Endoscopic ultrasound-guided tissue acquisition with or without macroscopic on-site evaluation: randomized controlled trial

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.

Consensus statements on endoscopic ultrasound-guided tissue acquisition. Guidelines from the Asian Endoscopic Ultrasound Group

OBJECTIVES

This consensus was developed by the Asian EUS Group (AEG), who aimed to formulate a set of practice guidelines addressing various aspects of endoscopic ultrasound-guided tissue acquisition (EUS-TA).

METHODS

The AEG initiated the development of consensus statements and formed an expert panel comprising surgeons, gastroenterologists, and pathologists. Three online consensus meetings were conducted to consolidate the statements and votes. The statements were presented and discussed in the first two consensus meetings and revised according to comments. Final voting was conducted at a third consensus meeting. The Grading of Recommendations, Assessment, Development, and Evaluation system was adopted to define the strength of the recommendations and quality of evidence.

RESULTS

A total of 20 clinical questions and statements regarding EUS-TA were formulated. The committee recommended that fine-needle biopsy (FNB) needles be preferred over conventional fine-needle aspiration (FNA) needles for EUS-TA of subepithelial lesions. For solid pancreatic masses, rapid on-site evaluation is not routinely recommended when FNB needles are used. For dedicated FNB needles, fork-tip and Franseen-tip needles have essentially equivalent performance.

CONCLUSION

This consensus provides guidance for EUS-TA, thereby enhancing the quality of EUS-TA.

Comparative Assessment of Endoscopic Ultrasound-Guided Biopsies vs. Percutaneous Biopsies of Pancreatic Lesions: A Systematic Review and Meta-Analysis of Diagnostic Performance

Introduction: Pancreatic cancer ranks as the fourth deadliest form of cancer. However, it is essential to note that not all pancreatic masses signal primary malignancy. Therefore, it is imperative to establish the correct differential diagnosis, a process further supported by pre-operative biopsy procedures. This meta-analysis aims to compare the diagnostic performance of two minimally invasive biopsy approaches for pancreatic tissue sampling: percutaneous biopsies guided by computed tomography or ultrasound, and transduodenal biopsies guided by endoscopic ultrasound (EUS). Methods: A systematic literature search was conducted in the MEDLINE and Scopus databases. The included studies analyzed the diagnostic performance of the two biopsy methods, and they were assessed for risk of bias using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Statistical analysis was carried out using the RevMan and MetaDisc software packages. Results: The statistical analysis of the results demonstrated the superiority of the percutaneous approach. Specifically, the pooled sensitivity, specificity, LR+, LR-and DOR for the percutaneous approach were 0.896 [95% CI: 0.878-0.913], 0.949 [95% CI: 0.892-0.981], 9.70 [95% CI: 5.20-18.09], 0.20 [95% CI: 0.12-0.32] and 68.55 [95% CI: 32.63-143.98], respectively. The corresponding values for EUS-guided biopsies were 0.806 [95% CI: 0.775-0.834], 0.955 [95% CI: 0.926-0.974], 12.04 [95% CI: 2.67-54.17], 0.24 [95% CI: 0.15-0.39] and 52.56 [95% CI: 13.81-200.09], respectively. Nevertheless, it appears that this statistical superiority is also linked to the selection bias favoring larger and hence more readily accessible tumors during percutaneous biopsy procedures. Conclusions: Concisely, our meta-analysis indicates the statistical superiority of the percutaneous approach. However, selecting the optimal biopsy method is complex, influenced by factors like patient and tumor characteristics, clinical resources, and other relevant considerations.

Endoscopic ultrasound-guided fine-needle aspiration for gastrointestinal subepithelial lesions

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the first-choice procedure for obtaining pathological tissue samples from gastrointestinal (GI) subepithelial lesions (SELs). However, its diagnostic accuracy is lower than that for pancreatic masses owing to puncture difficulty and the need for immunostaining for definitive diagnosis. The advent of fine-needle biopsy needles, which have become well known in recent years, improves the diagnostic accuracy of EUS-FNA for GI SELs. The forward-viewing echoendoscope and rapid on-site evaluation (ROSE) have also helped to improve diagnostic accuracy. Furthermore, in facilities where ROSE is not available, endosonographers perform a macroscopic on-site evaluation. With these procedural innovations, EUS-FNA is now performed aggressively even for SELs smaller than 20 mm. The incidence of procedure-related adverse events such as bleeding and infection is low, and thus, EUS-FNA can be safely performed to diagnose SELs.

Advances and efficacy in specimen handling for endoscopic ultrasound-guided fine needle aspiration and biopsy: A comprehensive review

Endoscopic ultrasound-guided fine needle aspiration and biopsy have significantly evolved since they offer a minimally invasive approach for obtaining pathological specimens from lesions adjacent to or within the intestine. This paper reviews advancements in endoscopic ultrasound-guided fine needle aspiration and biopsy techniques and devices, emphasizing the importance of handling specimens for diagnostic accuracy. Innovations of fine needle biopsy needles with features like side holes and Franseen shapes have enhanced histological sampling capabilities. Techniques for specimen handling, including rapid on-site evaluation and macroscopic on-site evaluation, play pivotal roles in assessing sample adequacy, thereby influencing diagnostic outcomes. The utility of artificial intelligence in augmenting rapid on-site evaluation and macroscopic on-site evaluation, although still in experimental stages, presents a promising avenue for improving procedural efficiency and diagnostic precision. The choice of specimen handling technique is dependent on various factors including endoscopist preference, procedure objectives, and available resources, underscoring the need for a comprehensive understanding of each method's characteristics to optimize diagnostic efficacy and procedural safety.

Cutting edge of endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic lesions

This article provides an extensive review of the advancements and future perspectives related to endoscopic ultrasound-guided tissue acquisition (EUS-TA) for the diagnosis of solid pancreatic lesions (SPLs). EUS-TA, including fine-needle aspiration (EUS-FNA) and fine-needle biopsy (EUS-FNB), has revolutionized the collection of specimens from intra-abdominal organs, including the pancreas. Improvements in the design of needles, collection methods, and specimen processing techniques have improved the diagnostic performance. This review highlights the latest findings regarding needle evolution, actuation number, sampling methods, specimen evaluation techniques, application of artificial intelligence (AI) for diagnostic purposes, and use of comprehensive genomic profiling (CGP). It acknowledges the rising use of Franseen and fork-tip needles for EUS-FNB and emphasizes that the optimal number of actuations requires further study. Methods such as the door-knocking and fanning techniques have shown promise for increasing diagnostic performance. Macroscopic on-site evaluation (MOSE) is presented as a practical rapid specimen evaluation method, and the integration of AI is identified as a potentially impactful development. The study also underscores the importance of optimal sampling for CGP, which can enhance the precision of cancer treatment. Ongoing research and technological innovations will further improve the accuracy and efficacy of EUS-TA.

Clinical value of endoscopic ultrasound sound speed in differential diagnosis of pancreatic solid lesion and prognosis of pancreatic cancer

BACKGROUND

Differential diagnosis of pancreatic solid lesion (PSL) and prognosis of pancreatic cancer (PC) is a clinical challenge. We aimed to explore the differential diagnostic value of sound speed (SS) obtained from endoscopic ultrasonography (EUS) in PSL and the prognostic value of SS in PC.

METHODS

Patients with PSL in The Third Xiangya Hospital of Central South University from March 2019 to October 2019 were prospectively enrolled, who obtained SS from PSL. Patients were divided into the PC group and the pancreatic benign lesion (PBL) group. SS1 is the SS of lesions and SS2 is the SS of normal tissues adjacent to lesions. Ratio1 is equal to SS1 divided by SS2 of PSL (ratio1 = SS1/SS2).

RESULTS

Eighty patients were enrolled (24 PBL patients, 56 PC patients). SS1 and ratio1 in PC group were higher compared with PBL group (SS1:1568.00 vs. 1550.00, Z = -2.066, p = 0.039; ratio1: 1.0110 vs. 1.0051, Z = -3.391, p = 0.001). The SS1 in PC (Z = -6.503, p < 0.001) was higher compared to SS2. In the nonsurgical group of PC, low ratio1 predicted high overall survival (OS) (7.000 months vs. 4.000 months; p = 0.039). In the surgical group of PC, low SS1 was associated with low median OS (4.000 months vs. 12.000 months; p = 0.033).

CONCLUSIONS

SS plays a vital role in distinguishing between PBL and PC. Higher SS1 and ratio1 obtained by EUS are more related to PC than PBL. In PC patients, high SS1 may predict pancreatic lesions. In the nonsurgical group of PC, low ratio1 may predict high OS. However, in the surgical group of PC, low SS1 may predict low OS.

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.

Simultaneous establishment of pancreatic cancer organoid and cancer-associated fibroblast using a single-pass endoscopic ultrasound-guided fine-needle biopsy specimen

Considering the critical roles of cancer-associated fibroblasts (CAFs) in pancreatic cancer, recent studies have attempted to incorporate stromal elements into organoid models to recapitulate the tumor microenvironment. This study aimed to evaluate the feasibility of patient-derived organoid (PDO) and CAF cultures by using single-pass endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) samples from prospectively enrolled pancreatic cancer patients. The obtained samples were split into two portions for PDO and CAF cultures. PDOs and CAFs were cultured successfully in 54.4% (31/57) and 47.4% (27/57) of the cases, respectively. Both components were established in 21 cases (36.8%). Various clinicopathologic factors, including the tumor size, tumor location, clinical stage, histologic subtype, and tumor differentiation, did not influence the PDO establishment. Instead, the presence of necrosis in tumor samples was associated with initial PDO generation but no further propagation beyond passage 5 (P = 0.024). The "poorly cohesive cell carcinoma pattern" also negatively influenced the PDO establishment (P = 0.018). Higher stromal proportion in tumor samples was a decisive factor for successful CAF culture (P = 0.005). Our study demonstrated that the coestablishment of PDOs and CAFs is feasible even with a single-pass EUS-FNB sample, implying an expanding role of endoscopists in future precision medicine.

Macroscopic on‑site quality evaluation of biopsy specimens to improve the diagnostic accuracy of endoscopic ultrasound‑guided fine needle aspiration using a 22‑gauge needle for solid lesions: A single‑center retrospective study

The present study aimed to evaluate the clinical value of macroscopic on-site evaluation (MOSE) of solid masses by endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) using a standard 22-gauge needle and to explore the cut-off length of macroscopic visible core (MVC) required to obtain an accurate histopathological diagnosis. In total, 119 patients who satisfied the inclusion and exclusion criteria and underwent EUS-FNA were divided into conventional FNA and FNA combined with MOSE groups. In the MOSE group, the presence of MVC was examined and its total length measured, after which the pathological results of FNA were compared with the final diagnosis. The diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of FNA in the two groups were calculated and the effect of MOSE on the FNA result was analyzed. The MOSE group had a higher diagnostic sensitivity (75.0% vs. 89.8%; P=0.038) and accuracy (74.5% vs. 90.6%; P=0.026). MVC was observed in 98.4% (63/64) of patients in the MOSE group. The median length of MVC was 15 mm. The optimal cut-off length of MVC for obtaining an accurate histological diagnosis was 13 mm, with a sensitivity of 90.2%. No statistically significant significance was observed in the specificity, PPV and NPV between the groups. Thus, MOSE helps to improve the diagnostic ability of FNA for solid masses and may be a useful alternative to assess the adequacy of puncture specimens in units where rapid on-site evaluation cannot be performed.

EUS-Guided Diagnosis of Gastric Subepithelial Lesions, What Is New?

Gastric subepithelial lesions (SELs) are intramural lesions that arise underneath the gastric mucosa. SELs can be benign, but can also be malignant or have malignant potential. Therefore, correct diagnosis is crucial. Endosonography has been established as the diagnostic gold standard. Although the identification of some of these lesions can be carried out immediately, solely based on their echo characteristics, for certain lesions histological examination is necessary. Sometimes histology can be inconclusive, especially for smaller lesions. Therefore, new methods have been developed in recent years to assist decision making, such as contrast enhanced endosonography, EUS elastography, and artificial intelligence systems. In this narrative review we provide a complete overview of the gastric SELs and summarize the new data of the last ten years concerning the diagnostic advances of endosonography on this topic.

Endoscopic ultrasound-guided fine-needle biopsy with or without macroscopic on-site evaluation: a randomized controlled noninferiority trial

BACKGROUND : The advantage of using the macroscopic on-site evaluation (MOSE) technique during endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) performed with 22G Franseen needles has not been investigated. We aimed to compare EUS-FNB with MOSE vs. EUS-FNB performed with three needle passes. METHODS : This randomized trial involved 10 Italian referral centers. Consecutive patients referred for EUS-FNB of pancreatic or nonpancreatic solid lesions were included in the study and randomized to the two groups. MOSE was performed by gross visualization of the collected material by the endoscopists and considered adequate when a white/yellowish aggregate core longer than 10 mm was retrieved. The primary outcome was diagnostic accuracy. Secondary outcomes were specimen adequacy, number of needle passes, and safety. RESULTS : 370 patients with 234 pancreatic lesions (63.2 %) and 136 nonpancreatic lesions (36.8 %) were randomized (190 EUS-FNB with MOSE and 180 with standard EUS-FNB). No statistically significant differences were found between EUS-FNB with MOSE and conventional EUS-FNB in terms of diagnostic accuracy (90.0 % [95 %CI 84.8 %-93.9 %] vs. 87.8 % [95 %CI 82.1 %-92.2 %]; P = 0.49), sample adequacy (93.1 % [95 %CI 88.6 %-96.3 %] vs. 95.5 % [95 %CI 91.4 %-98 %]; P = 0.31), and rate of adverse events (2.6 % vs. 1.1 %; P = 0.28). The median number of passes was significantly lower in the EUS-FNB with MOSE group (1 vs. 3; P < 0.001). CONCLUSIONS : The accuracy of EUS-FNB with MOSE is noninferior to that of EUS-FNB with three needle passes. MOSE reliably assesses sample adequacy and reduces the number of needle passes required to obtain the diagnosis with a 22G Franseen needle.

Diagnostic accuracy of EUS-guided fine-needle biopsy sampling by macroscopic on-site evaluation: a systematic review and meta-analysis

BACKGROUND AND AIMS

Assessment of EUS-guided fine-needle tissue acquisition by macroscopic on-site evaluation (MOSE) is gathering attention. Studies report good diagnostic parameters with MOSE; however, the overall data are limited. We conducted this systematic review and meta-analysis to report on the pooled diagnostic assessment parameters of EUS-guided tissue acquisition by MOSE using fine-needle biopsy sampling (FNB).

METHODS

Multiple databases were searched (from inception to December 2021), and studies that reported on the diagnostic assessment of EUS-guided tissue acquisition by MOSE were selected. Pooled diagnostic accuracy, sensitivity, specificity, and positive and negative predictive values were calculated by standard meta-analysis methods following the random-effects model. Heterogeneity was assessed by I² statistics.

RESULTS

Fourteen studies were included in the analysis, and 1508 lesions were biopsy sampled in 1489 patients undergoing EUS-guided tissue acquisition. MOSE definition included a visible core of tissue with opacity and "wormlike" features of adequate size and length (≥4 mm). The pooled accuracy of FNA and/or FNB specimens in yielding a pathologic diagnosis by MOSE was 91.3% (95% confidence interval [CI], 88.6-93.3; I² = 66%), pooled sensitivity was 91.5% (95% CI, 88.6-93.6; I² = 66%), pooled specificity was 98.9% (95% CI, 96.6-99.7; I² = 80%), pooled positive predictive value was 98.8% (95% CI, 97.4-99.5; I² = 33%), and pooled negative predictive value was 55.5% (95% CI, 46.9-63.9; I² = 95%). Subgroup analyses by newer-generation FNB needles demonstrated similar pooled rates, with minimal adverse events (2.5%; 95% CI, 1.5-3.9; I² = 21%).

CONCLUSIONS

Excellent pooled diagnostic accuracy parameters were demonstrated in EUS-guided tissue acquisition by FNB using the MOSE method.

Diagnostic performance of endoscopic ultrasonography-guided fine-needle biopsy in upper gastrointestinal subepithelial tumors measuring 2-5 cm in size

BACKGROUND

Subepithelial tumors (SETs) in the upper gastrointestinal (GI) tract are frequently discovered during upper endoscopy, and their management is determined based on size and histopathological diagnosis. We aimed to evaluate the diagnostic performance of endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) in upper GI SETs of 2-5 cm in size.

METHODS

We included 63 patients who underwent EUS-FNB for upper GI SETs of 2-5 cm in size between January 2013 and February 2020. The diagnostic yield of EUS-FNB, ability of EUS-FNB in discriminating malignant from non-malignant lesions, and histopathological concordance between EUS-FNB specimens and resected specimens were evaluated.

RESULTS

Successful acquisition of macroscopic tissue cores was possible in all 63 cases, and the diagnostic yield of EUS-FNB was 92.1% (58/63). The sensitivity, specificity, and accuracy of EUS-FNB in discriminating malignant from non-malignant lesions were 100% (95% confidence interval [CI] 85.3-100%), 87.8% (95% CI 79.9-87.8%), and 92.1% (95% CI 81.8-92.1%), respectively. Of the 26 SETs that were endoscopically or surgically resected after EUS-FNB, the histopathological concordance rate between the EUS-FNB specimens and resected specimens was 100% (24/24), except in two cases of inadequate results with EUS-FNB specimens.

CONCLUSION

EUS-FNB provides high diagnostic yield and high capability in discriminating malignant from non-malignant lesions in upper GI SETs of 2-5 cm in size.

Tumor Location in the Head/Uncinate Process and Presence of Fibrosis Impair the Adequacy of Endoscopic Ultrasound-Guided Tissue Acquisition of Solid Pancreatic Tumors

Simple Summary

Endoscopic ultrasound-guided tissue acquisition is the most accurate method to diagnose pancreatic tumors; nevertheless, this technique does not always bring adequate diagnostic accuracy. This study aimed to identify which factors can impair its adequacy. Pancreatic cytological and histological aspirates were retrospectively assessed according to two scores for grading the adequacy and the fibrosis of the specimens. The performance of the biopsies was lower when the tumor was located in the head/uncinate process of the pancreas, probably due to the higher fibrosis that we found in these sites. The specimens were less adequate also when <3 needle passes were performed and when the cell block was not done. We demonstrated the benefit to assess the presence of fibrosis in the specimens because it increased the risk of false negative results.

Abstract

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) of solid pancreatic tumors shows optimal specificity despite fair sensitivity, with an overall suboptimal diagnostic yield. We aim to quantify the adequacy and accuracy of EUS-TA and assess predictive factors for success, focusing on the presence and degree of specimen fibrosis. All consecutive EUS-TA procedures were retrieved, and the specimens were graded for sample adequacy and fibrosis. The results were evaluated according to patients’ and tumor characteristics and the EUS-TA technique. In total, 407 patients (59% male, 70 [63–77] year old) were included; sample adequacy and diagnostic accuracy were 90.2% and 94.7%, respectively. Fibrosis was significantly more represented in tumors located in the head/uncinate process (p = 0.001). Tumor location in the head/uncinate (OR 0.37 [0.14–0.99]), number of needle passes ≥ 3 (OR 4.53 [2.22–9.28]), and the use of cell block (OR 8.82 [3.23–23.8]) were independently related to adequacy. Severe fibrosis was independently related to false negative results (OR 8.37 [2.33–30.0]). Pancreatic tumors located in the head/uncinate process showed higher fibrosis, resulting in EUS-TA with lower sample adequacy and diagnostic accuracy. We maintain that three or more needle passes and cell block should be done to increase the diagnostic yield.

Comparison of 22-gauge standard and Franseen needles in EUS-guided tissue acquisition for diagnosing solid pancreatic lesions: a multicenter randomized controlled trial

BACKGROUND AND AIMS

This large multicenter randomized controlled trial compared the diagnostic yields of 22-gauge standard and 22-gauge Franseen needles for EUS-guided tissue acquisition (EUS-TA) of solid pancreatic lesions.

METHODS

Consecutive patients with solid pancreatic lesions were prospectively randomized to EUS-TA using standard or Franseen needles. Samples obtained with the first needle pass and with second and subsequent passes were evaluated separately. The primary endpoint was the rate of accuracy for diagnosis of malignancy. Other endpoints were technical success rate, sample cellularity, adverse events, diagnostic accuracy in patient subgroups, and the diagnostic accuracy and numbers of second and subsequent needle passes.

RESULTS

Of 523 patients undergoing EUS-TA, 260 were randomized to using standard 22-gauge needles and 263 to 22-gauge Franseen needles. The technical success rate in each group was 99.6%, with similar adverse event rates in the standard (1.5%) and Franseen (.8%) needle groups. First-pass EUS-TA using the Franseen needle resulted in significantly greater diagnostic accuracy (84.0% vs 71.2%, P < .001) and sensitivity (82.4% vs 66.7%, P < .001) than first-pass EUS-TA using a standard needle and also resulted in superior diagnostic accuracy in patients requiring immunostaining. Second and subsequent EUS-TA using Franseen needles showed significantly greater accuracy (94.7% vs 90.0%, P = .049) and sensitivity (94.0% vs 88.6%, P = .047) and required fewer needle passes (1.81 vs 2.03, P = .008) than using standard needles.

CONCLUSIONS

EUS-TA with the Franseen needle is superior to EUS-TA with a standard needle with respect to diagnostic accuracy per pass, particularly in patients who require immunostaining, and number of passes when using macroscopic on-site evaluation. (Clinical trial registration numbers: UMIN000030634 and jRCTs052180062.).

The diagnostic performance of combined conventional cytology with smears and cell block preparation obtained from endoscopic ultrasound-guided fine needle aspiration for intra-abdominal mass lesions

BACKGROUND/AIM

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the primary method for tissue acquisition of intra-abdominal masses. However, the main limitation of cytology alone is the lack of tissue architecture and inadequate samples. This study aimed to evaluate the diagnostic performance of combined conventional cytology and cell block preparation obtained from EUS-FNA of intra-abdominal masses without Rapid On-site Evaluation (ROSE).

METHODS

Cytologic smears and cell block slides of 166 patients undergoing EUS-FNA during 2010-2015 were reviewed by an experienced cytopathologist blinded to clinical data.

RESULTS

125 patients had neoplastic lesions. Pancreatic adenocarcinoma was the most common etiology (35.5%), followed by lymph node metastasis (27.7%). The mean mass size was 2.5±1.3 cm. The mean number of passes was 1.9±1.28. Tissue adequacy for conventional cytology and cell block preparation was 78.9% and 78.1%, respectively. Factors associated with tissue adequacy were assessed. For cytology, lesions of > 2.1 cm, masses in the pancreatic body or tail, malignancy, and pancreatic cancer were positively associated with adequate cellularity. For cell block preparation, lesions of > 3 cm and malignancy were associated with increased tissue adequacy. The conventional cytology alone had a sensitivity of 68.5%, a specificity of 95.7%, and an area under the receiver operating characteristics (AUROC) of 0.821. The cell block preparation alone had a sensitivity of 65.4%, a specificity of 96%, and an AUROC of 0.807. The combined conventional cytology and cell block preparation performed significantly better than either method alone (p<0.05), as demonstrated by an increased AUROC of 0.853. Furthermore, cell block detected malignancy in 9.3% of cases where the cytologic smears failed to identify malignant cells.

CONCLUSIONS

The combined conventional cytology and cell block preparation increased the diagnostic accuracy of EUS-FNA compared to either method alone. This approach should be implemented in routine practice, especially where ROSE is unavailable.

Endoscopic Ultrasound-Guided Fine-Needle Biopsy Using 22G Franseen Needles without Rapid On-Site Evaluation for Diagnosis of Intraabdominal Masses

Background: The impact of rapid on-site cytologic evaluation (ROSE) on endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is widely debated. This study aims to assess the diagnostic performance of EUS-FNB in the absence of ROSE in abdominal masses. Methods: Patients with abdominal masses undergoing EUS-FNB using 22-gauge Franseen needles and the slow-pull technique were prospectively enrolled in this study. Macroscopic on-site evaluation (MOSE) was performed without ROSE. Results: 100 patients were recruited between 2018 and 2020. Seventy-eight patients had neoplasms, and twenty-two patients had benign diseases. Common diagnoses included pancreatic cancer (n = 27), mesenchymal tumors (n = 17), and metastatic tumors (n = 14). The mean mass size was 3.9 ± 2.6 cm. The median pass number was three. Eighty-nine percent had adequate specimens for histologic evaluation. Malignancy increased the odds of obtaining adequate tissue (OR 5.53, 95% CI, 1.36–22.5). For pancreatic cancer, FNB had a sensitivity of 92.3%, a specificity of 100%, a positive predictive value (PPV) of 100%, a negative predictive value (NPV) of 97%, and an AUROC of 0.96. The sensitivity, specificity, PPV, NPV, and AUROC for mesenchymal cell tumors were 100%, 95.9%, 84.2%, 100%, and 0.98, respectively. For metastatic tumors, FNB was 100% sensitive and specific, with an AUROC of 1.00. There were no procedure-related complications. Conclusions: 22-gauge Franseen needles with the slow-pull technique and MOSE without ROSE provide excellent diagnostic performances for malignant lesions. Thus, MOSE should be implemented in real-world practice, and ROSE can be obviated when EUS-FNB is employed.

Development of a Novel Evaluation Method for Endoscopic Ultrasound-Guided Fine-Needle Biopsy in Pancreatic Diseases Using Artificial Intelligence

We aimed to develop a new artificial intelligence (AI)-based method for evaluating endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) specimens in pancreatic diseases using deep learning and contrastive learning. We analysed a total of 173 specimens from 96 patients who underwent EUS-FNB with a 22 G Franseen needle for pancreatic diseases. In the initial study, the deep learning method based on stereomicroscopic images of 98 EUS-FNB specimens from 63 patients showed an accuracy of 71.8% for predicting the histological diagnosis, which was lower than that of macroscopic on-site evaluation (MOSE) performed by EUS experts (81.6%). Then, we used image analysis software to mark the core tissues in the photomicrographs of EUS-FNB specimens after haematoxylin and eosin staining and verified whether the diagnostic performance could be improved by applying contrastive learning for the features of the stereomicroscopic images and stained images. The sensitivity, specificity, and accuracy of MOSE were 88.97%, 53.5%, and 83.24%, respectively, while those of the AI-based diagnostic method using contrastive learning were 90.34%, 53.5%, and 84.39%, respectively. The AI-based evaluation method using contrastive learning was comparable to MOSE performed by EUS experts and can be a novel objective evaluation method for EUS-FNB.

Impact of Macroscopic On-Site Evaluation (MOSE) on Accuracy of Endoscopic Ultrasound-Guided Fine-Needle Biopsy (EUS-FNB) of Pancreatic and Extrapancreatic Solid Lesions: A Prospective Study

This is a prospective and comparative study including 76 consecutive patients performing EUS-FNB for pancreatic and extrapancreatic solid lesions, randomized by alternate allocation to macroscopic on-site evaluation (MOSE) (40 patients) or to a conventional technique (40 patients), with three passes each. MOSE samples were differentiated into score 0: no visible material, score 1: only necrotic or haematic material, score 2: white core tissue ≤ 2 mm, or score 3: white core tissue > 2 mm. The conventional technique consisted in pushing all the needle content into a test tube for evaluation by the pathologist. In both groups, a 22–25 Gauge Franseen-tip needle (Acquire, Boston Scientific Co., Natick, MA, USA) was used. The study evaluated the diagnostic accuracy and adequacy of MOSE compared to the conventional technique and whether MOSE could optimize the number of passes during EUS-FNB. Results: The analysis was performed on 76 patients (38 MOSE, 38 conventional). The overall diagnostic adequacy was 94.7% (72/76) and accuracy was 84.2% (64/76). The diagnostic accuracy was similar in the two groups: MOSE 86.8% (33/38 lesions), vs. conventional 81.6%, 31/38 lesions, p = 0.76). Regarding diagnostic adequacy, the MOSE technique was 97.4% (111/114 passes) compared to 92.1% (105/114 passes) with the conventional technique, p = 0.06. The accuracy increased according to the MOSE score evaluation: it was 43.5%, 65.5% and 78.3% in patients with score 1, score 2, and score 3, respectively. Moreover, if in the first two passes the MOSE score was 2 or 3, the accuracy was 82.6% (20/23), and upon adding a third pass, the accuracy increased to 87% (20/23), which was not significantly different from the general accuracy of the MOSE samples (86.8%) (p = 0.86). Conclusions: The MOSE score showed a comparable diagnostic accuracy to the conventional technique. However, MOSE allows endoscopists to perform an inspective evaluation of the material, tends to perform better than the conventional technique in terms of diagnostic adequacy, and may potentially reduce the number of passes.

Usefulness of Macroscopic On-Site Evaluation Using a Stereomicroscope during EUS-FNB for Diagnosing Solid Pancreatic Lesions

METHODS

We reviewed a total of 60 consecutive patients who underwent both S-MOSE and rapid on-site cytopathological evaluation (ROSE) during EUS-FNB between July 2019 and October 2020, and the usefulness of S-MOSE in comparison with histology was evaluated. A 22-gauge Franseen needle was used to perform EUS-FNB in all patients, and only the specimens obtained by the first pass were evaluated. The final diagnosis was based on the surgical specimen or the clinical course consistent with the EUS-FNB results.

RESULTS

The final diagnoses of the 60 patients included 45 patients with pancreatic ductal adenocarcinoma, 6 with autoimmune pancreatitis, 4 with mass-forming pancreatitis, 1 with pancreatic metastasis, 2 with pancreatic neuroendocrine tumor, and 2 with intraductal papillary mucinous carcinoma. The histological diagnostic accuracy of the first pass of EUS-FNB was 83.3% (50/60). The agreement between the S-MOSE and the histological diagnosis was 90% (54/60). The positive predictive value of S-MOSE for histological diagnosis was 90.7%, which can be an indicator of when to stop the EUS-FNB procedure. There were no immediate or delayed adverse events reported after the FNB based on the chart and medical visit history review.

CONCLUSION

In the EUS-FNB of SPLs, S-MOSE can be an alternative to ROSE for specimen evaluation and has the potential to shorten the procedure time.

GIE Editorial Board top 10 topics: advances in GI endoscopy in 2020

The American Society for Gastrointestinal Endoscopy's Gastrointestinal Endoscopy Editorial Board reviewed a systematic literature search of original endoscopy-related articles published during 2020 in Gastrointestinal Endoscopy and 10 other high-impact medical and gastroenterology journals. Votes from each individual board member were tallied to identify a consensus list of the 10 most significant topic areas in GI endoscopy over the calendar year of study using 4 criteria: significance, novelty, impact on national health, and impact on global health. The 10 areas identified were as follows: artificial intelligence in endoscopy, coronavirus disease 2019 and GI practice, third-space endoscopy, lumen-apposing metal stents, single-use duodenoscopes and other disposable equipment, endosonographic needle technology and techniques, endoscopic closure devices, advances in GI bleeding management, improvements in polypectomy techniques, and bariatric endoscopy. Each board member contributed a summary of important articles relevant to 1 to 2 topic areas, leading to a collective summary that is presented in this document of the "top 10" endoscopic advances of 2020.

Macroscopic on-site evaluation (MOSE) of specimens from solid lesions acquired during EUS-FNB: multicenter study and comparison between needle gauges

Background and study aims  The standard method for obtaining samples during endoscopic ultrasonography (EUS) is fine-needle aspiration (FNA), the accuracy of which can be affected by the presence of a cytopathologist in endoscopy room (rapid on-site evaluation [ROSE]). With the introduction of fine-needle biopsy (FNB), macroscopic on-site evaluation (MOSE) of a acquired specimen has been proposed. Only a few studies have evaluated the role of MOSE and in all except one, a 19G needle was used. Our primary aim was to evaluate the diagnostic yield and accuracy of MOSE with different needle sizes and the secondary aim was to identify factors influencing the yield of MOSE. Patients and methods  Data from patients who underwent EUS-FNB for solid lesions, with MOSE evaluation of the specimen, were collected in six endoscopic referral centers. Results  A total of 378 patients (145 F and 233 M) were enrolled. Needles sizes used during the procedures were 20G (42 %), 22G (45 %), and 25G (13 %). The median number of needle passes was two (IQR 2-3). The overall diagnostic yield of MOSE was of 90 % (confidence interval [CI] 86 %-92 %). On multivariable logistic regression analysis, variables independently associated with the diagnostic yield of MOSE were a larger needle diameter (20G vs. 25G, OR 11.64, 95 %CI 3.5-38.71; 22G vs. 25G, OR 6.20, 95 %CI 2.41-15.90) and three of more needle passes (OR 3.39, 95 %CI 1.38-8.31). Conclusions  MOSE showed high diagnostic yield and accuracy. Its yield was further increased if performed with a large size FNB needles and more than two passes.

The evolving role of EUS-guided tissue acquisition

The introduction of endoscopic ultrasound-guided fine-needle aspiration into clinical practice was a pivotal moment for diagnostic gastrointestinal endoscopy. It facilitates the ease of tissue acquisition from previously inaccessible sites. The performance characteristics of cytological diagnosis are excellent. However, there remain areas of inadequacies. These include procedural inefficiencies such as the need for rapid on-site cytological evaluation or macroscopic on-site evaluation, the crucial role of histology for diagnosis in specific conditions, the issue of sampling errors and the need for repeat procedures, and the shift towards personalized medicine, which requires histology, immunohistochemical studies, and molecular analysis. The original Trucut biopsy needle had been cumbersome to use, but the recent introduction of newer-generation biopsy needles has transformed the landscape, such that there is now a greater focus on tissue acquisition for histological assessment. Concomitant technological advances of endoscopic ultrasound processors enabled higher-resolution imaging, and facilitated image enhancement using contrast harmonic endoscopic ultrasound and endoscopic ultrasound elastography. These techniques can be used as an adjunct to guide tissue acquisition in challenging situations. There is ongoing research on the use of artificial intelligence to complement diagnostic endoscopic ultrasound and the early data are promising. Artificial intelligence may be especially important to guide clinical decision-making if biopsy results are nondiagnostic.