrated. Such testing however is not part of standard practice for endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB).

Objectives

We aim to analyse the proportion of non-contributive samples by EUS-FNB and to evaluate the impact of KRAS mutation testing on the diagnosis, theranostics and survival.

Design

In this retrospective study, the impact on diagnosis and survival of KRAS testing for contributive and non-contributive samples by EUS-FNB was analysed.

Methods

The EUS-FNB samples, combined with KRAS testing using the Idylla® technique on liquid-based cytology from patients with PDAC between February 2019 and May 2023, were retrospectively reviewed. The cytology results were classified according to the guidelines of the World Health Organization System for Reporting Pancreaticobiliary Cytopathology (WHOSRPC).

Results

A total of 85 EUS-FNB specimens were reviewed. In all, 25 EUS-FNB samples did not lead to a formal diagnosis of PDAC according to the WHOSRPC (30.2%). Out of these 25, 11 (44%) could have been considered positive for a PDAC diagnosis thanks to the KRAS mutation test without carrying out further diagnosis procedures. The sensitivity of KRAS mutation testing using the Idylla technique was 98.6%. According to the available data, survival rates were not statistically different depending on the type of mutation.

Conclusion

KRAS mutation testing on liquid-based cytology using the Idylla or equivalent technique, combined with the PDAC EUS-FNB sample, should become a standard for diagnosis to avoid delaying treatment by doing another biopsy. Furthermore, knowledge of the KRAS status from treatment initiation could be used to isolate mutations requiring targeted treatments or inclusion in clinical research trials, especially for wild-type KRAS PDAC.

Endoscopic Interventions in Pancreatic Cystic Neoplasms

During the past two decades, there has been a significant evolution in endoscopic interventions in pancreatic cystic neoplasms (PCNs), ranging from diagnostic intervention (endoscopic ultrasound-guided through-the-needle biopsy [EUS-TTNB]) to therapeutic intervention (endoscopic ultrasound-guided pancreatic cystic ablation [EUS-PCA]). They have received attention as alternatives to conventional diagnostic and therapeutic modalities. EUS-TTNB can categorize PCN types accurately by providing histologic diagnoses that conventional diagnostic modalities cannot provide. As pancreatectomy entails high morbidities, EUS-PCA can be performed safely to treat PCNs in patients who refuse surgery or have high surgical risks.

A Combined DNA/RNA-based Next-Generation Sequencing Platform to Improve the Classification of Pancreatic Cysts and Early Detection of Pancreatic Cancer Arising From Pancreatic Cysts

OBJECTIVE

We report the development and validation of a combined DNA/RNA next-generation sequencing (NGS) platform to improve the evaluation of pancreatic cysts.

BACKGROUND AND AIMS

Despite a multidisciplinary approach, pancreatic cyst classification, such as a cystic precursor neoplasm, and the detection of high-grade dysplasia and early adenocarcinoma (advanced neoplasia) can be challenging. NGS of preoperative pancreatic cyst fluid improves the clinical evaluation of pancreatic cysts, but the recent identification of novel genomic alterations necessitates the creation of a comprehensive panel and the development of a genomic classifier to integrate the complex molecular results.

METHODS

An updated and unique 74-gene DNA/RNA-targeted NGS panel (PancreaSeq Genomic Classifier) was created to evaluate 5 classes of genomic alterations to include gene mutations (e.g., KRAS, GNAS, etc.), gene fusions and gene expression. Further, CEA mRNA ( CEACAM5 ) was integrated into the assay using RT-qPCR. Separate multi-institutional cohorts for training (n=108) and validation (n=77) were tested, and diagnostic performance was compared to clinical, imaging, cytopathologic, and guideline data.

RESULTS

Upon creation of a genomic classifier system, PancreaSeq GC yielded a 95% sensitivity and 100% specificity for a cystic precursor neoplasm, and the sensitivity and specificity for advanced neoplasia were 82% and 100%, respectively. Associated symptoms, cyst size, duct dilatation, a mural nodule, increasing cyst size, and malignant cytopathology had lower sensitivities (41-59%) and lower specificities (56-96%) for advanced neoplasia. This test also increased the sensitivity of current pancreatic cyst guidelines (IAP/Fukuoka and AGA) by >10% and maintained their inherent specificity.

CONCLUSIONS

PancreaSeq GC was not only accurate in predicting pancreatic cyst type and advanced neoplasia but also improved the sensitivity of current pancreatic cyst guidelines.

Simultaneous and sequential combination of genetic and epigenetic biomarkers for the presence of high-grade dysplasia in patients with pancreatic cyst: Discovery in cyst fluid and test in pancreatic juice

BACKGROUND/OBJECTIVES

Screening patients with intraductal papillary mucinous neoplasms (IPMN) has the primary goal of identifying potentially curable noninvasive precursors. We aimed to evaluate the diagnostic impact of genetic and epigenetic biomarkers in the presence of noninvasive precursors.

METHODS

Mutated KRAS/GNAS and methylated SOX17/TBX15/BMP3/TFPI2 DNA were assessed by droplet digital PCR in a discovery cohort of 70 surgically aspirated cyst fluids, and diagnostic performances for differentiating high-grade dysplasia (HGD) from low-grade dysplasia (LGD) was evaluated. We then tested these markers using an independent test cohort consisting of 156 serially collected pancreatic juice samples from 30 patients with IPMN.

RESULTS

Mutated KRAS and GNAS are specific for IPMNs but are not helpful for the prediction of histological grades. Cyst fluids from IPMN with HGD showed higher methylation levels of SOX17 (median, 0.141 vs. 0.021; P = 0.086) and TBX15 (median, 0.030 vs. 0.003; P = 0.028) than those with LGD. The combination of all tested markers yielded a diagnostic performance with sensitivity of 69.6%, and specificity of 90.0%. Among the 30 pancreatic juice samples exhibiting the highest abundance of KRAS/GNAS mutations in each patient in the test cohort, patients with histologically proven HGD due to pancreatic resection had a significantly higher prevalence (100% vs. 31%, P = 0.018) and abundance (P = 0.037) of methylated TBX15 than those without cytohistological diagnosis undergoing surveillance.

CONCLUSIONS

A simultaneous and sequential combination of mutated and methylated DNA markers in pancreatic cyst fluid and juice sample markers can help detect noninvasive pancreatic precursor neoplasms.

Pancreatic Cystic Neoplasms: Translating Guidelines into Clinical Practice

A combination of several factors, including the increasing use of cross-sectional imaging and an aging population, has led to pancreatic cystic lesions (PCLs) becoming the most detected incidental pancreatic lesions. Accurate diagnosis and risk stratification of PCLs is challenging. In the last decade, several evidence-based guidelines have been published addressing the diagnosis and management of PCLs. However, these guidelines cover different subsets of patients with PCLs and offer varying recommendations regarding diagnostic assessment, surveillance, and surgical resection. Further, recent studies comparing the accuracy of various guidelines have reported significant variations in the rate of missed cancer versus unnecessary surgical resections. In clinical practice, it is challenging to decide which guideline to follow specifically. This article reviews the varying recommendations of the major guidelines and results of comparative studies, provides an overview of newer modalities not included in the guidelines, and offers perspectives on translating the guidelines into clinical practice.

Diagnostic accuracy of the AGA, IAP, and European guidelines for detecting advanced neoplasia in intraductal papillary mucinous neoplasm/neoplasia

BACKGROUND

Follow-up in patients with intraductal papillary mucinous neoplasm (IPMN) aims to detect advanced neoplasia (high-grade dysplasia/cancer) in an early stage. The 2015 American Gastroenterological Association (AGA), 2017 International Association of Pancreatology (IAP), and the 2018 European Study Group on Cystic tumours of the Pancreas (European) guidelines differ in their recommendations on indications for surgery. However, it remains unclear which guideline is most accurate in predicting advanced neoplasia in IPMN.

METHODS

Patients who underwent surgery were extracted from a prospective database (January 2006-January 2021). In patients with IPMN, final pathology was compared with the indication for surgery according to the guidelines. ROC-curves were calculated to determine the diagnostic accuracy for each guideline.

RESULTS

Overall, 247 patients underwent surgery for cystic lesions. In 145 patients with IPMN, 52 had advanced neoplasia, of which the AGA guideline would have advised surgery in 14 (27%), the IAP and European guideline in 49 (94%) and 50 (96%). In 93 patients without advanced neoplasia, the AGA, IAP, and European guidelines would incorrectly have advised surgery in 8 (8.6%), 77 (83%) and 71 (76%).

CONCLUSION

The European and IAP guidelines are clearly superior in detecting advanced neoplasia in IPMN as compared to the AGA, albeit at the cost of a higher rate of unnecessary surgery. To harmonize care and to avoid confusion caused by conflicting statements, a global evidence-based guideline for PCN in collaboration with the various guidelines groups is required once the current guidelines require an update.

Prospective, Multi-Institutional, Real-Time Next-Generation Sequencing of Pancreatic Cyst Fluid Reveals Diverse Genomic Alterations That Improve the Clinical Management of Pancreatic Cysts

BACKGROUND & AIMS

Next-generation sequencing (NGS) of pancreatic cyst fluid is a useful adjunct in the assessment of patients with pancreatic cyst. However, previous studies have been retrospective or single institutional experiences. The aim of this study was to prospectively evaluate NGS on a multi-institutional cohort of patients with pancreatic cyst in real time.

METHODS

The performance of a 22-gene NGS panel (PancreaSeq) was first retrospectively confirmed and then within a 2-year timeframe, PancreaSeq testing was prospectively used to evaluate endoscopic ultrasound-guided fine-needle aspiration pancreatic cyst fluid from 31 institutions. PancreaSeq results were correlated with endoscopic ultrasound findings, ancillary studies, current pancreatic cyst guidelines, follow-up, and expanded testing (Oncomine) of postoperative specimens.

RESULTS

Among 1933 PCs prospectively tested, 1887 (98%) specimens from 1832 patients were satisfactory for PancreaSeq testing. Follow-up was available for 1216 (66%) patients (median, 23 months). Based on 251 (21%) patients with surgical pathology, mitogen-activated protein kinase/GNAS mutations had 90% sensitivity and 100% specificity for a mucinous cyst (positive predictive value [PPV], 100%; negative predictive value [NPV], 77%). On exclusion of low-level variants, the combination of mitogen-activated protein kinase/GNAS and TP53/SMAD4/CTNNB1/mammalian target of rapamycin alterations had 88% sensitivity and 98% specificity for advanced neoplasia (PPV, 97%; NPV, 93%). Inclusion of cytopathologic evaluation to PancreaSeq testing improved the sensitivity to 93% and maintained a high specificity of 95% (PPV, 92%; NPV, 95%). In comparison, other modalities and current pancreatic cyst guidelines, such as the American Gastroenterology Association and International Association of Pancreatology/Fukuoka guidelines, show inferior diagnostic performance. The sensitivities and specificities of VHL and MEN1/loss of heterozygosity alterations were 71% and 100% for serous cystadenomas (PPV, 100%; NPV, 98%), and 68% and 98% for pancreatic neuroendocrine tumors (PPV, 85%; NPV, 95%), respectively. On follow-up, serous cystadenomas with TP53/TERT mutations exhibited interval growth, whereas pancreatic neuroendocrine tumors with loss of heterozygosity of ≥3 genes tended to have distant metastasis. None of the 965 patients who did not undergo surgery developed malignancy. Postoperative Oncomine testing identified mucinous cysts with BRAF fusions and ERBB2 amplification, and advanced neoplasia with CDKN2A alterations.

CONCLUSIONS

PancreaSeq was not only sensitive and specific for various pancreatic cyst types and advanced neoplasia arising from mucinous cysts, but also reveals the diversity of genomic alterations seen in pancreatic cysts and their clinical significance.

Molecular Analysis of Pancreatic Cyst Fluid for the Management of Intraductal Papillary Mucinous Neoplasms

Pancreatic cancer is one of the most lethal human cancers. Early detection and diagnosis of precursor lesions for pancreatic malignancy is essential to improve the morbidity and mortality associated with this diagnosis. Of the cystic precursor lesions, branch duct intraductal papillary mucinous neoplasm (IPMN) is the most frequently identified lesion and has a wide range of malignant potential. Currently, Carcinogenic embryonic antigen (CEA) levels in the cyst fluid and cytology are the two most often utilized tools to diagnose these lesions; however, their diagnostic and risk stratification capabilities are somewhat limited. Within the last decade, the use of endoscopic ultrasound-guided fine-needle aspiration has opened the door for molecular analysis of cystic fluid as an option to enhance both the diagnosis and risk stratification of these lesions. The first step is to differentiate branch duct IPMNs from other lesions. KRAS and GNAS alterations have been shown to be accurate markers for this purpose. Following cyst type identification, mutational analysis, telomere fusion, microRNAs, long non-coding RNA, and DNA methylation have been identified as potential targets for stratifying malignant potential using the cystic fluid. In this review, we will examine the various targets of cyst fluid molecular analysis and their utility in the diagnosis and risk stratification of branch duct IPMNs.

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.

Telomere Attrition in Intraductal Papillary Mucinous Neoplasms of the Pancreas Associated With Carcinogenesis and Aging

OBJECTIVES

It is challenging to preoperatively distinguish malignant and benign forms of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. The aims of this study were to investigate whether telomere length is associated with pathological grade of IPMNs and age and to clarify the utility of telomere length as a marker to identify malignant IPMNs.

METHODS

Pancreas tissue was obtained from 28 patients after resection. We measured the telomere lengths of tumor cells in IPMNs and normal duct cells by quantitative fluorescence in situ hybridization. The association of normalized telomere-centromere ratio (NTCR) to pathological grade of IPMNs and age were determined.

RESULTS

The NTCR showed a gradual decrease with increasing pathological grade of IPMNs. The NTCR in intermediate- and high-grade dysplasia and adenocarcinoma lesions was significantly shorter than in normal pancreatic ducts (P < 0.05). In multivariate analysis, telomere length was most associated with carcinogenesis. When the cutoff value of NTCR was set to 0.74, the sensitivity for detection of high-grade dysplasia and adenocarcinoma was 82.8%, with a specificity of 87.5%.

CONCLUSIONS

Telomere shortening occurs with carcinogenesis and aging. A significant reduction of telomere length in IPMNs may be useful for surgical decision making.

State-of-the-Art Update of Pancreatic Cysts

Andrew Canakis.

Pancreatic CT density is an optimal imaging biomarker for earlier detection of malignancy in the pancreas with intraductal papillary mucinous neoplasm

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are typically detected as incidental findings by computed tomography (CT); however, the conventional surveillance is not valid for the early detection of concomitant pancreatic cancer. The pancreas of IPMN is often accompanied by fatty infiltration in the parenchyma, and pancreatic fatty infiltration could be evaluated by pancreatic CT density (pancreatic index, PI). We aimed to investigate whether PI could be an imaging biomarker for the early prediction of malignancies in the pancreas with IPMN.

METHODS

Two different cohorts were investigated. (Investigation cohort): A total of 1137 patients with initially low-risk IPMN were compensated by initial IPMN findings, and 2 groups (malignancy/possible benign, 50 cases each) were investigated for yearly changes in PI and for the cutoff value of PI indicating the development of malignancies. (Validation cohort): To validate the cutoff value, 256 patients radiologically suspected of having IPMNs were investigated.

RESULTS

(Investigation-cohort): The malignancy group showed a gradual decrease in PI every year, and PI significantly differed among the 2 groups 1 year prior to the last investigation. The cutoff value of PI was set at 0.65. (Validation-cohort): A total of 55% of the patients with a PI below the cutoff value had malignancy in the pancreas, including concomitant pancreatic cancer, and the cutoff value was the most significant risk factors for the development of malignancies in the pancreas compared to the conventional risk factors for IPMN.

CONCLUSIONS

Decreasing PI would be an optimal imaging biomarker for earlier detection of malignancies in the pancreas with IPMN.

Efficacy and safety of EUS-guided through-the-needle microforceps biopsy sampling in categorizing the type of pancreatic cystic lesions

BACKGROUND AND AIMS

EUS-guided through-the-needle biopsy sampling (EUS-TTNB) using microbiopsy forceps is performed for the accurate diagnosis of pancreatic cystic lesions (PCLs). However, there are no standardized protocols for this procedure, and the amount of data on its efficacy is limited. Here, we evaluated the feasibility, efficacy, and safety of EUS-TTNB in categorizing the types of PCLs and identified the factors associated with diagnostic failure.

METHODS

The prospectively collected and maintained EUS-TTNB database at Asan Medical Center was reviewed to identify patients with PCLs who underwent EUS-TTNB between January 2019 and January 2021. The primary outcomes were technical success, diagnostic yield, and adverse events. Factors contributing to diagnostic failure and the discrepancies in the diagnosis made by conventional modalities (ie, EUS morphology, cross-sectional imaging, and cystic fluid analysis) were also evaluated.

RESULTS

Forty-five patients were analyzed. EUS-TTNB was successfully performed in all patients (technical success, 100%). Histologic diagnosis of PCLs was made in 37 patients (diagnostic yield, 82%). When comparing EUS-TTNB with a presumptive diagnosis, EUS-TTNB changed the diagnosis in 10 patients in terms of the categorization of the types of PCLs. The diagnostic yield was significantly higher in those who had 4 or more visible biopsy specimens per session (93%) than in those with fewer than 4 visible biopsy specimens per session (67%; P = .045). During follow-up, 3 patients (7%) experienced adverse events (2 acute pancreatitis, 1 intracystic bleeding), and no life-threatening adverse event occurred.

CONCLUSIONS

EUS-TTNB showed high technical feasibility, diagnostic yield, and good safety profile. EUS-TTNB may improve the categorization of the types of PCLs. Studies with standardized procedure protocols are needed to reduce the diagnostic failure for the types of PCLs.

Updates in diagnosis and management of pancreatic cysts

Incidental pancreatic cysts are commonly encountered with some cysts having malignant potential. The most common pancreatic cystic neoplasms include serous cystadenoma, mucinous cystic neoplasm and intraductal papillary mucinous neoplasm. Risk stratifying pancreatic cysts is important in deciding whether patients may benefit from endoscopic ultrasound (EUS) or surgical resection. Surgery should be reserved for patients with malignant cysts or cysts at high risk for developing malignancy as suggested by various risk features including solid mass, nodule and dilated main pancreatic duct. EUS may supplement magnetic resonance imaging findings for cysts that remain indeterminate or have concerning features on imaging. Various cyst fluid markers including carcinoembryonic antigen, glucose, amylase, cytology, and DNA markers help distinguish mucinous from nonmucinous cysts. This review will guide the practicing gastroenterologist in how to evaluate incidental pancreatic cysts and when to consider referral for EUS or surgery. For presumed low risk cysts, surveillance strategies will be discussed. Managing pancreatic cysts requires an individualized approach that is directed by the various guidelines.

Comparing accuracy of high-risk features for detecting advanced neoplasia in pancreatic cystic lesions: a systematic review and meta-analysis

Background

The American Gastroenterological Association recommends endoscopic ultrasound (EUS) for evaluating pancreatic cystic lesions (PCL) with ≥2 high-risk features (HRF), whereas the American College of Gastroenterology recommends EUS for ≥1 HRF. This systematic review and meta-analysis compared the diagnostic accuracy of using ≥1 vs. ≥2 HRF for assessing the risk of advanced neoplasia (AN) and performing EUS in PCL.

Methods

An electronic database search was performed for eligible studies. AN was defined as pancreatic adenocarcinoma, intraductal papillary mucinous neoplasm or mucinous cystadenoma with high-grade dysplasia, pancreatic intraepithelial neoplasia and pancreatic neuroendocrine tumors. HRF included cyst size ≥3 cm, solid component, and dilated pancreatic duct ≥5 mm. The primary outcome was the sensitivity and specificity of using ≥1 vs. ≥2 HRF as an indication for EUS to detect AN in PCL.

Results

Of 38 studies initially screened, 8 were included in the final analysis. Seven studies assessed the accuracy of ≥2 HRF and 4 studies assessed ≥1 HRF. The pooled sensitivity, specificity, positive and negative predictive values of EUS for detecting AN were 41.7% (95% confidence interval 19.5-67.8%), 90.8% (81.9-95.5%), 30.4% (19.4-44.2%) and 94.3% (89.6-97.0%) with ≥2HRFs, and 77.1% (66.1-85.3%), 72.7% (50.4-87.5%), 17.95% (10.3-29.4%), 98.1% (90.8-99.6%), respectively, with ≥1 HRF.

Conclusion

Performing EUS for PCL with ≥1 HRF could offer greater sensitivity in detecting AN compared to ≥2 HRF, with a similar negative predictive value.

Pancreatic cystic neoplasms: a review of current recommendations for surveillance and management

Pancreatic cystic neoplasms (PCN) comprise of a diverse array of pancreatic cysts, including intraductal papillary mucinous neoplasms (IPMN), mucinous cystic neoplasms (MCN), serous cystic neoplasms (SCN), cystic neuroendocrine tumors (cNET), and many others. Increasing use of cross-sectional imaging has resulted in greater numbers of PCNs discovered incidentally. The overall risk of malignancy is low, but can vary considerably between different classes of PCNs. Furthermore, many pancreatic cysts are indeterminate on imaging, and the inability to reliably predict the course of disease remains a challenge for radiologists. Due to the variability in disease course and a lack of high-quality studies on PCNs, there is no universal consensus when it comes to balancing optimal surveillance while avoiding the risk for overtreatment. Currently, there are three widely accepted international guidelines outlining guidelines for surveillance and management of PCNs: the American Gastroenterological Association (AGA) in 2015, the International Association of Pancreatology (IAP) last revised in 2017, and the European Study Group on Cystic Tumours of the Pancreas (European) last revised in 2018. In 2017, the American College of Radiology released its own comprehensive set of recommendations for managing indeterminate pancreatic cysts that are detected incidentally on CT or MRI. The purpose of this paper is to describe the key differences between the ACR recommendations and the aforementioned three sets of guidelines regarding cyst management, imaging surveillance, performance, and cost-effectiveness.

High performance in risk stratification of intraductal papillary mucinous neoplasms by confocal laser endomicroscopy image analysis with convolutional neural networks (with video)

BACKGROUND AND AIMS

EUS-guided needle-based confocal laser endomicroscopy (EUS-nCLE) can differentiate high-grade dysplasia/adenocarcinoma (HGD-Ca) in intraductal papillary mucinous neoplasms (IPMNs) but requires manual interpretation. We sought to derive predictive computer-aided diagnosis (CAD) and artificial intelligence (AI) algorithms to facilitate accurate diagnosis and risk stratification of IPMNs.

METHODS

A post hoc analysis of a single-center prospective study evaluating EUS-nCLE (2015-2019; INDEX study) was conducted using 15,027 video frames from 35 consecutive patients with histopathologically proven IPMNs (18 with HGD-Ca). We designed 2 CAD-convolutional neural network (CNN) algorithms: (1) a guided segmentation-based model (SBM), where the CNN-AI system was trained to detect and measure papillary epithelial thickness and darkness (indicative of cellular and nuclear stratification), and (2) a reasonably agnostic holistic-based model (HBM) where the CNN-AI system automatically extracted nCLE features for risk stratification. For the detection of HGD-Ca in IPMNs, the diagnostic performance of the CNN-CAD algorithms was compared with that of the American Gastroenterological Association (AGA) and revised Fukuoka guidelines.

RESULTS

Compared with the guidelines, both n-CLE-guided CNN-CAD algorithms yielded higher sensitivity (HBM, 83.3%; SBM, 83.3%; AGA, 55.6%; Fukuoka, 55.6%) and accuracy (SBM, 82.9%; HBM, 85.7%; AGA, 68.6%; Fukuoka, 74.3%) for diagnosing HGD-Ca, with comparable specificity (SBM, 82.4%; HBM, 88.2%; AGA, 82.4%; Fukuoka, 94.1%). Both CNN-CAD algorithms, the guided (SBM) and agnostic (HBM) models, were comparable in risk stratifying IPMNs.

CONCLUSION

EUS-nCLE-based CNN-CAD algorithms can accurately risk stratify IPMNs. Future multicenter validation studies and AI model improvements could enhance the accuracy and fully automatize the process for real-time interpretation.

Early detection of pancreatic cancer using DNA-based molecular approaches

Due to its poor prognosis and the late stage at which it is typically diagnosed, early detection of pancreatic cancer is a pressing clinical problem. Advances in genomic analysis of human pancreatic tissue and other biospecimens such as pancreatic cyst fluid, pancreatic juice and blood have opened the possibility of DNA-based molecular approaches for early detection of pancreatic cancer. In this Review, we discuss and focus on the pathological and molecular features of precancerous lesions of the pancreas, including pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm and mucinous cystic neoplasm, which are target lesions of early detection approaches. We also discuss the most prevalent genetic alterations in these precancerous lesions, including somatic mutations in the oncogenes KRAS and GNAS as well as tumour suppressor genes CDKN2A, TP53 and SMAD4. We highlight the latest discoveries related to genetic heterogeneity and multifocal neoplasia in precancerous lesions. In addition, we review specific approaches, challenges and clinically available assays for early detection of pancreatic cancer using DNA-based molecular techniques. Although detection and risk stratification of precancerous pancreatic neoplasms are difficult problems, progress in this field highlights the promise of molecular approaches for improving survival of patients with this disease.

Guidelines on management of pancreatic cysts detected in high-risk individuals: An evaluation of the 2017 Fukuoka guidelines and the 2020 International Cancer of the Pancreas Screening (CAPS) consortium statements

BACKGROUND

Objectives: Pancreatic cysts are frequently detected in high-risk individuals (HRI) undergoing surveillance for pancreatic cancer. The International Cancer of the Pancreas Screening (CAPS) Consortium developed consensus recommendations for surgical resection of pancreatic cysts in HRI that are similar to the Fukuoka guidelines used for the management of sporadic cysts. We compared the performance characteristics of CAPS criteria for pancreatic cyst management in HRI with the Fukuoka guidelines originally designed for the management of cysts in non-HRI.

METHODS

Using prospectively collected data from CAPS studies, we determined for each patient with resected screen-detected cyst(s) whether Fukuoka guidelines or CAPS consensus statements would have recommended surgery. We compared sensitivity, specificity, PPV, NPV, and Receiver Operator Characteristics (ROC) curves of these guidelines at predicting the presence of high-grade dysplasia or invasive cancer in pancreatic cysts.

RESULTS

356/732 HRI had ≥ one pancreatic cyst detected; 24 had surgery for concerning cystic lesions. The sensitivity, specificity, PPV, and NPV for the Fukuoka criteria were 40%, 85%, 40%, and 85%, while those of the CAPS criteria were 60%, 85%, 50%, 89%, respectively. ROC curve analyses showed no significant difference between the Fukuoka and CAPS criteria.

CONCLUSIONS

In HRI, the CAPS and Fukuoka criteria are moderately specific, but not sufficiently sensitive for detecting advanced neoplasia in cystic lesions. New approaches are needed to guide the surgical management of cystic lesions in HRI.

A Review of the Diagnosis and Management of Premalignant Pancreatic Cystic Lesions

Pancreatic cystic lesions are an increasingly common clinical finding. They represent a heterogeneous group of lesions that include two of the three known precursors of pancreatic cancer, intraductal papillary mucinous neoplasms (IPMN) and mucinous cystic neoplasms (MCN). Given that approximately 8% of pancreatic cancers arise from these lesions, careful surveillance and timely surgery offers an opportunity for early curative resection in a disease with a dismal prognosis. This review summarizes the current evidence and guidelines for the diagnosis and management of IPMN/MCN. Current pre-operative diagnostic tests in pancreatic cysts are imperfect and a proportion of patients continue to undergo unnecessary surgical resection annually. Balancing cancer prevention while preventing surgical overtreatment, continues to be challenging when managing pancreatic cysts. Cyst fluid molecular markers, such as KRAS, GNAS, VHL, PIK3CA, SMAD4 and TP53, as well as emerging endoscopic technologies such as needle-based confocal laser endomicroscopy and through the needle microbiopsy forceps demonstrate improved diagnostic accuracy. Differences in management and areas of uncertainty between the guidelines are also discussed, including indications for surgery, surveillance protocols and if and when surveillance can be discontinued.

Educational Case: Pancreatic Cystic Disease: A Multimodal Diagnostic Approach to Determine Clinical Management

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040 . 1

Molecular analysis of pancreatic cystic neoplasm in routine clinical practice

BACKGROUND

Cystic pancreatic lesions consist of a wide variety of lesions that are becoming increasingly diagnosed with the growing use of imaging techniques. Of these, mucinous cysts are especially relevant due to their risk of malignancy. However, morphological findings are often suboptimal for their differentiation. Endoscopic ultrasound fine-needle aspiration (EUS-FNA) with molecular analysis has been suggested to improve the diagnosis of pancreatic cysts.

AIM

To determine the impact of molecular analysis on the detection of mucinous cysts and malignancy.

METHODS

An 18-month prospective observational study of consecutive patients with pancreatic cystic lesions and an indication for EUS-FNA following European clinical practice guidelines was conducted. These cysts included those > 15 mm with unclear diagnosis, and a change in follow-up or with concerning features in which results might change clinical management. EUS-FNA with cytological, biochemical and glucose and molecular analyses with next-generation sequencing were performed in 36 pancreatic cysts. The cysts were classified as mucinous and non-mucinous by the combination of morphological, cytological and biochemical analyses when surgery was not performed. Malignancy was defined as cytology positive for malignancy, high-grade dysplasia or invasive carcinoma on surgical specimen, clinical or morphological progression, metastasis or death related to neoplastic complications during the 6-mo follow-up period. Next-generation sequencing results were compared for cyst type and malignancy.

RESULTS

Of the 36 lesions included, 28 (82.4%) were classified as mucinous and 6 (17.6%) as non-mucinous. Furthermore, 5 (13.9%) lesions were classified as malignant. The amount of deoxyribonucleic acid obtained was sufficient for molecular analysis in 25 (69.4%) pancreatic cysts. The amount of intracystic deoxyribonucleic acid was not statistically related to the cyst fluid volume obtained from the lesions. Analysis of KRAS and/or GNAS showed 83.33% [95% confidence interval (CI): 63.34-100] sensitivity, 60% (95%CI: 7.06-100) specificity, 88.24% (95%CI: 69.98-100) positive predictive value and 50% (95%CI: 1.66-98.34) negative predictive value (P = 0.086) for the diagnosis of mucinous cystic lesions. Mutations in KRAS and GNAS were found in 2/5 (40%) of the lesions classified as non-mucinous, thus recategorizing those lesions as mucinous neoplasms, which would have led to a modification of the follow-up plan in 8% of the cysts in which molecular analysis was successfully performed. All 4 (100%) malignant cysts in which molecular analysis could be performed had mutations in KRAS and/or GNAS, although they were not related to malignancy (P > 0.05). None of the other mutations analyzed could detect mucinous or malignant cysts with statistical significance (P > 0.05).

CONCLUSION

Molecular analysis can improve the classification of pancreatic cysts as mucinous or non-mucinous. Mutations were not able to detect malignant lesions.

Practical Applications of Molecular Testing in the Cytologic Diagnosis of Pancreatic Cysts

Mucinous pancreatic cysts are precursor lesions of ductal adenocarcinoma. Discoveries of the molecular alterations detectable in pancreatic cyst fluid (PCF) that help to define a mucinous cyst and its risk for malignancy have led to more routine molecular testing in the preoperative evaluation of these cysts. The differential diagnosis of pancreatic cysts is broad and ranges from non-neoplastic to premalignant to malignant cysts. Not all pancreatic cysts—including mucinous cysts—require surgical intervention, and it is the preoperative evaluation with imaging and PCF analysis that determines patient management. PCF analysis includes biochemical and molecular analysis, both of which are ancillary studies that add significant value to the final cytological diagnosis. While testing PCF for carcinoembryonic antigen (CEA) is a very specific test for a mucinous etiology, many mucinous cysts do not have an elevated CEA. In these cases, detection of a KRAS and/or GNAS mutation is highly specific for a mucinous etiology, with GNAS mutations supporting an intraductal papillary mucinous neoplasm. Late mutations in the progression to malignancy such as those found in TP53, p16/CDKN2A, and/or SMAD4 support a high-risk lesion. This review highlights PCF triage and analysis of pancreatic cysts for optimal cytological diagnosis.

Long-term follow-up of Branch-Duct Intraductal Papillary Mucinous Neoplasms with negative Sendai Criteria: the therapeutic challenge of patients who convert to positive Sendai Criteria

BACKGROUND

The management of Branch-Duct Intraductal Papillary Mucinous Neoplasm (BD-IPMN) is still controversial. Our objective was to assess the long-term follow-up (FU) of patients with "low-risk" BD-IPMN according to the Sendai-International Consensus Guidelines (ICG-I).

METHODS

We retrospectively analyzed a cohort of patients with BD-IPMN and Negative Sendai-Criteria (NSC) from January 2004 to October 2019. A univariate analysis was performed to determine factors associated with conversion to Positive Sendai-Criteria (PSC) and malignancy. Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of the IGC-I were assessed for the development of malignancy.

RESULTS

A total of 219 patients were selected and underwent a median 58-month FU. Thirty-seven (17%) patients developed PSC during FU including 12 (5.5%) with malignant lesions. Conversely, 182 patients (83%) did not develop malignancy. The NPV and PPV of ICG-I for malignancy were 100% and 32.4%, respectively. Among patients who developed PSC, those with cancer were >65years (OR = 3.57;p = 0.015) and had significantly higher serum CA-19-9 levels (OR = 5.27;p = 0.007).

CONCLUSION

The ICG-I is a safe strategy for FU of patients with BD-IPMN. The absence of PSC exclude malignancy. Among patients who develops PSC, the risk of cancer remains low and surgery should be decided according to their surgical risk and life expectancy.

Endoscopic ultrasound with fine needle aspiration is useful in pancreatic cysts smaller than 3 cm

Background

In current guidelines, endoscopic ultrasound with fine-needle aspiration (EUS-FNA) is recommended in pancreatic cystic lesions (PCLs) with worrisome features (size ≥ 3 cm, mural nodule, or Wirsung dilation).

Objective

To evaluate the diagnostic ability and assess the accuracy of EUS-FNA in PCLs smaller than 3 cm.

Methods

Retrospective study of PCLs < 3 cm (2007–2016) undergoing EUS-FNA. Clinical, EUS and pancreatic cystic fluid (PCF) data were prospectively registered. Performance of EUS-FNA with PCF analysis for the detection of malignancy and accuracy in surgical cohort were analyzed.

Results

We evaluated 115 patients with PCLs < 3 cm who underwent EUS-FNA. 19 patients underwent surgery, 7 had malignant, 8 pre-malignant, and the remaining 4 benign lesions. Mass/mural nodule was present in 27% of the cysts, CEA level was higher than 192 ng/mL in 39.4% of patients, and only 35% of cytologic samples were informative. Nevertheless, additional FNA for PCF analysis improved the diagnostic performance of EUS imaging—AUC = 0.80 versus AUC = 60.

Conclusion

EUS-FNA has good accuracy in PCLs < 3 cm. It confirmed malignancy even in lesions without worrisome features (nodule/mass), with two in every five resections showing high-risk/malignant lesions. EUS-FNA was also useful to diagnose benign cysts, possibly allowing surveillance to be stopped in one in every five patients.

Diagnostic performance of current guidelines and postoperative outcome following surgical treatment of cystic pancreatic lesions - a 10-year single center experience

OBJECTIVE

Pancreatic cystic lesions (PCLs) are diagnostically challenging and there are currently several different guidelines. The aim of this study was to compare diagnostic performance of the most widely utilized International Association of Pancreatology (IAP) guidelines and the recent evidence-based European guidelines and to report on postoperative outcomes following surgical treatment of PCLs.

METHODS

This is a retrospective single-center study of patients undergoing surgery due to a PCL between 2010 and 2019. Primary outcome was a comparison of diagnostic performance between IAP and European guidelines, measured in area under the receiver operating characteristic curve (AUC). Other outcomes included diagnostic performance of different risk features, 30-day postoperative mortality and major morbidity, final diagnosis, and overall survival.

RESULTS

We identified 137 patients, three of whom did not undergo curative surgery due to metastatic disease. Overall, there was no difference in the performance of the two guidelines with AUC values ranging from 0.572-0.610 and 0.607-0.621 for IAP and European guidelines respectively. Postoperative 30-day mortality and major morbidity were 0% (95% CI 0.0-2.7%) and 37.3% (95% CI 29.1-46.1%), respectively. More than half of the resected lesions (52.6%) were low-grade dysplastic or non-neoplastic.

CONCLUSIONS

Overall, the IAP and the European guidelines performed equally, although European guidelines had a slightly higher mean specificity. Pancreatic surgery is associated with high major morbidity, and there is a need for new diagnostic tools and strategies in order to decrease the amount of overtreatment in patients with PCL.

Clinical and Economic Outcomes of Patients Undergoing Guideline-Directed Management of Pancreatic Cysts

INTRODUCTION

Numerous guidelines exist for the management of pancreatic cysts. We sought to compare the guideline-directed management strategies for pancreatic cysts by comparing 2 approaches (2017 International Consensus Guidelines and 2015 American Gastroenterological Association Guidelines) that differ significantly in their thresholds for imaging, surveillance, and surgery.

METHODS

We developed a Monte Carlo model to evaluate the outcomes for a cohort of 10,000 patients managed per each guideline. The primary outcome was mortality related to pancreatic cyst management. Secondary outcomes included all-cause mortality, missed cancers, number of surgeries, number of imaging studies, cumulative cost, and quality-adjusted life years.

RESULTS

Deaths because of pancreatic cyst management and quality-adjusted life years were similar in both guidelines at a significantly higher cost of $3.6 million per additional cancer detected in the Consensus Guidelines. Deaths from "unrelated" causes (1,422) vastly outnumbered deaths related to pancreatic cysts (125). Secondary outcomes included more missed cancers in the American Gastroenterological Association guideline (71 vs 49), more surgeries and imaging studies in the Consensus guideline (711 vs 163; 116,997 vs 68,912), and higher cost in the Consensus guideline ($168.3 million vs $89.4 million). As the rate of malignant transformation increases, a more-intensive guideline resulted in fewer deaths related to pancreatic cyst management.

DISCUSSION

Our study demonstrates trade-offs between more- and less-intensive management strategies for pancreatic cysts. Although deaths related to pancreatic cyst management were similar in each strategy, fewer missed cancers in the more-intensive surveillance strategy is offset by a greater number of surgical deaths and higher cost. In conclusion, our study identifies that if the rate malignant transformation of pancreatic cysts is low (0.12% annually), a less-intensive guideline will result in similar deaths to a more-intensive guideline at a much lower cost.

Intraductal Pancreatic Mucinous Neoplasms: A Tumor-Biology Based Approach for Risk Stratification

Pancreatic ductal adenocarcinoma is one of the most lethal human cancers. Its precursor lesions include pancreatic intra-epithelial neoplasia, mucinous cystic neoplasm, and intraductal papillary mucinous neoplasm (IPMN). IPMNs usually present as an incidental finding at imaging in 2.6% of the population and, according to the degree of dysplasia, they are classified as low- or high-grade lesions. Since the risk of malignant transformation is not accurately predictable, the management of these lesions is based on morphological and clinical parameters, such as presence of mural nodule, main pancreatic duct dilation, presence of symptoms, or high-grade dysplasia. Although the main genetic alterations associated to IPMNs have been elucidated, they are still not helpful for disease risk stratification. The growing body of genomic and epigenomic studies along with the more recent development of organotypic cultures provide the opportunity to improve our understanding of the malignant transformation process, which will likely deliver biomarkers to help discriminate between low- and high-risk lesions. Recent insights on the topic are herein summarized.

Diagnostic approaches for pancreatic cystic lesions

BACKGROUND

Cystic lesions of the pancreas (PCLs) may be inflammatory or proliferative and making an accurate and timely pre-operative diagnosis remains a significant clinical challenge. This is principally due to the heterogeneity of the pathological processes involved. PCLs constitute an entity with diverse histology and although infrequent, the possible potential for malignant transformation of these lesions and the opportunity for curative surgery mandates that our diagnostic approaches are up to date and evidence based. In addition, improved diagnostic accuracy is crucial to prevent unnecessary surgical procedures with the inevitable associated morbidity.

METHODS

This narrative review examines the current diagnostic benchmarks and identifies novel diagnostic techniques that warrant further consideration, a number of which are beginning to be included in routine clinical practice when these PCLs are being investigated. A computerized search was made of MEDLINE, EMBASE and PubMed using the search words 'diagnostic approaches to pancreatic cystic lesions'. All relevant articles in English language or with an English abstract were retrieved and additionally cross referenced.

CONCLUSION

The increasing accuracy of available imaging techniques together with the wider availability of endoluminal ultrasound and the development of additional novel methods to assess PCLs presents an opportunity to significantly improve the pre-operative diagnosis rate. This is essential to classify the type of PCL and hence guide the management particularly with lesions where there is a likelihood of progression to more serious pathology. We have highlighted the need for a comprehensive and standardized algorithm for the diagnosis and management of PCLs.

Endosonographic diagnosis of advanced neoplasia in intraductal papillary mucinous neoplasms

Pancreatic cancer has a high mortality rate with minimal proven interventions. Intraductal Papillary Mucinous Neoplasms (IPMNs) are known precursor lesions for pancreatic cancer. Identification of pancreatic cysts has improved from advances in abdominal imaging. Despite multiple revisions of the international consensus recommendations and various guidelines by other major societies, successful risk stratification of the malignant potential of mucinous pancreatic cysts remains challenging. Specifically, detection and accurate classification of advanced neoplasia (high-grade dysplasia and/or adenocarcinoma) in IPMNs is suboptimal with current diagnostic strategies. Development of interventional techniques utilizing endoscopic ultrasound include - through-the-needle microforceps biopsy, next-generation or whole genome molecular analysis of cyst fluid, and needle-based confocal laser endomicroscopy. These techniques suffer from a series of limitations in technical success, diagnostic yield, and clinical feasibility, but a combination approach may offer a solution that optimizes their cyst evaluation and risk stratification. Assessment and comparison of these techniques is restricted by lack of adequate surgical specimens for testing of diagnostic accuracy, resulting in a possible sample bias. Additional large-scale multicenter studies are needed to accumulate evidence for the utility and feasibility of their translation into clinical practice. Great strides have been made in pancreatic cyst evaluation, but further research is required to improve diagnostic accuracy and clinical management of IPMNs.

Molecular Diagnostics and Testing for Pancreatic Cysts

PURPOSE OF REVIEW

In current clinical practice, the diagnosis and management of pancreatic cystic lesions (PCLs) are based on guidelines that combine clinical and imaging findings. These guidelines usefully identify a large category of low-risk PCLs that do not require treatment. However, they have limited accuracy for diagnosis of advanced neoplasia in worrisome and high-risk PCLs. Novel molecular markers that can accurately detect advanced neoplasia in PCLs can transform the care of patients with PCLs. We reviewed the recent medical literature on molecular diagnostics of PCLs and summarized molecular biomarkers assayed in cyst fluid, pancreatic juice, and blood.

RECENT FINDINGS

Several studies have been recently published describing promising early results in genetic, epigenetic, and protein biomarkers from cyst fluid to help in both histologic diagnosis and detection of advanced neoplasia. The majority of studies have been completed using opportunistically collected archival cyst fluid and few report validation in independent sample sets. Results of ongoing multicenter prospective validation studies are awaited and will help define the best combination of cyst fluid molecular markers. In multifocal PCLs communicating with the pancreatic ductal system, a pancreatic juice biomarker is likely to be less invasive and more informative. Novel biomarkers in pancreatic juice and blood are in early phases of study.

SUMMARY

The field of molecular diagnostic biomarkers for PCLs is rapidly evolving with several promising candidate markers being prospectively evaluated. In the near future, these novel molecular markers, combined with advances in imaging technology, will transform clinical decision-making in the management of PCLs and improve patient outcomes.

Stratifying Intraductal Papillary Mucinous Neoplasms by Cyst Fluid Analysis: Present and Future

A significant proportion of patients with intraductal papillary mucinous neoplasms (IPMNs) undergo surgical resection in order to prevent or treat pancreatic cancer at the risk of significant perioperative morbidity. Efforts have been made to stratify the potential risk of malignancy based on the clinical and radiographic features of IPMN to delineate which cysts warrant resection versus observation. An analysis of the cyst fluid obtained by preoperative endoscopic examination appears to be correlative of cyst type and risk, whereas serum markers and radiographic findings have not yet reached a level of sensitivity or specificity that proves they are clinically meaningful. In this review, we investigate the current cyst fluid analysis studies and present those that have shown promise in effectively stratifying high-risk versus low-risk lesions. While new cyst fluid markers continue to be identified, additional efforts in testing panels and marker composites in conjunction with clinical algorithms have also shown promise in distinguishing dysplasia and the risk of malignancy. These should be tested prospectively in order to determine their role in guiding the surveillance of low-risk lesions and to evaluate the new markers detected by proteomics and genetic sequencing.

Pancreatic mucinous cystic neoplasms: a clinicopathological study of 11 cases and detailed review of literature

Background

Mucinous cystic neoplasms (MCNs) of pancreas are relatively rare, occur almost exclusively in middle-aged females, and are overwhelmingly located in the body and tail of the pancreas, histologically show an ovarian type stroma. MCNs are premalignant, low aggressive tumors. Here we describe the clinicopathologic and radiologic features and follow up of cases diagnosed in our practice. We also present a detailed review of recent literature.

Materials and methods

Based on strict criteria, 11 cases diagnosed between 2002 and 2016 were included in the study.

Results

All cases were reviewed histologically. Mean and median age was 46.7 and 46 years respectively. All patients were females and 9 out of 11 cases were located in the body and/or tail of the pancreas. Mean tumor size was 8 cm. Grossly, cysts were uni or multilocular and ranged from a few millimeters to several centimeters in diameter. Microscopically, all cases showed characteristic tall columnar, mucin producing epithelium and ovarian type stroma. Atypia was mild in 8 cases and severe in 3 cases. The latter 3 cases were classified as non-invasive MCNs with high grade dysplasia (2 cases) and MCN with an associated invasive carcinoma (1 case). On immunohistochemistry, all cases showed epithelial positivity for cytokeratin AE1/AE3 and stromal positivity for vimentin and smooth muscle actin. Follow up was available in 7 cases. All patients were alive and well with no recurrence.

Conclusions

Our cases show features similar to those described in other published studies although cases in our series tended to be larger in number. Since these tumors are relatively rare, premalignant and have strict diagnostic criteria, they must always be considered in the differential diagnosis of pancreatic mucinous cystic lesions. Larger studies incorporating greater number of patients and more detailed follow up will help in increasing our understanding of MCNs.

Pancreatic Cysts in the Elderly

PURPOSE OF REVIEW

Incidental pancreatic cysts are common, and management strategies continue to evolve. This review summarizes diagnostic and management recommendations in older patients with these lesions based on guidelines and best clinical evidence.

RECENT FINDINGS

Diagnosis of cyst type has been enhanced with improved imaging and cyst fluid analysis and visualization. Recent outcome studies indicate that certain cyst types should be followed independent of patient age as long as certain criteria which are reviewed are met. Differentiation of pancreatic cyst type is important as this dictates the need for long-term follow-up. Because most cyst-related neoplasia occurs in older patients, surveillance should continue within certain guidelines.

Pancreatic Cancer Surveillance: Who, When, and How

PURPOSE OF REVIEW

Individuals who have an increased risk for pancreatic cancer (PC) due to personal or family history may benefit from surveillance of the pancreas to increase the likelihood of early detection. This review explores current indications for PC surveillance, as well as options for surveillance modality and timing, and data regarding surveillance outcomes.

RECENT FINDINGS

Recently published data suggests that individuals undergoing surveillance who develop PC are more likely to be diagnosed with resectable disease, which improves survival. Several professional organizations have published guidelines for surveillance to help define who should have surveillance, when surveillance should be performed, and how it can be accomplished. PC surveillance should be considered for individuals with a pathogenic variant in a PC-related gene who have an affected first- or second-degree relative and for individuals in a familial pancreatic cancer family who have an affected first-degree relative. Surveillance should begin at age 50, or 10 years before the earliest age of PC diagnosis in the family. Endoscopic ultrasound (EUS) or MRI/MRCP are both reasonable surveillance options, but EUS may be better at detecting small solid changes in the pancreas. Ideally, surveillance should be performed at expert centers in conjunction with research protocols.

Diagnosis and management of pancreatic cystic neoplasms: current evidence and guidelines

Pancreatic cystic neoplasms (PCN) are a heterogeneous group of pancreatic cysts that include intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, serous cystic neoplasms and other rare cystic lesions, all with different biological behaviours and variable risk of progression to malignancy. As more pancreatic cysts are incidentally discovered on routine cross-sectional imaging, optimal surveillance for patients with PCN is becoming an increasingly common clinical problem, highlighting the need to balance cancer prevention with the risk of (surgical) overtreatment. This Review summarizes the latest developments in the diagnosis and management of PCN, including the quality of available evidence. Also discussed are the most important differences between the PCN guidelines from the American Gastroenterological Association, the International Association of Pancreatology and the European Study Group on Cystic Tumours of the Pancreas, including diagnostic and follow-up strategies and indications for surgery. Finally, new developments in the management of patients with PCN are addressed.

Accuracy of Fukuoka and American Gastroenterological Association Guidelines for Predicting Advanced Neoplasia in Pancreatic Cyst Neoplasm: A Meta-Analysis

BACKGROUND

A differential diagnosis of advanced pancreatic cystic neoplasms (PCNs) is critical to determine optimal treatment. The Fukuoka and American Gastroenterological Association (AGA) guidelines are the most widely accepted criteria for the management of PCNs.

OBJECTIVE

This study aimed to evaluate the diagnostic value of these guidelines in predicting advanced neoplasia (AN).

METHODS

A comprehensive electronic search of the PubMed, EMBASE, Web of Science, Cochrane Library, and Scopus databases was conducted to identify all relevant studies evaluating the Fukuoka and AGA guidelines in surgically resected and histologically confirmed PCNs. Pooled sensitivity, specificity, and diagnostic odds ratios (DORs) were calculated as compound measures of diagnostic accuracy using the random-effects model. Summary of receiver operating characteristic (SROC) curves and the area under the curve (AUC) were also performed.

RESULTS

A total of 21 studies with 3723 patients were included in this meta-analysis. Of these studies, 15, 4, and 2 evaluated the Fukuoka guidelines, the AGA guidelines, and both guidelines, respectively. For AN prediction, the Fukuoka guidelines had a pooled sensitivity of 0.67 (95% confidence interval [CI] 0.64-0.70), pooled specificity of 0.64 (95% CI 0.62-0.66), and pooled DOR of 6.28 (95% CI 4.38-9.01), with an AUC of the SROC of 0.78. AGA guidelines showed a pooled sensitivity of 0.59 (95% CI 0.52-0.65), pooled specificity of 0.77 (95% CI 0.74-0.80), and pooled DOR of 5.84 (95% CI 2.60-13.15), with an AUC of 0.79 (95% CI 0.70-0.88).

CONCLUSION

When used alone, the Fukuoka and AGA guidelines showed similar but unsatisfactory diagnostic accuracy in the risk stratification of malignant potential of PCN. Thus, we recommend that they be applied only as a broad framework in clinical practice.

Cytologic Analysis of Pancreatic Juice Increases Specificity of Detection of Malignant IPMN-A Systematic Review

BACKGROUND & AIMS

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas can progress to cancer. Biomarkers have been identified that were reported to increase the accuracy of identification of malignant lesions; we performed a systematic review of the accuracy of these markers.

METHODS

We performed a systematic review of published studies on biomarkers of malignant IPMNs by searching MEDLINE and Web of Science databases from January 2005 through December 2017. Our methods were developed based on the Meta-analysis Of Observational Studies in Epidemiology guidelines. Pooled sensitivity, specificity, receiver operating characteristic curves, and their respective areas under the curve (AUC) were calculated from groups of markers (cell-, protein-, or DNA-based) measured in samples collected before and after surgery. A hypothetical test model was developed to determine how to meaningfully amend the revised Fukuoka guidelines, focusing on increasing test specificity for patients with IPMNs that have worrisome features.

RESULTS

We collected data from 193 published studies, comprising 12,297 patients, that analyzed 7 preoperative and 21 postoperative markers of IPMNs. The 3 biomarkers that identified malignant IPMNs with the largest AUC values were pancreatic juice cytology (AUC, 0.84; sensitivity, 0.54; specificity, 0.91), serum protein carbohydrate antigen 19-9 (AUC, 0.81; sensitivity, 0.45; specificity, 0.90), and cyst fluid cytology (AUC, 0.82; sensitivity, 0.57; specificity, 0.84). A combination of cytologic and immunohistochemical analysis of MUC1 and MUC2 in pancreatic juice samples identified malignant IPMNs with the largest AUC and sensitivity values (AUC, 0.85; sensitivity, 0.85; specificity, 0.65). In a test model, inclusion of cytologic analysis of pancreatic juice in the guideline algorithm significantly increased the specificity of detection of malignant IPMNs.

CONCLUSIONS

In a systematic review, we found cytologic analysis of pancreatic juice to have the greatest effect in increasing the specificity of detection of malignant IPMNs. We propose addition of this test to the Fukuoka guidelines for assessment of patients with IPMNs with worrisome features.

Novel Methylated DNA Markers Discriminate Advanced Neoplasia in Pancreatic Cysts: Marker Discovery, Tissue Validation, and Cyst Fluid Testing

OBJECTIVES

Pancreatic cystic lesions (PCLs) may be precancerous. Those likely to harbor high-grade dysplasia (HGD) or pancreatic cancer (PC) are targets for surgical resection. Current algorithms to predict advanced neoplasia (HGD/PC) in PCLs lack diagnostic accuracy. In pancreatic tissue and cyst fluid (CF) from PCLs, we sought to identify and validate novel methylated DNA markers (MDMs) that discriminate HGD/PC from low-grade dysplasia (LGD) or no dysplasia (ND).

METHODS

From an unbiased whole-methylome discovery approach using predefined selection criteria followed by multistep validation on case (HGD or PC) and control (ND or LGD) tissues, we identified discriminant MDMs. Top candidate MDMs were then assayed by quantitative methylation-specific polymerase chain reaction on archival CF from surgically resected PCLs.

RESULTS

Of 25 discriminant MDMs identified in tissue, 13 were selected for validation in 134 CF samples (21 cases [8 HGD, 13 PC], 113 controls [45 ND, 68 LGD]). A tree-based algorithm using 2 CF-MDMs (TBX15, BMP3) achieved sensitivity and specificity above 90%. Discrimination was significantly better by this CF-MDM panel than by mutant KRAS or carcinoembryonic antigen, with areas under the receiver operating characteristic curve of 0.93 (95% confidence interval: 0.86-0.99), 0.71 (0.57-0.85), and 0.72 (0.60-0.84), respectively. Cutoffs for the MDM panel applied to an independent CF validation set (31 cases, 56 controls) yielded similarly high discrimination, areas under the receiver operating characteristic curve = 0.86 (95% confidence interval: 0.77-0.94, P = 0.2).

DISCUSSION

Novel MDMs discovered and validated in tissue accurately identify PCLs harboring HGD/PC. A panel of 2 MDMs assayed in CF yielded results with potential to enhance current risk prediction algorithms. Prospective studies are indicated to optimize and further evaluate CF-MDMs for clinical use.

Clinical validation of the 2017 international consensus guidelines on intraductal papillary mucinous neoplasm of the pancreas

Purpose

The 2017 international consensus guidelines (ICG) for intraductal papillary mucinous neoplasm (IPMN) of the pancreas were recently released. Important changes included the addition of worrisome features such as elevated serum CA 19-9 and rapid cyst growth (>5 mm over 2 years). We aimed to clinically validate the 2017 ICG and compare the diagnostic performance between the 2017 and 2012 ICG.

Methods

This was a retrospective cohort study. During January 2000–January 2017, patients who underwent complete surgical resection and had pathologic confirmation of branch-duct or mixed-type IPMN were included. To evaluate diagnostic performance, the areas under the receiver operating curves (AUCs) were evaluated.

Results

A total of 448 patients were included. The presence of mural nodule (hazard ratio [HR], 9.12; 95% confidence interval [CI], 4.60–18.09; P = 0.001), main pancreatic duct dilatation (>5 mm) (HR, 5.32; 95% CI, 2.67–10.60; P = 0.001), thickened cystic wall (HR, 3.40; 95% CI, 1.51–7.63; P = 0.003), and elevated CA 19-9 level (>37 unit/mL) (HR, 5.25; 95% CI, 2.05–13.42; P = 0.001) were significantly associated with malignant IPMN. Malignant lesions showed a cyst growth rate >5 mm over 2 years more frequently than benign lesions (60.9% vs. 29.7%, P = 0.012). The AUC was higher for the 2017 ICG than the 2012 ICG (0.784 vs. 0.746).

Conclusion

The new 2017 ICG for IPMN is clinically valid, with a superior diagnostic performance to the 2012 ICG. The inclusion of elevated serum CA 19-9 level and cyst growth rate to the 2017 ICG is appropriate.

Genetic testing vs microforceps biopsy in pancreatic cysts: Systematic review and meta-analysis

BACKGROUND

Carcinoembryonic antigen (CEA) and cytology in pancreatic cystic fluid are suboptimal for evaluation of pancreatic cystic neoplasms. Genetic testing and microforceps biopsy are promising tools for pre-operative diagnostic improvement but comparative performance of both methods is unknown.

AIM

To compare the accuracy of genetic testing and microforceps biopsy in pancreatic cysts referred for surgery.

METHODS

We performed a literature search in Medline, Scopus, and Web of Science for studies evaluating genetic testing of cystic fluid and microforceps biopsy of pancreatic cysts, with endoscopic ultrasound with fine-needle aspiration (EUS-FNA) prior to surgery and surgical pathology as reference standard for diagnosis. We evaluated the diagnostic accuracy for: 1- benign cysts; 2- mucinous low-risk cysts; 3- high-risk cysts, and the diagnostic yield and rate of correctly identified cysts with microforceps biopsy and molecular analysis. We also assessed publication bias, heterogeneity, and study quality.

RESULTS

Eight studies, including 1206 patients, of which 203 (17%) referred for surgery who met the inclusion criteria were analyzed in the systematic review, and seven studies were included in the meta-analysis. Genetic testing and microforceps biopsies were identical for diagnosis of benign cysts. Molecular analysis was superior for diagnosis of both low and high-risk mucinous cysts, with sensitivities of 0.89 (95%CI: 0.79-0.95) and 0.57 (95%CI: 0.42-0.71), specificities of 0.88 (95%CI: 0.75-0.95) and 0.88 (95%CI: 0.80-0.93) and AUC of 0.9555 and 0.92, respectively. The diagnostic yield was higher in microforceps biopsies than in genetic analysis (0.73 vs 0.54, respectively) but the rates of correctly identified cysts were identical (0.73 with 95%CI: 0.62-0.82 vs 0.71 with 95%CI: 0.49-0.86, respectively).

CONCLUSION

Genetic testing and microforceps biopsies are useful second tests, with identical results in benign pancreatic cysts. Genetic analysis performs better for low- and high-risk cysts but has lower diagnostic yield.

KRAS in Cyst Fluid Obtained by Endoscopic Ultrasound-Fine-Needle Aspiration in Pancreatic Cystic Lesions: A Systematic Review and Meta-analysis

To evaluate the diagnostic accuracy of KRAS mutation in pancreatic cystic fluid and compare it with carcinoembryonic antigen and cytology, we identified studies with cyst fluid obtained by endoscopic ultrasound prior to surgery. We classified cysts as malignant, premalignant, and benign. A random-effects model was used for quantitative meta-analysis. Pooled sensitivities, specificities, and summary receiver operating characteristic curve analysis were conducted. We analyzed 16 studies, with 3429 patients, including 731 referred for surgery. Carcinoembryonic antigen was better for clinically significant cysts (premalignant and malignant) with sensitivity = 0.58 (95% confidence interval [CI], 0.53-0.65), specificity = 0.9 (95% CI, 0.76-0.97), and area under the curve (AUC) = 0.69. Cytology performed better in malignant cysts, with sensitivity = 0.37 (95% CI, 0.27-0.48), specificity = 0.96 (95% CI, 0.93-0.98), and AUC = 0.78. Isolated, KRAS mutation failed the diagnosis of malignant and significant cysts, with sensitivities = 0.43 (95% CI, 0.34-0.43) and 0.46 (95% CI, 0.42-0.51), specificities = 0.62 (95% CI, 0.56-0.68) and 0.97 (95% CI, 0.92-0.99), and AUCs = 0.56 and 0.53, respectively. Carcinoembryonic antigen and cytology are more accurate than KRAS. Additional studies are lacking to recommend KRAS as a single diagnostic test.

Somatic molecular analysis augments cytologic evaluation of pancreatic cyst fluids as a diagnostic tool

Objective: Better tools are needed for early diagnosis and classification of pancreatic cystic lesions (PCL) to trigger intervention before neoplastic precursor lesions progress to adenocarcinoma. We evaluated the capacity of molecular analysis to improve the accuracy of cytologic diagnosis for PCL with an emphasis on non-diagnostic/negative specimens. Design: In a span of 7 years, at a tertiary care hospital, 318 PCL endoscopic ultrasound-guided fine needle aspirations (EUS-FNA) were evaluated by cytologic examination and molecular analysis. Mucinous PCL were identified based on a clinical algorithm and 46 surgical resections were used to verify this approach. The mutation allele frequency (MAF) of commonly altered genes (BRAF, CDKN2A, CTNNB1, GNAS, RAS, PIK3CA, PTEN, SMAD4, TP53 and VHL) was evaluated for their ability to identify and grade mucinous PCL. Results: Cytology showed a diagnostic sensitivity of 43.5% for mucinous PCL due in part to the impact of non-diagnostic (28.8%) and negative (50.5%) specimens. Incorporating an algorithmic approach or molecular analysis markedly increased the accuracy of cytologic evaluation. Detection of mucinous PCL by molecular analysis was 93.3% based on the detection of KRAS and/or GNAS gene mutations (p = 0.0001). Additional genes provided a marginal improvement in sensitivity but were associated with cyst type (e.g. VHL) and grade (e.g. SMAD4). In the surgical cohort, molecular analysis and the proposed algorithm showed comparable sensitivity (88.9% vs. 100%). Conclusions: Incorporating somatic molecular analysis in the cytologic evaluation of EUS-FNA increases diagnostic accuracy for detection, classification and grading of PCL. This approach has the potential to improve patient management.

Early Detection of Pancreatic Cancer: Opportunities and Challenges

Most patients with pancreatic ductal adenocarcinoma (PDAC) present with symptomatic, surgically unresectable disease. Although the goal of early detection of PDAC is laudable and likely to result in significant improvement in overall survival, the relatively low prevalence of PDAC renders general population screening infeasible. The challenges of early detection include identification of at-risk individuals in the general population who would benefit from longitudinal surveillance programs and appropriate biomarker and imaging-based modalities used for PDAC surveillance in such cohorts. In recent years, various subgroups at higher-than-average risk for PDAC have been identified, including those with familial risk due to germline mutations, a history of pancreatitis, patients with mucinous pancreatic cysts, and elderly patients with new-onset diabetes. The last 2 categories are discussed at length in terms of the opportunities and challenges they present for PDAC early detection. We also discuss current and emerging imaging modalities that are critical to identifying early, potentially curable PDAC in high-risk cohorts on surveillance.

EUS-Guided Pancreatic Cyst Ablation: a Clinical and Technical Review

PURPOSE OF REVIEW

Pancreatic cystic lesions represent a growing public health dilemma, particularly as our population ages and cross-sectional imaging becomes more sensitive. Mucinous cysts carry a clinically significant risk of developing pancreatic cancer, which carries an extremely poor prognosis. Determining which cysts will develop cancer may be challenging, and surgical resection of the pancreas carries significant morbidity. The goal of this paper is to review the rationale for cyst ablation and discuss prior and current research on cyst ablation techniques and efficacy. Indications, contraindications, and factors related to optimal patient selection are outlined.

RECENT FINDINGS

Endoscopic ultrasound-guided chemoablation of pancreatic cysts has been performed in neoplastic cysts, with varying levels of efficacy. Safety concerns arose due to the risk of pancreatitis in alcohol-based treatments; however, the most recent data using a non-alcohol chemoablation cocktail suggests that ablation is effective without the need for alcohol, resulting in a significantly more favorable adverse event profile. Endoscopic ultrasound-guided chemoablation of neoplastic pancreatic cysts is a promising, minimally invasive approach for treatment of cysts, with recent significant advances in safety and efficacy, suggesting that it should play a role in the treatment algorithm.

Age and cystic size are associated with clinical impact of endoscopic ultrasonography-guided fine-needle aspiration on the management of pancreatic cystic neoplasms

Objectives: The clinical impact of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) in managing pancreatic cystic neoplasms (PCNs) remains controversial. The aim of this study was to identify which patients with PCNs would benefit from EUS-FNA. Methods: A retrospective study was performed on patients with PCNs who underwent EUS-FNA between January 2009 and June 2018. A discordant or a consistent diagnosis after EUS-FNA was analyzed and was correlated with the clinical demographic data and cystic features. Predictors of the change in the diagnosis after EUS-FNA were analyzed. Results: One hundred eighty-eight cases of PCNs were analyzed. EUS-FNA changed the diagnosis in 45.7% of all patients with PCNs and 54.5% patients with presumed branch ductal type intraductal papillary mucinous neoplasm (BD-IPMN) and impacted the recommendation in 35.6% of patients with PCNs and 50.5% patients with BD-IPMN. Patients with a discordant diagnosis after EUS-FNA were younger in age (54.8 ± 12.6 vs. 61.2 ± 14.2; p=.037) and had a cyst size larger than 3 cm than patients with a consistent diagnosis after EUS-FNA. The only worrisome feature (WF) that differed between patients with a discordant and a consistent diagnosis after EUS-FNA was the main pancreatic duct (MPD) between 5 and 9 mm (p=.013). In multivariate analysis, a cyst size >3 cm and age were independent predictors of diagnostic changes after EUS-FNA (OR: 5.33, 95% CI: 1.79-15.88, p = .003; OR: 0.96, 95% CI: 0.93-0.99, p  =  .031). Conclusions: EUS-FNA made a significant change in the management of nearly half of the patients with PCNs, especially in younger patients and in patients with a cyst size larger than 3 cm.

Cyst Fluid Biosignature to Predict Intraductal Papillary Mucinous Neoplasms of the Pancreas with High Malignant Potential

BACKGROUND

Current standard-of-care technologies, such as imaging and cyst fluid analysis, are unable to consistently distinguish intraductal papillary mucinous neoplasms (IPMNs) of the pancreas at high risk of pancreatic cancer from low-risk IPMNs. The objective was to create a single-platform assay to identify IPMNs that are at high risk for malignant progression.

STUDY DESIGN

Building on the Verona International Consensus Conference branch duct IPMN biomarker review, additional protein, cytokine, mucin, DNA, and microRNA cyst fluid targets were identified for creation of a quantitative polymerase chain reaction-based assay. This included messenger RNA markers: ERBB2, GNAS, interleukin 1β, KRAS, MUCs1, 2, 4, 5AC, 7, prostaglandin E2R, PTGER2, prostaglandin E synthase 2, prostaglandin E synthase 1, TP63; microRNA targets: miRs 101, 106b, 10a, 142, 155, 17, 18a, 21, 217, 24, 30a, 342, 532, 92a, and 99b; and GNAS and KRAS mutational analysis. A multi-institutional international collaborative contributed IPMN cyst fluid samples to validate this platform. Cyst fluid gene expression levels were normalized, z-transformed, and used in classification and regression analysis by a support vector machine training algorithm.

RESULTS

From cyst fluids of 59 IPMN patients, principal component analysis confirmed no institutional bias/clustering. Lasso (least absolute shrinkage and selection operator)-penalized logistic regression with binary classification and 5-fold cross-validation used area under the curve as the evaluation criterion to create the optimal signature to discriminate IPMNs as low risk (low/moderate dysplasia) or high risk (high-grade dysplasia/invasive cancer). The most predictive signature was achieved with interleukin 1β, MUC4, and prostaglandin E synthase 2 to accurately discriminate high-risk cysts from low-risk cysts with an area under the curve of up to 0.86 (p = 0.002).

CONCLUSIONS

We have identified a single-platform polymerase chain reaction-based assay of cyst fluid to accurately predict IPMNs with high malignant potential for additional studies.

Pancreatic Cysts: Sinister Findings or Incidentalomas?

Pancreatic cysts are common and are incidentally detected in up to 13.5% of individuals. Intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm (MCN) are precursors to pancreatic adenocarcinoma. Most will never develop into pancreatic cancer. Several types of pancreatic cysts have no malignant potential. Solid tumors can present as a pancreatic cysts. Guidelines recommend surveillance. Management includes differentiating IPMNs and MCNs from other types, identifying those at highest risk of harboring pancreatic cancer or high-grade dysplasia, and referral to a multidisciplinary group for evaluation and consideration of surgical resection.

[Intraductal papillary mucinous neoplasm of pancreas]

Intraductal papillary mucinous neoplasm (IPMN) is the most common cystic pancreatic tumor. There are 3 ductal types of this tumor depending on localization. Several histological subtypes determine clinical course and prognosis. The problems of diagnosis, surgical treatment and follow-up are reviewed in several guidelines. Literature review devoted to pancreatic IPMN is presented in the article, the latest guidelines are compared.