Comparing Needles and Methods of Endoscopic Ultrasound-Guided Fine-Needle Biopsy to Optimize Specimen Quality and Diagnostic Accuracy for Patients With Pancreatic Masses in a Randomized Trial

Outcomes of Endoscopic Ultrasound-guided Fine Needle Biopsy Using a Novel Hydrostatic Stylet Tissue Acquisition Technique

BACKGROUND

Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) is frequently used to obtain core samples of solid lesions. Here, we describe and evaluate a novel hydrostatic stylet (HS) technique designed to optimize core sample acquisition, reporting diagnostic yield, efficacy, and safety relative to the conventional stylet slow-pull (SP) technique.

METHODS

A novel HS technique was developed and validated retrospectively. Consecutive patients who underwent EUS-FNB with core biopsy of solid lesions through either the HS or SP technique between January 2020 and April 2022 were included. Exclusion criteria included cystic lesions, nonlesional liver biopsies, and specimens sent for cytologic analysis only. Patient and lesion characteristics, number of passes, sample adequacy, and adverse events were compared between the two techniques.

RESULTS

A total of 272 patients were included with 138 in the HS group and 134 in the SP group. Lesion size and anatomic distribution were similar in both groups. Compared with the SP approach, the HS technique demonstrated significantly higher sample adequacy (97.8% vs 83.6%, P < 0.001), higher sensitivity (97.1% vs 89.7%, P = 0.03), and lower mean number of passes (1.2 vs 3.3, P < 0.001). Rates and severity of adverse events in the HS group were comparable to the SP group and existing literature. Similar associations were observed in pancreatic and nonpancreatic lesion subanalyses.

CONCLUSIONS

The novel HS technique demonstrated excellent biopsy sample adequacy and diagnostic yield while requiring fewer passes to obtain diagnostic specimens compared with a conventional EUS-FNB approach. Further prospective evaluation is needed to confirm these pilot findings and optimize EUS-FNB acquisition techniques.

Feasibility of comprehensive genomic profiling using endoscopic ultrasound-guided tissue acquisition with a 22-gauge Franseen needle

Aim

Comprehensive genomic profiling (CGP) test for solid tumors is now increasingly utilized in clinical practice, especially in pancreatobiliary cancer, and specimens obtained by endoscopic ultrasound-guided tissue acquisition (EUS-TA) are often submitted for tissue-based CGP test. In this study, we evaluated the feasibility of EUS-TA using a 22-gauge Franseen needle for the CGP test.

Methods

Consecutive patients with solid tumors who underwent EUS-TA using a 22-gauge Franseen needle, and whose tissue samples were pre-checked for suitability for CGP test, were included in this single-center, retrospective analysis. The success rates of appropriate sample collection for CGP evaluated by pathologists (1st quality control) and CGP test (2nd quality control) were evaluated. In addition, The EUS-TA slides were evaluated for the tissue area and tumor area content, using the image software.

Results

A total of 50 cases, with 78% of pancreatic cancer, were included in the analysis. A median of 3 passes of EUS-TA were performed with an adverse event rate of 4%. The success rates for 1st and 2nd quality control for CGP tests were 86% and 76%, respectively. The image analyses suggested EUS-TA specimen did not always fulfill CGP test criteria, with 18% of tissue area ≥16 mm2 and 38% of tumor area content ≥20%, even in cases with successful CGP tests. The suction method yielded a significantly larger amount of DNA but without a significant difference in the multivariate analysis.

Conclusions

The present study demonstrated the feasibility of EUS-TA using a 22-gauge Franseen needle for CGP test.

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.

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.

Factors Influencing the Diagnostic Performance of Repeat Endoscopic Ultrasound-Guided Fine-Needle Aspiration/Biopsy after the First Inconclusive Diagnosis of Pancreatic Solid Lesions

Background/Aims

Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/B) is essential in diagnosing solid pancreatic lesions (SPLs), but without rapid on-site evaluation (ROSE), a repeat EUS-FNA/B is crucial for clarifying an inconclusive diagnosis. We aimed to evaluate factors associated with improved diagnostic performance of repeat EUS-FNA/B for initially inconclusive SPL diagnoses without ROSE.

Methods

Of 5,894 patients subjected to EUS-FNA/B, 237 (4.0%) with an initially inconclusive diagnosis of SPLs were retrospectively enrolled from five tertiary medical centers between January 2016 and June 2021. Diagnostic performance and procedural factors of EUS-FNA/B were analyzed.

Results

The diagnostic accuracies of first and repeat EUS-FNA/B were 96.2% and 67.6%, respectively. Of 237 patients with an inconclusive diagnosis from initial EUS-FNA/B, 150 were pathologically diagnosed after repeat EUS-FNA/B. In multivariate analysis of repeat EUS-FNA/B, tumor location (body/tail vs head: odds ratio [OR], 3.74; 95% confidence interval [CI], 1.48 to 9.46), number of needle passes (≥4 vs ≤3: OR, 4.80; 95% CI, 1.44 to 15.99), needle type (FNB vs FNA: OR, 3.26; 95% CI, 1.44 to 7.36), needle size (22 gauge vs 19/20 gauge: OR, 2.35; 95% CI, 1.19 to 4.62), and suction method (suction vs others: OR, 5.19; 95% CI, 1.30 to 20.75) were associated with a significantly improved diagnostic performance.

Conclusions

Repeat EUS-FNA/B is essential for patients with an inconclusive EUS-FNA/B without ROSE. To improve the diagnostic performance of repeated EUS-FNA/B, it is recommended that 22-gauge FNB needles, ≥4 needle passes, and suction methods are used.

Small biopsies for pancreatic lesions: Is there still room for fine needle aspiration?

Pancreatic carcinoma is an aggressive tumour with increasing incidence in both sexes worldwide. Early detection is, therefore, essential for patient management. A recent advancement involves the utilization of larger, thicker gauge needles, which enable the collection of core-type biopsies (FNB). Here, we investigated the role of fine needle aspiration and cytopathology in the diagnostic workflow of pancreatic lesions. A search query was designed to search for articles in the PubMed database comparing FNA and FNB for biopsy of pancreatic lesions, and detailed data were extracted from selected studies. Statistical analyses were performed using the R package meta version 6.2. Twenty-one studies made the final cut for data extraction. Overall, median age was 64.3 years (±6.1; 47.6-71.5), male: female proportion 53.9 (±11.3; 27.6-67.4), lesion size 3.1 cm (±0.5; 1.9-4.2 cm) and percentage of malignant cases 78.3% (±26.8; 2.1-100). FNA and FNB diagnostic yield was 85.8% (±10.3; 70.0-100.0) and 89.2% (±7.7; 70.0-98.6), respectively. Average accuracy was 89.5% (±11.7; 63.0-100.0) for FNA and 90.8% (±7.1; 77.0-100.0) for FNB. Adverse effects rate was 1.0% (±1.3; 0-4.3) for FNA and 2.2% (±4.4; 0-16.1) for FNB. None of the selected variables had a significant statistical difference between both methods. FNA and FNB perform similarly for diagnostic material acquisition in pancreatic lesions. The best outcome comes from the association of both techniques, emphasizing the value of combining cytological and histological morphology for the most accurate analysis.

Diagnostic accuracy of endoscopic ultrasonography-guided tissue acquisition prior to resection of pancreatic carcinoma: a nationwide analysis

INTRODUCTION

Endoscopic ultrasonography guided tissue acquisition (EUS + TA) is used to provide a tissue diagnosis in patients with suspected pancreatic cancer. Key performance indicators (KPI) for these procedures are rate of adequate sample (RAS) and sensitivity for malignancy (SFM).

AIM

assess practice variation regarding KPI of EUS + TA prior to resection of pancreatic carcinoma in the Netherlands.

PATIENTS AND METHODS

Results of all EUS + TA prior to resection of pancreatic carcinoma from 2014-2018, were extracted from the national Dutch Pathology Registry (PALGA). Pathology reports were classified as: insufficient for analysis (b1), benign (b2), atypia (b3), neoplastic other (b4), suspected malignant (b5), and malignant (b6). RAS was defined as the proportion of EUS procedures yielding specimen sufficient for analysis. SFM was calculated using a strict definition (malignant only, SFM-b6), and a broader definition (SFM-b5+6).

RESULTS

691 out of 1638 resected patients (42%) underwent preoperative EUS + TA. RAS was 95% (range 89-100%), SFM-b6 was 44% (20-77%), and SFM-b5+6 was 65% (53-90%). All centers met the performance target RAS>85%. Only 9 out of 17 met the performance target SFM-b5+6 > 85%.

CONCLUSION

This nationwide study detected significant practice variation regarding KPI of EUS + TA procedures prior to surgical resection of pancreatic carcinoma. Therefore, quality improvement of EUS + TA is indicated.

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.

Risk Factors and Interpretation of Inconclusive Endoscopic Ultrasound-Guided Fine Needle Aspiration Cytology in the Diagnosis of Solid Pancreatic Lesions

BACKGROUND

The inconclusive cytological findings of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) remain a major clinical challenge and often lead to treatment delays.

METHODS

Patients who had undergone EUS-FNA sampling for solid pancreas lesions between 2014 and 2021 were retrospectively enrolled. The "atypical" and "non-diagnostic" categories of the Papanicolaou Society of Cytopathology System were considered inconclusive and the "negative for malignancy" category of malignancy was suspected clinically. We determined the frequency and predictors of inconclusive cytological finding.

RESULTS

A total of 473 first EUS-FNA samples were included, of which 108 cases (22.83%) were inconclusive. Significant increases in the odds of inconclusive cytological findings were observed for lesions with a benign final diagnosis (OR 11.20; 95% CI 6.56-19.54, p < 0.001) as well as with the use of 25 G FNA needles (OR 2.12; 95% CI 1.09-4.01, p = 0.023) compared to 22 G needles. Furthermore, the use of a single EUS-FNA technique compared to the combined use of slow-pull and standard suction techniques (OR 1.70; 95% CI 1.06-2.70, p = 0.027) and less than three punctures per procedure led to an elevation in the risk of inconclusive cytology (OR 2.49; 95% CI 1.49-4.14, p < 0.001). Risk reduction in inconclusive cytology findings was observed in lesions between 2-4 cm (OR 0.40; 95% CI 0.23-0.68, p = 0.001) and >4 cm (OR 0.16; 95% CI 0.08-0.31, p < 0.001) compared to lesions ≤2 cm.

CONCLUSIONS

The more than two punctures per EUS-FNA sampling with larger-diameter needle (19 G or 22 G) using the slow-pull and standard suction techniques in combination may decrease the probability of inconclusive cytological findings.

Randomized trial comparing 15 vs 5 actuations per pass during endoscopic ultrasound-guided fine-needle biopsy for specimen acquisition of solid pancreatic lesions

BACKGROUND AND AIM

There is currently no established number of actuations (to-and-fro movements) per pass during endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). This study aimed to compare 15 vs 5 actuations in terms of adequate specimen acquisition of solid pancreatic lesions.

METHODS

In this prospective, randomized, crossover, noninferiority, single-center study, eligible patients underwent EUS-FNB using a 22-G Franseen needle with both 15 and 5 actuations per pass, performed in a randomized order, from October 2020 to December 2021. The acquired specimens from each pass were separately evaluated. The primary outcome was the accuracy of the histological diagnosis per pass. The noninferiority margin was set as 15%.

RESULTS

Data from 85 patients were analyzed, revealing pancreatic cancer in 73 patients. The accuracy of the histological diagnosis in the 15 and 5 actuations groups was 83.5% (71/85) and 77.7% (66/85), respectively. The difference was -5.8% (95% confidence interval -15.6-3.4), which does not indicate noninferiority of the five actuations group. Among the secondary outcomes, the 15 actuations group was significantly superior to the five actuations group in terms of the obtained core tissues (1.88 [interquartile range 0.89-3.64] mm2 vs 1.66 [0.83-2.71] mm2 [P = 0.031]) and subjective evaluation of cytology specimens for pancreatic cancer (69.0% vs. 31.0%, P = 0.005).

CONCLUSIONS

The noninferiority of five actuations in the accuracy of the histological diagnosis was not confirmed, and 15 actuations are preferred during EUS-FNB for solid pancreatic lesions.

Comparing per-pass performance of 2 types of needles for EUS-guided fine-needle biopsy sampling of pancreatobiliary masses in a randomized trial

BACKGROUND AND AIMS

EUS-guided fine-needle biopsy sampling (EUS-FNB) has largely replaced FNA for tissue diagnosis of pancreatobiliary mass lesions. However, the optimal number of passes required for the diagnosis of malignancy is not clear. We aimed to compare the per-pass performance of 2 types of fine-needle biopsy (FNB) needles for the detection of malignancy.

METHODS

One hundred fourteen patients referred for EUS evaluation of solid pancreatobiliary mass lesions underwent randomization between biopsy sampling with a Franseen needle and a 3-prong tip needle with an asymmetric cutting surfaces. Four passes of EUS-FNB were taken from each mass lesion. Two pathologists blinded to needle type analyzed the specimens. The final diagnosis of malignancy was made based on FNB specimen pathology, surgery, or a follow-up of at least 6 months after EUS-FNB. The sensitivity of EUS-FNB to diagnose malignancy was compared between the 2 groups. The cumulative sensitivity of detection of malignancy by EUS-FNB was calculated after each pass in each arm. Other characteristics of the specimens including cellularity and blood contents were also compared between the 2 groups. In the primary analysis, lesions categorized as suspicious on EUS-FNB were considered nondiagnostic for malignancy.

RESULTS

Ninety-eight patients (86%) had a final diagnosis of malignancy, and 16 patients (14%) had benign disease. Four passes of EUS-FNB with the Franseen needle detected malignancy in 44 of 47 patients (sensitivity, 93.6%; 95% confidence interval [CI], 82.5-98.7) and with the 3-prong asymmetric-tip needle in 50 of 51 patients (sensitivity, 98%; 95% CI, 89.6-99.9; P = .35). Two passes of EUS-FNB detected malignancy with a sensitivity of 91.5% (95% CI, 79.6-97.6) with the Franseen needle and 90.2% (95% CI, 78.6-96.7) with the 3-prong asymmetric-tip needle. The cumulative sensitivities at pass 3 were 93.6% (95% CI, 82.5-98.6) and 96.1% (95% CI, 86.5-99.5), respectively. Samples collected with the Franseen needle had significantly higher cellularity than samples collected with the 3-prong asymmetric-tip needle (P < .01). However, no difference as found between the 2 types of needles in term of specimen bloodiness.

CONCLUSIONS

No significant differences were found in the diagnostic performance of the Franseen needle versus the 3-prong asymmetric-tip needle in patients with suspected pancreatobiliary cancer. However, the Franseen needle yielded higher cellularity of the specimen. Two passes of EUS-FNB are required to detect malignancy with at least 90% sensitivity with either type of needle. (Clinical trial registration number: NCT04975620.).

Comparison of suction techniques for EUS-guided tissue acquisition: Systematic review and network meta-analysis of randomized controlled trials

Background and study aims Despite the widespread use of endoscopic ultrasound (EUS)-guided tissue acquisition, the choice of optimal suction technique remains a subject of debate. Multiple studies have shown conflicting results with respect to the four suction techniques: Dry suction (DS), no suction (NS), stylet slow-pull (SSP) and wet suction (WS). Thus, the present network meta-analysis (NMA) was conducted to compare the diagnostic yields of above suction techniques during EUS-guided tissue acquisition. Methods A comprehensive literature search from 2010 to March 2022 was done for randomized trials comparing the aspirated sample and diagnostic outcome with various suction techniques. Both pairwise and network meta-analyses were performed to analyze the outcomes: sample adequacy, moderate to high cellularity, gross bloodiness and diagnostic accuracy. Results A total of 16 studies (n=2048 patients) were included in the final NMA. WS was associated with a lower odd of gross bloodiness compared to DS (odds ratio 0.50, 95% confidence interval 0.24-0.97). There was no significant difference between the various suction methods with respect to sample adequacy, moderate to high cellularity and diagnostic accuracy. On meta-regression, to adjust for the effect of needle type, WS was comparable to DS in terms of bloodiness when adjusted for fine-needle aspiration needle. Surface under the cumulative ranking analysis ranked WS as the best modality for all the outcomes. Conclusions The present NMA did not show superiority of any specific suction technique for EUS-guided tissue sampling with regard to sample quality or diagnostic accuracy, with low confidence in estimates.

Efficacy of endoscopic ultrasound-guided tissue acquisition for solid pancreatic lesions 20 mm or less in diameter suspected as neuroendocrine tumors or requiring differentiation

BACKGROUND

For non-functioning pancreatic neuroendocrine tumors (pNETs) ≤ 20 mm, most guidelines consider follow-up observations as an option; however, the various treatment strategies are defined by size alone, even though the Ki-67 index is important for malignancy grading. Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is the standard for the histopathological diagnosis of solid pancreatic lesions; however, recent results for small lesions remain unclear. Therefore, we examined the efficacy of EUS-TA for solid pancreatic lesions ≤ 20 mm suspected as pNETs or requiring differentiation and the non-increase rate in tumor size in follow-up cases.

METHODS

We retrospectively analyzed data of 111 patients (median age = 58 years) with lesions ≤ 20 mm suspected as pNETs or requiring differentiation who underwent EUS-TA. All patients underwent specimen evaluation by rapid onsite evaluation (ROSE).

RESULTS

EUS-TA led to a diagnosis of pNETs in 77 patients (69.4%) and tumors other than pNETs in 22 patients (19.8%). The histopathological diagnostic accuracy of EUS-TA was 89.2% (99/111) overall, 94.3% (50/53) for 10-20 mm lesions, and 84.5% (49/58) for ≤ 10 mm lesions, with no significant difference in diagnostic accuracy (p = 0.13). The Ki-67 index was measurable in all patients with a histopathological diagnosis of pNETs. Among 49 patients with a diagnosis of pNETs who were followed up, one patient (2.0%) showed tumor enlargement.

CONCLUSIONS

EUS-TA for solid pancreatic lesions ≤ 20 mm suspected as pNETs or requiring differentiation is safe and has adequate histopathological diagnostic accuracy, suggesting that follow-up observations of pNETs with a histological pathologic diagnosis are acceptable in the short term.

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.

Wet-suction versus slow-pull technique for endoscopic ultrasound-guided fine-needle biopsy: a multicenter, randomized, crossover trial

BACKGROUND : It is unknown whether there is an advantage to using the wet-suction or slow-pull technique during endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) with new-generation needles. We aimed to compare the performance of each technique in EUS-FNB.

METHODS

 This was a multicenter, randomized, single-blind, crossover trial including patients with solid lesions of ≥ 1 cm. Four needle passes with 22 G fork-tip or Franseen-type needles were performed, alternating the wet-suction and slow-pull techniques in a randomized order. The primary outcome was the histological yield (samples containing an intact piece of tissue of at least 550 μm). Secondary end points were sample quality (tissue integrity and blood contamination), diagnostic accuracy, and adequate tumor fraction.

RESULTS

 Overall, 210 patients with 146 pancreatic and 64 nonpancreatic lesions were analyzed. A tissue core was retrieved in 150 (71.4 %) and 129 (61.4 %) cases using the wet-suction and the slow-pull techniques, respectively (P = 0.03). The mean tissue integrity score was higher using wet suction (P = 0.02), as was the blood contamination of samples (P < 0.001). In the two subgroups of pancreatic and nonpancreatic lesions, tissue core rate and tissue integrity score were not statistically different using the two techniques, but blood contamination was higher with wet suction. Diagnostic accuracy and tumor fraction did not differ between the two techniques.

CONCLUSION

 Overall, the wet-suction technique in EUS-FNB resulted in a higher tissue core procurement rate compared with the slow-pull method. Diagnostic accuracy and the rate of samples with adequate tumor fraction were similar between the two techniques.

EUS-guided liver biopsy using a novel hydrostatic stylet technique

Video 1Hydrostatic stylet technique for the performance of EUS-guided liver biopsy.

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.

GIE Editorial Board Top 10: advances in GI endoscopy in 2021

The 9-member Editorial Board of the American Society for Gastrointestinal Endoscopy performed a systematic literature search of original articles published during 2021 in Gastrointestinal Endoscopy and 10 other high-impact medical and gastroenterology journals on endoscopy-related topics. Votes from each editorial 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, with a focus on 3 criteria: significance, novelty, and global impact on clinical practice. The 10 areas identified collectively represent advances in the following endoscopic topics: colonoscopy optimization, bariatric endoscopy, endoscopic needle sampling and drainage, peroral endoscopic myotomy, endoscopic defect closure, meeting systemic challenges in endoscopic training and practice, endohepatology, FNA versus fine-needle biopsy sampling, endoscopic mucosal and submucosal procedures, and cold snare polypectomy. Each board member contributed a summary of important articles relevant to 1 to 2 of the consensus topic areas, leading to a collective summary that is presented in this document of the "top 10" endoscopic advances of 2021.

Needle bevel geometry influences the flexural deflection magnitude in ultrasound-enhanced fine-needle biopsy

It has been recently demonstrated that use of ultrasound increases the tissue yield in ultrasound-enhanced fine-needle aspiration biopsy (USeFNAB) as compared to conventional fine-needle aspiration biopsy (FNAB). To date, the association between bevel geometry and needle tip action has not been widely explored. In this study, we studied the needle resonance characteristics and deflection magnitude of various needle bevel geometries with varying bevel lengths. With a conventional lancet, having a 3.9 mm long bevel, the tip deflection-to-power ratio (DPR) in air and water was 220 and 105 µm/W, respectively. This was higher in comparison to an axi-symmetric tip, having a bevel length of 4 mm, which achieved a DPR of 180 and 80 µm/W in air and water, respectively. This study emphasised the importance of relationship between flexural stiffness of bevel geometry in the context of various insertion media and, thus, could provide understanding on approaches to control post-puncture cutting action by modifying the needle bevel geometry, essential for the USeFNAB application.

Comparison of Adverse Events of Different Endoscopic Ultrasound-Guided Tissue Acquisition Methods: A Single-Center Retrospective Analysis

The efficacy of new generation endoscopic ultrasound-guided biopsy needles has been promising in recent years. Yet, comparing these needles’ diagnostic yield and safety to conventional needles is not well-known. Our study aims to compare the adverse events of endoscopic ultrasound-guided tissue acquisition (EUS-TA) with different types of needles, including FNA needles, FNB needles with a Franseen tip and FNB needles with a reverse bevel. Furthermore, we will analyze the risk factors, including tumor vascularity, different needle types, and the underlying disease, which may impact the safety of the procedures. From May 2014 to December 2021, 192 consecutive EUS-TAs were performed on pancreatic and peripancreatic lesions in our hospital using different types of FNA and FNB needles. We retrospectively reviewed the data and identified the risk factors for EUS-TA-related complications. As a result, the hypervascular tumor is a significant risk factor for adverse events in our multivariate analysis, with an odds ratio of 4.96 (95% CI 1.33–18.47), while liver cirrhosis is one of the risk factors for adverse events during EUS-TA, with an odds ratio of 5.3 (95% CI 1.1–25.6). However, the risk of adverse events did not increase using Franseen-tip needles, compared to conventional FNA or FNB needles with a reverse bevel. In conclusion, we must be more cautious in patients with liver cirrhosis and hypervascular tumors, such as pancreatic neuroendocrine tumors, when performing EUS-guided tissue acquisition.

Comparative diagnostic performance of end-cutting fine-needle biopsy needles for EUS tissue sampling of solid pancreatic masses: a network meta-analysis

BACKGROUND AND AIMS

Evidence is limited on the comparative diagnostic performance of newer end-cutting fine-needle biopsy (FNB) needles for tissue sampling of pancreatic masses. We performed a systematic review with network meta-analysis to compare the diagnostic accuracy of available FNB needles for sampling of solid pancreatic lesions.

METHODS

A systematic literature review (Medline and Cochrane Database) was conducted for studies evaluating the accuracy of newer FNB needles in adults undergoing EUS-guided sampling of solid pancreatic masses. The primary outcome was diagnostic accuracy. Secondary outcomes were sample adequacy, diagnostic sensitivity, specificity, and adverse event rate. We performed pairwise and network meta-analyses and appraised the quality of evidence using Grading of Recommendations Assessment, Development and Evaluation methodology.

RESULTS

Overall, 16 RCTs (1934 patients) were identified. On network meta-analysis, Franseen needles (Acquire; Boston Scientific, Marlborough, Mass, USA) significantly outperformed reverse-bevel needles (risk ratio [RR], 1.21 [95% confidence interval {CI}, 1.05-1.40] for accuracy and 1.31 [95% CI, 1.05-1.22] for adequacy) and FNA needles (RR, 1.21 [95% CI, 1.01-1.25] for accuracy and 1.07 [95% CI, 1.02-1.13] for adequacy). Likewise, the Fork-tip needle (SharkCore; Medtronic, Dublin, Ireland) was significantly superior to the reverse-bevel needle (RR, 1.17 [95% CI, 1.03-1.33] for accuracy and 1.09 [95% CI, 1.02-1.16] for adequacy) and to the FNA needle (RR, 1.09 [95% CI, 1.01-1.19] for accuracy and 1.03 [95% CI, 1.01-1.07] for adequacy). Other comparisons did not achieve statistical significance. As a consequence, Franseen (surface under the cumulative ranking score, .89 for accuracy and .94 for adequacy) and Fork-tip needles (surface under the cumulative ranking score, .76 for accuracy and .73 for adequacy) ranked as the 2 highest-performing FNB needles. When considering different needle sizes, 25-gauge Franseen and 25-gauge Fork-tip needles were not superior to 22-gauge reverse-bevel needles (RR, 1.18 [95% CI, .96-1.46] and 1.04 [95% CI, .62-1.52]). None of the tested needles was significantly superior to the other FNB devices or to FNA needles when rapid onsite cytologic evaluation was available.

CONCLUSIONS

Franseen and Fork-tip needles, particularly 22-gauge size, showed the highest performance for tissue sampling of pancreatic masses, with low confidence in estimates.

Endoscopic ultrasound guided interventions in the management of pancreatic cancer

There has been a growing interest in developing endoscopic ultrasound (EUS)-guided interventions for pancreatic cancer, some of which have become standard of care. There are two main factors that drive these advancements to facilitate treatment of patients with pancreatic cancer, ranging from direct locoregional therapy to palliation of symptoms related to inoperable pancreatic cancer. Firstly, an upper EUS has the capability to access the entire pancreas–lesions in the pancreatic head and uncinate process can be accessed from the duodenum, and lesions in the pancreatic body and tail can be accessed from the stomach. Secondly, there has been a robust development of devices that allow through-the-needle interventions, such as placement of fiducial markers, brachytherapy, intratumoral injection, gastroenterostomy creation, and ablation. While these techniques are rapidly emerging, data from a multicenter randomized controlled trial for some procedures are awaited prior to their adoption in clinical settings.

Endoscopic ultrasound-guided side-fenestrated needle biopsy sampling is sensitive for pancreatic neuroendocrine tumors but inadequate for tumor grading: a prospective study

Accurate pretreatment grading of pancreatic neuroendocrine tumors (PanNETs) is important to guide patient management. We aimed to evaluate endoscopic ultrasound-guided fine needle biopsy sampling (EUS-FNB) for the preoperative diagnosis and grading of PanNETs. In a tertiary-center setting, patients with suspected PanNETs were prospectively subjected to 22-gauge, reverse-bevel EUS-FNB. The EUS-FNB samples (Ki-67_EUS) and corresponding surgical specimens (Ki-67_SURG) were analyzed with Ki-67 indexing and thereafter tumor grading, (GRADE_EUS) and (GRADE_SURG) respectively. In total 52 PanNET-patients [median age: 66 years; females: 25/52; surgical resection 22/52 (42%)] were included. EUS-FNB was diagnostic in 44/52 (85%). In 42 available FNB-slides, the median neoplastic cell count was 1034 (IQR: 504-3667) with 32/42 (76%), 22/42 (52%), and 14/42 (33%) cases exceeding 500, 1000, and 2000 neoplastic cells respectively. Ki-67_SURG was significantly higher compared to Ki-67_EUS with a moderate correlation comparing Ki-67_EUS and Ki-67_SURG (Pearson r = 0.60, r² = 0.36, p = 0.011). The GRADE_EUS had a weak level of agreement (κ = 0.08) compared with GRADE_SURG. Only 2/12 (17%) G2-tumors were correctly graded in EUS-FNB-samples. EUS-guided fine needle biopsy sampling is sensitive for preoperative diagnosis of PanNET but biopsy quality is relatively poor. Therefore, the approach seems suboptimal for pretreatment grading of PanNET.

Endoscopic ultrasonography‐guided tissue acquisition for small solid pancreatic lesions: Does the size matter?

Endoscopic ultrasonography‐guided tissue acquisition (EUS‐TA) is now an established technique to obtain the pathological diagnosis of solid pancreatic lesions (SPLs), but the diagnosis of small SPLS by EUS‐TA can still be difficult. We conducted a literature review and a meta‐analysis on the diagnostic yield of EUS‐TA according to the tumor size. In a meta‐analysis of 33 studies with 6883 cases, a pooled odds ratio (OR) of sensitivity was significantly higher in SPLs of >20 mm (OR 1.64, p = 0.02) and in SPLs of >10 mm (OR 3.05, p = 0.01), but not in SPLs of >30 mm (OR 1.18, p = 0.46). The meta‐analysis of accuracy also showed a similar trend: OR of 1.59 in SPLs of >20 mm (p < 0.01) and OR of 3.27 in SPLs of >10 mm (p < 0.01) and OR of 1.03 in SPLs of >30 mm (p = 0.87). The use of a 25‐gauge needle tended to improve sensitivity in small SPLs, though not statistically significant: OR of 1.25 and 2.82 in studies with and without a 25‐gauge needle (p = 0.08). The use of fine needle biopsy needles, slow pull method, and rapid on‐site evaluation did not significantly improve sensitivity in small SPLs. EUS‐TA for small SPLs, especially neuroendocrine neoplasms, is reported to have a high risk of adverse events. In summary, the diagnostic yield and safety of EUS‐TA for small (<20 mm) SPLs still needs improvement, and the best needle and technique for small SPLs should be further investigated.

Concordance of the histological diagnosis of type 1 autoimmune pancreatitis and its distinction from pancreatic ductal adenocarcinoma with endoscopic ultrasound-guided fine needle biopsy specimens: an interobserver agreement study

The histological diagnosis of type 1 autoimmune pancreatitis (AIP) based on the findings obtained by an endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) is feasible, but the diagnostic consistency of this method has not been confirmed. We determined the interobserver agreement among 20 pathologists regarding the diagnosis of type 1 AIP, including the distinction from pancreatic ductal adenocarcinoma (PDAC) using large tissue samples obtained by EUS-FNB. After guidance for diagnosing AIP with biopsy tissues was provided, a round 2 was performed. The median sensitivity and specificity for diagnosing PDAC vs. non-neoplastic diseases were 95.2% and 100%, respectively. In groups of specialists (n = 7) and the generalists (n = 13), Fleiss' к-values increased from 0.886 to 0.958 and from 0.750 to 0.816 in round 2. The concordance was fair or moderate for obliterative phlebitis and storiform fibrosis but slight for ductal lesion of type 1 AIP. Discordant results were due to ambiguous findings and biopsy tissue limitations. Among the specialists, the ratio of cases with perfect agreement regarding the presence of storiform fibrosis increased in round 2, but agreement regarding obliterative phlebitis or ductal lesions was not improved. Although the histological definite diagnosis of type 1 AIP was achieved by most observers in > 60% of the cases, the confidence levels varied. Because some ambiguities exist, the histological diagnostic levels based on the diagnostic criteria of type 1 AIP should not be taken for granted. Guidance is effective for improving accurate PDAC diagnoses (notably by recognizing acinar-ductal metaplasia) and for evaluating storiform fibrosis.

Randomized trial comparing the 25G and 22G Franseen needles in endoscopic ultrasound-guided tissue acquisition from solid pancreatic masses for adequate histological assessment

BACKGROUND

The effects of the Franseen needle size in endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) of solid pancreatic masses remain unclear. This study aimed to compare 25G and 22G Franseen needles in terms of adequate tissue acquisition from solid pancreatic masses.

METHODS

In this single-center, crossover, randomized noninferiority trial, eligible patients underwent EUS-FNB with both 25G and 22G Franseen needles in a randomized order between November 2018 and August 2020. Tissue specimens from each pass were separately evaluated based on the cellularity scoring system. The primary outcome was the proportion of acquired specimens allowing adequate histological assessment (cellularity score ≥3). A -15% noninferiority margin was assumed.

RESULTS

Data from 88 patients were analyzed, which showed malignant and benign lesions in 84 (95.5%) and four (4.5%) patients, respectively. Of the 88 specimens, 62 (70.5%) and 69 (78.4%) acquired using 25G and 22G needles, respectively, allowed adequate histological assessment. The adjusted proportion difference was -6.6% (95% confidence interval -8.8% to -4.5%), indicating noninferiority of the 25G Franseen needle (P < 0.001). The diagnostic accuracies of the 25G and 22G needles were 86.4% and 89.8%, respectively, with no significant difference (P = 0.180). Adverse events occurred in one patient.

CONCLUSIONS

The 25G Franseen needle showed a noninferior adequate tissue acquisition and similar diagnostic performance compared to that of the 22G Franseen needle. However, a 15% noninferiority margin was high for clinical use; thus, further consideration is needed (Clinical Trial Registry no. UMIN000034596).

Endoscopic ultrasound-guided fine-needle biopsy histology with a 22-gauge Franseen needle and fine-needle aspiration liquid-based cytology with a conventional 25-gauge needle provide comparable diagnostic accuracy in solid pancreatic lesions

Background and Aim

Fine‐needle biopsy (FNB) needles obtain more core samples and support the shift from cytologic to histologic evaluation; however, recent studies have proposed a superior diagnostic potential for liquid‐based cytology (LBC). This study compared the diagnostic ability of endoscopic ultrasound (EUS)‐guided FNB histology with a 22‐gauge Franseen needle (22G‐FNB‐H) and fine‐needle aspiration (FNA) LBC with a conventional 25‐gauge needle (25G‐FNA‐LBC).

Methods

We analyzed 46 patients who underwent both 22G‐FNB‐H and 25G‐FNA‐LBC in the same lesion during the same endoscopic procedure. This study evaluated the diagnostic ability of each needle, diagnostic concordance between needles, and incremental diagnostic effect of both needles compared to using each needle alone.

Results

The agreement rate for malignancy between both techniques was 93.5% (kappa value = 0.82). There was no significant difference in the diagnostic ability of both methods. 22G‐FNB‐H and 25G‐FNA‐LBC provided an incremental diagnostic accuracy in two (4.3%) cases and one (2.2%) case, respectively.

Conclusion

Our study demonstrated that the diagnostic accuracy of 25G‐FNA‐LBC and 22G‐FNA‐H for solid pancreatic lesions were comparable. A conventional 25‐gauge needle that punctures lesions with ease can be used in difficult cases and according to the skill of the endoscopist.

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.

Effectiveness of introducing a 20-gauge core biopsy needle with a core trap in EUS-FNA/B for diagnosing pancreatic cancer

Background

Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/B) is a standard method for pathological diagnosis of pancreatic solid lesions. The EchoTip ProCore 20G® (PC20), a 20-gauge biopsy needle with a forward-bevel core trap, has been available in Japan since 2015.

Methods

We compared the efficacy of the PC20 with that of the EchoTip ProCore 22G® (PC22) and Acquire 22G® (AC22) in EUS-FNA/B for diagnosing pancreatic cancer. This retrospective study included 191 patients with pancreatic cancer who underwent EUS-FNA/B using the PC20, PC22, or AC22 at our facility from April 2013 to October 2019. We investigated the patients’ clinical characteristics and the diagnostic accuracy and safety of each needle.

Results

A sufficient stroke length of puncture was secured in all patients. The maximum length under EUS was shorter with the AC22 (22.1 ± 2.2 mm) than PC20 (30.6 ± 0.7 mm, p < 0.01) and PC22 (30.3 ± 0.8 mm, p < 0.01). The histological accuracy was 96.4% with the PC20 but only 58.8% with the PC22 (adjusted p (p-adj) < 0.0001) and 75.0% with the AC22 (p-adj = 0.06). The diagnostic accuracy of the combination of histology and cytology was 96.4% with the PC20, while it was 72.1% with the PC22 (p-adj < 0.0001) and 91.7% with the AC22 (p-adj > 0.99). One patient (0.9%) in the PC20 group developed mild pancreatitis, but no adverse events occurred with the other needles.

Conclusions

The PC20 showed better diagnostic capability than the PC22. The diagnostic efficacy was similar between the PC20 and AC22. The high histological accuracy of the PC20 could be advantageous for lesions in which histological assessment is critical.

Utility of endoscopic ultrasound-guided fine-needle biopsy in the diagnosis of type 1 autoimmune pancreatitis

Background and study aims  Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) performs poorly in the histological diagnosis of type 1 autoimmune pancreatitis (AIP). The aim of this study was to assess the performance of fine-needle biopsy (FNB) comparing reverse bevel (RB) and fork-tip (FT) needles. Patients and methods  A retrospective study of prospectively maintained databases was performed. Patients with a final diagnosis of type 1 AIP who underwent EUS-FNB during diagnostic workup were included. Pathology reports were reviewed and classified as per international consensus diagnostic criteria (ICDC). The Primary outcome was EUS-FNB sensitivity in diagnosing type 1 AIP. Results  Between March 2011 and December 2018, 24 patients with a final diagnosis of type 1 AIP underwent FNB. Six patients underwent biopsy with the RB needle and 18 with the FT needle. Mean age (± SD) 62.2 (± 11.4), 17 (70.8 %) male. No RB samples were diagnostic compared to 14 (78 %) FT; P  = 0.001; of which 13 (72 %) were level 1. In eight (44 %) of FT cases a diagnosis was not possible without histology. Initial biopsy was diagnostic in five (62.5 %) of these cases. Including repeat biopsy, seven (87 %) had a diagnosis made by FT needle. Obliterative phlebitis (44 %) was the least frequently identified pathological feature and immunoglobulin (IgG)4 + plasma cells > 10 per high power field (78 %) the most common. Conclusion  The FT needle demonstrated good performance for diagnosing type 1 AIP. The results support the preferential use of this core biopsy needle for EUS pancreatic tissue sampling.

RNA Extraction from Endoscopic Ultrasound-Acquired Tissue of Pancreatic Cancer Is Feasible and Allows Investigation of Molecular Features

Transcriptome analyses allow the distinguishing of pancreatic ductal adenocarcinoma (PDAC) subtypes, exhibiting different prognoses and chemotherapy responses. However, RNA extraction from pancreatic tissue is cumbersome and has been performed mainly from surgical samples, which are representative of < 20% of cases. The majority of PDAC patients undergo endoscopic ultrasound (EUS)-guided tissue acquisition (EUS-TA), but RNA has been rarely extracted from EUS-TA with scanty results. Herein, we aimed to determine the best conditions for RNA extraction and analysis from PDAC EUS-TA samples in order to carry out molecular analyses. PDAC cases underwent diagnostic EUS-TA, with needles being a 25G fine needle aspiration (FNA) in all patients and then either a 20G lateral core-trap fine needle biopsy (FNB) or a 25G Franseen FNB; the conservation methods were either snap freezing, RNALater or Trizol. RNA concentration and quality (RNA integrity index; RIN) were analyzed and a panel of genes was investigated for tissue contamination and markers of molecular subtype and aggressivity through qRT-PCR. Seventy-four samples from 37 patients were collected. The median RNA concentration was significantly higher in Trizol samples (10.33 ng/uL) compared with snap frozen (0.64 ng/uL; p < 0.0001) and RNALater (0.19 ng/uL; p < 0.0001). The RIN was similar between Trizol (5.15) and snap frozen samples (5.85), while for both methods it was higher compared with RNALater (2.7). Among the needles, no substantial difference was seen in terms of RNA concentration and quality. qRT-PCR analyses revealed that samples from all needles were suitable for the detection of PDAC subtype markers (GATA6 and ZEB1) and splice variants associated with mutational status (GAP17) as well as for the detection of contaminating tissue around PDAC cells. This is the first study that specifically investigates the best methodology for RNA extraction from EUS-TA. A higher amount of good quality RNA is obtainable with conservation in Trizol with a clear superiority of neither FNA nor FNB needles. RNA samples from EUS-TA are suitable for transcriptome analysis including the investigation of molecular subtype and splice variants expression.