Endoscopic ultrasound-guided through-the-needle microforceps biopsy in the evaluation of pancreatic cystic lesions: a multicenter study

Value of EUS-guided through-the-needle biopsy in the diagnosis of pancreatic cystic neoplasms: An 8-year experience

Background and Objectives

An accurate diagnosis is crucial for the clinical management of pancreatic cystic neoplasm (PCN). EUS-guided through-the-needle biopsy (EUS-TTNB) is a novel technique for improving the accuracy of PCN diagnosis. There is insufficient evidence about the efficacy of EUS-TTNB. This study aims to evaluate the feasibility and diagnostic performance of EUS-TTNB for PCN.

Methods

Between June 2015 and July 2023, we prospectively enrolled 454 patients with a clinical concern for PCN in our database. After excluding those diagnosed with pancreatic cancer, pseudocysts, or other no-neoplasms, we assessed 326 patients with 329 cysts undergoing EUS-guided fine-needle-aspiration (EUS-FNA) or EUS-TTNB for evaluation. The primary indicators were tissue acquisition yield and diagnostic yield. The cyst characteristics (size, location, the presence of septation, mural nodule, and solid mass) and the number of biopsy samples were chosen for the analysis of factors associated with diagnostic performance.

Results

There were 220 (67.5%) females and 106 (32.5%) males, and the median patient age was 50 years (range, 18-88). There were 329 cysts sampled by FNA and 143 by TTNB. The median cyst size was 31.5 mm (range, 6.9-114.0). The diagnostic yields of FNA and TTNB were 35.7% (112/314) and 57.5% (73/127), respectively (P < 0.001). Special cyst types were diagnosed by TTNB in 58 (45.7%, 58/127) cysts, 19 of which had surgical pathology. Fifteen of 19 TTNB diagnoses were concordant with the surgical pathology.

Conclusion

EUS-TTNB is an option to improve the diagnosis of PCN. Standardized procedures and appropriate indications for TTNB need to be studied.

Endoscopic Ultrasound-Guided Through-the-Needle Biopsy: A Narrative Review of the Technique and Its Emerging Role in Pancreatic Cyst Diagnosis

Pancreatic cystic lesions (PCLs) pose a diagnostic challenge due to their increasing incidence and the limitations of cross-sectional imaging and endoscopic-ultrasound-guided fine-needle aspiration (EUS-FNA). EUS-guided through the needle biopsy (EUS-TTNB) has emerged as a promising tool for improving the accuracy of cyst type determination and neoplastic risk stratification. EUS-TTNB demonstrates superior diagnostic performance over EUS-FNA, providing critical preoperative information that can significantly influence patient management and reduce unnecessary surgeries. However, the procedure has risks, with an overall adverse event rate of approximately 9%. Preventive measures and further prospective studies are essential to optimize its safety and efficacy. This review highlights the potential of EUS-TTNB to enhance the diagnostic and management approaches for patients with PCLs. It examines the current state of EUS-TTNB, including available devices, indications, procedural techniques, specimen handling, diagnostic yield, clinical impact, and associated adverse events.

Value of Endoscopic Ultrasound-Guided Through-the-Needle Biopsy in Pancreatic Cystic Lesions. A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

Endoscopic ultrasound-guided through-the-needle biopsy (EUS-TTNB) has been used over the past few years to increase diagnostic accuracy for pancreatic cystic lesions (PCLs). However, many concerns remain regarding its widespread use. This systematic review and meta-analysis aimed to pool the data from high-quality studies to evaluate the utility of EUS-TTNB in diagnosing PCLs.

METHODS

Electronic databases (PubMed, Embase, and Cochrane Library) from January 2010 through October 2022 were searched for publications addressing the diagnostic performance of EUS-TTNB in the diagnosis of pancreatic cystic lesions. Pooled proportions were calculated using fixed (inverse variance) and random-effects (DerSimonian-Laird) models.

RESULTS

The initial search identified 635 studies, of which 35 relevant articles were reviewed. We extracted data from 11 studies that met the inclusion criterion, comprising a total of 575 patients. Mean patient age was 62.25 years ± 6.12 with females constituting 61.39% of the study population. Pooled sensitivity of EUS-TTNB in differentiating a PCL as neoplastic or non-neoplastic was 76.60% (95% CI = 72.60-80. 30). For the same indication, EUS TTNB had a pooled specificity of 98.90% (95% CI = 93.80-100.00). The positive likelihood ratio was 10.28 (95% CI = 4.77-22.15), and the negative likelihood ratio was 0.26 (95% CI = 0.22-0.31). The pooled diagnostic odds ratio for EUS-TTNB in diagnosing PCLs as malignant/pre-malignant vs. non-malignant was 41.34 (95% CI = 17.42-98.08). Pooled adverse event rates were 3.04% (95% CI = 1.83-4.54) for pancreatitis, 4.02% (95% CI = 2.61-5.72) for intra-cystic bleeding, 0.94% (95% CI = 0.33-1.86) for fever, and 1.73% (95% CI = 0.85-2.91) for other minor events.

CONCLUSIONS

EUS-TTNB has good sensitivity with excellent specificity in accurately classifying PCLs as neoplastic or non-neoplastic. Adding EUS-TTNB to EUS-FNA increases the accuracy of EUS-guided approach in diagnosing PCLs. However, it could significantly increase the risk of post-procedural pancreatitis.

Rare Pancreatic/Peripancreatic Cystic Lesions Can Be Accurately Characterized by EUS with Through-the-Needle Biopsy-A Unique Pictorial Essay with Clinical and Histopathological Correlations

Due to their aspecific macroscopic appearance, uncommon pancreatic cystic lesions (PCLs) are often misdiagnosed as mucinous lesions and improperly resected. We aimed to evaluate the endoscopic ultrasound (EUS)-guided through-the-needle biopsy (TTNB) capacity of the preoperative diagnosis of uncommon PCLs. Overall, 136 patients with PCLs who underwent EUS-TTNB between 2016 and 2022 were retrospectively identified. Common histotypes (e.g., IPMN, serous cystadenoma, and mucinous cystadenoma) were excluded and 26 (19.1%) patients (15 female, mean age 52.9 ± 10.4) were analyzed. The EUS findings, adverse events (AEs), and TTNB outcomes in uncommon PCLs were evaluated. The cysts histotype was accurately diagnosed by TTNB in 24/26 (92.3%) cases (seven cystic neuroendocrine tumors, four squamoid cysts, three acinar cells cystadenomas, two lymphoepithelial cysts, two mucinous non-neoplastic cysts, two bronchogenic cysts, two cystic lymphangiomas, one solid-pseudopapillary neoplasm, and one schwannoma). In the remaining two cases, lymphangioma was eventually diagnosed after resection. Surgery was performed in 15/26 (57.7%) patients. The mean follow-up of non-surgical patients was 32.5 months. One severe acute case of pancreatitis (3.8%) that required surgery occurred after EUS-TTNB. Uncommon pancreatic/peripancreatic lesions represent the 19.1% of PCLs in our series, with mainly benign histotypes. TTNB demonstrated a high diagnostic performance with a low rate of AEs in this setting, representing a reliable tool with which to avoid useless surgery.

Endoscopic Imaging of Pancreatic Cysts

Pancreatic cystic lesions (PCLs) have been diagnosed with increasing frequency likely due to the widespread use of cross-sectional imaging. A precise diagnosis of the PCL is important because it helps identify patients in need of surgical resection and those who can undergo surveillance imaging. A combination of clinical and imaging findings as well as cyst fluid markers can help classify PCLs and guide management. This review focuses on endoscopic imaging of PCLs including endoscopic and endosonographic features and fine needle aspiration. We then review the role of adjunct techniques, such as microforceps, contrast-enhanced endoscopic ultrasound, pancreatoscopy, and confocal laser endomicroscopy.

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.

Comparative Performance of Endoscopic Ultrasound-Based Techniques in Patients With Pancreatic Cystic Lesions: A Network Meta-Analysis

INTRODUCTION

Evidence on the comparative diagnostic performance of endoscopic ultrasound (EUS)-based techniques for pancreatic cystic lesions (PCLs) is limited. This network meta-analysis comprehensively compared EUS-based techniques for PCL diagnosis.

METHODS

A comprehensive literature search was performed for all comparative studies assessing the accuracy of 2 or more modalities for PCL diagnosis. The primary outcome was the diagnostic efficacy for mucinous PCLs. Secondary outcomes were the diagnostic efficacy for malignant PCLs, diagnostic success rate, and adverse event rate. A network meta-analysis was conducted using the ANOVA model to assess the diagnostic accuracy of each index.

RESULTS

Forty studies comprising 3,641 patients were identified. The network ranking of the superiority index for EUS-guided needle-based confocal laser endomicroscopy (EUS-nCLE) and EUS-guided through-the-needle biopsy (EUS-TTNB) were significantly higher than other techniques for differentiating mucinous PCLs; besides, EUS-TTNB was also the optimal technique in identifying malignant PCLs. The evidence was inadequate for EUS-nCLE diagnosing malignant PCLs and contrast-enhanced harmonic EUS diagnosing both mucinous and malignant PCLs. Glucose showed a high sensitivity but low specificity, and molecular analysis (KRAS, GNAS, and KRAS + GNAS mutations) showed a high specificity but low sensitivity for diagnosing mucinous PCLs. Satisfactory results were not obtained during the evaluation of the efficiency of pancreatic cyst fluid (PCF) biomarkers in detecting malignant PCLs.

DISCUSSION

For centers with relevant expertise and facilities, EUS-TTNB and EUS-nCLE were better choices for the diagnosis of PCLs. Further studies are urgently required for further improving PCF biomarkers and validating the diagnostic performance of the index techniques.

Role of Endoscopy in Management of Upper Gastrointestinal Cancers

Upper gastrointestinal (GI) malignancy is a leading cause of cancer-related morbidity and mortality. Upper endoscopy has an established role in diagnosing and staging upper GI cancers, screening for pre-malignant lesions, and providing palliation in cases of advanced malignancy. New advances in endoscopic techniques and technology have improved diagnostic accuracy and increased the therapeutic potential of upper endoscopy. We aim to describe the different types of endoscopic technology used in cancer diagnosis, summarize the current guidelines for endoscopic diagnosis and treatment of malignant and pre-malignant lesions, and explore new potential roles for endoscopy in cancer therapy.

State-of-the-Art Update of Pancreatic Cysts

Andrew Canakis.

Confocal Laser Endomicroscopy in the Diagnosis of Biliary and Pancreatic Disorders: A Systematic Analysis

BACKGROUND/AIMS

Endoscopic visualization of the microscopic anatomy can facilitate the real-time diagnosis of pancreatobiliary disorders and provide guidance for treatment. This study aimed to review the technique, image classification, and diagnostic performance of confocal laser endomicroscopy (CLE).

METHODS

We conducted a systematic review of CLE in pancreatic and biliary ducts of humans, and have provided a narrative of the technique, image classification, diagnostic performance, ongoing research, and limitations.

RESULTS

Probe-based CLE differentiates malignant from benign biliary strictures (sensitivity, ≥89%; specificity, ≥61%). Needlebased CLE differentiates mucinous from non-mucinous pancreatic cysts (sensitivity, 59%; specificity, ≥94%) and identifies dysplasia. Pancreatitis may develop in 2-7% of pancreatic cyst cases. Needle-based CLE has potential applications in adenocarcinoma, neuroendocrine tumors, and pancreatitis (chronic or autoimmune). Costs, catheter lifespan, endoscopist training, and interobserver variability are challenges for routine utilization.

CONCLUSION

CLE reveals microscopic pancreatobiliary system anatomy with adequate specificity and sensitivity. Reducing costs and simplifying image interpretation will promote utilization by advanced endoscopists.

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.

Through-the-needle biopsy of pancreatic cystic lesions: current evidence and implications for clinical practice

INTRODUCTION

There is increasing evidence to support the efficacy of endoscopic ultrasound (EUS)-guided through-the-needle biopsy (TTNB) technique as a means of sampling pancreatic cystic lesions (PCLs). Results provide evidence demonstrating the benefits of this procedure over standard EUS fine-needle aspiration (FNA), thus supporting a push for its widespread implementation in clinical practice. Though this technique has demonstrated advantages, achieving these advantages in clinical practice is contingent upon careful considerations to ensure safety and efficacy.

AREAS COVERED

The purpose of this review is to assess the level of evidence supporting the use of through-the-needle biopsy, revise its main technical and procedural characteristics, and to develop suggested guidelines outlining the safe assimilation of this device in clinical practice.

EXPERT OPINION

EUS-TTNB enables more definitive and accurate diagnosis of PCLs by providing higher-quality histological samples. However, EUS-TTNB is not appropriate for all PCLs. Selection of suitable patients as well as morphology and risk factors of the cystic lesion is a crucial component of achieving the described benefits of this procedure while minimizing risks of adverse effects. Subjects with weak or absent indications for this procedure are susceptible to a range of complications and may even result in fatality.

Cystic pancreatic lesions, the endless dilemma

Cystic pancreatic lesions involve a wide variety of pathological entities that include neoplastic and non-neoplastic lesions. The proper diagnosis, differentiation, and staging of these cystic lesions are considered a crucial issue in planning further management. There are great challenges for their diagnostic models. In our time, new emerging methods for this diagnosis have been discovered. Endoscopic ultrasonography-guided fine-needle aspiration cytology with chemical and molecular analysis of cyst fluid and EUS-guided fine needle-based confocal laser endomicroscopy, through the needle microforceps biopsy, and single-operator cholangioscopy/pancreatoscopy are promising methods that have been used in the diagnosis of cystic pancreatic lesions. Hereby we discuss the diagnosis of cystic pancreatic lesions and the benefits of various diagnostic models.

Diagnostic accuracy of EUS-guided through-the-needle-biopsies and simultaneously obtained fine needle aspiration for cytology from pancreatic cysts: A systematic review and meta-analysis

OBJECTIVES

To address the diagnostic accuracy of endoscopic ultrasound guided through-the-needle-biopsies (TTNBs) and simultaneously obtained cytology samples from pancreatic cysts compared to the final histopathological diagnosis of the surgical specimen, and to give an overview of ancillary tests performed on TTNBs.

METHODS

A literature search was conducted in MEDLINE, Embase and Scopus. Studies were included in the meta-analysis, if they had data for TTNB, cytology and a surgical specimen of pancreatic cysts as reference standard. The assessment of the risk of bias and quality of the included studies was conducted using the modified QUADAS-2 tool.

RESULTS

Ten studies with 99 patients were included in the meta-analysis. Data regarding study design and clinicopathological features were extracted systematically. For TTNB, pooled sensitivity was 0.86 (95 % CI 0.62-0.96), specificity 0.95 (95 % CI 0.79-0.99) and area under the curve (AUC) 0.86 for the diagnosis of a mucinous cyst and pooled sensitivity was 0.78 (95 % CI 0.61-0.89), specificity 0.99 (95 % CI 0.90-0.99) and AUC 0.92 for the diagnosis of a high-risk cyst. For a specific diagnosis, pooled sensitivity was 0.69 (95 % CI 0.50-0.83), specificity 0.47 (95 % CI 0.28-0.68) and AUC 0.49. For cytology performed simultaneously, pooled sensitivity was 0.46 (95 % CI 0.35-0.57), specificity 0.90 (95 % CI 0.46-0.99) and AUC 0.64 for the diagnosis of mucinous cysts, and pooled sensitivity was 0.38 (95 % CI 0.23-0.55), specificity 0.99 (95 % CI 0.90-0.99) and AUC 0.84 for the diagnosis of a high-risk cyst. For a specific diagnosis, pooled sensitivity was 0.29 (95 % CI 0.21-0.39), specificity 0.45 (95 % CI 0.25-0.66) and AUC 0.30. Furthermore, immunohistochemical stains can be useful to establish the specific cyst subtype.

CONCLUSIONS

TTNBs have a higher sensitivity and specificity than cytology for the diagnosis of mucinous cyst and high- risk cysts of the pancreas.

Clinical impact of endoscopic ultrasound-guided through-the-needle microbiopsy in patients with pancreatic cysts

BACKGROUND

The limited data on the utility of endoscopic ultrasound (EUS)-guided through-the-needle biopsies (TTNBs) in patients with pancreatic cystic lesions (PCLs) originate mainly from retrospective studies. Our aim was to determine the clinical impact of TTNBs, their added diagnostic value, and the adverse event rate in a prospective setting.

METHODS

This was a prospective, single-center, open-label controlled study. Between February 2018 and August 2019, consecutive patients presenting with a PCL of 15 mm or more and referred for EUS were included. Primary outcome was a change in clinical management of PCLs following TTNB compared with cross-sectional imaging and cytology. Adverse events were defined according to the ASGE lexicon.

RESULTS

101 patients were included. TTNBs led to a change in clinical management in 11.9 % of cases (n = 12). Of these, 10 had serous cysts and surveillance was discontinued, while one of the remaining two cases underwent surgery following diagnosis of a mucinous cystic neoplasm. The diagnostic yield of TTNBs for a specific cyst diagnosis was higher compared with FNA cytology (69.3 % vs. 20.8 %, respectively; P < 0.001). The adverse event rate was 9.9 % (n = 10; 95 % confidence interval 5.4 % - 17.3 %), with the most common event being acute pancreatitis (n = 9). Four of the observed adverse events were severe, including one fatal outcome.

CONCLUSIONS

TTNBs resulted in a change of clinical management in about one in every 10 patients; however, the associated adverse event risk was substantial. Further studies are warranted to elucidate in which subgroups of patients the clinical benefit outweighs the risks.

EUS-through-the-needle microbiopsy forceps in pancreatic cystic lesions: A systematic review

Pancreatic cystic lesions (PCLs) are being increasingly encountered in clinical practice, and sometimes, they can represent a diagnostic challenge. Recently, a through-the-needle micro forceps biopsy (MFB) device was introduced in the endosonography practice to facilitate EUS-guided sampling of PCLs. The aim was to perform a systematic review of studies evaluating the technical aspects, safety, and efficacy of the EUS-guided MFB for PCLs. A literature search was performed in three major databases, PubMed, Embase, and Web of Science in September 2019 using the search terms: "through-the-needle," "biopsy forceps," "microforceps," "endoscopic ultrasound," and "endosonography." Case reports and case series with <10 patients were excluded from the analysis. Altogether nine studies reporting on 463 patients were included in our systematic review. The mean age of the patients was 68.3 years, with a slight female predominance (60.9%). Most of the cysts were located in the body/tail of the pancreas (61.2%), with an overall mean size of 33 mm. The technical success of EUS-guided MFB was reported in 98.5%. The tissue acquisition yield reported was 88.2%, and the diagnostic accuracy was 68.6%. Adverse events were reported in 9.7%. EUS-guided MFB is technically feasible, safe, and has a high diagnostic accuracy for PCLs.

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.

Diagnostic performance of endoscopic ultrasound through-the-needle microforceps biopsy of pancreatic cystic lesions: Systematic review with meta-analysis

OBJECTIVES

Endoscopic ultrasound through-the-needle biopsy (EUS-TTNB) is a useful tool for differential diagnosis among pancreatic cystic lesions (PCLs). Cystic fluid cytology (CFC) is recommended by guidelines, but its diagnostic accuracy is about 50%. The aim of this meta-analysis is to assess the clinical impact of EUS-TTNB in terms of technical success (TS), histological accuracy (HA) and diagnostic yield (DY).

METHODS

Original studies in English language on EUS-TTNB were searched in MEDLINE and EMBASE until October 2019. Diagnostic accuracy of EUS-TTNB for identification of mucinous PCLs was calculated using individual diagnostic data of patients who underwent CFC and surgery.

RESULTS

Nine studies, including 454 patients who underwent EUS-TTNB, met the inclusion criteria for the meta-analysis. TS and HA of EUS-TTNB were, respectively, 98.5% (95% Confidence Interval [CI] 97.3%-99.6%) and 86.7% (95%CI 80.1-93.4). DY was 69.5% (95%CI 59.2-79.7) for EUS-TTNB and 28.7% (95%CI 15.7-41.6) for CFC. Heterogeneity persisted significantly high in most of subgroup analyses. In the multivariate meta-regression, cyst size was independently associated with higher DY. Sensitivity and specificity for mucinous PCLs were 88.6 and 94.7% for EUS-TTNB, and 40 and 100% for CFC. Adverse events rate was 8.6% (95%CI 4.0-13.1).

CONCLUSIONS

This meta-analysis shows that EUS-TTNB is a feasible technique that allows a high rate of adequate specimens to be obtained for histology; in about two-thirds of patients a specific histotype diagnosis could be assessed. The number of adverse events is slightly higher respect to standard EUS-FNA, but complications are very rarely severe.

Endoscopic ultrasound-guided through-the-needle microforceps biopsy improves diagnostic yield for pancreatic cystic lesions: a systematic review and meta-analysis

Background and study aims  Given variable diagnostic yield of endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) for pancreatic cystic lesions (PCLs), a through-the-needle (TTN) microforceps biopsy device passed through a 19-gauge FNA needle has been devised to improve tissue sampling. This was a systematic review and meta-analysis to evaluate the feasibility, diagnostic yield, and safety of EUS-guided TTN microforceps biopsy for diagnosis of PCLs. Methods  Individualized searches were developed in accordance with PRISMA and MOOSE guidelines. This was a cumulative meta-analysis performed by calculating pooled proportions with rates estimated using random effects models. Measured outcomes included pooled technical success, diagnostic yield, accuracy, and procedure-associated adverse events (AEs) as well as comparison to conventional FNA. Results  Eleven studies (n = 518 patients; mean age 64.13 ± 5.83 years; 58.19 % female) were included. Mean PCL size was 33.39 ± 3.72 mm with the pancreatic head/uncinate (35.50 %) being the most common location. A mean of 2.47 ± 0.92 forceps passes were performed with a mean of 2.79 ± 0.81 microbiopsies obtained per lesion. Pooled technical success was 97.12 % (95 % CI, 93.73-98.71; I ²  = 34.49) with a diagnostic yield of 79.60 % (95 % CI, 72.62-85.16; I ²  = 56.00), and accuracy of 82.76 % [(95 % CI, 77.80-86.80; I ²  = 0.00). The pooled serious adverse event rate was 1.08 % (95 % CI, 0.43-2.69; I ²  = 0.00). Compared to conventional FNA, TTN microforceps biopsy resulted in significant improvement in diagnostic yield [OR 4.79 (95 % CI: 1.52-15.06; P  = 0.007)] and diagnostic accuracy [OR 8.69 (95 % CI, 1.12-67.12; P  = 0.038)], respectively. Conclusions  EUS-guided TTN microforceps biopsy appears to be safe and effective for diagnosis of PCLs with improvement in diagnostic yield and accuracy when compared to FNA alone.

Endoscopic ultrasound-guided, through-the-needle forceps biopsy for diagnosis of pancreatic cystic lesions: a systematic review

Background and study aims  Pancreatic cystic lesions (PCL), are a heterogeneous group of cystic lesions. Some patients with PCLs have a significantly higher overall risk of pancreatic cancer and the only test that can differentiate benign and malignnat PCL is fine-needle aspiration plus cytological analysis, but its sensitivity is very low. Through-the-needle direct intracystic biopsy is a technique that allows acquisition of targeted tissue from PCLs and it may improve the diagnostic yield for them. The aim of this study was to review articles about endoscopic ultrasound (EUS)-guided through-the-needle intracystic biopsy for targeted tissue acquisition and diagnosis of PCLs. Methods  A systematic review of computerized bibliographic databases was carried out for studies of EUS-guided through-the-needle forceps biopsy (EUS-TTNB) of PCLs. The percentages and their 95 % confidence intervals (CIs) were calculated for all the considered endpoints (technical success, adequate specimens, adverse events (AEs), and overall diagnosis). Results  Overall, eight studies with a total of 423 patients were identified. Pooled technical success was 95.6 % of the cases (399/423), (95 % CI, 93.2 %-97.3 %). Technical failure rate was 5.1 % (24 cases). Frequency of adequate specimens was 82.2 %, (95 % CI, 78.5 %-85.8 %). Adverse events were reported in seven of the eight studies. Forty-two total adverse events were reported (10.1 %) (95 % CI, 7.3 %-13.6 %). The overall ability to provide a specific diagnosis with EUS-TTNB for diagnosis of pancreatic cystic lesions was 74.6 % (313 cases), (95 % CI: 70.2 %-78.7 %). The most frequent diagnoses found with EUS-TTNB were mucinous cystic neoplasms (MCN) in 96 cases (30.6 %), IPMN in 80 cases (25.5 %), and serous cystoadenoma neoplasm (SCN) in 48 cases (15.3 %). Conclusions  Through-the-needle forceps biopsy appears to be effective and safe, with few AE for diagnosis of pancreatic cystic lesions. This technique had acceptable rates of technical and clinical success and an excellent safety profile. TTNB is associated with a high tissue acquisition yield and provided additional diagnostic yield for mucinous pancreatic lesions. TTNB may be a useful adjunctive tool for EUS-guided assessment 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.

Endoscopic Ultrasound-Guided Management of Chronic Pancreatitis

PURPOSE OF REVIEW

The purpose of this review is to discuss the role of endoscopic ultrasound (EUS) in the diagnosis and treatment of chronic pancreatitis (CP).

RECENT FINDINGS

EUS has evolved and become invaluable in diagnosing early CP with the use of elastography and contrast enhancement. Lumen-apposing metal stents have allowed for easier transmural drainage and necrosectomy for pancreatic pseudocyst and walled of necrosis. EUS-guided pancreatic duct drainage is being utilized for pancreatic duct complications including stenosis, stones, and duct disruptions that are not amendable to endoscopic retrograde cholangiopancreatography. EUS is an effective tool that assists with the diagnosis and treatment of CP. The technology continues to evolve allowing for diagnosis of CP in earlier stages, which enables more effective therapy. The development of new EUS-guided tools and techniques has improved the treatment of complications from CP.

Diagnostic yield of EUS-guided through-the-needle microforceps biopsy versus EUS-FNA of pancreatic cystic lesions: a systematic review and meta-analysis

Background and study aims  Accurate diagnosis and risk stratification of pancreatic cysts (PCs) is challenging. The aim of this study was to perform a systematic review and meta-analysis to assess the feasibility, safety, and diagnostic yield of endoscopic ultrasound-guided through-the-needle biopsy (TTNB) versus fine-needle aspiration (FNA) in PCs. Methods  Comprehensive search of databases (PubMed, EMBASE, Cochrane, Web of Science) for relevant studies on TTNB of PCs (from inception to June 2019). The primary outcome was to compare the pooled diagnostic yield and concordance rate with surgical pathology of TTNB histology and FNA cytology of PCs. The secondary outcome was to estimate the safety profile of TTNB. Results: Eight studies (426 patients) were included. The diagnostic yield was significantly higher with TTNB over FNA for a specific cyst type (OR: 9.4; 95 % CI: [5.7-15.4]; I ²  = 48) or a mucinous cyst (MC) (OR: 3.9; 95 % CI: [2.0-7.4], I ²  = 72 %). The concordance rate with surgical pathology was significantly higher with TTNB over FNA for a specific cyst type (OR: 13.5; 95 % CI: [3.5-52.3]; I ²  = 48), for a MC (OR: 8.9; 95 % [CI: 1.9-40.8]; I ²  = 29), and for MC histologic severity (OR: 10.4; 95 % CI: [2.9-36.9]; I ²  = 0). The pooled sensitivity and specificity of TTNB for MCs were 90.1 % (95 % CI: [78.4-97.6]; I ²  = 36.5 %) and 94 % (95 % CI: [81.5-99.7]; I ²  = 0), respectively. The pooled adverse event rate was 7.0 % (95 % CI: [2.3-14.1]; I ²  = 82.9). Conclusions  TTNB is safe, has a high sensitivity and specificity for MCs and may be superior to FNA cytology in risk-stratifying MCs and providing a specific cyst diagnosis.

Impact of EUS-guided microforceps biopsy sampling and needle-based confocal laser endomicroscopy on the diagnostic yield and clinical management of pancreatic cystic lesions

BACKGROUND AND AIMS

EUS-guided microforceps biopsy sampling (MFB) and needle-based confocal laser endomicroscopy (nCLE) are emerging diagnostic tools for pancreatic cystic lesions (PCLs). There is a paucity of data regarding their performance and impact. The aim of this study was to compare diagnostic outcomes and changes in clinical management resulting from MFB and nCLE use in PCLs.

METHODS

This was a single-center retrospective study of patients with PCLs who underwent combined EUS-guided FNA, MFB, and nCLE. Primary outcomes included diagnostic yield (specific PCL type) and change in clinical management for each modality compared with the current "composite standard" (CS) obtained by combining clinical, morphologic, cyst fluid cytology, and chemical analysis.

RESULTS

Forty-four cysts were studied in 44 patients. Technical success was 100% for EUS-FNA, 88.6% for MFB, and 97.7% for nCLE. Of 44 procedures, there was 1 adverse event (2.3%, an infected pseudocyst). Diagnostic yield for each individual modality was 34.1% for CS, 75.0% for MFB (P < .05 vs CS), and 84.1% for nCLE (P < .05 vs CS). Diagnostic yield for combined tests was 79.5% for CS/MFB, 88.6% for CS/nCLE, and 93.2% for CS/MFB/nCLE (P = not significant). Compared with the CS, the use of MFB, nCLE, and their combination led to overall change in clinical management in 38.6%, 43.2%, and 52.3% of cases, respectively. MFB and nCLE led to an overall increase in discontinuation of surveillance (MFB, 34.1% [P < .05]; nCLE, 31.8% [P < .05]), led by a reduction in the indication for follow-up radiologic or endoscopic studies (MFB, 34.1% [P < .05]; nCLE, 38.6% [P < .05]). Based on MFB and nCLE, 2 of 28 (7.1%) and 3 of 28 (10.7%) patients who would have undergone further surveillance were referred for surgery.

CONCLUSIONS

In the evaluation of PCLs, the use of combined EUS-guided FNA, MFB, and nCLE is safe. MFB and nCLE led to significant improvements in specific PCL diagnosis, which in turn has major impacts in clinical management.

EUS-guided through-the-needle microbiopsy of pancreatic cysts: Technical aspects (with video)

Pancreatic cystic lesions are frequently encountered and diagnostically challenging as some of the cysts may have malignant potential (mucinous) while others are completely benign (serous). EUS-guided through-the-needle biopsy (EUS-TTNB) of the cyst wall has recently been introduced as an alternative to cyst fluid cytology. Several studies have shown that microbiopsies outperform cytology in terms of distinction between mucinous and nonmucinous lesions, but also in determining the specific cyst diagnosis. However, little is known about the technical aspects of tissue sampling with TTNB. Herein, we summarize our experience with the procedure in a tertiary referral center and discuss indications, technical aspects, and safety of the procedure. Most adverse events (AEs) associated with the procedure are mild, but there is emerging evidence that the rate of postprocedural pancreatitis is higher compared to standard fine-needle aspiration. The added diagnostic yield should therefore be placed in perspective with an increased risk of AEs. Prospective studies are warranted to fully identify which patient groups could benefit from EUS-TTNB.

Utility of endoscopic ultrasound and endoscopic ultrasound-guided fine-needle aspiration for the diagnosis and management of pancreatic cystic lesions: Differences between the guidelines

Recent advances and frequent use of cross-sectional imaging studies have increased opportunities for incidental diagnoses of pancreatic cystic lesions (PCL). In the management of PCL, distinguishing between mucinous versus non-mucinous and malignant versus benign cysts is important to diagnose pancreatic cancer in its early stage. For this reason, there have been several guidelines to manage PCL. Endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (FNA) play important roles in the guidelines, although there are some differences in their roles. In this review, we aimed to evaluate the current status of EUS and EUS-FNA in the management of PCL and the status of these procedures in the guidelines.

Association between macroscopically visible tissue samples and diagnostic accuracy of EUS-guided through-the-needle microforceps biopsy sampling of pancreatic cystic lesions

BACKGROUND AND AIMS

EUS-guided through-the-needle biopsy (TTNB) sampling has been reported to improve diagnostic yield compared with cytology for the evaluation of pancreatic cystic lesions (PCLs). The number of macroscopically visible tissue samples needed to reach an adequate diagnosis is still unknown.

METHODS

This is a retrospective, single-center study on consecutive patients with PCLs with risk features (cyst >3 cm, thickened wall, cyst growth during follow-up, and mural nodules) who underwent TTNB sampling. The capability of differentiating mucinous versus nonmucinous cysts, ability to obtain a cyst-lining epithelium, definition of the grade of dysplasia, and specific diagnosis of cyst histotype were evaluated for 1, 2, or 3 TTNB macroscopically visible specimens.

RESULTS

Sixty-one patients were evaluated. A 100% histologic adequacy was reached by 2 samples (P = .05 versus 1). Compared with cytology, 1 TTNB specimen improved the possibility of defining cyst histotype (P < .0001), whereas 2 specimens increased all 4 diagnostic categories (P < .003). Two specimens also increased diagnostic yield compared with 1 sample (P < .085). The collection of a third sample did not improve the value of any diagnostic categories. A specific diagnosis was reached in 74% of patients with 2 histologic samples. The diagnostic reliability of TTNB sampling compared with surgical histology was 90%, with a 22.9% rate of adverse events.

CONCLUSIONS

Two TTNB macroscopically visible specimens reached 100% histologic adequacy and a specific diagnosis in 74% of patients. The collection of a third specimen did not add any additional information and should be avoided to possibly decrease the risk of adverse events.

Endoscopic ultrasound-through-the-needle biopsy in pancreatic cystic lesions: A large single center experience

BACKGROUND

Establishing a diagnosis of pancreatic cystic lesions (PCLs) preoperatively still remains challenging. Recently, endoscopic ultrasound (EUS)-through-the-needle biopsy (EUS-TTNB) using microforceps in PCLs has been made available.

AIM

To assess the efficacy and safety of EUS-TTNB in the diagnosis of PCLs.

METHODS

We retrospectively collected data of patients with PCLs who underwent both EUS-fine-needle aspiration (FNA) for cytology and EUS-TTNB at our institution since 2016. EUS-FNA for cytology was followed by EUS-TTNB in the same session. Evaluation of the cyst location, primary diagnosis, adverse events, and comparison between the cytologic fluid analyses and histopathology was performed. Technical success of EUS-TTNB was defined as visible tissue present after biopsy. Clinical success was defined as the presence of a specimen adequate to make a histologic or cytologic diagnosis.

RESULTS

A total of 56 patients (mean age 66.9 ± 11.7, 53.6% females) with PCLs were enrolled over the study period. The mean cyst size was 28.8 mm (12-85 mm). The EUS-TTNB procedure was technically successful in all patients (100%). The clinical success rate using EUS-TTNB was much higher than standard EUS-FNA, respectively 80.4% (45/56) vs 25% (14/56). Adverse events occurred in 2 patients (3.6%) who developed mild pancreatitis that resolved with medical therapy. Using TTNB specimens, 23 of 32 cases (71.9%) with intraductal papillary mucinous neoplasm were further differentiated into gastric type (19 patients) and pancreaticobiliary type (4 patients) based on immunochemical staining.

CONCLUSION

EUS-TTNB for PCLs was technically feasible and had a favorable safety profile. Furthermore, the diagnostic yield for PCLs was much higher with EUS-TTNB than standard EUS-FNA cytology and fluid carcinoembryonic antigen. EUS-TTNB should be considered as an adjunct to EUS-FNA and cytologic analysis in the diagnosis and management of PCLs.

Interobserver agreement among expert pathologists on through-the-needle microforceps biopsy samples for evaluation of pancreatic cystic lesions

BACKGROUND AND AIMS

The recent development of microforceps for EUS through-the-needle biopsy (TTNB) sampling of the wall of pancreatic cystic lesions (PCLs) allows the collection of histologic specimens never handled and evaluated before by pathologists. We aimed to estimate the interobserver agreement among pathologists in evaluating such samples.

METHODS

TTNB specimen slides from 40 PCLs with worrisome features were retrieved and independently evaluated for specimen adequacy, presence of lining epithelium, grade of epithelial dysplasia, presence of ovarian type stroma, and specific diagnosis by 6 expert pathologists from 6 different tertiary care centers. The Gwet's AC1 was used to assess interobserver agreement.

RESULTS

An almost perfect agreement was observed for specimen adequacy (AC1, .82; 95% confidence interval [CI], .79-.98), presence of lesional epithelium (AC1, .90; 95% CI, .86-.92), epithelial dysplasia (AC1, .97; 95% CI, .95-.99), and ovarian-like stroma (AC1, .90; 95% CI, .86-.93). When considering all diagnoses separately, a moderate to substantial agreement was observed (AC1, .62; 95% CI, .57-.67), similarly to mucinous cysts versus serous adenoma versus other diagnoses (AC1, .65; 95% CI, .59-.70) and for mucinous cysts versus all other diagnoses (AC1,.74; 95% CI, .68-.84). The agreement for diagnosis of mucinous cystic neoplasm versus intraductal mucinous papillary neoplasm was almost perfect (AC1, .88; 95% CI, .81-.95).

CONCLUSIONS

Interobserver agreement between expert pathologists in the evaluation of TTNB samples from PCLs with worrisome features was close to perfection for all evaluated parameters, except definitive diagnosis. When mucinous cystic lesions were compared versus all other diagnoses, the agreement became substantial, thus indicating that TTNB specimens can provide important information for PCL management decisions.

Therapeutic EUS: New tools, new devices, new applications

Linear echoendoscopes with large instrument channels enable EUS-guided interventions in organs and anatomical spaces in proximity to the gastrointestinal tract. Novel devices and tools designed for EUS-guided transluminal interventions allow various new applications and improve the efficacy and safety of these procedures. New-generation biopsy needles provide higher histology rates and require less passes. Specially designed stents and stent insertion devices enable intra- and extra-hepatic bile and pancreatic duct stenting as well as gallbladder drainage. Currently, EUS-guided biliary drainage in obstructive jaundice due to malignant distal bile duct obstruction is feasible and safe when ERCP has failed. It might replace ERCP as first choice intervention in future. EUS-guided transmural stenting is regarded as the preferred intervention in the management of symptomatic peripancreatic fluid collections. Creating a new anastomosis between different organs such as gastrojejunostomy has also become possible with lumen-apposing stents. EUS-guided creation of a gastrogastrostomy is a promising novel technique to access the excluded stomach to facilitate conventional ERCP in patients with Roux-en-Y gastric bypass anatomy. The role of EUS in tumor ablation and targeted angiotherapy is also constantly expanding. In this review, we report on the newest developments of therapeutic EUS within the past 4 years.

Histologic Analysis of Endoscopic Ultrasound-Guided Through the Needle Microforceps Biopsies Accurately Identifies Mucinous Pancreas Cysts

BACKGROUND & AIMS

It is a challenge to accurately assess pancreatic cystic lesions (PCLs) and determine their risk. We compared the yield of tissue acquired with endoscopic ultrasound (EUS)-guided microforceps (through the needle tissue biopsy [TTNB]) with that of samples collected by EUS-guided fine-needle-aspiration (EUS-FNA), and the accuracy of analyses of each sample type in the diagnosis of mucinous PCLs.

METHODS

We performed a prospective open-label study of 114 consecutive adults (56.1% women; mean age, 64.2 y) undergoing EUS-FNA evaluation of PCLs (mean size, 35 mm) at 7 centers, from June 20, 2016, through August 31, 2018. Samples were collected from each cyst by FNA and microforceps; samples collected by FNA were analyzed by cytology and samples collected by TTNB were analyzed by histology. Acquisition yield was defined as the percentage of specimens collected that were adequate for cytologic or histologic analysis. Diagnoses of mucinous cysts were made based on identification of pancreatic mucinous epithelium by cytology analysis of FNA samples or histologic analysis of TTNB samples. Surgical specimens were used as the reference standard when available.

RESULTS

The EUS-guided microforceps were successfully inserted into 97.4% (111 of 114) of PCLs. Tissue acquisition yield was significantly higher with TTNB (95 of 114; 83.3%) than FNA (43 of 114; 37.7%) (P < .001). Sixty-one PCLs were determined to be mucinous based on TTNB analysis (53.5%) vs 11 with FNA analysis (9.6%) (P < .001). Among PCLs categorized as equivocal, based on the level of carcinoembryonic antigen, TTNB analysis found 50% (41 of 82) to be mucinous and FNA analysis found 8.5% (7 of 82) to be mucinous (P < .001). Findings from analyses of samples collected by TTNB were 100% concordant with findings from histologic analysis of surgical specimens (14 of 14), whereas only 3 of 14 findings from analysis of samples collected by FNA were in agreement with findings from surgical specimens (21.4%) (P < .001). Four of 5 mucinous PCLs with advanced neoplasia (80%) were detected with TTNB compared with none with FNA (P = .04). Self-limited intracystic bleeding occurred in 7 patients (6.1%), and acute pancreatitis in 6 patients (5.3%).

CONCLUSIONS

In a multicenter prospective study of patients undergoing EUS-FNA for evaluation of PCLs, we found TTNB collection of tissues for histologic analysis to be safe and feasible, with an acquisition yield of 83.3%. Histologic analysis of samples collected by TTNB identified a larger proportion of mucinous PCLs compared with cytologic analysis of samples collected by FNA-even among samples categorized as equivocal, based on the level of carcinoembryonic antigen. More samples collected by TTNB than FNA were found to have advanced neoplasia. Clinicaltrials.gov no: NCT02979509.