Performance of Intracystic Glucose Measurement for the Characterization of Pancreatic Cystic Lesions

BACKGROUND AND AIMS

Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) is essential for the classification of pancreatic cystic lesions (PCLs). Recently, intracystic glucose has been suggested as an alternative to carcinoembryonic antigen (CEA) level as a predictor of mucinous cystic lesions (M-PCLs). This study aims to evaluate the diagnostic performance of intra-cystic glucose in distinguishing between M-PCLs and non M-PCLs (NM-PCLs) and to analyze the possibility of on-site glucose measurement with a standard glucometer.

METHODS

Patients with PCLs submitted to EUS-FNA with simultaneous intracystic glucose measurement between 2017 and 2022 were included. The diagnostic performance of glucose versus CEA for the differentiation between M-PCLs and NM-PCLs was compared to a final diagnosis based on the analysis of surgical specimen, intracystic biopsy or, if this data was unavailable, multidisciplinary evaluation. A cut-off of <50 mg/dL was used for the diagnosis of MCLs. Additionally, the agreement between on-site glucose determination with a standard glucometer and laboratory glucose measurement was assessed.

RESULTS

Mucinous lesions accounted for 56% of all PCLs. The median values of glucose and CEA for M-PCLs were 18 mg/dL and 286 ng/mL, respectively. Intracystic glucose had a sensitivity and specificity of 93.2% and 76.5%, respectively, for the diagnosis of MCLs (versus 55.6% and 87.5%, respectively, for CEA). The area under the curve was 0.870 for on-site glucose (versus 0.806 for CEA). An excellent correlation was observed between on-site and laboratory glucose measurement (ρ=0.919).

CONCLUSIONS

The measurement of intracystic glucose showed superior performance compared with CEA in distinguishing between M-PCLs and NM-PCLs, with excellent correlation between on-site and conventional lab glucose measurement. Thus, on-site intracystic glucose appears to be an excellent biomarker for the characterization of PCLs due to its low cost, high availability, and the need for a minimal cyst fluid volume for its determination.

Bronchial-biliary fistula secondary to cholangiocarcinoma: long-term efficacy of biliary self-expandable metal stent

A 77-year-old female with previous medical history of non-cirrhotic chronic hepatitis B and hepatocellular carcinoma treated with sequential partial hepatectomy followed by transarterial chemoembolization complained of pruritus and jaundice. Magnetic resonance cholangiopancreatography revealed a peri-hilar ill-defined stenosing lesion suggestive of malignancy. Endoscopic retrograde cholangiopancreatography with cholangioscopy confirmed a circumferential peri-hilar stenosis with fragile mucosa and tortuous dilated vessels and biopsies of this area were consistent cholangiocarcinoma. After 3 months, she presented with new-onset dyspnea and bilioptysis and abdominal computed tomography revealed a bronchial-biliary fistula. ERCP was performed to place a self-expandable metal stent in the biliary tract, which resulted in rapid clinical improvement. The patient has been followed for 2 years and remains globally stable with two episodes of worsening of bilioptysis secondary to stent obstruction by lithiasis that were easily resolved with Fogarty balloon-assisted extraction, with rapid improvement. This case demonstrates the long-term efficacy of endoscopic biliary drainage with self-expandable metallic stent for bronchial-biliary fistula in the setting of cholangiocarcinoma. .

Deep Learning for Automatic Differentiation of Mucinous versus Non-Mucinous Pancreatic Cystic Lesions: A Pilot Study

Endoscopic ultrasound (EUS) morphology can aid in the discrimination between mucinous and non-mucinous pancreatic cystic lesions (PCLs) but has several limitations that can be overcome by artificial intelligence. We developed a convolutional neural network (CNN) algorithm for the automatic diagnosis of mucinous PCLs. Images retrieved from videos of EUS examinations for PCL characterization were used for the development, training, and validation of a CNN for mucinous cyst diagnosis. The performance of the CNN was measured calculating the area under the receiving operator characteristic curve (AUC), sensitivity, specificity, and positive and negative predictive values. A total of 5505 images from 28 pancreatic cysts were used (3725 from mucinous lesions and 1780 from non-mucinous cysts). The model had an overall accuracy of 98.5%, sensitivity of 98.3%, specificity of 98.9% and AUC of 1. The image processing speed of the CNN was 7.2 ms per frame. We developed a deep learning algorithm that differentiated mucinous and non-mucinous cysts with high accuracy. The present CNN may constitute an important tool to help risk stratify PCLs.

Exosomal glypican-1 is elevated in pancreatic cancer precursors and can signal genetic predisposition in the absence of endoscopic ultrasound abnormalities

BACKGROUND

Individuals within specific risk groups for pancreatic ductal adenocarcinoma (PDAC) [mucinous cystic lesions (MCLs), hereditary risk (HR), and new-late onset diabetes mellitus (NLOD)] represent an opportunity for early cancer detection. Endoscopic ultrasound (EUS) is a premium image modality for PDAC screening and precursor lesion characterization. While no specific biomarker is currently clinically available for this purpose, glypican-1 (GPC1) is overexpressed in the circulating exosomes (crExos) of patients with PDAC compared with healthy subjects or those harboring benign pancreatic diseases.

AIM

To evaluate the capacity of GPC1⁺ crExos to identify individuals at higher risk within these specific groups, all characterized by EUS.

METHODS

This cross-sectional study with a prospective unicentric cohort included 88 subjects: 40 patients with MCL, 20 individuals with HR, and 20 patients with NLOD. A control group (CG) was submitted to EUS for other reasons than pancreatic pathology, with normal pancreas and absence of hereditary risk factors (n = 8). The inclusion period was between October 2016 and January 2019, and the study was approved by the Ethics Committee of Centro Hospitalar Universitário de São João, Porto, Portugal. All patients provided written informed consent. EUS and blood tests for quantification of GPC1⁺ crExos by flow cytometry and carbohydrate antigen 19-9 (CA 19-9) levels by ELISA were performed in all subjects. EUS-guided tissue acquisition was done whenever necessary. For statistical analysis, SPSS^® 27.0 (IBM Corp., Armonk, NY, United States) version was used. All graphs were created using GraphPad Prism 7.00 (GraphPad Software, San Diego, CA, United States).

RESULTS

Half of MCLs harbored worrisome features (WF) or high-risk stigmata (HRS). Pancreatic abnormalities were detected by EUS in 10.0% and 35.0% in HR and NLOD individuals, respectively, all considered non-malignant and “harmless.” Median levels of GPC1⁺ crExos were statistically different: MCL [99.4%, interquartile range (IQR): 94.9%-99.8%], HR (82.0%, IQR: 28.9%-98.2%), NLOD (12.6%, IQR: 5.2%-63.4%), and CG (16.2%, IQR: 6.6%-20.1%) (P < 0.0001). Median levels of CA 19-9 were within the normal range in all groups (standard clinical cut-off of 37 U/mL). Within HR, individuals with a positive history of cancer had higher median levels of GPC1⁺ crExos (97.9%; IQR: 61.7%-99.5%), compared to those without (59.7%; IQR: 26.3%-96.4%), despite no statistical significance (P = 0.21). Pancreatic cysts with WF/HRS were statistically associated with higher median levels of GPC1⁺ crExos (99.6%; IQR: 97.6%-99.8%) compared to those without (96.5%; IQR: 81.3%-99.5%) (P = 0.011), presenting an area under the receiver operating characteristic curve value of 0.723 (sensitivity 75.0% and specificity 67.7%, using a cut-off of 98.5%; P = 0.012).

CONCLUSION

GPC1⁺ crExos may act as biomarker to support the diagnosis and stratification of PDAC precursor lesions, and in signaling individuals with genetic predisposition in the absence of EUS abnormalities.

Endoscopic Ultrasound Through-The-Needle Biopsy of Pancreatic Cysts: Toward Procedure Standardization

BACKGROUND AND AIMS

EUS-guided through-the-needle microforceps biopsy (EUS-TTNB) was introduced as a new diagnostic tool to establish pancreatic cyst histotype and help to better risk stratify the patients. The aim of this study was to describe the technical success, diagnostic yield, and adverse events of through-the-needle biopsy and discuss the technique variations, focusing on future procedure standardization.

METHODS

We performed a prospective single-center study including patients with presumed mucinous cysts harboring worrisome features or indeterminate cyst type on imaging, submitted to EUS-TTNB using Moray® microforceps between March 2018 and September 2021. Specimens were processed as a cell-block.

RESULTS

We included 40 patients. Technical success was 97.5%. The diagnostic yield was 72.5% for TTNB whereas for cyst fluid cytology/analysis it was 27.5%. Moreover, without TTNB 5 mucinous lesions would not have been diagnosed. TTNB had a sensitivity of 76% and a specificity of 91%, while FNA cytology had a sensitivity and specificity of 35% and 91%, respectively. Moreover for IPMN lesions, subtyping was possible in 63% of cases. TTNB resulted in change in clinical management in 20% of patients. We registered three adverse events: 2 self-limited intracystic bleeding and 1 patient with abdominal pain not associated with pancreatitis.

CONCLUSION

TTNB proved superior to cyst fluid analysis and cytology for the definition of cyst histotype and mucinous cyst diagnosis with acceptable risk profile. Further studies should explore the best steps for procedure standardization.

Exosomal glypican-1 discriminates pancreatic ductal adenocarcinoma from chronic pancreatitis

BACKGROUND AND AIMS

Pancreatic ductal adenocarcinoma (PDAC) diagnosis can be difficult in a chronic pancreatitis (CP) background, especially in its mass forming presentation. We aimed to assess the accuracy of glypican-1-positive circulating exosomes (GPC1+crExos) to distinguish PDAC from CP versus the state-of-the-art CA 19-9 biomarker.

METHODS

This was a unicentric prospective cohort. Endoscopic ultrasound with fine-needle aspiration or biopsy and blood tests (GPC1+crExos and serum CA 19-9) were performed.

RESULTS

The cohort comprised 60 PDAC and 29 CP (7 of which mass forming - MF) patients. Median levels of GPC1+crExos were significantly higher in PDAC (99.7%) versus CP (28.4%; p<0.0001) with an AUROC of 0.96 with 98.3% sensitivity and 86.2% specificity for a cut-off of 45.0% (p<0.0001); this outperforms CA 19-9 AUROC of 0.82 with 78.3% sensitivity and 65.5% specificity at a cut-off of 37 U/mL (p<0.0001). The superiority of% GPC1+crExos over CA 19-99 in differentiating PDAC from CP was observed in both early (stage I) and advanced tumors (stages II-IV).

CONCLUSION

Levels of GPC1+crExos coupled to beads enable differential diagnosis between PDAC and CP including its mass-forming presentation.

Solid Pseudopapillary Neoplasm of the Pancreas: Unfolding an Intriguing Condition

Pancreatic cancer is one of the most lethal malignant neoplasms, with a 1-year survival rate after diagnosis of 24%, and a 5-year survival rate of only 9%. While this illustrates the behavior of its main histologic type - ductal adenocarcinoma, there are other histologic subtypes of pancreatic cancer that can harbor excellent prognosis. Solid pseudopapillary neoplasm, described as a rare low-grade malignant neoplasm by the World Health Organization, is the best example of that, having an overall 5-year survival rate of about 97%. Not only the prognosis, but everything about this entity is unique: its histogenesis, epidemiology, presentation, imaging characteristics, cytology features, immunohistochemical profile, and treatment. This explains the urge to improve our understanding about this entity and thus our ability to accurately recognize and manage it. Having this in mind, this article aims to summarize the most relevant topics regarding this entity.

Extracellular Vesicles from Pancreatic Cancer Stem Cells Lead an Intratumor Communication Network (EVNet) to fuel tumour progression

OBJECTIVE

Intratumor heterogeneity drives cancer progression and therapy resistance. However, it has yet to be determined whether and how subpopulations of cancer cells interact and how this interaction affects the tumour.

DESIGN

We have studied the spontaneous flow of extracellular vesicles (EVs) between subpopulations of cancer cells: cancer stem cells (CSC) and non-stem cancer cells (NSCC). To determine the biological significance of the most frequent communication route, we used pancreatic ductal adenocarcinoma (PDAC) orthotopic models, patient-derived xenografts (PDXs) and genetically engineered mouse models (GEMMs).

RESULTS

We demonstrate that PDAC tumours establish an organised communication network between subpopulations of cancer cells using EVs called the EVNet). The EVNet is plastic and reshapes in response to its environment. Communication within the EVNet occurs preferentially from CSC to NSCC. Inhibition of this communication route by impairing Rab27a function in orthotopic xenographs, GEMMs and PDXs is sufficient to hamper tumour growth and phenocopies the inhibition of communication in the whole tumour. Mechanistically, we provide evidence that CSC EVs use agrin protein to promote Yes1 associated transcriptional regulator (YAP) activation via LDL receptor related protein 4 (LRP-4). Ex vivo treatment of PDXs with antiagrin significantly impairs proliferation and decreases the levels of activated YAP.Patients with high levels of agrin and low inactive YAP show worse disease-free survival. In addition, patients with a higher number of circulating agrin+ EVs show a significant increased risk of disease progression.

CONCLUSION

PDAC tumours establish a cooperation network mediated by EVs that is led by CSC and agrin, which allows tumours to adapt and thrive. Targeting agrin could make targeted therapy possible for patients with PDAC and has a significant impact on CSC that feeds the tumour and is at the centre of therapy resistance.

Retrospective analysis of the outcomes of endoscopic submucosal dissection for the diagnosis and treatment of subepithelial lesions in a center with high expertise

Background

Use of endoscopic submucosal dissection (ESD) for the diagnosis and treatment of subepithelial lesions (SELs) is limited in the West, and the best approach for these lesions is still debated. In this study we describe our experience regarding the usefulness, safety and outcomes of ESD for SELs.

Method

We performed a retrospective analysis of ESD in the diagnosis and treatment of SELs between November 2010 and February 2021.

Results

A total of 634 ESDs were reviewed. Fifty-five (9%) were performed in SELs, 6 in the esophagus, 34 in the stomach, and 15 in the rectum. ESD was technically successful in 53 lesions (96%). Most of them (82%) had previous endoscopic ultrasound evaluation, but only 20% had a histological diagnosis previous to the ESD. Neuroendocrine tumors, gastrointestinal stromal tumors, and granular cell tumors accounted for 38% of the procedures, with a 100% rate of en bloc resection and 65% of R0 resection; the main criterion for non-curative resection was a deep positive margin, and none of the patients treated with complementary surgery had lesions on the gastrointestinal wall. Most of the procedures (62%) were performed in lesions with very low malignant potential, providing the definitive diagnosis of SELs where the previous diagnostic workup was inconclusive. We had a total of 2 delayed bleedings and 1 perforation, all treated endoscopically.

Conclusion

Our real-life experience showed that ESD can be an effective and safe diagnostic tool for undetermined SELs, as well as an effective treatment for neoplastic SELs with malignant potential.

The role of endoscopic submucosal dissection in the management of gastric inflammatory fibroid polyps: a single-center experience

BACKGROUND AND AIM

Gastric inflammatory fibroid polyps constitute only 0.1% of all gastric polyps. They are usually asymptomatic and are most often found in the antrum. These lesions are in the majority of cases amenable to resection by snare polypectomy. However, there are rare case reports of gastric IFP requiring resection by endoscopic submucosal dissection. This study aimed to evaluate the effectiveness and safety of endoscopic submucosal dissection in the management of gastric inflammatory fibroid polyps not amenable to resection with snare polypectomy because of large size and/or deep subepithelial engagement.

METHODS

A retrospective study of all consecutive patients who undergone endoscopic submucosal dissection for gastric inflammatory fibroid polyps between January 2011 and December 2020 was performed.

MAJOR RESULTS

There were 9 cases of gastric inflammatory fibroid polyps resected by endoscopic submucosal dissection. Most patients were female (7/9) with a mean age of 62.2 years. All gastric inflammatory polyps were described as solitary antral subepithelial lesions with mean diameter of 16.7 mm. Helicobacter pylori was detected in only one patient. At endoscopic ultrasound, these lesions were uniformly described as well-circumscribed, homogeneous lesions located at muscularis mucosa and submucosa without invasion of muscularis propria. All lesions were successfully resected en-bloc by endoscopic submucosal dissection and complete resection with free margins was obtained in 8/9 specimens. Adverse events were reported in 2/9 cases including one case of intra-procedural bleeding successfully controlled with hemostatic clips and one case of aspiration pneumonia that evolved favorably. Mean follow-up duration was 33.7 months (range 0-120) and no delayed complications or cases of recurrence were detected during follow-up.

CONCLUSIONS

Endoscopic submucosal dissection appears to be a safe and effective approach for resection of gastric inflammatory fibroid polyps that present as large subepithelial lesions if performed by experienced endoscopists after adequate characterization by endoscopic ultrasound with high rates of technical success and low recurrence rates. .

Abstract 2010: Pancreatic cancer stem cell exosomes drive a hierarchical intratumor communication network that fuels disease progression through hippo pathway inhibition

Intra-tumor heterogeneity represents a major challenge for cancer treatment. Resistance to therapy and tumorigenic ability varies greatly between distinct subpopulations of cancer cells. Intercellular communication is critical to establish a cooperative environment that maintains tumor heterogeneity and potentiates disease progression. However, how subpopulations of cancer cells interact to support tumor progression is not fully understood. Exosomes have the potential to re-educate recipient cells through the delivery of their cargo, emerging as the main mediators of intercellular communication. Here we demonstrate that subpopulations of pancreatic cancer cells use exosomes to establish a hierarchical and dynamic communication network, the ExoNet. Exosomes from cancer stem cells (CSC) are preferentially taken up by non-CSC (NCSC). Targeted inhibition of CSC exosomes in PDAC orthotopic, genetically engineered and patient-derived xenograft mouse models is sufficient to impair tumor growth and metastasis establishment. A comprehensive comparative proteomic analysis of exosomes derived from distinct subpopulations of pancreatic ductal adenocarcinoma (PDAC) human cell lines identified a significant enrichment of Agrin in CSC exosomes. Blocking exosomes secretion and downregulating Agrin in CSCs significantly diminishes YAP nuclear localization in receiving cells, indicating that CSC exosomes contribute for Hippo pathway inactivation. Agrin+ circulating exosomes correlate with tumor burden in PDAC patients, and most importantly correlate with CD133+ circulating exosomes, indicating that circulating Agrin+ exosomes are from CSC origin. Longitudinal analysis of circulating Agrin+ exosomes in PDAC patients predicts disease progression and response to therapy. Our study describes a novel role of cancer exosomes in the interplay between subpopulations of cancer cells promoting tumor progression. We identified Agrin as a potential non-invasive biomarker to monitor disease progression and predict treatment response.

Citation Format: Carolina F. Ruivo, Nuno Bastos, Ines Batista, Barbara Adem, Cecilia Duraes, Carlos A. Melo, Francisco J. Campos-Laborie, Pedro Moutinho-Ribeiro, Barbara Mourão, Marília Cravo, Guilherme Macedo, Fátima Carneiro, Tony Kouzarides, Raghu Kalluri, Jose C. Machado, Sonia Melo. Pancreatic cancer stem cell exosomes drive a hierarchical intratumor communication network that fuels disease progression through hippo pathway inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2010.

Use of suction during endoscopic ultrasound-guided fine needle biopsy of solid pancreatic lesions with a Franseen-tip needle: a pilot comparative trial

Background and study aims  The utility of suction during endoscopic ultrasound (EUS) fine-needle biopsy (FNB) using Franseen-tip needle remains unclear and has not been evaluated in randomized trials. We designed a randomized crossover trial to compare the diagnostic yield during EUS-FNB using a 22G Franseen-tip needle, with and without standard suction. Patients and methods  Consecutive patients undergoing EUS-guided sampling of solid pancreatic lesions were recruited. A minimum of two passes were performed for each case: one with 20-mL syringe suction (S+) and another without (S-). The order of passes was randomized and the pathologist blinded. The endpoints were the diagnostic yield and the impact of blood contamination in the diagnosis. Results  Fifty consecutive patients were enrolled. The overall diagnostic accuracy was 84 %. A diagnosis of malignancy was obtained in 70 samples: 36 in the S+group and 34 in the S-group. A statistically significant difference was seen in the diagnostic accuracy (S+: 78 % vs. S-: 72 %, P  < 0.01) and blood contamination (S+: 68 %; S-: 44 %, P  < 0.01). The sensitivity, specificity, negative likelihood ratio and positive likelihood ratio for S+vs. S-samples were 76.6 % vs. 73.9 %, 100 % vs. 100 % and 0.23 vs. 0.26, NA vs NA, respectively. A negative impact of blood contamination in the overall diagnostic yield wasn't seen, even in samples where suction was used (OR 0.36, P  = 0.15) Conclusions  We found a higher diagnostic yield with the use of suction. It was associated with a higher degree of sample blood contamination that did not affect the diagnostic performance.

Endoscopic Ultrasound-Guided Celiac Plexus Interventions

Abdominal pain related to pancreatic disease is often extremely disabling. Endoscopic ultrasound (EUS)-guided celiac plexus block (CPB) is used to control pain associated with chronic pancreatitis. EUS-guided celiac plexus neurolysis (CPN) is typically used to reduce pain associated with pancreatic cancer and can be considered early at the time of diagnosis of inoperable disease. EUS-guided celiac plexus interventions have been shown to be significantly effective in pancreatic pain relief, which is achieved in approximately 70-80% of patients with pancreatic cancer and in 50-60% of those with chronic pancreatitis. Serious complications from CPB and CPN are rare. Most frequent adverse events are diarrhoea, orthostatic hypotension, and a transient increase in abdominal pain. In this article, the Portuguese Group for Ultrasound in Gastroenterology (GRUPUGE) presents an updated perspective of the potential role of EUS-guided celiac plexus interventions, addressing the selection criteria and technical issues of different techniques and analysing recent data on their safety and efficacy.

Development of an Online App to Predict Post-Endoscopic Retrograde Cholangiopancreatography Adverse Events Using a Single-Center Retrospective Cohort

INTRODUCTION

Endoscopic retrograde cholangiopancreatography (ERCP) is a technically demanding procedure with a high risk for adverse events (AEs).

AIM

evaluate patient- and procedure-related risk factors for ERCP-related AEs and develop an online app to estimate risk of AEs.

METHODS

retrospective study of 1,491 consecutive patients who underwent 1,991 ERCPs between 2012 and 2017 was conducted. AEs definition and severity were classified according to most recent ESGE guidelines. Each variable was tested for association with occurrence of overall AEs, post-ERCP pancreatitis (PEP) and cholangitis. For each outcome, 2 regression models were built, from which an online Shiny-based app was created.

RESULTS

Overall AE rate was 15.3%; in 19 procedures, >1 AE occurred. Main post-ERCP AE was PEP (7.5%), followed by cholangitis (4.9%), bleeding (1.3%), perforation (1%), cardiopulmonary events (0.9%), and cholecystitis (0.3%). Seventy-eight percent of AEs were mild/moderate; of severe (n = 55) and fatal (n = 20) AEs, more than half were related to infection, cardiac/pulmonary AEs, and perforation. AE-related mortality rate was 1%. When testing precannulation, procedural covariates, and ERCP findings, AE occurrence was associated with age (odds ratio [OR] 0.991), previous PEP (OR 2.198), ERCP complexity grade III/IV (OR 1.924), standard bile duct cannulation (OR 0.501), sphincterotomy (OR 1.441), metal biliary stent placement (OR 2.014), periprocedural bleeding (OR 3.024), and biliary duct lithiasis (OR 0.673).

CONCLUSION

Our app may allow an optimization of the patients' care, by helping in the process of decision-making, not only regarding patient or endoscopist's selection but also definition of an adequate and tailored surveillance plan after the procedure.

Endoscopic Ultrasound-Guided Ablation of Focal Pancreatic Lesions: The GRUPUGE Perspective

Focal pancreatic lesions include a heterogeneous group of solid and cystic lesions, with different natures and variable clinical, imagiological, and pathological characteristics. Several endoscopic ultrasound (EUS)-guided ablative techniques have been tested during the last decade for the treatment of these pancreatic lesions, mostly consisting of the injection of ablative agents and, more recently, radiofrequency ablation. The most encouraging EUS-guided ablation outcomes are being reached in the treatment of some pancreatic cystic neoplasms and small (≤2 cm) pancreatic neuroendocrine tumours (pNETs). Data supporting a potential role of ablative therapies in the treatment of pancreatic ductal adenocarcinoma is still lacking. In this article, GRUPUGE presents an updated perspective of the potential role of EUS-guided ablation for the treatment of pancreatic cystic neoplasms and pNETs, addressing the selection criteria and technical issues of different techniques and analysing recent data on their safety and efficacy.

GRUPUGE Perspective: Endoscopic Ultrasound-Guided Drainage of Peripancreatic Collections

Pancreatic and peripancreatic collections (PPC) are a known complication of acute pancreatitis. They are categorized into four types of collection: (1) acute peripancreatic fluid collection, (2) pseudocyst, (3) acute necrotic collection and (4) walled-off necrosis. Most PPC resolve spontaneously or are persistent but asymptomatic. Intervention is needed in a minority of patients with infected or symptomatic collection. Endoscopic ultrasound-guided transmural drainage is currently the first-line treatment option for PPC management. It has shown great technical and clinical success, similar to percutaneous or surgical approaches, but with lower morbidity and costs and better quality of life. In this review article, the GRUPUGE presents an updated perspective on the potential role of endoscopic ultrasound-guided drainage of peripancreatic collections, addressing the selection criteria and the technical issues of different techniques and analysing emerging data on their efficacy and safety.

GRUPUGE PERSPECTIVE: Endoscopic Ultrasound-Guided Biliary Drainage

Endoscopic ultrasound-guided biliary drainage (EUS-BD) is an alternative to percutaneous and surgical drainage in bile duct obstruction when endoscopic retrograde cholangiopancreatography fails. EUS-BD can be achieved with several techniques, including EUS-guided hepaticogastrostomy (HGS), anterograde transpapillary stent placement, choledochoduodenostomy (CDS), and rendez-vous technique. Lately, with increased experience and development of directed equipment, elevated technical and clinical success as well of lower adverse event rates have been reported. In this article, GRUPUGE presents an updated perspective of the potential role of EUS-guided biliary drainage, addressing the selection criteria and technical issues of different techniques and analyzing recent data on their safety and efficacy.

GRUPUGE Perspective: Endoscopic Ultrasound-Guided Fine-Needle Tattooing and Fiducial Placement in Pancreatic Cancer

In the last 2 decades, endoscopic ultrasound (EUS) has become an important procedure for the diagnosis and management of several pancreatic diseases, including pancreatic cancer. This article presents two recently developed EUS-guided techniques for the management of pancreatic cancer: fine-needle tattooing and fiducial placement. Preoperative EUS-guided fine-needle tattooing of small pancreatic tumors helps in precise localization of these lesions during surgery, potentially ensuring adequate margins of resection while preserving healthy pancreatic tissue. In pancreatic cancer patients planned for imaging-guided radiation therapy, EUS-guided fiducial placement improves the accuracy of target delineation during stereotactic body radiation therapy (SBRT). Hydrogel, a new injectable liquid with multimodal visibility recently approved as a liquid fiducial, is currently under investigation in pancreatic head cancer as an EUS-injected spacer to potentially reduce SBRT gastrointestinal wall toxicity. In this article, GRUPUGE presents an updated perspective of these two EUS-guided techniques, addressing their current clinical applications and technical aspects and analyzing existing data on their efficacy and safety.

Exosomal glypican-1 for risk stratification of pancreatic cystic lesions: A case of pathological progression in the absence of any suspicious imaging finding

The clinical management of patients with pancreatic cystic lesions is of utmost importance to identify those at high risk for pathological progression. Current recommendations are guided by clinical presentation and radiologic criteria, but the results fall short for a disease that the only curative option is surgical resection. There is an urgent need for the introduction of biomarkers that can help in risk assessment of such lesions. We report a case of a pancreatic cystic lesion without imagiological findings suggestive of advanced disease, and high levels of a circulating biomarker, glypican-1 (GPC-1), which parallel those of patients with pancreatic cancer. One year after, the patient revealed malignant progression at follow-up. Our report is unprecedented in the literature. It describes a clinical case in which a biomarker was positive for a patient that only showed progression one year after its detection. This clinical information goes beyond the current knowledge in the field because it shows that the introduction of liquid biopsy and biomarkers is a highly promising clinical tool for the non-invasive assessment of pancreatic cancer precursor lesions, ultimately increasing the rate of patients eligible for surgical resection.

Clube Português do Pâncreas Recommendations for Chronic Pancreatitis: Medical, Endoscopic, and Surgical Treatment (Part II)

Chronic pancreatitis (CP) is a complex disease that should be treated by experienced teams of gastroenterologists, radiologists, surgeons, and nutritionists in a multidisciplinary environment. Medical treatment includes lifestyle modification, nutrition, exocrine and endocrine pancreatic insufficiency correction, and pain management. Up to 60% of patients will ultimately require some type of endoscopic or surgical intervention for treatment. However, regardless of the modality, they are often ineffective unless smoking and alcohol cessation is achieved. Surgery retains a major role in the treatment of CP patients with intractable chronic pain or suspected pancreatic mass. For other complications like biliary or gastroduodenal obstruction, pseudocyst drainage can be performed endoscopically. The recommendations for CP were developed by Clube Português do Pâncreas (CPP), based on literature review to answer predefined topics, subsequently discussed and approved by all members of CPP. Recommendations are separated in two parts: "chronic pancreatitis etiology, natural history, and diagnosis," and "chronic pancreatitis medical, endoscopic, and surgical treatment." This abstract pertains to part II.

Endoscopic ultrasound in pancreatic cancer treatment: Facts and hopes

Pancreatic ductal adenocarcinoma is one of the most common causes of cancer-related deaths. Since most patients present with advanced disease, its prognosis is dismal. New and more effective therapeutic strategies are needed. Endoscopic ultrasound is currently an indispensable tool for the diagnosis and staging of pancreatic ductal adenocarcinoma. In recent years, endoscopic ultrasound has evolved to become also a therapeutic procedure. On one hand, the role of endoscopic ultrasound in the management of pancreatic cancer-related symptoms (pain, obstructive jaundice, and gastric outlet obstruction) is now well established. On the other hand, its use as a mean to the delivery of anti-tumor therapies (injecting anti-tumor agents, assisting in radiotherapy, and guiding ablative therapies) is still mostly experimental, despite growing evidence supporting its feasibility, safety and efficacy.

Clube Português do Pâncreas Recommendations for Chronic Pancreatitis: Etiology, Natural History, and Diagnosis (Part I)

Chronic pancreatitis (CP) is a heterogeneous disease, with different causes and often a long delay between onset and full classic presentation. Clinical presentation depends on the stage of the disease. In earlier stages, recurrent episodes of acute pancreatitis are the major signs dominating clinical presentation. As the inflammatory process goes on, less acute episodes occur, and pain adopts different aspects or may even disappear. After 10-15 years from onset, functional insufficiency occurs. Then, a classic presentation with pain and pancreatic exocrine and endocrine insufficiency appears. Diagnosis remains challenging in the early stages of the disease, as its initial presentation is usually ill-defined and overlaps with other digestive disorders. Computed tomography and magnetic resonance cholangiopancreatography should be the first choice in patients with suspected CP. If the results are normal or equivocal but still there is a high suspicion of CP, the next option should be endoscopic ultrasound. Endoscopic retrograde cholangiopancreatography is mainly a therapeutic technique, and for the diagnostic purpose should only be used when all other imaging modalities and pancreatic function tests have been exhausted. Indirect tests are used to quantify the degree of insufficiency in already-established late CP. Recommendations on CP were developed by Clube Português do Pâncreas (CPP), based on literature review to answer predefined topics, subsequently discussed and approved by all members of CPP. Recommendations are separated in two parts: "chronic pancreatitis etiology, natural history, and diagnosis," and "chronic pancreatitis medical, endoscopic, and surgical treatment." This abstract pertains to part I.

Early pancreatic cancer - The role of endoscopic ultrasound with or without tissue acquisition in diagnosis and staging

Pancreatic cancer (PC) is one of the deadliest cancers with a 5-year overall survival of less than 6%. Due to its insidious clinical course and unspecific symptoms, the diagnosis is usually late, with only 15-20% patients presenting with potentially curable disease. It is, therefore, extremely important to identify patients with PC at early stages of the disease when tumors may be amenable to surgical resection. For unresectable and borderline resectable PC it is consensual to perform a biopsy to have a cyto/histological confirmation of malignancy before treatment. However, for patients presenting with promptly resectable disease, the role of biopsy is more debatable. There are, in the literature, arguments both for and against the usefulness of a preoperative biopsy. Endoscopic ultrasound (EUS) is an important technique assisting in the diagnosis and staging of PC. EUS-guided tissue acquisition is a well-established tool to demonstrate the malignant nature of a pancreatic lesion. This review focuses on the role of EUS in the diagnosis and staging of PC, and highlights the controversy related to the role of EUS-guided tissue acquisition in the preoperative assessment of patients presenting with promptly resectable tumors (early PC).

Gastrointestinal stromal tumors in the imatinib era: 15 years' experience of a tertiary center

Gastrointestinal stromal tumors (GISTs) were associated with a disease free survival rate of disease of 50% at 5 years, but the actual natural history since the advent of imatinib is poorly described. Our objective was to evaluate the evolution in the treatment and prognosis of patients with GISTs since the start of imatinib. Retrospective analysis of GISTs diagnosed between January 2000 and June 2015 in a Portuguese large volume center. We included 131 patients, 55% female, with a mean age of 64±14 years, followed for a median of 30 months; 64% of cases had gastric involvement; 92% of the tumors were c-Kit positive; 95% of patients were operated. Imatinib was initiated in 25% of patients, as adjuvant therapy in 69%; 75% reported adverse effects, and 16% developed resistance. The recurrence rate was 4%, and was associated with age at diagnosis (P=0.037), tumor size (P=0.028), presence of metastases (P=0.019) and high-risk lesions (P=0.036). Survival at 1, 3 and 5 years was 87%, 71% and 61%, respectively. One year's mortality was significantly associated with tumor size (P=0.021), stage IV at diagnosis (P=0.003), non-complete resection (P=0.002) and palliation with imatinib (P=0.035). Similar associations were observed at the 3 and 5 years. In the imatinib era there is an increased long-term survival in comparison with previous epidemiological data, and reduced recurrence rates. In more advanced cases survival remains limited in the short term.

Pancreatic Cancer Diagnosis and Management: Has the Time Come to Prick the Bubble?

Pancreatic cancer (PC) is associated with poor prognosis and very dismal survival rates. The most effective possibility of cure is tumor resection, which is only possible in about 15% of patients diagnosed at early stages of disease progression. Recent whole-genome sequencing studies pointed genetic alterations in 12 core signaling pathways in PC. These observations hint at the possibility that the initial mutation in PC might appear nearly 20 years before any symptoms occur, suggesting that a large window of opportunity may exist for early detection. Biomarkers with the potential to identify pre-neoplastic disease or very early stages of cancer are of great promise to improve patient survival. The concept of liquid biopsy refers to a minimally invasive sampling and analysis of liquid biomarkers that can be isolated from body fluids, primarily blood, urine and saliva. A myriad of circulating molecules may be useful as tumor markers, including cell-free DNA (cfDNA), cell-free RNA (cfRNA), circulating tumor cells (CTC), circulating tumor proteins, and extracellular vesicles, more specifically exosomes. In this review, we discuss with more detail the potential role of exosomes in several aspects related to PC, from initiation to tumor progression and its applicability in early detection and treatment. Exosomes are small circulating extracellular vesicles of 50-150 nm in diameter released from the plasma membrane by almost all cells and exhibit some advantages over other biomarkers. Exosomes are central players of intercellular communication and they have been implicated in a series of biological process, including tumorigenesis, migration and metastasis. Several exosomal microRNAs and proteins have been observed to distinguish PC from benign pancreatic diseases and healthy controls. Besides their possible role in diagnosis, understanding exosomes functions in cancer has clarified the importance of microenvironment in PC progression as well as its influence in proliferation, metastasis and resistance to chemotherapy. Increasing knowledge on cancer exosomes provides valuable insights on new therapeutic targets and can potentially open new strategies to treat this disease. Continuous research is needed to ascertain the reliability of using exosomes and their content as potential biomarkers, so that, hopefully, in the near future, they will provide the opportunity for early diagnosis, treatment intervention and increase survival of PC patients.

Endoscopic Retrograde Cholangiopancreatography and Endoscopic Ultrasound: To Be One Traveler in Converging Roads

Background

Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) were initially introduced into the world of gastroenterology as purely diagnostic procedures. With progressive evolution of intervention, both these techniques conquered fields in the treatment of many conditions that had once been exclusively surgical domains. Nowadays, more and more clinical situations have an indication to perform both EUS and ERCP, and these two techniques are frequently required at the same time for the same patient. More than competitors, ERCP and EUS are truly complementary, with great ability for mutual aid. They share their main indications, equipment, accessories, and main technical gestures.

Objectives and Methods

We review the major indications to perform both techniques, sequentially or complementarily, describe the common things that these two techniques essentially share, and discuss the ERCP-EUS single session. Also, the issues of learning curves and education of upcoming biliopancreatic endoscopists are highlighted.

Conclusion

In recent years the complementation between ECRP and EUS has been growing both from a diagnostic and a therapeutic point of view, allowing optimization of the use of these techniques and the creation of a more systematized approach of patients with biliopancreatic pathology. Endoscopists with experience in both techniques will be increasingly important, suggesting a parallel formation in the training plans of future endoscopists with interest in the area.

Demystifying endoscopic retrograde cholangiopancreatography (ERCP) during pregnancy

BACKGROUND

For many years, ERCP was avoided in pregnancy given the concerns regarding the adverse effects that, with special focus on radiation, could occur in the developing fetus. However, the postponement or rejection of ERCP in pregnant women, may lead to a higher risk for mother and fetus, especially when the indication is unequivocal, namely cholangitis, biliary pancreatitis and symptomatic choledocholithiasis.

SUMMARY AND KEY MESSAGES

This review aims to summarize the scarce literature on the subject in order to plan ERCP in pregnancy with the highest safety. The use of techniques that reduce radiation and increase the protection of pregnant women allow radiation levels far below the safety limits. We also discuss the various alternatives of ERCP without radiation. EUS can eliminate the need for ERCP with doubtful choledocholithiasis and plan the best approach in those with previous evidence. The possibility of performing "ERCP" with a linear echoendoscope uniquely under ultrasound control has been described. Conversely, the two-step strategy (initial sphincterotomy with stent placement without fluoroscopy and after delivery, ERCP with lithiasis extraction) proved to be safe obviating fluoroscopy. In conclusion, ERCP can be performed in pregnancy safely and effectively with minimal radiation or even no-radiation at all.

Pancreatic cancer screening: Still a delusion?

Pancreatic adenocarcinoma represents the fourth most common cause of cancer mortality and death due to pancreatic cancer (PC) have increased since 2003. Its incidence has also raised about 30% in the past decade and it is expected to become the second cause of cancer mortality by 2020 in the USA. Most PC present with metastatic disease and improvements in treatment outcomes for this group have been disappointing. These observations support the idea that screening to identify patients at an earlier stage might be an important strategy in improving overall PC outcomes. Many protocols have been tested, nevertheless, by now there is no effective screening program. Given the overall low incidence of disease and the current lack of accurate, inexpensive and noninvasive screening tests, the consensus is that widespread population-based screening for PC in the general population or in patients with only one affected first-degree relative is neither practicable nor indicated in most countries. However, a different scenario is screening patients with higher risk for PC, most of them with hereditary conditions predisposing the development of this neoplasia. In fact, some guidelines are now available helping to select these individuals at risk and to screen them, in order to achieve early detection of PC.

Degenerate intraductal papillary mucinous carcinoma with fish-mouth appearance of the papilla

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Self-expanding metal stents in postoperative esophageal leaks

BACKGROUND

Postoperative esophageal leaks have a high morbidity and mortality. Self-expanding metal stents (SEMS) have been used as an alternative to re-operation.

AIM

Evaluating predictors of success of SEMS in postoperative esophageal leaks.

METHODS

Retrospective study of patients with postoperative esophageal leaks referred for SEMS placement in a reference center during a period of 3 years. Technical success was defined as closure of the leak in barium swallow at 15 days. Clinical success was considered as endoscopic and/or radiographic confirmation of closure after stent removal.

RESULTS

Thirteen patients placed SEMS. Median follow-up was 58 days. Leaks had a median size of 20 mm. Time between surgery and SEMS placement was 20 days. One patient died 2 days after SEMS placement and one had worsening of the fistula after SEMS expansion. Time till stent migration was 9 days. Technical success was achieved in 9 of 11 patients, with clinical success without recurrence in 5 patients. All leaks with less than 20 mm were solved endoscopically. Technical and clinical success was higher when time between surgery and SEMS placement was lower, even though without statistical significance (respectively, p = 0.228 and 0.374). In the 8 patients who died during follow-up, median survival was 59 days.

CONCLUSIONS

Technical success of SEMS was higher than 80%; however, due to high morbidity and mortality, only 45% of patients had their stent removed. Lower time from diagnosis to SEMS placement and leak size less than 20 mm may be associated with better results.

Outcome and risk factors assessment for adverse events in advanced esophageal cancer patients after self-expanding metal stents placement

Self-expanding metal stents (SEMS) are the treatment of choice for advanced esophageal cancers. Literature is scarce on risk factors predictors for adverse events after SEMS placement. Assess risk factors for adverse events after SEMS placement in advanced esophageal cancer and evaluate survival after SEMS placement. Cross-sectional study of patients with advanced esophageal cancer referred for SEMS placement, during a period of 3 years. Ninety-seven patients with advanced esophageal cancer placed SEMS. Adverse events were more common when tumors were located at the level of the distal esophagus/cardia (47% vs 23%, P = 0.011, OR 3.1), with statistical significance being kept in the multivariate analysis (OR 3.1, P = 0.018). Time until adverse events was lower in the tumors located at the level of the distal esophagus/cardia (P = 0.036). Survival was higher in patients who placed SEMS with curative intent (327 days [126-528] vs. 119 days [91-147], P = 0.002) and in patients submitted subsequently to surgery compared with those who did just chemo/radiotherapy or who did not do further treatment (563 days [378-748] vs. 154 days [133-175] vs. 46 days [20-72], P < 0.001). Subsequent treatment kept statistical significance in the multivariate analysis (HR 3.4, P < 0.001). SEMS allow palliation of dysphagia in advanced esophageal cancer and are associated with an increased out-of-hospital survival, as long as there are conditions for further treatments. Tumors located at the level of the distal esophagus/cardia are associated with a greater number of adverse events, which also occur earlier.

Endoscopic management of late complication of blunt traumatic total pancreatic transection

An 11-year-old girl was admitted elsewhere due to severe abdominal pain after a fall with abdominal blunt trauma. CT-scan showed total pancreatic transection of the distal body with suspected injury of main pancreatic duct.

Interobserver agreement of EUS elastography in the evaluation of solid pancreatic lesions

Background and Objectives:

Previous reports assessing the reproducibility of endoscopic ultrasound elastography (EUS-E) in evaluation of solid pancreatic lesions (SPL) involved only experienced endosonographers. We aimed to assess the interobserver agreement (IOA) of EUS-E in the evaluation of SPL by endoscopists with different levels of experience in EUS and EUS-E.

Materials and Methods:

A cross-sectional observational multicenter study was designed and included 11 endoscopists who were divided into four groups: Group A (long experience in EUS and EUS-E); Group B (short experience in EUS and EUS-E); Group C (long experience in EUS and no experience in EUS-E); and Group D (no experience in EUS or EUS-E). The observers independently classified the patterns of 60 video sequences of EUS-E, after a 20-min training session. For each group, we calculated IOA (kappa statistic, κ) of EUS-E and the diagnostic accuracy of EUS-E for pancreatic malignancy, by comparing the pattern of EUS-E indicative of malignancy (heterogeneous or homogenous blue) with the final diagnosis.

Results:

The overall IOA was moderate (κ = 0.42; 95% confidence interval (CI) 0.33-0.52). The IOA of Group A (κ = 0.80; 95% CI 0.65-1.00) was significantly higher than that of Groups B (κ = 0.54; 95%CI 0.40-0.71), C (κ = 0.54; 95%CI 0.39-0.68), and D (κ = 0.28; 95%CI 0.14-0.40). IOA of Groups B and C was not significantly different, but it was significantly higher than that of Group D. The diagnostic accuracy of Group A (area under the curve under summary receiver operating characteristic (AUROC) = 0.83; 95%CI 0.75-0.90) was not significantly different from that of Group B (AUROC = 0.77; 95%CI 0.71-0.83), but it was significantly higher than that of Groups C (AUROC = 0.74; 95%CI 0.67-0.81) and D (AUROC = 0.74; 95%CI 0.67-0.81). No significant difference was seen between Groups B, C, and D for diagnostic accuracy.

Conclusion:

EUS-E is reproducible in the evaluation of SPL, even between endoscopists with no or limited experience in EUS and/or EUS-E. Reproducibility and diagnostic accuracy increase with experience in EUS and EUS-E.

Outcome of endoscopic self-expandable metal stents in acute malignant colorectal obstruction at a tertiary center

BACKGROUND

Malignant colorectal obstruction (MCRO) by advanced colonic cancer occurs in 8-13% of colonic cancer patients. Emergent surgery carries a high mortality and morbidity risk. Endoscopic self-expanding metal stents (SEMS) may be used in acute MCRO.

AIM

Evaluate clinical outcome of SEMS in acute MCRO and efficacy of SEMS placement considering fluoroscopy guidance.

METHODS

Retrospective study of patients with acute MCRO that placed SEMS in a 3 years period.

RESULTS

SEMS were placed in 47 patients, followed-up for a median time of 150 days. The intent of stenting was bridge to definitive surgery in 40% of the patients (n = 19) and palliation in the remaining 60% (n = 28). The location of the tumor did not influence the presence of lymph node involvement (p = 0.764) nor metastasis (p = 0.885). Mortality rate at year 1 was 61%. Survival was significantly higher in patients submitted later to combination therapy compared to chemotherapy, surgery or symptomatic treatment (p < 0.001). Fluoroscopy was used in 57% of the procedures. Clinical success was 79%. A second SEMS was needed during the procedure in 6% of the patients. Rate of early and late complications was 11% and 5%, respectively. Fluoroscopy guidance did not influence the occurrence of immediate (p = 0.385), early (p = 0.950) or late complications (p = 0.057). Thirty-three percent of patients underwent surgery at a later stage, with neo-adjuvant therapy in 18%.

CONCLUSIONS

SEMS provide a relative safe and successful treatment in a palliative or bridge-to-surgery indication. No significant differences were found in SEMS placement success, early complications or late complications considering fluoroscopy guidance.