A prospective, comparative trial to optimize sampling techniques in EUS-guided FNA of solid pancreatic masses

Updated techniques and evidence for endoscopic ultrasound-guided tissue acquisition from solid pancreatic lesions

Endoscopic ultrasound-guided tissue acquisition (EUS-TA), including fine-needle aspiration (EUS-FNA) and fine-needle biopsy (EUS-FNB), has revolutionized specimen collection from intra-abdominal organs, especially the pancreas. Advances in personalized medicine and more precise treatment have increased demands to collect specimens with higher cell counts, while preserving tissue structure, leading to the development of EUS-FNB needles. EUS-FNB has generally replaced EUS-FNA as the procedure of choice for EUS-TA of pancreatic cancer. Various techniques have been tested for their ability to enhance the diagnostic performance of EUS-TA, including multiple methods of sampling at the time of puncture, on-site specimen evaluation, and specimen processing. In addition, advances in next-generation sequencing have made comprehensive genomic profiling of EUS-TA samples feasible in routine clinical practice. The present review describes updates in EUS-TA sampling techniques of pancreatic lesions, as well as methods for their evaluation.

High-Performance PMN-PT Single-Crystal-Based 1-3 Composite Transducer Integrated with a Biopsy Needle

To address the need for high-resolution imaging in lung nodule detection and overcome the limitations of the shallow imaging depth associated with high-frequency ultrasound and the complex structure of lung tissue, we successfully integrated 50 MHz ultrasound transducers with 18-gauge biopsy needles. Featuring a miniaturized size of 0.6 × 0.5 × 0.5 mm3, the 50 MHz micromachined 1-3 composite transducer was tested to perform mechanical scanning of a nodule within a lung-tissue-mimicking phantom in vitro. The high-frequency transducer demonstrated the ability to achieve imaging with an axial resolution of 30 μm for measuring nodule edges. Moreover, the integrated biopsy needle prototype exhibited high accuracy (1.74% discrepancy) in estimating nodule area compared to actual dimensions in vitro. These results underscore the promising potential of biopsy-needle-integrated transducers in enhancing the accuracy of endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNA) for clinical applications.

Role of Endoscopic Ultrasound in Diagnosis of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most common (90%) type of solid pancreatic neoplasm. Due to its late presentation and poor survival rate, early diagnosis and timely treatment is of utmost importance for better clinical outcomes. Endoscopic ultrasound provides high-resolution images of the pancreas and has excellent sensitivity in the diagnosis of even small (<2 cm) pancreatic lesions. Apart from imaging, it also has an advantage of tissue acquisition (EUS fine-needle aspiration, FNA; or fine-needle biopsy, FNB) for definitive diagnoses. EUS-guided tissue acquisition plays a crucial role in genomic and molecular studies, which in today's era of personalized medicine, are likely to become important components of PDAC management. With the use of better needle designs and technical advancements, EUS has now become an indispensable tool in the management of PDAC. Lastly, artificial intelligence for the detection of pancreatic lesions and newer automated needles for tissue acquisition will obviate observer dependency in the near future, resulting in the wider dissemination and adoption of this technology for improved outcomes in patients with PDAC.

Comparing fine needle biopsy techniques in solid pancreatic lesions: A prospective randomized study

INTRODUCTION

Endoscopic ultrasound-guided fine-needle biopsies (EUS-FNB) are the best technique for sampling solid pancreatic lesions. However, the most appropriate biopsy technique has not been standardized using Fine Needle Biopsy (FNB) needles. The aim of this work was to identify the best biopsy technique to achieve the best tissue integrity and cause the least blood contamination.

MATERIAL AND METHODS

Patients ≥18 years of age with solid pancreatic lesions who underwent EUS-FNB at our institution from January 2020 to May 2021 were consecutively selected. Three passes were performed with each of the threee techniques to obtain tissue: suction with 10 ml of vacuum, capillary, and wet. An independent pathologist evaluated the received tissue integrity and the degree of blood contamination of each sample according to scales.

RESULTS

Seventy-five patients were recruited for our study. A superior tissue integrity was observed using the wet-suction technique in lesions located in the body and/or tail of the pancreas, and an average score of 4.40 (p = 0.027) was assigned for this technique. Regarding the contamination of the sample in the whole cohort, the simple-suction technique shown a higher contamination, 1.55 (p < 0.001). There was no statistically significant difference among the techniques when evaluating tissue integrity or contamination in lesions larger or smaller than 3 cm.

CONCLUSION

When performing EUS-FNB for solid pancreatic lesions located in the head/uncinated process, the three methods provided similar diagnostic yields. The wet-suction technique had a higher score in tissue integrity when lesions were located in the body and/or tail of the pancreas.

The Wet Suction Technique Enhances the Diagnostic Efficacy and Aspirate Quality of EUS-FNA for Solid Lesions: A Multicenter Retrospective Study in China

GOALS

To comprehensively compare the wet suction technique with the conventional dry suction technique for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in solid lesions.

BACKGROUND

Optimal suction techniques for EUS-FNA remain uncertain when approaching solid lesions.

STUDY

We performed a retrospective study of EUS-FNA at 3 medical centers in China. A total of 203 patients were enrolled who received 2 passes of EUS-FNA with 22-G needles. If the first pass underwent dry suction, the second pass was wet suction. Otherwise, the order of suction technique is opposite. Diagnostic accuracy, sample quality (including cellularity and blood contamination), and sample quantity (including specimen adequacy, the maximum intact specimen length, and the total specimen length) were compared between wet-suction and dry-suction techniques.

RESULTS

The patients included 143 pancreatic lesions and 60 nonpancreatic lesions. Compared with the dry suction technique, the wet suction technique yielded a significantly higher diagnostic accuracy (85.22% vs. 72.41%, P =0.002), better specimen adequacy score and cellularity score ( P <0.0001), and lower blood contamination score ( P <0.0001). In the subgroup analysis, wet suction provided significantly higher diagnostic accuracy in pancreatic cancer without chronic pancreatitis ( P <0.05), and better cellularity score and specimen adequacy score, lower blood contamination score, and longer maximum intact specimen length and total specimen length in various lesions than that in dry suction.

CONCLUSIONS

The wet suction technique resulted in significantly higher diagnostic accuracy in pancreatic cancer without chronic pancreatitis, and better cellularity and histologic specimen in most of solid lesions.

Comprehensive review on endoscopic ultrasound-guided tissue acquisition techniques for solid pancreatic tumor

Pancreatic ductal adenocarcinoma is speculated to become the second leading cause of cancer-related mortality by 2030, a high mortality rate considering the number of cases. Surgery and chemotherapy are the main treatment options, but they are burdensome for patients. A clear histological diagnosis is needed to determine a treatment plan, and endoscopic ultrasound (EUS)-guided tissue acquisition (TA) is a suitable technique that does not worsen the cancer-specific prognosis even for lesions at risk of needle tract seeding. With the development of personalized medicine and precision treatment, there has been an increasing demand to increase cell counts and collect specimens while preserving tissue structure, leading to the development of the fine-needle biopsy (FNB) needle. EUS-FNB is rapidly replacing EUS-guided fine-needle aspiration (FNA) as the procedure of choice for EUS-TA of pancreatic cancer. However, EUS-FNA is sometimes necessary where the FNB needle cannot penetrate small hard lesions, so it is important clinicians are familiar with both. Given these recent dev-elopments, we present an up-to-date review of the role of EUS-TA in pancreatic cancer. Particularly, technical aspects, such as needle caliber, negative pressure, and puncture methods, for obtaining an adequate specimen in EUS-TA are discussed.

Optimal sampling technique for EUS-guided fine-needle biopsy of solid pancreatic lesions using a 25-gauge ProCore needle: A multicenter randomized crossover superiority study

Background and Objectives

It remains unclear whether the use of the stylet slow-pull (SP) and wet suction (WS) can improve the yield of endoscopic ultrasound-guided fine-needle biopsy compared to standard suction (SS). The aim of this study was to compare the diagnostic efficacy of the three sampling techniques when using 25G ProCore needles for solid pancreatic lesions.

Materials and Methods

This multicenter single-blind randomized crossover superiority trial enrolled patients with solid pancreatic lesions (n = 300) from four digestive endoscopic centers in China. All three sampling techniques were performed on each patient using a 25G ProCore needle in a randomized sequence. The diagnostic efficacy, the specimen yield, and quality of each technique, the overall technical success rate and diagnostic yield of the 25G ProCore needle, and rate of adverse events were evaluated.

Results

A total of 291 patients were analyzed. No significant difference was found in diagnostic efficiency among the three techniques (sensitivity, 82.14% vs. 75.00% vs. 77.86, P = 0.1186; accuracy, 82.82% vs. 75.95% vs. 78.69%, P = 0.1212). The SP had an inferior tissue integrity compared to the SS and WS techniques (71.82% vs. 62.55% vs. 69.76%, P = 0.0096). There was no significant difference in the degree of blood contamination among the three groups (P = 0.2079). After three passes, the overall sensitivity was 93.93%, and the accuracy was 94.16%.

Conclusions

SS and WS techniques are better choices than SP technique for 25G ProCore needle, for they could provide higher specimen adequacy without increasing the amount of blood contamination. The 25G ProCore needle can provide a satisfactory diagnostic yield for solid pancreatic lesions.

Diagnostic performance of endoscopic ultrasound-guided tissue acquisition by EUS-FNA versus EUS-FNB for solid pancreatic mass without ROSE: a retrospective study

BACKGROUND

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is an established diagnostic procedure for solid pancreatic mass. However, the diagnostic yield between fine-needle aspiration (FNA) and fine-needle biopsy (FNB) remains unclear. We aimed to evaluate and compare the diagnostic yields between FNA and FNB using conventional FNA and Franseen needles of the same size 22-gauge needle, in patients with solid pancreatic mass who underwent EUS-TA without rapid onsite cytopathology evaluation (ROSE).

METHODS

All cases of EUS-TA by FNA or FNB for solid pancreatic mass between January 2017 and October 2020 in a single-centre university hospital were retrospectively reviewed. All procedures were performed without an onsite cytologist. Before the endoscopist finished the procedure, macroscopic onsite evaluation (MOSE) was confirmed. The diagnostic yield and the average number of needle passes between FNB and FNA were then compared.

RESULTS

A total of 151 patients (FNA, n = 77; FNB, n = 74) with solid pancreatic mass detected by cross-sectional imaging underwent EUS-TA. The mean age was 62.3 ± 12.8 years, with 88 (58.3%) males. Age, sex, mass location, tumour size and disease stage from imaging were not significantly different between the two groups. The diagnostic performance was higher in EUS-FNB (94.6%) than in EUS-FNA (89.6%). The mean number of needle passes was clearly fewer in FNB than in FNA (2.8 vs. 3.8, p < 0.001). The total procedure time was shorter in FNB (34.7 min) than in FNA (41 min). The adverse event rate between FNB and FNA was not significantly different.

CONCLUSIONS

The diagnostic yield of solid pancreatic mass was higher in FNB using the Franseen needle than in FNA using the conventional FNA needle in a centre where ROSE is unavailable, without serious adverse event. In addition, FNB had fewer needle passes and shorter total procedure time.

The Role of Endoscopic Ultrasonography in the Diagnosis and Staging of Pancreatic Cancer

Pancreatic cancer is the fourth leading cause of cancer-related death and the second gastrointestinal cancer-related death in the United States. Early detection and accurate diagnosis and staging of pancreatic cancer are paramount in guiding treatment plans, as surgical resection can provide the only potential cure for this disease. The overall prognosis of pancreatic cancer is poor even in patients with resectable disease. The 5-year survival after surgical resection is ~10% in node-positive disease compared to ~30% in node-negative disease. The advancement of imaging studies and the multidisciplinary approach involving radiologists, gastroenterologists, advanced endoscopists, medical, radiation, and surgical oncologists have a major impact on the management of pancreatic cancer. Endoscopic ultrasonography is essential in the diagnosis by obtaining tissue (FNA or FNB) and in the loco-regional staging of the disease. The advancement in EUS techniques has made this modality a critical adjunct in the management process of pancreatic cancer. In this review article, we provide an overall description of the role of endoscopic ultrasonography in the diagnosis and staging of pancreatic cancer.

Optimal Techniques for EUS-Guided Fine-Needle Aspiration of Pancreatic Solid Masses at Facilities without On-Site Cytopathology: Results from Two Prospective Randomised Trials

Background: EUS-guided fine-needle aspiration (EUS-FNA) has emerged as the primary modality for the cytologic diagnosis of pancreatic solid masses. The aim of this study is to determine whether technical factors including suction (S), non-suction (NS), capillary sampling with stylet slow-pull (CSSS), and the number of needle actuations (to-and-fro needle movements) may affect the accuracy of EUS-FNA for pancreatic solid masses at facilities without on-site cytopathology. Methods: The diagnostic yield of malignancy, blood contamination and cellularity at each sample acquired from EUS-FNA with or without S and different numbers of actuation (10, 15 and 20) were measured (study I). The optimal actuation number was determined and a head-to-head comparison trial between S and CSSS was performed (study II). Results: In study I, significant blood contamination was seen using S with 20 compared with 15 actuations (p = 0.002). Diagnostic yield of malignancy was not significantly different between 10, 15, and 20 actuations with S, whereas it was statistically higher for 15 actuations compared with 10 actuations with NS (p = 0.001). In study II, no difference was noted in diagnostic yield with 15 actuations between S and CSSS (88% vs. 90%, p = 0.74). Conclusions: Increasing actuation in NS resulted in a better diagnostic yield for EUS-FNA without significant blood contamination, whereas increasing actuation in S did not change the diagnostic yield of EUS-FNA while causing significant blood contamination. With 15 actuations, the diagnostic yield was comparable between S and CSSS.

[Clinical and Technical Guideline for Endoscopic Ultrasound-guided Tissue Acquisition of Pancreatic Solid Tumor: Korean Society of Gastrointestinal Endoscopy]

Endoscopic ultrasound (EUS)-guided tissue acquisition of pancreatic solid tumor requires a strict recommendation for its proper use in clinical practice because of its technical difficulty and invasiveness. The Korean Society of Gastrointestinal Endoscopy appointed a Task Force to draft clinical practice guidelines for EUS-guided tissue acquisition of pancreatic solid tumor. The strength of recommendation and the level of evidence for each statement were graded according to the Minds Handbook for Clinical Practice Guideline Development 2014. The committee, comprising a development panel of 16 endosonographers and an expert on guideline development methodology, developed 12 evidence-based recommendations in eight categories intended to help physicians make evidence- based clinical judgments with regard to the diagnosis of pancreatic solid tumor. This clinical practice guideline discusses EUS-guided sampling in pancreatic solid tumor and makes recommendations on circumstances that warrant its use, technical issues related to maximizing the diagnostic yield (e.g., needle type, needle diameter, adequate number of needle passes, sample obtaining techniques, and methods of specimen processing), adverse events of EUS-guided tissue acquisition, and learning-related issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This guideline may not be applicable for all clinical situations and should be interpreted in light of specific situations and the availability of resources. It will be revised as necessary to cover progress and changes in technology and evidence from clinical practice.

Wet- versus dry-suction techniques for EUS-FNA of solid lesions: A systematic review and meta-analysis

The optimal sampling techniques for EUS-FNA remain unclear and have not been standardized. To improve diagnostic accuracy, suction techniques for EUS-FNA have been developed and are widely used among endoscopists. The aim of this study was to compare wet-suction and dry-suction EUS-FNA techniques for sampling solid lesions. We performed a comprehensive literature search of major databases (from inception to June 2020) to identify prospective studies comparing wet-suction EUS-FNA and dry-suction EUS-FNA. Specimen adequacy, sample contamination, and histologic accuracy were assessed by pooling data using a random-effects model expressed in terms of odds ratio (OR) and 95% confidence interval (CI). Six studies including a total of 418 patients (365 wet suction vs. 377 dry suction) were included in our final analysis. The study included a total of 535 lesions (332 pancreatic lesions and 203 nonpancreatic lesions). The pooled odds of sample adequacy was 3.18 (CI: 1.82-5.54, P = 0.001) comparing wet- and dry-suction cohorts. The pooled odds of blood contamination was 1.18 (CI: 0.75-1.86, P = 0.1). The pooled rate for blood contamination was 58.33% (CI: 53.65%-62.90%) in the wet-suction cohort and 54.60% (CI 49.90%- 59.24%) in the dry-suction cohort (P = 0.256). The pooled odds of histological diagnosis was 3.68 (CI 0.82-16.42, P = 0.1). Very few adverse events were observed and did not have an impact on patient outcomes using either method. EUS-FNA using the wet-suction technique offers higher specimen quality through comparable rates of blood contamination and histological accuracy compared to dry-suction EUS-FNA.

Feasibility of BRCA1/2 Testing of Formalin-Fixed and Paraffin-Embedded Pancreatic Tumor Samples: A Consecutive Clinical Series

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer, with most patients diagnosed at advanced stages. First-line treatment based on a combined chemotherapy (FOLFIRINOX or gemcitabine plus nab-paclitaxel) provides limited benefits. Olaparib, a PARP inhibitor, has been approved as maintenance for PDAC patients harboring germline BRCA1/2 pathogenic mutations and previously treated with a platinum-based chemotherapy. BRCA1/2 germline testing is recommended, but also somatic mutations could predict responses to PARP inhibitors. Analysis of tumor tissues can detect both germline and somatic mutations and potential resistance alterations. Few data are available about BRCA1/2 testing on pancreatic tumor tissues, which often include limited biological material. We performed BRCA1/2 testing, by an amplicon-based Next Generation Sequencing (NGS) panel, on 37 consecutive PDAC clinical samples: 86.5% of cases were adequate for NGS analysis, with a success rate of 81.2% (median DNA input: 10 nanograms). Three BRCA2 mutations were detected (11.5%). Failed samples were all from tissue macrosections, which had higher fragmented DNA than standard sections, biopsies and fine-needle aspirations, likely due to fixation procedures. BRCA1/2 testing on pancreatic tumor tissues can also be feasible on small biopsies, but more cases must be analyzed to define its role and value in the PDAC diagnostic algorithm.

Comparison between modified wet suction and dry suction technique for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions

BACKGROUND AND AIM

Although endoscopic ultrasound-guided fine-needle biopsy is widely applied, there is no clear consensus on the optimal biopsy technique. We described a modified wet suction technique (MWEST) with the aim to compare the efficacy and safety between MWEST and the dry suction technique (DST).

METHODS

In this prospective, randomized, crossover, single-blinded study, patients with suspected pancreatic malignancy were randomized to the DST (group A) or MWEST (group B) for the first pass, and the two techniques were performed alternately. The primary outcome was the comparison of specimen adequacy and diagnostic yield between the techniques. Secondary outcomes included the macroscopic visible core length, blood contamination of specimens, and adverse events of both techniques.

RESULTS

From January 2019 to September 2019, 216 passes were performed in 50 patients. The specimen adequacy was significantly higher in "per-lesion" (P = 0.026), "per-pass" (cytology: P = 0.034; histology: P = 0.042), and first-pass analysis (P = 0.034) for MWEST than for DST. In diagnostic yield, MWEST showed significantly superior histological yield (P = 0.014) and first-pass analysis (κ: MWEST: 0.743 and DST: 0.519) compared with DST. The median macroscopic visible core lengths were 8 mm (interquartile range: 3.25-15 mm) and 10 mm (interquartile range: 5.25-15 mm) for DST and MWEST, respectively (P = 0.036). Blood contamination was significantly more serious in DST than in MWEST (cytology: P = 0.021; histology: P = 0.042).

CONCLUSIONS

Endoscopic ultrasound-guided fine-needle biopsy with MWEST resulted in significantly better quality of specimen, histological, and first-pass diagnostic yields and comparable safety compared with the DST. MWEST is preferred for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions.

Slow-pull capillary technique versus suction technique in endobronchial ultrasound-guided transbronchial needle aspiration for diagnosing diseases involving hilar and mediastinal lymph node enlargement

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a widely used, safe, and accurate technique for obtaining pathological specimens to be used in the diagnosis of diseases involving lung hilar and mediastinal lymph node (LN) enlargement. However, application of the suction technique during EBUS-TBNA remains controversial. In addition, the effectiveness of the slow-pull capillary technique for the diagnosis of pancreatic masses was recently reported. The aim of this study was to compare the diagnostic accuracy of EBUS-TBNA using these two techniques.

METHODS

The accuracy, sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and availability of tissue cores of the suction and slow-pull capillary techniques were studied retrospectively in patients who underwent EBUS-TBNA for the diagnosis of diseases involving lung hilar and mediastinal LN enlargement.

RESULTS

A total of 97 patients with hilar and mediastinal LN enlargement underwent EBUS-TBNA; 30 patients underwent the suction technique, 56 patients underwent the slow-pull capillary technique, 5 patients underwent both techniques, and 6 patients had failed operations. The accuracy, sensitivity, specificity, NPV, PPV, and the number of tissue cores obtained with the suction and slow-pull capillary techniques were 66.67% versus 85.71% (p = 0.039), 43.75% versus 85.42% (p < 0.001), 92.86% versus 87.5% (p > 0.05), 59.09% versus 50% (p > 0.05), 87.5% versus 97.62% (p > 0.05), and 19 versus 50 (p = 0.004), respectively. In both univariate and multivariate analyses, the acquisition of tissue core was significantly associated with the diagnostic accuracy of EBUS-TBNA. Moreover, the slow-pull capillary technique was significantly associated with the acquisition of tissue core in EBUS-TBNA. There were no significant differences between the two groups in the blood contamination of samples.

CONCLUSIONS

Use of the slow-pull capillary technique in EBUS-TBNA can significantly increase the accuracy related to the diagnosis of diseases involving hilar and mediastinal LN enlargement by improving the acquisition of tissue core. The reviews of this paper are available via the supplemental material section.

Comparative diagnostic accuracy of EUS needles in solid pancreatic masses: a network meta-analysis

Background and study aims  Endoscopic ultrasound (EUS)-guided tissue sampling is the standard of care for diagnosing solid pancreatic lesions. While many two-way comparisons between needle types have been made in randomized controlled trials (RCTs), it is unclear which size and type of needle offers the best probability of diagnosis. We therefore performed a network meta-analysis (NMA) to compare different sized and shaped needles to rank the diagnostic performance of each needle. Methods  We searched MEDLINE, EMBASE and Cochrane Library databases through August, 2020 for RCTs that compared the diagnostic accuracy of EUS fine-needle aspiration (FNA) and biopsy (FNB) needles in solid pancreatic masses. Using a random-effects NMA under the frequentist framework, RCTs were analyzed to identify the best needle type and sampling technique. Performance scores (P-scores) were used to rank the different needles based on pooled diagnostic accuracy. The NMA model was used to calculate pairwise relative risk (RR) with 95 % confidence intervals. Results  Review of 2577 studies yielded 29 RCTs for quantitative synthesis, comparing 13 different needle types. All 22G FNB needles had an RR > 1 compared to the reference 22G FNA (Cook) needle. The highest P-scores were seen with the 22G Medtronic FNB needle (0.9279), followed by the 22G Olympus FNB needle (0.8962) and the 22G Boston Scientific FNB needle (0.8739). Diagnostic accuracy was not significantly different between needles with or without suction. Conclusions  In comparison to FNA needles, FNB needles offer the highest diagnostic performance in sampling pancreatic masses, particularly with 22G FNB needles.

The Impact of Recent Advances in Endoscopic Ultrasound-Guided Tissue Acquisition on the Management of Pancreatic Cancer

Over the last few decades, endoscopic ultrasound (EUS)-guided tissue acquisition has become the method of choice for the pathological diagnosis of solid pancreatic lesions. Due to its high diagnostic yield and low complication rate, EUS-guided tissue acquisition has surpassed percutaneous sampling techniques. For many years, EUS-guided fine-needle aspiration (EUS-FNA) was traditionally used to obtain cytological aspirates of solid pancreatic lesions, with sensitivity values ranging from 80 to 90% for the diagnosis of malignancy. Nevertheless, despite numerous technical advances, EUS-FNA still presents some limitations. Therefore, EUS-guided fine-needle biopsy (EUS-FNB) has been introduced to provide tissue core biopsies, allowing histological assessment. A newly developed generation of FNB needles has demonstrated an outstanding diagnostic accuracy of over 95% for solid pancreatic lesions and provides samples appropriate for ancillary testing, such as immunohistochemistry and tumour molecular profiling. As a result, EUS-FNB is rapidly replacing EUS-FNA and is now the recommended technique for EUS-guided tissue acquisition in pancreatic cancer. Furthermore, with the recent expansion of neoadjuvant treatment criteria and with the advent of novel and personalised anti-cancer therapies, EUS-FNB is gaining a pivotal role in pancreatic cancer management and might soon be generalised to all patients, independent of disease stage. In this article, the authors present an updated review of the role of EUS-guided tissue acquisition in pancreatic cancer. Current indications, several technical aspects and new applications of EUS-FNA and EUS-FNB are discussed.

Clinical and Technical Guideline for Endoscopic Ultrasound (EUS)-Guided Tissue Acquisition of Pancreatic Solid Tumor: Korean Society of Gastrointestinal Endoscopy (KSGE)

Endoscopic ultrasound (EUS)-guided tissue acquisition of pancreatic solid tumor requires a strict recommendation for its proper use in clinical practice because of its technical difficulty and invasiveness. The Korean Society of Gastrointestinal Endoscopy (KSGE) appointed a task force to draft clinical practice guidelines for EUS-guided tissue acquisition of pancreatic solid tumor. The strength of recommendation and the level of evidence for each statement were graded according to the Minds Handbook for Clinical Practice Guideline Development 2014. The committee, comprising a development panel of 16 endosonographers and an expert on guideline development methodology, developed 12 evidence-based recommendations in eight categories intended to help physicians make evidence-based clinical judgments with regard to the diagnosis of pancreatic solid tumor. This clinical practice guideline discusses EUS-guided sampling in pancreatic solid tumor and makes recommendations on circumstances that warrant its use, technical issues related to maximizing the diagnostic yield (e.g., needle type, needle diameter, adequate number of needle passes, sample obtaining techniques, and methods of specimen processing), adverse events of EUS-guided tissue acquisition, and learning-related issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This guideline may not be applicable for all clinical situations and should be interpreted in light of specific situations and the availability of resources. It will be revised as necessary to cover progress and changes in technology and evidence from clinical practice. (Gut Liver 2021;15:-374)

Intermittent endoscopic ultrasound guided fine-needle aspiration for the diagnosis of solid pancreatic lesions. Pilot study

Background and purpose of the study: endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) is the method of choice for sampling pancreatic solid lesions. However, there is significant heterogeneity in terms of the technique used. Intermittent aspiration has not been evaluated in pancreatic solid lesions and could improve the diagnostic performance.

METHODS

Single-blind, non-inferiority pilot study. Patients with solid pancreatic lesions and indication for EUS-FNA were prospectively included. Patients were randomly assigned to intermittent (IS) or continuous (CS) suction techniques. Diagnostic performance, cellularity, blood contamination and number of passes required to reach diagnosis were evaluated.

MAIN RESULTS

33 patients were assigned to CS (16 patients) or IS (17 patients). Diagnostic performance was 87.5% for CS and 94.1% for IS (OR 2.29, 95%CI 0.19-27.99, p = 0.51). In the IS group samples had higher cellularity (OR 1.83, 95%CI 0.48-6.91, p = 0.37) and lower blood contamination (OR 0.38, 95%CI 0.09-1.54, p = 0.18). The number of passes required to reach diagnosis was 2.12 for CS and 1.94 for IS (p = 0.64). Liquid cytology was obtained in 73.3% of IS and 61.5% of CS (OR 1.72, 95%CI 0.35-8.50).

CONCLUSIONS

The IS technique was not inferior to CS in terms of diagnostic accuracy in the evaluation of pancreatic solid lesions, with a tendency to obtain higher cellularity, lower blood contamination and frequent presence of cell block.

Factors of Endoscopic Ultrasound-Guided Tissue Acquisition for Successful Next-Generation Sequencing in Pancreatic Ductal Adenocarcinoma

Background/Aims

Recent advances in understanding the genetics of pancreatic ductal adenocarcinoma (PDAC) have led to the potential for a personalized approach. Several studies have described the feasibility of generating genetic profiles of PDAC with next-generation sequencing (NGS) of samples obtained through endoscopic ultrasound-guided tissue acquisition (EUS-TA). The aim of this study was to find the best EUS-TA approach for successful NGS of PDAC.

Methods

We attempted to perform NGS with tissues from 190 patients with histologically proven PDAC by endoscopic ultrasound-guided fine-needle aspiration and endoscopic ultrasound-guided fine-needle biopsy at Samsung Medical Center between November 2011 and February 2015. The medical records of these patients were retrospectively reviewed for parameters including tumor factors (size, location, and T stage), EUS-TA factors (needle gauge [G], needle type, and number of needle passes) and histologic factors (cellularity and blood contamination). The sample used for NGS was part of the EUS-TA specimen that underwent cytological and histological analysis.

Results

NGS could be successfully performed in 109 patients (57.4%). In the univariate analysis, a large needle G (p=0.003) and tumor located in the body/tail (p=0.005) were associated with successful NGS. The multivariate logistic regression analysis revealed that the needle G was an independent factor of successful NGS (odds ratio, 2.19; 95% confidence interval, 1.08 to 4.47; p=0.031).

Conclusions

The needle G is an independent factor associated with successful NGS. This finding may suggest that the quantity of cells obtained from EUS-TA specimens is important for successful NGS.

Does ProCore Fine-Needle Biopsy Really Improve the Clinical Outcome of Endoscopic Ultrasound-Guided Sampling of Pancreatic Masses?

INTRODUCTION

Fine-needle biopsy (FNB) has been suggested to provide better histological samples as compared to endoscopic ultrasound fine-needle aspiration (EUS-FNA). However, studies comparing EUS-FNA and EUS-FNB for pancreatic lesions reported contrasting results. The aim of this study was to compare the clinical performance of EUS-FNA versus EUS-FNB with the ProCore needle for the investigation of pancreatic lesions.

METHODS

We reviewed all patients undergoing EUS for the investigation of pancreatic lesions from August 2012 to September 2018. From August 2012 to January 2015, all procedures were performed with standard needles, whereas from February 2015 to September 2018, the use of ProCore needles had been introduced. Data on diagnostic accuracy, number of needle passes, and/or adverse events were collected.

RESULTS

Three hundred twenty-four patients were retrospectively evaluated: 190 (58.6%) underwent EUS-FNA and 134 (41.4%) EUS-FNB. Both EUS-FNA and EUS-FNB showed high diagnostic accuracy for malignancy (94% [95% CI: 89-97%] vs. 94% [95% CI: 89-98%]). Notably, there were no differences between EUS-FNA and EUS-FNB in terms of sensitivity, specificity, positive and negative likelihood ratio, histological core tissue retrieval, adverse events, or number of needle passes. However, subgroup analysis noted a higher diagnostic accuracy for 25G EUS-FNB as compared to 25G EUS-FNA (85.7 vs. 55.5%; *p = 0.023).

CONCLUSION

EUS-FNB with the ProCore needle is safe and feasible in pancreatic lesions. The ProCore needle did not provide any advantage in terms of diagnostic accuracy, sensitivity, specificity, positive and/or negative likelihood ratio, or acquisition of the core specimen; therefore, its routine application is not supported.

Clinical and Technical Guideline for Endoscopic Ultrasound (EUS)-Guided Tissue Acquisition of Pancreatic Solid Tumor: Korean Society of Gastrointestinal Endoscopy (KSGE)

Endoscopic ultrasound (EUS)-guided tissue acquisition of pancreatic solid tumor requires a strict recommendation for its proper use in clinical practice because of its technical difficulty and invasiveness. The Korean Society of Gastrointestinal Endoscopy (KSGE) appointed a Task Force to draft clinical practice guidelines for EUS-guided tissue acquisition of pancreatic solid tumor. The strength of recommendation and the level of evidence for each statement were graded according to the Minds Handbook for Clinical Practice Guideline Development 2014. The committee, comprising a development panel of 16 endosonographers and an expert on guideline development methodology, developed 12 evidence-based recommendations in 8 categories intended to help physicians make evidence-based clinical judgments with regard to the diagnosis of pancreatic solid tumor. This clinical practice guideline discusses EUS-guided sampling in pancreatic solid tumor and makes recommendations on circumstances that warrant its use, technical issues related to maximizing the diagnostic yield (e.g., needle type, needle diameter, adequate number of needle passes, sample obtaining techniques, and methods of specimen processing), adverse events of EUS-guided tissue acquisition, and learning-related issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This guideline may not be applicable for all clinical situations and should be interpreted in light of specific situations and the availability of resources. It will be revised as necessary to cover progress and changes in technology and evidence from clinical practice.

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

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

Stylet Slow-pull Versus Standard Suction for Endoscopic Ultrasound-guided Fine-needle Aspiration/Biopsy of Pancreatic Solid Masses: A Meta-Analysis

BACKGROUND AND STUDY AIM

There is limited evidence on the diagnostic performance of the stylet slow-pull (SP) method for endoscopic ultrasound-guided fine-needle aspiration/biopsy. The aim of this study was to compare the SP method with standard suction (SS) for endoscopic ultrasound-guided fine-needle aspiration/biopsy of solid pancreatic masses.

METHODS

A computerized bibliographic search of the main databases, including PubMed, EMBASE, Cochrane Library, and Science Citation Index, was performed through February 2020. The main outcome measurements were diagnostic accuracy, cellularity, low blood contamination, adequate core tissue acquisition, and technical success rate.

RESULTS

Eleven studies (including 6 randomized trials) were included, with a total of 504 patients who underwent SP and 551 who underwent SS. Diagnostic accuracy was significantly superior in the SP group, compared with the SS group [odds ratio (OR)=1.60; 95% confidence interval (CI), 1.14-2.26]. The SP group had higher pooled rates of low blood contamination (OR=1.93; 95% CI, 1.29-2.87) and adequate core tissue acquisition (OR=1.91; 95% CI, 1.11-3.26) than the SS group. There was no significant difference between groups in the adequacy of cellularity (OR=0.99; 95% CI, 0.63-1.57; P=0.98) or technical success rate (OR=0.38; 95% CI, 0.13-1.15; P=0.09).

CONCLUSIONS

The authors provide evidence that SP is superior to SS in diagnostic accuracy, low blood contamination, and adequate core tissue acquisition, without reducing adequacy of cellularity or technical success rate.

IS THE NEW PROCORE 20G DOUBLE FORWARD-BEVEL NEEDLE CAPABLE TO OBTAIN BETTER HISTOLOGICAL SAMPLES BY ENDOSCOPIC ULTRASOUND FOR DIAGNOSING SOLID PANCREATIC LESIONS?

BACKGROUND

Fine needle biopsy (FNB) histological samples by endoscopic ultrasound. It is important to obtain representative histological samples of solid biliopancreatic lesions without a clear indication for resection. The role of new needles in such task is yet to be determined.

AIM

To compare performance assessment between 20G double fine needle biopsy (FNB) and conventional 22G fine needle aspiration (FNA) needles for endoscopic ultrasound (EUS)-guided biopsy.

METHODS

This prospective study examined 20 patients who underwent the random puncture of solid pancreatic lesions with both needles and the analysis of tissue samples by a single pathologist.

RESULTS

The ProCore 20G FNB needle provided more adequate tissue samples (16 vs. 9, p=0.039) with better cellularity quantitative scores (11 vs. 5, p=0.002) and larger diameter of the histological sample (1.51±1.3 mm vs. 0.94±0.55 mm, p=0.032) than the 22G needle. The technical success, puncture difficulty, and sample bleeding were similar between groups. The sensitivity, specificity, and diagnostic accuracy were 88.9%, 100%, and 90% and 77.8%, 100%, and 78.9% for the 20G and 22G needles, respectively.

CONCLUSIONS

The samples obtained with the ProCore 20G FNB showed better histological parameters; although there was no difference in the diagnostic performance between the two needles, these findings may improve pathologist performance.

Optimal number of needle passes during EUS-guided fine-needle biopsy of solid pancreatic lesions with 22G ProCore needles and different suction techniques: A randomized controlled trial

Background and Objectives:

The sensitivity of EUS-guided fine-needle biopsy (EUS-FNB) varies considerably. The optimal number of passes through a solid pancreatic lesion with a 22G FNB needle during EUS-FNB is controversial. This prospective randomized controlled study aimed to determine the optimal number of needle passes during EUS-FNB of solid pancreatic lesions, with 22G FNB needles and different sampling techniques.

Methods:

Pancreatic masses were sampled using 22G FNB needles with either the stylet slow-pull (SP) technique or the standard-suction (SS) technique. We determined the number of needle passes required to obtain a diagnostic accuracy of >90%. Differences between the two techniques in terms of technical success rate, cytological acquisition, core tissue acquisition, sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and complications were analyzed.

Results:

A total of 120 patients were randomly assigned to either SP or SS group. Three patients who were lost to follow-up and one who did not complete 5 passes due to bent needle head were excluded from the study. Fifty-six cases in the SP group and 60 cases in the SS group were included in the analysis. For SP technique, the cumulative accuracy of passes 1, 2, 3, 4, and 5 was 44.83%, 76.79%, 87.50%, 92.86%, and 94.64%, respectively. For SS technique, the cumulative accuracy of passes 1, 2, 3, 4, and 5 was 71.67%, 85.0%, 90.0%, 93.33%, and 95.0%, respectively. For each group, there was no statistically significant difference in accuracy after 3 and 4 passes. After 4 passes, the pooled sensitivity (92.59% vs. 93.10%), accuracy (92.86% vs. 93.10%), and specificity (100% vs. 100%) were similar (P > 0.05) in the SP and SS groups, respectively. In addition, positive cytological diagnoses (83.9% vs. 85.0%) and positive histological diagnoses (71.4% vs. 78.3%) were comparable (P > 0.05) in the SP and SS groups, respectively. No statistically significant factor was found associated with diagnostic sensitivity for each group.

Conclusion:

When on-site cytological evaluation is unavailable, we recommend that at least 3 passes with 22G ProCore needles be performed during EUS-FNB using the SS technique, at least 4 passes when using SP technique. The SS technique showed potential advantages over SP technique in tissue acquisition and diagnostic capabilities.

Wet- versus dry-suction techniques for endoscopic ultrasound-guided fine-needle aspiration of solid lesions: a multicenter randomized controlled trial

BACKGROUND

The optimal sampling techniques for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) remain unclear and have not been standardized. The aim of this study was to compare the wet-suction and dry-suction techniques for sampling solid lesions in the pancreas, mediastinum, and abdomen.

METHODS

This was a multicenter, crossover, randomized controlled trial with randomized order of sampling techniques. The 296 consecutive patients underwent EUS-FNA with 22G needles and were randomized in a ratio of 1:1 into two separate groups that received the dry-suction and wet-suction techniques in a different order. The primary outcome was to compare the histological diagnostic accuracy of dry suction and wet suction for malignancy. The secondary outcomes were to compare the cytological diagnostic accuracy and specimen quality.

RESULTS

Among the 269 patients with pancreatic (n = 161) and non-pancreatic (n = 108) lesions analyzed, the wet-suction technique had a significantly better histological diagnostic accuracy (84.9 % [95 % confidence interval (CI) 79.9 % - 89.0 %] vs. 73.2 % [95 %CI 67.1 % - 78.7 %]; P = 0.001), higher specimen adequacy (94.8 % vs. 78.8 %; P < 0.001), and less blood contamination (P < 0.001) than the dry-suction technique. In addition, sampling non-pancreatic lesions with two passes of wet suction provided a histological diagnostic accuracy of 91.6 %.

CONCLUSIONS

The wet-suction technique in EUS-FNA generates better histological diagnostic accuracy and specimen quality than the dry-suction technique. Furthermore, sampling non-pancreatic lesions with two passes of EUS-FNA with wet suction may provide a definitive histological diagnosis when rapid on-site evaluation is not routinely available.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration (EUS-FNA) with Image Enhancement

Although endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is useful in the differential diagnosis of solid pancreatic lesions, lymph nodes, and liver lesions, inadequate sampling may result in an incorrect pathological diagnosis. The accuracy of EUS for the evaluation of pancreatobiliary lesions may be increased by image enhancement technologies, including contrast-enhanced harmonic (CH)-EUS and EUS-elastography. These methods can provide information that complement EUS-FNA for the diagnosis and staging of pancreatobiliary cancer, and can help to identify the EUS-FNA target, reducing the requirement for repeat FNA.

The safety and efficacy of endoscopic ultrasound-guided ablation therapy for solid pancreatic tumors: a systematic review

BACKGROUND AND AIMS

Recently, endoscopic ultrasound (EUS)-guided ablation therapy, as a minimally invasive technique, has shown its potential to substitute surgery in treating solid pancreatic tumors, such as small potential malignant pancreatic tumors, small insulinomas and locally advanced pancreatic ductal adenocarcinoma (LAPDAC). Therefore, we conducted this systematic review to assess the safety and efficacy of EUS-guided ablation therapy for solid pancreatic tumors.

METHODS

We conducted a comprehensive search of PubMed, Embase, Cochrane library and Web of Science databases from inception to February 2020. The endpoints were clinical success and complications rates. The pooled event rate was calculated using Comprehensive Meta Analysis software.

RESULTS

Fourteen studies with a total of 158 patients were included in our final analysis. The major types of solid pancreatic tumors were nonfunction pancreatic neuroendocrine tumors (n = 78, 49.4%), LAPDAC (n = 48, 30.4%) and insulinomas (n = 26, 16.5%). Overall, the pooled clinical success rate was 85.9% (95% confidence interval (CI): 75.4-92.4%, I ² = 25.18%), pooled complications rate was 29.1% (95% CI: 18.6-42.3%, I ² = 50.40%). Subgroup analysis was performed based on ablation methods, which showed clinical success rate for radiofrequency ablation (RFA) was 83.5% (95% CI: 67.9-92.4%), and 87.9% (95% CI: 66.2-96.4%) for ethanol ablation (EA). In terms of complications rate, it was 32.2% (95% CI: 19.4-48.4%) for RFA, and 21.2% (95% CI: 6.8-49.9%) for EA.

CONCLUSIONS

EUS-guided ablation therapy is a promising alternative treatment for solid pancreatic tumors, especially for p-NETs and insulinomas < 2 cm, with rarely severe complications. Further prospective studies with long-term follow-up are warranted in future.

Diagnostic efficacy of three suction techniques for endoscopic ultrasound-guided fine-needle biopsy of solid pancreatic lesions: protocol for a multicenter randomized cross-over clinical trial

BACKGROUND

How suction technique affects endoscopic ultrasound-guided tissue acquisition (EUS-TA) remains unclear. A standardized protocol is currently lacking, with most previous studies being restricted to EUS-guided fine-needle aspiration (EUS-FNA). The research related to EUS-guided fine-needle biopsy (EUS-FNB) is sparse.

AIMS

The aim of this study is to evaluate the diagnostic efficacy, cellularity, tissue acquisition, blood contamination and adverse event rate of three common suction techniques (standard suction, slow-pull, and wet suction) used for EUS-FNB of solid pancreatic masses.

METHODS

This is a multicenter single-blind randomized cross-over superiority trial. A total of 300 patients with suspected pancreatic malignancy will be enrolled from digestive endoscopic centers at five large tertiary hospitals in China. All three suction techniques will be performed on each patient using a 25G ProCore needle, with the sequence of suction techniques determined by randomization. Cytological and histological specimens obtained with each of the three techniques will be assessed independently. Outcomes among the three suction techniques will be compared.

DISCUSSION

To the best of our knowledge, this is the largest multicenter randomized cross-over trial designed to determine the optimal suction technique for the diagnosis of solid pancreatic masses. This study may contribute to standardizing the suction technique for EUS-FNB.

Suction versus slow-pull for endoscopic ultrasound-guided fine-needle aspiration of pancreatic tumors: a prospective randomized trial

BACKGROUND

Suction (S) is commonly used to improve cell acquisition during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Slow-pull (SP) sampling is another technique that might procure good quality specimens with less bloodiness. We aimed to determine if SP improves the diagnostic yield of EUS-FNA of pancreatic masses.

METHODS

Patients with pancreatic solid masses were randomized to four needle passes with both techniques in an alternate fashion. Sensitivity, specificity, positive, and negative predictive values were calculated. Cellularity and bloodiness of cytological samples were assessed and compared according to the technique.

RESULTS

Sensitivity, specificity, and accuracy of suction vs. SP were 95.2% vs. 92.3%; 100% vs. 100; 95.7% vs. 93%, respectively. As to the association of methods, they were 95.6, 100 and 96%, respectively. Positive predictive values for S and SP were 100%. There was no difference in diagnostic yield between S and SP (p = 0.344). Cellularity of samples obtained with SP and Suction were equivalent in both smear evaluation (p = 0.119) and cell-block (0.980). Bloodiness of SP and suction techniques were similar as well.

CONCLUSIONS

S and SP techniques provide equivalent sensitivity, specificity, and accuracy. Association of methods seems to improve diagnostic yield. Suction does not increase the bloodiness of samples compared to slow-pull.

Slow-pull compared to suction technique for EUS-guided sampling of pancreatic solid lesions: a meta-analysis of randomized controlled trials

Background and study aims  Current ESGE guidelines suggest employing the suction (SU) technique for endoscopic ultrasound (EUS)-guided sampling of pancreatic solid lesions. Nonetheless, recent randomized controlled trials (RCT) have reported that the slow-pull (SP) technique has similar diagnostic accuracy with possibly less blood contamination. However, these results are heterogeneous and limited to small cohorts. The aim of this meta-analysis was to compare adequacy, accuracy, sensitivity and specificity of the SU and SP techniques for EUS-guided sampling of solid pancreatic lesions. Methods  A computerized bibliographic search was restricted to RCTs. Pooled effects were calculated using a random-effects model and expressed in terms of pooled sensitivity and specificity and OR (95 % CI) for adequacy and accuracy. Results  Overall, seven RCTs were included, for a total of 475 patients (163 lesions sampled with SU, 164 with SP and 148 by both). The adequacy was similar (OR = 0.98) without heterogeneity (I 2  = 0 %), but a high degree of blood contamination was more common with SU than SP (pooled rate 27.6 % vs 19.7 %). A non-significant superiority of SP in terms of pooled accuracy (OR = 0.82; 95 % CI 0.36-1.85) was recorded, with moderate heterogeneity (I 2  = 52.4 %). The SP technique showed a slightly higher pooled sensitivity compared to SU (88.7 % vs 83.4 %), while specificity was similar (97.2 % SP vs 96.9 % SU), with considerable heterogeneity. Conclusion  The current meta-analysis reveals non-superiority of SU over SP, while SP results in reduced blood contamination. If the 5 % accuracy difference favouring SP is true, with alfa error = 0.05 and beta = 0.20, a RCT of 982 patients per arm is needed to confirm significance.

Endoscopic ultrasound-guided tissue sampling of pancreatic lesions

Important advancements in endoscopic ultrasound-guided tissue sampling techniques and development of new needle designs have improved the diagnostic yield of pancreatic lesions. This innovation in endoscopic ultrasound has also opened the door for early diagnosis and precision therapy in the management of cancer patients. Endoscopic ultrasound fine needle biopsy is an invaluable tool and newer biopsy designs will probably play a pivotal role in the management of pancreatic lesions in the next future. Aim of the current review was to provide an overview on the available techniques and devices for the endoscopic ultrasound-guided sampling of pancreatic solid and cystic lesions.

An international, multi-institution survey on performing EUS-FNA and fine needle biopsy

Background and Objectives

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and fine needle biopsy (FNB) are effective techniques that are widely used for tissue acquisition. However, it remains unclear how to obtain high-quality specimens. Therefore, we conducted a survey of EUS-FNA and FNB techniques to determine practice patterns worldwide and to develop strong recommendations based on the experience of experts in the field.

Methods

This was a worldwide multi-institutional survey among members of the International Society of EUS Task Force (ISEUS-TF). The survey was administered by E-mail through the SurveyMonkey website. In some cases, percentage agreement with some statements was calculated; in others, the options with the greatest numbers of responses were summarized. Another questionnaire about the level of recommendation was designed to assess the respondents' answers.

Results

ISEUS-TF members developed a questionnaire containing 17 questions that was sent to 53 experts. Thirty-five experts completed the survey within the specified period. Among them, 40% and 54.3% performed 50-200 and more than 200 EUS sampling procedures annually, respectively. Some practice patterns regarding FNA/FNB were recommended.

Conclusion

This is the first worldwide survey of EUS-FNA and FNB practice patterns. The results showed wide variations in practice patterns. Randomized studies are urgently needed to establish the best approach for optimizing the FNA/FNB procedures.

Safety and efficacy of endoscopic ultrasound-guided fine needle aspiration for pancreatic masses: A prospective multicenter study

OBJECTIVES

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for solid pancreatic lesions has high diagnostic yield. However, few prospective multicenter studies have been performed. We performed a prospective cohort study to evaluate the efficacy and safety of EUS-FNA for diagnosis of solid pancreatic lesions.

METHODS

This prospective cohort study involved five hospitals in Japan. The primary outcome was sensitivity of EUS-FNA for diagnosing malignant lesions. We also evaluated parameters of diagnostic sufficiency and the safety of EUS-FNA.

RESULTS

In total, 246 patients were enrolled. The absolute values of the parameters evaluated showed no significant differences; however, the percentage changes in the white blood cell counts and C-reactive protein levels after examination were significantly higher, and the percentage change in hemoglobin concentrations was significantly lower. The minor and major complication rates at the time of puncture, 24 h, 7 days and 28 days were 4.1%, 2.8%, 1.6%, and 0.0%, respectively. The true complication rate was 1.2%. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 97.2%, 88.0%, 96.2%, 100%, and 81.4%, respectively.

CONCLUSIONS

EUS-FNA for solid pancreatic lesions has high diagnostic yield and is safe, consistent with previously studies.

EUS tissue acquisition: From A to B

EUS-guided tissue acquisition (EUS-TA) has made rapid development since its introduction in the early 1990s. The technique is widely accepted and invaluable for staging and diagnosis of a variety of upper gastrointestinal and mediastinal lesions. Fine-needle aspiration (FNA) has long been the gold standard, but due to its limitations such as the inability to retain stroma and associated cellular architecture, novel biopsy needles (FNB) were designed. Overall, FNA and FNB needles perform seemingly equally in terms of diagnostic accuracy, however, the second-generation FNB needles require less passes. The third-generation FNB needles (crown-cut needle types) seem to be preferable to FNA needles as well as to the second-generation FNB needles, when larger histological specimens and preserved tissue architecture are required. EUS-TA is constantly under development, and new applications of this technique include tumor risk stratification according to its genetic profile as well as minimally invasive creation of patient-derived organoids, hallmarks of personized medicine. It remains yet to be shown, whether these applications will lead to a decisive shift from aspiration to biopsy, i.e., from A to B.

Present and Future of Endoscopic Ultrasound-Guided Tissue Acquisition in Solid Pancreatic Tumors

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is a well-established method for pathological diagnosis of solid pancreatic neoplasm. It can be performed either as EUS-guided fine-needle aspiration (EUS-FNA) or EUS-guided fine-needle biopsy (EUSFNB). The incidence of adverse events related to EUS-TA is less than 1%. The factors that affect the diagnostic accuracy and specimen adequacy include the techniques used, type and size of the needle, competency of endosonographers, presence of cytopathologists/ cytotechnologists, and rapid on-site examination. EUS-TA may contribute to precision medicine through obtaining tissue samples for next-generation sequencing. The current status, several clinical issues for diagnostic yield and adverse events, and future perspectives of EUS-FNA/FNB for diagnosing pancreatic neoplasm have been discussed in this review article.

Endoscopic Ultrasound-Guided Fine Needle Aspiration and Biopsy in Gastrointestinal Subepithelial Tumors

The incidence of asymptomatic and incidentally found upper gastrointestinal subepithelial tumors (SETs) is increasing with the implementation of national cancer screening and the development of high-resolution endoscopy in Korea. However, endoscopy alone cannot be used to determine whether SETs are benign or malignant. Endoscopic ultrasound (EUS) is used to further characterize these lesions through the examination of their layered structure, internal echogenicity, size, and relationship to the extramural structure. These provide additional information on whether the lesion is benign or malignant. Nevertheless, the sensitivity and specificity of EUS alone in predicting malignancy is unsatisfactory. Recent guidelines have recommended deciding the timing of EUS-fine needle aspiration and biopsy (EUS-FNA/B) for SETs based on tumor size, malignant features on endoscopy, and high-risk features on EUS. The diagnostic accuracy of EUS-FNA/B is reportedly influenced by factors including needle size, number of needle passes, use of suction, use of a stylet in the needle assembly, fanning technique, availability of an on-site cytopathologist, and experience of the endosonographer. Therefore, according to the characteristics of the SETs, various subsequent methods and techniques should be appropriately employed to improve the diagnostic yield of EUS-FNA/B.

Endoscopic ultrasonography in pancreatic diseases: advances in tissue acquisition

Background and study aims  Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) improved the diagnostic performance and upgraded the role of endoscopic ultrasonography (EUS) into an interventional modality, able to guide patient management and treatment.This review aimed to highlight the advances, emerging practices, procedural techniques and technological innovations in EUS tissue acquisition in pancreatic diseases. Methods  A thorough review of the literature was performed using PubMed to identify articles that describe techniques, advances, and practices in EUS tissue acquisition in gastrointestinal diseases. Conclusion  Since the first EUS-FNA procedure, EUS guided-tissue acquisition has been evolving continuously. Development of needles with innovative tip design enabled procurement of larger samples with preserved histological architecture. Moreover, sampling techniques and complementary methods, such as contrast harmonic imaging and EUS-elastography, have been introduced in an effort to improve diagnostic performance and sample adequacy.

Collaboration of community hospital endosonographers improves diagnostic yield of endoscopic ultrasonography guided tissue acquisition of solid pancreatic lesions

Background and study aims  Endoscopic ultrasound (EUS)-guided tissue acquisition (TA) is the method of choice for establishing a pathological diagnosis of solid pancreatic lesions. Data on quality and yield of EUS-guided TA performed in community hospitals are lacking. A study was performed to determine and improve the diagnostic yield of EUS-guided TA in a group of community hospitals. Methods  Following analysis of the last 20 EUS-guided TA procedures of solid pancreatic lesions performed in each of four community hospitals, a collaborative EUS interest group was formed and a prospective registry was started. During meetings of the interest group, feedback on results per center were provided and strategies for improvement were discussed. Results  In the BEFORE team formation cohort, 80 procedures were performed in 66 patients. In the AFTER team formation cohort, 133 procedures were performed in 125 patients. After team formation, the rate of adequate sample increased from 80 % (95 %CI [0.7 - 0.9]) to 95 % (95 %CI [0.9 - 1.0]) , diagnostic yield of malignancy improved from 28 % (95 %CI [0.2 - 0.4]) to 64 % (95 % CI [0.6 - 0.7]), and sensitivity of malignancy improved from 63 % (95 %CI [0.4 - 0.8]) to 84 % (95 %CI [0.8 - 0.9]). Multivariate regression analysis revealed team formation to be the only variable significantly associated with an increased rate of adequate sample. Conclusions  Formation of a regional EUS interest group with regular feedback on results per center, and discussions on methods and techniques used, significantly improved the outcome of EUS-guided TA procedures in patients with solid pancreatic lesions in community hospitals.

Efficacy of 3 fine-needle biopsy techniques for suspected pancreatic malignancies in the absence of an on-site cytopathologist

BACKGROUND AND AIMS

EUS-guided fine-needle aspiration/biopsy (EUS-FNA/B) has a high diagnostic accuracy for pancreatic tumors. Most reports have focused on the diagnostic yield of cytology or histology; the ability of various FNA/B techniques to obtain an adequate mass of cells or tissue has rarely been investigated.

METHODS

Patients with suspected pancreatic malignancy underwent EUS-FNB using a 22-gauge ProCore needle by either the stylet slow-pull-back technique (group A), conventional negative suction after stylet removal (group B), or non-suction after stylet removal (group C) in the absence of an on-site cytopathologist. The adequacy of the 3 techniques based on the diagnostic yield, cellularity, blood contamination, and core-tissue acquisition was evaluated.

RESULTS

A total of 50 patients (27 males) were analyzed. The mean tumor size was 21 to 40 mm in 54%. The rate of a good or excellent proportion of cellularity was highest in group A compared with groups B and C (72% vs 60% vs 50%, P = .049). A >25% rate of blood contamination was more prevalent in group B (30% vs 42% vs 10%, P = .009). The rate of adequate core-tissue acquisition was not different (52% vs 34% vs 50%, P = .140). Based on the multivariate generalized estimation equation, the stylet slow-pull-back technique and a tumor size >40 mm were favorable factors for diagnostic adequacy.

CONCLUSIONS

The stylet slow-pull-back technique might enable acquisition of tissue and assessment of cellularity for the diagnosis of pancreatic tumors suspected to be malignant. (Clinical trial registration number: KCT0002190.).

Diagnostic Endoscopic Ultrasound: Technique, Current Status and Future Directions

Endoscopic ultrasound (EUS) is now well established as an important tool in clinical practice. From purely diagnostic imaging, it has progressed to include tissue acquisition, which provided the basis for therapeutic procedures. Even as interventional EUS developed, there has been ongoing progress in EUS diagnostic capabilities due to improved imaging systems, better needles for tissue acquisition and development of enhanced imaging functions such as contrast harmonic EUS (CHEUS) and EUS elastography. EUS is well established for differentiation of subepithelial lesions, for T-staging of luminal gastrointestinal and pancreaticobiliary malignancies, for differentiation of benign pancreaticobiliary disorders and for diagnostic tissue acquisition, which can be achieved by EUS-guided fine needle aspiration or by EUS-guided fine needle biopsy using dedicated biopsy needles. This review briefly describes the technique of performing EUS and then discusses its clinical utility in terms of gastrointestinal cancer staging, the evaluation of pancreaticobiliary disorders and tissue acquisition. Enhanced imaging techniques such as CHEUS and EUS elastography are briefly reviewed.

Prospective comparison of slow-pull and standard suction techniques of endoscopic ultrasound-guided fine needle aspiration in the diagnosis of solid pancreatic cancer

Background

The usage of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for the diagnosis of solid pancreatic cancer is increasing, however mainly retrospective studies are available about the detailed methods of sampling.

Methods

To compare prospectively the diagnostic yield of EUS-FNA samples obtained with slow-pull (SP) and with standard suction technique (SS).

Results

EUS-FNA sampling was diagnostic in 72 of 92 cases (78.3%). Diagnostic yield was 67.4% in the SS and 65.2% in the SP group. The number of smear pairs (1.84 vs. 3.56; p < 0.001) and blood contamination (1.50 vs. 2.19; p < 0.001) were significantly higher in the SS group, which resulted in lower rate of diagnostic samples (41.8% vs. 30.0%; p = 0.003). There was no difference in the cellularity (1.58 vs. 1.37; p = 0.2554), or in the sensitivity and specificity in the identification of malignancy between SP and SS subgroups (69.9, 100% vs. 73.5, 100%). Histological samples were obtained in 60 cases (with SP: 49 cases; with SS: 46 cases). There was no difference in the diagnostic yield of histological samples between the groups (63 and 58.7%).

Conclusion

The diagnostic yield, the cellularity of smears and the rate of acquiring sufficient histological material are similar in the SP and SS group, but due to lower bloodiness and decreased number of slides, the pathological diagnosis is faster and more cost-effective.

Endoscopic Ultrasound-Guided Tissue Acquisition: Techniques and Challenges

Endoscopic ultrasound-guided fine needle aspiration (EUS FNA) has made pathological diagnosis of pancreatic neoplasms, diseases involving lymph nodes at various mediastinal and abdominal sites, gastrointestinal submucosal lesions, perirectal lesions, adrenal lesions, and mediastinal masses easy. EUS-guided FNA is a multistep procedure that involves assessment of proper clinical indication, correct selection of FNA needles, and adoption of evidence-based techniques for tissue sampling. EUS FNA is done by needles that are available in different sizes, mainly 25, 22, and 19-gauge needle. The need of onsite cytopathologist, dependence on histology/core biopsy occasionally to get a diagnosis, and inability to reliably assess for molecular markers are important limitations of EUS FNA. EUS-guided fine needle biopsy (FNB) that samples the core of tissue is an exciting new development in the field of diagnostic EUS. FNB needles are expensive than FNA needles, and although the initial results are encouraging, more studies with robust evidence proving their superiority beyond any doubt are needed before they can be widely used.

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

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

Recent advancement in EUS-guided fine needle sampling

EUS-guided tissue acquisition technique plays an essential role for evaluation of gastrointestinal tumors. Several components affect the yield of EUS-guided tissue acquisition outcomes such as sampling techniques, use of ROSE (rapid onsite evaluation), training and experience, and needle designs. In this review we discuss advancement in EUS-guided fine needle sampling.