Technical feasibility, diagnostic yield, and safety of microforceps biopsies during EUS evaluation of pancreatic cystic lesions (with video)

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.

State-of-the-Art Update of Pancreatic Cysts

Andrew Canakis.

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.

Fine-needle aspiration of pancreatic cystic lesions: a randomized study with long-term follow-up comparing standard and flexible needles

BACKGROUND

Pancreatic cystic lesions (PCLs) are increasingly found on cross-sectional imaging, with the majority having a low risk for malignancy. The added value of fine-needle aspiration (FNA) in risk stratification remains unclear. We evaluated the impact of three FNA needles on diagnostic accuracy, clinical management, and the ability to accrue fluid for tumor markers.

METHODS

A multicenter prospective trial randomized 250 patients with PCLs ≥ 13 mm 2:1:1 to 19G Flex, 19G, and 22G needles with crossover for repeated FNA procedures. Diagnostic accuracy was established at 2-year follow-up, with the final diagnosis from surgical histopathology or consensus diagnosis by experts based sequentially on clinical presentation, imaging, and aspirate analysis in blinded review.

RESULTS

Enrolled patients (36 % symptomatic) had PCLs in the head (44 %), body (28 %), and tail (26 %). Percentage of cyst volume aspirated was 78 % (72 % - 84 %) for 19G Flex, 74 % (64 % - 84 %) for 22G, and 73 % (63 % - 83 %) for 19G (P = 0.84). Successful FNA was significantly higher for 19G Flex (89 % [82 % - 94 %]) and 22G (82 % [70 % - 90 %]) compared with 19G (75 % [63 % - 85 %]) (P = 0.02). Repeated FNA was required more frequently in head/uncinate lesions than in body and tail (P < 0.01). Diagnostic accuracy of the cyst aspirate was 84 % (73 % - 91 %) against histopathology at 2-year follow-up (n = 79), and 77 % (70 % - 83 %) against consensus diagnosis among nonsurgical cases (n = 171). Related serious adverse events occurred in 1.2 % (0.2 % - 3.5 %) of patients.

CONCLUSIONS

Our study results demonstrate a statistically significant difference among the three needles in the overall success rate for aspiration, but not in the percentage of cyst volume aspirated. Flexible needles may be particularly valuable in sampling cystic PCLs in the pancreatic head/uncinate process.

Pancreatic cyst fluid glucose in differentiating mucinous from nonmucinous pancreatic cysts: a systematic review and meta-analysis

BACKGROUND AND AIMS

Recently, low levels of intracystic glucose acquired with EUS-guided pancreatic cyst fluid sampling have been shown to help to differentiate mucinous from nonmucinous cystic neoplasms. The aim of this study was to perform a systematic review and meta-analysis to evaluate the diagnostic characteristics of pancreatic cyst fluid glucose compared with carcinoembryonic antigen (CEA) for pancreatic cystic lesions.

METHODS

Individualized searches were developed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines and meta-analysis analyzed according to Cochrane Diagnostic Test Accuracy working group methodology. A bivariate model was used to compute pooled sensitivity and specificity, likelihood ratio, diagnostic odds ratio, and summary receiver operating characteristics curve for intracystic glucose or CEA alone or combination testing.

RESULTS

Eight studies (609 lesions; mean patient age, 63.56 ± 2.75 years; 60.36% women) were included. The pooled sensitivity for pancreatic cyst fluid glucose was significantly higher compared with CEA alone (91% [95% confidence interval {CI}, 88-94; I² = .00] vs 56% [95% CI, 46-66; I² = 537.14]; P < .001) with no difference in specificity (86% [95% CI, 81-90; I² = 24.16] vs 96% [95% CI, 90-99; I² = 38.06]; P > .05). Diagnostic accuracy was significantly higher for pancreatic cyst fluid glucose versus CEA alone (94% [95% CI, 91-96] vs 85% [95% CI, 82-88]; P < .001). Combination testing with pancreatic cyst fluid glucose and CEA did not improve the diagnostic accuracy compared with glucose alone (97% [95% CI, 95-98] vs 94% [95% CI, 91-96]; P > .05).

CONCLUSIONS

Low pancreatic cyst fluid glucose was associated with a high sensitivity and specificity with significantly improved diagnostic accuracy compared with CEA alone for the diagnosis of mucinous versus nonmucinous pancreatic cystic lesions.

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.

Molecular analysis of EUS-acquired pancreatic cyst fluid for KRAS and GNAS mutations for diagnosis of intraductal papillary mucinous neoplasia and mucinous cystic lesions: a systematic review and meta-analysis

BACKGROUND AND AIMS

Although molecular analysis of pancreatic cyst fluid may aid pancreatic cyst classification, clinical practice remains highly variable. Therefore, we performed a systematic review and meta-analysis to evaluate the diagnostic performance of KRAS and GNAS mutations in EUS-acquired pancreatic cyst fluid for diagnosis of intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic lesions (MCLs).

METHODS

Individualized searches were developed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines and meta-analysis analyzed according to the Cochrane Diagnostic Test Accuracy working group methodology. A bivariate model was used to compute the pooled sensitivity and specificity and to plot the summary receiver operating characteristics curve with summary point and corresponding 95% confidence interval (95% CI).

RESULTS

Six studies (785 lesions) were included. For IPMNs and MCLs, KRAS + GNAS (combination) had significantly higher diagnostic accuracy than KRAS alone and GNAS alone (all P < .001). The pooled sensitivity, specificity, and diagnostic accuracy of KRAS + GNAS mutations for diagnosis of IPMNs were 94% (95% CI, 72-99; I² = 86.74%), 91% (95% CI, 72-98; I² = 89.83), and 97% (95% CI, 95-98), respectively, with each significantly higher compared with carcinoembryonic antigen (CEA) alone (all P < .001). For diagnosis of MCLs, KRAS + GNAS had a similar sensitivity and specificity compared with CEA alone; however, diagnostic accuracy was significantly improved (97% [95% CI, 95-98] vs 89% [95% CI, 86-91]; P < .001).

CONCLUSIONS

Molecular analysis for KRAS + GNAS mutations in EUS-acquired pancreatic cyst fluid has high sensitivity and specificity with significantly improved diagnostic accuracy for diagnosis of IPMNs and MCLs when compared with CEA alone.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas: recommendations for Standardized Imaging and Reporting from the Society of Abdominal Radiology IPMN disease focused panel

There have been many publications detailing imaging features of malignant transformation of intraductal papillary mucinous neoplasms (IPMN), management and recommendations for imaging follow-up of diagnosed or presumed IPMN. However, there is no consensus on several practical aspects of imaging IPMN that could serve as a clinical guide for radiologists and enable future data mining for research. These aspects include how to measure IPMN, define reporting terminology, standardize reporting and unify guidelines for surveillance. The Society of Abdominal Radiology (SAR) created multiple Disease-Focused Panels (DFP) comprised multidisciplinary panel members who focus on a particular disease, with the goal to develop ways for radiologists to improve patient care, education, and research. DFP members met to identify the current controversies and limitations of imaging pancreatic IPMN. This paper aims to provide a practical review of the key imaging characteristics of IPMN for trainees and practicing radiologists, to guide uniformity of performance and interpretation of surveillance imaging studies, and to improve communication with clinicians by providing a lexicon and reporting template based on the experience of the SAR-DFP panel members.

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.

Quality assessment for systematic reviews and meta-analyses of cohort studies

BACKGROUND AND AIMS

There is a growing need for valid, efficient, and easy scoring scales to rate the quality of cohort studies. We aimed to develop and validate a quality assessment score to be used for cohort studies.

METHODS

We followed a rigorous process to establish content, face, and construct validity. Most questions were scored at 0 or 1. Inter-rater reliability and test-retest reliability were assessed using the Spearman correlation coefficient (r_s) and Cohen's κ statistic. Internal consistency was measured using the Kuder-Richardson formula 20 (KR20).

RESULTS

The final tool consists of 9 questions with a maximum score of 10. The inter-rater reliability was high with the Spearman correlation coefficient (r_s = .66). Agreement for inclusion was 90%. Test-retest reliability was high. For rater 1, r_s = .91, κ = .38 for scores, and κ = 1 for inclusion. For rater 2, r = .94, 80% agreement for scores, and 100% agreement for inclusion. Internal consistency was reasonable based on 2 studies: KR20 = .21 and KR20 = .65. The novel scale rated highest in efficiency, understandably, ease of use, and ease of interpretation when compared with 3 other scales.

CONCLUSIONS

This novel scale has favorable performance characteristics, is efficient to conduct, and is easy to interpret and will be very helpful for physicians and researchers conducting systematic reviews and meta-analyses.

Application of EUS-based techniques in the evaluation of pancreatic cystic neoplasms

Pancreatic cystic neoplasms (PCNs) are being detected increasingly frequently due to the widespread use of high-resolution abdominal imaging modalities. Some subtypes of PCNs have the potential for malignant transformation. Therefore, accurate diagnosis of PCNs is crucial to determine whether surgical resection or surveillance is the best management strategy. However, the current cross-section imaging modalities are not accurate enough to enable definite diagnoses. In the last decade, EUS-based techniques have emerged, aiming to overcome the limitations of standard cross-section imaging modalities. These novel EUS-based techniques were primarily designed to acquire distinct images to make radiological diagnoses, collect cyst fluid to undergo biochemical or molecular analyses, and obtain tissue to conclude the pathological diagnoses. In this article, we present a comprehensive and critical review of these emerging EUS techniques for the diagnosis of PCNs, with emphasis being placed on the advantages, feasibilities, diagnostic performances, and limitations of these novel techniques.

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.

EUS-guided biopsy versus confocal laser endomicroscopy in patients with pancreatic cystic lesions: A systematic review and meta-analysis

Background and Objectives:

Pancreatic cystic lesions (PCLs) are frequent incidental findings on cross-sectional imaging and represent a diagnostic challenge as different kinds of PCLs harbor a dissimilar risk of malignancy. Two diagnostic tools have recently been developed and introduced: through-the-needle biopsy (TTNB) and needle-based confocal laser endomicroscopy (nCLE). The aim of this meta-analysis was to compare the diagnostic yield and performance, as well as the safety profile of the two methods.

Methods:

This meta-analysis was performed in accordance with the PRISMA statement. Medline, Embase, Web of Science, and Cochrane Library databases were searched for studies with five or more patients undergoing either endoscopic ultrasound (EUS)-TTNB or EUS-nCLE for a PCL. Reviews, case reports, editorials, conference abstracts, and studies on exclusively solid pancreatic lesions were excluded. Outcomes of interest were diagnostic yield and performance, safety, and technical success.

Results:

Twenty studies with 1023 patients were included in the meta-analysis. Pooled diagnostic yield of EUS-nCLE was higher compared to EUS-TTNB (85% vs. 74%, P < 0.0001), while diagnostic performance was high and comparable for both methods (pooled sensitivity: 80% vs. 86% and pooled specificity: 80% vs. 83% for TTNB and nCLE, respectively, P > 0.05). Pooled estimate of total adverse event (AE) rate was 5% in the TTNB group and 3% in the nCLE group, P = 0.302. Technical success rates were high and comparable (94% and 99% for EUS-TTNB and nCLE, respectively; P = 0.07).

Conclusion:

EUS-TTNB and EUS-nCLE have a similar safety profile with a relatively low number of AEs. Technical success, sensitivity, and specificity are comparable; however, EUS-nCLE seems to have a slightly higher diagnostic yield.

Cyst Fluid Carcinoembryonic Antigen Level Difference between Mucinous Cystic Neoplasms and Intraductal Papillary Mucinous Neoplasms

BACKGROUND/AIMS

The role of cyst fluid carcinoembryonic antigen (CEA) level in differentiating mucinous pancreatic cystic lesions (PCLs) is controversial. We investigated the role of cyst fluid CEA in differentiating low-risk (LR)-intraductal papillary mucinous neoplasms (IPMNs) from high-risk (HR)-IPMNs and LR-mucinous cystic neoplasms (MCNs).

METHODS

This was a retrospective study of 466 patients with PCLs who underwent endoscopic ultrasound-guided fine-needleaspiration over a 7-year period. On histology, low-grade dysplasia and intermediate-grade dysplasia were considered LR, whereas high-grade dysplasia and invasive carcinoma were considered HR.

RESULTS

Data on cyst fluid CEA levels were available for 50/102 mucinous PCLs with definitive diagnoses. The median CEA (range) levels were significantly higher in HR cysts than in LR cysts (2,624 [0.5-266,510] ng/mL vs. 100 [16.8-53,445]ng/mL, p=0.0012). The area under the receiver operating characteristic curve (AUROC) was 0.930 (95% confidence interval [CI], 0.5-0.8; p<0.001) for differentiating LR-IPMNs from LR-MCNs. The AUROC was 0.921 (95% CI, 0.823-1.000; p<0.001) for differentiating LR-IPMNs from HR-IPMNs. Both had a CEA cutoff level of >100ng/mL, with a negative predictive value (NPV) of 100%.

CONCLUSION

Cyst fluid CEA levels significantly vary between LR-IPMNs, LR-MCNs, and HR-IPMNs. A CEA cutoff level of >100ng/mL had a 100% NPV in differentiating LR-IPMNs from LR-MCNs and HR-IPMNs.

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.

Diagnostic yield of EUS-guided through-the-needle biopsy in pancreatic cysts: a meta-analysis

BACKGROUND AND AIMS

There is currently limited evidence supporting the use of EUS-guided through-the-needle biopsy for sampling pancreatic cystic lesions. The aim of this meta-analysis was to provide a pooled estimate of the diagnostic performance of through-the-needle biopsy for sampling of pancreatic cysts.

METHODS

A bibliographic search on the main databases was performed in September 2019. Pooled effects were calculated using a random-effects model by means of the DerSimonian and Laird test. The primary outcome was sample adequacy. Additional endpoints were diagnostic accuracy, optimal histologic core procurement, mean number of needle passes, pooled specificity, and sensitivity. Adverse event rates were also analyzed.

RESULTS

Eleven studies enrolling 490 patients were included. Eight articles compared through-the-needle biopsy with cytology/cystic fluid analysis. Most patients were female, and the body/tail was the most frequent location of cystic lesions. Sample adequacy with through-the-needle biopsy was 85.3% (78.2%-92.5%), and subanalysis performed according to cyst morphology, size, and location confirmed the result. Through-the-needle biopsy clearly outperformed FNA both in terms of sample adequacy (odds ratio, 4.83; 95% confidence interval, 1.63-14.31; P =.004) and diagnostic accuracy (odds ratio, 3.44; 95% confidence interval, 1.32-8.96; P =.01). The pooled diagnostic accuracy rate, sensitivity, and specificity of through-the-needle biopsy were 78.8%, 82.2%, and 96.8%, respectively. A mean of 3.121 (2.98-3.25) passes through the cyst was needed to obtain adequate histologic samples. The incidence rates of mild bleeding and pancreatitis were 4% and 2%, respectively.

CONCLUSION

Our meta-analysis speaks in favor of the use of through-the-needle biopsy as a safe and effective tool in EUS-guided tissue acquisition of pancreatic cysts.

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.

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.

Management of Incidental Pancreatic Cystic Lesions: Integrating Novel Diagnostic and Prognostic Factors With Current Clinical Guidelines

Owing to increased detection rates, the diagnosis and management of incidental pancreatic cysts has become a common predicament. Up to 13% of patients undergoing cross-sectional imaging studies for other indications are found to have pancreatic cystic lesions. Although most cystic lesions are benign, the malignant potential of several types of pancreatic cysts makes accurate classification vital to directing therapy. To this end, advances in the last decade led to better characterization of pancreatic cyst morphology and hence enhanced the ability to predict underlying histopathology, and biological behavior. Although accurate classification remains a challenge, the utilization of complementary diagnostic tools is the optimal approach to dictate management. The following review includes a description of pancreatic cysts, a critical review of current and emerging diagnostic techniques and a review of recent guidelines in the management of incidental pancreatic cysts.

White paper on pancreatic ductal adenocarcinoma from society of abdominal radiology's disease-focused panel for pancreatic ductal adenocarcinoma: Part II, update on imaging techniques and screening of pancreatic cancer in high-risk individuals

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive gastrointestinal malignancy with a poor 5-year survival rate. Its high mortality rate is attributed to its aggressive biology and frequently late presentation. While surgical resection remains the only potentially curative treatment, only 10-20% of patients will present with surgically resectable disease. Over the past several years, development of vascular bypass graft techniques and introduction of neoadjuvant treatment regimens have increased the number of patients who can undergo resection with a curative intent. While the role of conventional imaging in the detection, characterization, and staging of patients with PDAC is well established, its role in monitoring treatment response, particularly following neoadjuvant therapy remains challenging because of the complex anatomic and histological nature of PDAC. Novel morphologic and functional imaging techniques (such as DECT, DW-MRI, and PET/MRI) are being investigated to improve the diagnostic accuracy and the ability to measure response to therapy. There is also a growing interest to detect PDAC and its precursor lesions at an early stage in asymptomatic patients to increase the likelihood of achieving cure. This has led to the development of pancreatic cancer screening programs. This article will review recent updates in imaging techniques and the current status of screening and surveillance of individuals at a high risk of developing PDAC.

Endoscopic Ultrasound-Guided Confocal Laser Endomicroscopy Increases Accuracy of Differentiation of Pancreatic Cystic Lesions

BACKGROUND & AIMS

Imaging patterns from endoscopic ultrasound (EUS)-guided needle-based confocal laser endomicroscopy (nCLE) have been associated with specific pancreatic cystic lesions (PCLs). We compared the accuracy of EUS with nCLE in differentiating mucinous from nonmucinous PCLs with that of measurement of carcinoembryonic antigen (CEA) and cytology analysis.

METHODS

We performed a prospective study of 144 consecutive patients with a suspected PCL (≥20 mm) who underwent EUS with fine-needle aspiration of pancreatic cysts from June 2015 through December 2018 at a single center; 65 patients underwent surgical resection. Surgical samples were analyzed by histology (reference standard). During EUS, the needle with the miniprobe was placed in the cyst, which was analyzed by nCLE. Fluid was aspirated and analyzed for level of CEA and by cytology. We compared the accuracy of nCLE in differentiating mucinous from nonmucinous lesions with that of measurement of CEA and cytology analysis.

RESULTS

The mean size of dominant cysts was 36.4 ± 15.7 mm and the mean duration of nCLE imaging was 7.3 ± 2.8 min. Among the 65 subjects with surgically resected cysts analyzed histologically, 86.1% had at least 1 worrisome feature based on the 2012 Fukuoka criteria. Measurement of CEA and cytology analysis identified mucinous PCLs with 74% sensitivity, 61% specificity, and 71% accuracy. EUS with nCLE identified mucinous PCLs with 98% sensitivity, 94% specificity, and 97% accuracy. nCLE was more accurate in classifying mucinous vs nonmucinous cysts than the standard method (P < .001). The overall incidence of postprocedure acute pancreatitis was 3.5% (5 of 144); all episodes were mild, based on the revised Atlanta criteria.

CONCLUSIONS

In a prospective study, we found that analysis of cysts by nCLE identified mucinous cysts with greater accuracy than measurement of CEA and cytology analysis. EUS with nCLE can be used to differentiate mucinous from nonmucinous PCLs. ClincialTrials.gov no: NCT02516488.

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.

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.

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

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

Endoscopic ultrasonography for the evaluation of pancreatic cystic neoplasms

Endoscopic ultrasonography (EUS) is a modality with high spatial resolution that enables comprehensive observation of the entire pancreas and plays an important role in the diagnosis of pancreatic lesions. Recent advances in diagnostic imaging methods such as ultrasound, computed tomography, and magnetic resonance imaging have increased the incidental detection of pancreatic cystic lesions (PCLs). EUS has been recognized as an essential diagnostic method for the detection and evaluation of PCLs. EUS has two important roles: as a detailed (high-resolution) imaging diagnostic method and as an approach for collecting cyst fluid content by EUS-guided fine needle aspiration for pathological diagnosis or biomarker evaluation. Furthermore, in recent years, the usefulness of contrast-enhanced EUS for the differential diagnosis of PCLs or evaluation of grade of malignancy, and a novel imaging technique called needle-based confocal laser endomicroscopy to observe intraductal structures through a needle, has been reported. An understanding of the morphological characteristics of PCLs depicted by ultrasound imaging and of the benefits and limitations of EUS diagnosis in daily practice is needed.

Pancreatic Cysts: Diagnostic Role of EUS-Guided Microforceps Biopsy and Confocal Laser Endomicroscopy

Frequent use of high-quality cross-sectional imaging has led to a significant rise in diagnosis of pancreatic cystic lesions (PCLs). Despite the fact that enormous effort has been put into the research of PCLs within the last two decades and multiple guidelines have been developed, our clinical decision-making especially in regard to mucinous lesions remains limited. Currently, clinical assessment, cross-sectional imaging and EUS with fluid analysis (if appropriate) belong to the standard care in patients with PCLs. For differentiation of mucinous from nonmucinous cysts, the sensitivity of cytological investigation and CEA in the cyst fluid is 42% and 52-79%, respectively. Due to the limited accuracy, further diagnostic tools are warranted. Two EUS-guided approaches have been introduced recently. Through-the-(19-gauge EUS) needle Moray microforceps have been developed, and several studies have acknowledged their contribution to the correct diagnosis as they help to overcome limited cellularity of the EUS-guided cyst fluid aspiration and traditional cytology. Confocal laser endomicroscopy offers real-time images and seems to be a promising method for the diagnosis and differential diagnosis of pancreatic PCLs. Example images of the needle-based confocal laser endomicroscopy criteria for the diagnosis of PCLs have been suggested recently. Before both, Moray microforceps and confocal laser endomicroscopy can be widely accepted, further studies are necessary to determine the real diagnostic yield and the clinical efficacy.

Position statement on EUS-guided ablation of pancreatic cystic neoplasms from an international expert panel

Background and aim  Recently, several guidelines with divergent recommendations on management of pancreatic cystic neoplasm have been published but the role of endoscopic ultrasound (EUS)-guided pancreatic cyst ablation has not been thoroughly addressed. The aim of the current paper is to explore the issues surrounding EUS-guided pancreatic cyst ablation by generating a list of clinical questions and providing answers based on best scientific evidence available. Methods  An expert panel in EUS-guided pancreatic cyst ablation was recruited from members of the Asian EUS group and an international expert panel. A list of clinical questions was created and each question allocated to one member to generate a statement in response. The statements were then discussed in three Internet conference meetings between October 2016 and October 2017. The statements were changed until consensus was obtained. Afterwards, the complete set of statements was sent to all the panelist to vote on strength of the statements, classification of the statement sand grading of the evidence. Results  Twenty-three statements on EUS-guided drainage of pancreatic cyst ablation were formulated. The statements addressed indications for the procedures, technical aspects, pre-procedure and post-procedure management, management of complications, and competency and training in the procedures. Conclusion  The current set of statements on EUS-guided pancreatic cyst ablation are the first to be published by any endoscopic society. Clinicians interested in developing the technique should reference these statements and future studies should address the key issues raised in the document.

Endoscopic diagnosis of pancreatic cysts

PURPOSE OF REVIEW

Pancreatic cystic lesions (PCLs) are increasingly identified on abdominal imaging. Given the malignant potential of certain cyst subtypes and the poor survival rates of pancreatic cancer, accurate diagnosis and appropriate management of these cysts are critical.

RECENT FINDINGS

Advances in endoscopic ultrasound (EUS)-guided diagnostics have increased the accuracy of differentiating PCLs. These include cyst fluid molecular analysis, EUS-guided needle-based confocal laser endomicroscopy, and EUS-guided through the needle microforceps biopsy. This review encapsulates recent advances in the endoscopic management of PCLs with a specific focus on EUS-guided diagnosis.

SUMMARY

It is important to accurately diagnose pancreatic cystic lesions with malignant potential where the definitive management is surgical resection. Misdiagnosis can result in inadvertent surgery of an otherwise benign lesion or malignant progression of a precancerous cyst. Moreover, pancreatic surgery is associated with significant morbidity and mortality. Recent advances in EUS-guided tissue acquisition, imaging, and molecular biomarkers have resulted in improved diagnostic accuracy of pancreatic cystic lesions. Future studies need to define efficient and accurate diagnostic algorithms for improved management of pancreatic cysts.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Setting minimum standards for training in EUS and ERCP: results from a prospective multicenter study evaluating learning curves and competence among advanced endoscopy trainees

BACKGROUND AND AIMS

Minimum EUS and ERCP volumes that should be offered per trainee in "high quality" advanced endoscopy training programs (AETPs) are not established. We aimed to define the number of procedures required by an "average" advanced endoscopy trainee (AET) to achieve competence in technical and cognitive EUS and ERCP tasks to help structure AETPs.

METHODS

American Society for Gastrointestinal Endoscopy (ASGE)-recognized AETPs were invited to participate; AETs were graded on every fifth EUS and ERCP examination using a validated tool. Grading for each skill was done using a 4-point scoring system, and learning curves using cumulative sum analysis for overall, technical, and cognitive components of EUS and ERCP were shared with AETs and trainers quarterly. Generalized linear mixed-effects models with a random intercept for each AET were used to generate aggregate learning curves, allowing us to use data from all AETs to estimate the average learning experience for trainees.

RESULTS

Among 62 invited AETPs, 37 AETs from 32 AETPs participated. Most AETs reported hands-on EUS (52%, median 20 cases) and ERCP (68%, median 50 cases) experience before starting an AETP. The median number of EUS and ERCPs performed per AET was 400 (range, 200-750) and 361 (range, 250-650), respectively. Overall, 2616 examinations were graded (EUS, 1277; ERCP-biliary, 1143; pancreatic, 196). Most graded EUS examinations were performed for pancreatobiliary indications (69.9%) and ERCP examinations for ASGE biliary grade of difficulty 1 (72.1%). The average AET achieved competence in core EUS and ERCP skills at approximately 225 and 250 cases, respectively. However, overall technical competence was achieved for grade 2 ERCP at about 300 cases.

CONCLUSION

The thresholds provided for an average AET to achieve competence in EUS and ERCP may be used by the ASGE and AETPs in establishing the minimal standards for case volume exposure for AETs during their training. (Clinical trial registration number: NCT02509416.).

Needle Biopsy Adequacy in the Era of Precision Medicine and Value-Based Health Care

CONTEXT.—

Needle biopsy of diseased tissue is an essential diagnostic tool that is becoming even more important as precision medicine develops. However, the capability of this modality to efficiently provide samples adequate for diagnostic and prognostic analysis remains quite limited relative to current diagnostic needs. For physicians and patients, inadequate biopsy frequently leads to diagnostic delay, procedure duplication, or insufficient information about tumor biology leading to delay in treatment; for health systems, this results in substantial incremental costs and inefficient use of scarce specialized diagnostic resources.

OBJECTIVE.—

To review current needle biopsy technology, devices, and practice with a perspective to identify current limitations and opportunities for improvement in the context of advancing precision medicine.

DATA SOURCES.—

PubMed searches of fine-needle aspiration and core needle biopsy devices and similar technologies were made generally, by tissue site, and by adequacy as well as by health economics of these technologies.

CONCLUSIONS.—

Needle biopsy adequacy can be improved by recognizing the importance of this diagnostic tool by promoting common criteria for needle biopsy adequacy; by optimizing needle biopsy procedural technique, technologies, clinical practice, professional education, and quality assurance; and by bundling biopsy procedure costs with downstream diagnostic modalities to provide better accountability and incentives to improve the diagnostic process.

Survey Study on the Practice Patterns of the Evaluation and Management of Incidental Pancreatic Cysts

BACKGROUND AND AIMS

Various gastrointestinal societies have released guidelines on the evaluation of asymptomatic pancreatic cysts (PCs). These guidelines differ on several aspects, which create a conundrum for clinicians. The aim of this study was to evaluate preferences and practice patterns in the management of incidental PCs in light of these societal recommendations.

METHODS

An electronic survey distributed to members of the American Society for Gastrointestinal Endoscopy (ASGE). Main outcomes included practice setting (academic vs. community), preferences for evaluation, management, and surveillance strategies for PCs.

RESULTS

A total of 172 subjects completed the study (52% academic-based endoscopists). Eighty-six (50%) and 138 (80%) of the participants responded that they would recommend EUS surveillance of incidental PCs measuring less than 2 cm and 3 cm, respectively. Nearly half of the endosonographers (42.5% community and 44% academic; p = 1.0) would routinely perform FNA on PCs without any high-risk features. More academic-based endoscopists (57% academic vs. 32% community; p = 0.001) would continue incidental PC surveillance indefinitely.

CONCLUSIONS

There is significant variability in the approach of incidental PCs among clinicians, with practice patterns often diverging from the various GI societal guideline recommendations. Most survey respondents would routinely recommend EUS-FNA and indefinite surveillance for incidental PCs without high-risk features. The indiscriminate use of EUS-FNA and indefinite surveillance of all incidental PCs is not cost-effective, exposes the patient to unnecessary testing, and can further perpetuate diagnostic uncertainty. Well-designed studies are needed to improve our diagnostic and risk stratification accuracy in order to formulate a consensus on the management of these incidental PCs.

Tissue acquisition in pancreatic cystic lesions

Despite the progress achieved by scientific research in recent years, pancreatic cystic lesions (PCLs) remain a challenging clinical problem. A significant percentage of benign PCLs are still wrongly sent to surgery, with all the related risks of a high number of surgery-related complications and mortality. Diagnosis of the type of PCL, and risk stratification for malignancy are essential for a correct management of these lesions. Several guidelines have identified some clinical and morphological aspects suggesting the need for more accurate exams. Endoscopic ultrasound fine needle aspiration (EUS-FNA) of cystic fluid for cytology is the advised method of tissue acquisition in several guidelines, and the most used technique around the world. However sensitivity and adequacy of this technique are limited by the low amount of cells dispersed in cystic fluid. Alternative techniques have been tested to target the cystic walls in an attempt to obtain microhistologic specimens in order to augment the probability of obtaining an adequate diagnostic sample. The aim of this review is to offer a critical overview of the existing literature on tissue acquisition in PCLs, and emphasize advantages and disadvantages of each technique, and unclear areas that need to be investigated with future research.

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.

Endoscopic diagnosis of cystic lesions of the pancreas

Endoscopic methods are increasingly used in the diagnosis of cystic lesions of the pancreas. The two major endoscopic approaches are endoscopic ultrasonography (EUS) and transpapillary diagnosis. EUS-guided fine-needle aspiration cytology and EUS-guided fine needle-based confocal laser endomicroscopy have been used in the differential diagnosis of mucinous and non-mucinous pancreatic cysts. EUS is the most sensitive modality for detecting mural nodules (MN) in intraductal papillary mucinous neoplasms (IPMN). Contrast-enhanced harmonic EUS (CH-EUS), as an add-on to EUS, is useful for identifying and characterizing MN. Recent studies show that CH-EUS has a sensitivity of 60-100% and a specificity of 75-92.9% for diagnosing malignant cysts. Intraductal ultrasonography and peroral pancreatoscopy are especially useful for detecting MN and IPMN. A recent meta-analysis showed that cytological assessment of pancreatic juice using a transpapillary approach had a pooled sensitivity, specificity, and accuracy of 35.1%, 97.2%, and 92.9%, respectively, for diagnosing malignant IPMN. Further studies are warranted to determine the indications for each of these novel techniques in assessing cystic lesions of the pancreas.