Comparison of 22-gauge aspiration needle with 22-gauge biopsy needle in endoscopic ultrasonography-guided subepithelial tumor sampling

Diagnostic yield of endoscopic and EUS-guided biopsy techniques in subepithelial lesions of the upper GI tract: a systematic review

BACKGROUND AND AIMS

Obtaining adequate tissue samples in subepithelial lesions (SELs) remains challenging. Several biopsy techniques are available, but a systematic review including all available techniques to obtain a histologic diagnosis of SEL is lacking. The aim of this study was to evaluate the diagnostic yield and adverse event rates of endoscopic biopsies, EUS-guided FNA (EUS-FNA), EUS-guided fine-needle biopsy (FNB) (EUS-FNB), and mucosal incision-assisted biopsy (MIAB) for SELs in the upper GI tract.

METHODS

A search strategy in multiple databases was performed. The primary outcome was diagnostic yield, defined as the percentage of procedures in which histology was obtained and resulted in a definitive histopathologic diagnosis. Secondary outcome measures included reported procedure-related adverse events, which were graded according to the AGREE (Adverse Events in Gastrointestinal Endoscopy) classification.

RESULTS

A total of 94 original articles were included. Studies were classified per endoscopic technique to obtain histopathology. This resulted in 8 included studies for endoscopic biopsy methods, 55 studies for EUS-FNA, 33 studies for EUS-FNB, and 26 studies for MIAB. Pooled rates for diagnostic yield were 40.6% (95% confidence interval [CI], 30.8-51.2) for endoscopic biopsy, 74.6% (95% CI, 69.9-78.7) for EUS-FNA, 84.2% (95% CI, 80.7-87.2) for EUS-FNB, and 88.2% (95% CI, 84.7-91.1) for MIAB. Reported procedure-related adverse events graded AGREE II or higher were 2.8% to 3.9% for endoscopic biopsies, 1.0% to 4.5% for EUS-FNA, .9% to 7.7% for EUS-FNB, and 1.9% to 7.9% for MIAB.

CONCLUSIONS

Based on the available evidence, MIAB and EUS-FNB seem to be most effective in terms of achieving a high diagnostic yield, with similar rates of adverse events.

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.

Comparison of 19G FNA Versus 22G FNB Needles for Endoscopic Ultrasound-Guided Fine-Needle Sampling of Subepithelial Tumors: Is Bigger Better?

OBJECTIVES

To compare the diagnostic efficiency of 19G fine-needle aspiration (FNA) and 22G fine-needle biopsy (FNB) in endoscopic ultrasound (EUS)-guided sampling for subepithelial tumors (SETs).

METHODS

The data of patients with SETs who underwent 19G FNA or 22G FNB were reviewed retrospectively in two tertiary hospitals. Tissue cores were assessed by macroscopic on-site evaluation (MOSE). Cytological or histological diagnosis were classified as definite, suspect, or no diagnosis.

RESULTS

Seventy five patients (mean age: 55 years, 44 males) underwent 19G EUS-FNA (31) or 22G EUS-FNB (44). The overall diagnostic yield was 82.7%. The rate of definite cytological diagnoses was 9.7% (3/31) in 19G and 13.6% (6/44) in 22G group (x2  = 1.520, P = .468). In terms of MOSE, 19G needle, requiring only two punctures, achieved a higher good tissue core rate than 22G group (100.0% [31/31] versus 84.1% [37/44], x2  = 5.440, P = .020]). For histological diagnosis, the 19G group achieved higher definite rate than the 22G group, 93.6% (29/31) versus 65.9% (29/44) (x2  = 7.957, P = .019) on the first puncture, 90.3% (28/31) versus 63.6% (28/44) (x2  = 7.139, P = .028) on the second puncture, 96.8% (30/31) versus 70.5% (31/44) (x2  = 7.319, P = .026) on both the first and second punctures, and 96.8% (30/31) versus 72.7% (32/44) (x2  = 7.538, P = .023) on all three punctures.

CONCLUSIONS

The 19G EUS-FNA requires only two punctures to achieve better tissue core quality by MOSE and yields a higher rate of histological diagnosis than 22G ProCore needle for SETs. The bigger 19G FNA needle seems to play an important role in the evaluation of SETs.

Comparative diagnostic yield of different endoscopic techniques for tissue sampling of upper gastrointestinal subepithelial lesions: a network meta-analysis

BACKGROUND

There is limited evidence on the comparative diagnostic performance of endoscopic tissue sampling techniques for subepithelial lesions. We performed a systematic review with network meta-analysis to compare these techniques.

METHODS

A systematic literature review was conducted for randomized controlled trials (RCTs) comparing the sample adequacy and diagnostic accuracy of bite-on-bite biopsy, mucosal incision-assisted biopsy (MIAB), endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), and EUS-guided fine-needle biopsy (FNB). Results were expressed as relative risk (RR) and 95%CI.

RESULTS

Eight RCTs were identified. EUS-FNB was significantly superior to EUS-FNA in terms of sample adequacy (RR 1.20 [95%CI 1.05-1.45]), whereas none of the other techniques significantly outperformed EUS-FNA. Additionally, bite-on-bite biopsy was significantly inferior to EUS-FNB (RR 0.55 [95%CI 0.33-0.98]). Overall, EUS-FNB appeared to be the best technique (surface under cumulative ranking [SUCRA] score 0.90) followed by MIAB (SUCRA 0.83), whereas bite-on-bite biopsy showed the poorest performance. When considering lesions <20 mm, MIAB, but not EUS-FNB, showed significantly higher accuracy rates compared with EUS-FNA (RR 1.68 [95%CI 1.02-2.88]). Overall, MIAB ranked as the best intervention for lesions <20 mm (SUCRA score 0.86 for adequacy and 0.91 for accuracy), with EUS-FNB only slightly superior to EUS-FNA. When rapid on-site cytological evaluation (ROSE) was available, no difference between EUS-FNB, EUS-FNA, and MIAB was observed.

CONCLUSION

EUS-FNB and MIAB appeared to provide better performance, whereas bite-on-bite sampling was significantly inferior to the other techniques. MIAB seemed to be the best option for smaller lesions, whereas EUS-FNA remained competitive when ROSE was available.

Prevalence, natural progression, and clinical practices of upper gastrointestinal subepithelial lesions in Korea: a multicenter study

BACKGROUND/AIMS

This study aimed to evaluate the prevalence and natural progression of subepithelial lesions (SELs) in the upper gastrointestinal (UGI) tract.

METHODS

The medical records of patients with UGI SELs who underwent endoscopic screening at eight university hospitals between January and December 2010 were retrospectively investigated. The follow-up evaluations were performed until December 2016.

RESULTS

UGI SELs were found in 1,044 of the 65,233 participants screened (endoscopic prevalence, 1.60%; the total number of lesions, 1,062; mean age, 55.1±11.2 years; men, 53.6%). The median follow-up period was 48 (range, 8-74) months. SELs were most frequently found in the stomach (63.8%) and had a mean size of 9.9±6.1 mm. Endoscopic ultrasonography (EUS) was performed in 293 patients (28.1%). The most common lesions were leiomyomas, followed by gastrointestinal stromal tumors (GISTs), and ectopic pancreas. The proportions of SELs with malignant potential according to size were 3% (<1 cm), 22% (1-2 cm), 27% (2-3 cm), and 38% (≥3 cm). In gastric SELs larger than 1 cm, resections were performed in 20 patients because of an increase in size, of which 12 were found to be GISTs.

CONCLUSION

The prevalence of UGI SELs was 1.60%. Further, 23% of gastric SELs ≥1 cm were precancerous lesions, most followed by EUS and clinical decisions without initial pathological confirmation.

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.

Endobronchial ultrasound bronchoscopy Franseen fine needle biopsy tool versus standard fine needle aspiration needle: Impact on diagnosis and tissue adequacy

BACKGROUND

The Franseen fine needle biopsy tool (Acquire®, Boston Scientific, Boston, MA) may provide better quality specimens than current endobronchial ultrasound-transbronchial needle aspiration (EBUS-TNBA) needles. We performed a comparative retrospective study evaluating the diagnostic yield of the Franseen fine needle biopsy (FNB) versus standard fine needle aspiration (FNA) for benign lymphadenopathy and tissue acquisition for next generation sequencing (NGS) in non-small cell carcinoma (NSCLC).

METHODS

All EBUS-TBNA procedures performed between January 1st, 2019 to January 1st^, 2020 where both the FNB needle and the FNA needle were used were analyzed. All demographic, procedural, and diagnostic data were recorded. The median tumor surface area, tumor cellularity and adequacy for NGS was evaluated for NSCLC specimens.

RESULTS

A total of 69 target lesions in 66 patients were biopsied with both the FNB and FNA needles. The mean (SD) size of target biopsied was 1.8 cm (0.8); The most common stations were 7 (54%) and 4R (26%). The mean (SD) needle passes were 6 (2.2) and 4 (1.8) with FNA and FNB needles, respectively (p < 0.0001). Benign lymphadenopathy was diagnosed with FNA needle in 46% and in 82% with FNB (p < 0.0001). NGS tissue adequacy was 47% with FNA needle versus 76% with FNB (p = 0.02). Median tumor surface area and tumor cellularity were greater with FNB needle than FNA needle (80 mm² versus 9 mm², p = 0.002, and 81% versus 45%, p = 0.0004).

CONCLUSION

The FNB needle demonstrated higher diagnostic yield in benign lymphadenopathy and higher quality for NGS than standard FNA needle.

The role of endoscopic ultrasound-guided fine-needle aspiration/biopsy in the diagnosis of mediastinal lesions

Objective

Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) is an accurate technique for sampling the pancreas and mediastinum. The aim of this study was to determine the value of EUS-FNA/FNB in the diagnosis of mediastinal lesions.

Methods

Data from 107 patients who underwent EUS-FNA/FNB for mediastinal lesions were evaluated.

Results

The sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNA/FNB for mediastinal lesions were 92.00%, 100%, 100%, and 85%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNA for malignant mediastinal lesions were 92.00%, 100%, 100%, and 86.00%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNB for malignant mediastinal lesions were 92.00%, 100%, 100%, and 82.00%, respectively. Except for the discomfort caused by conventional gastroscopy, none of the patients had any complications, such as damage to surrounding large blood vessels or nerves.

Conclusion

EUS-FNA/FNB is an effective tool for diagnosing unknown mediastinal lesions, without any obvious complications.

ACG Clinical Guideline: Diagnosis and Management of Gastrointestinal Subepithelial Lesions

Subepithelial lesions (SEL) of the GI tract represent a mix of benign and potentially malignant entities including tumors, cysts, or extraluminal structures causing extrinsic compression of the gastrointestinal wall. SEL can occur anywhere along the GI tract and are frequently incidental findings encountered during endoscopy or cross-sectional imaging. This clinical guideline of the American College of Gastroenterology was developed using the Grading of Recommendations Assessment, Development, and Evaluation process and is intended to suggest preferable approaches to a typical patient with a SEL based on the currently available published literature. Among the recommendations, we suggest endoscopic ultrasound (EUS) with tissue acquisition to improve diagnostic accuracy in the identification of solid nonlipomatous SEL and EUS fine-needle biopsy alone or EUS fine-needle aspiration with rapid on-site evaluation sampling of solid SEL. There is insufficient evidence to recommend surveillance vs resection of gastric gastrointestinal stromal tumors (GIST) <2 cm in size. Owing to their malignant potential, we suggest resection of gastric GIST >2 cm and all nongastric GIST. When exercising clinical judgment, particularly when statements are conditional suggestions and/or treatments pose significant risks, health-care providers should incorporate this guideline with patient-specific preferences, medical comorbidities, and overall health status to arrive at a patient-centered approach.

Comparison of 22G Fork-Tip and Franseen Needles and Usefulness of Contrast-Enhanced Endoscopic Ultrasound for Diagnosis of Upper Gastrointestinal Subepithelial Lesions

Endoscopic ultrasound (EUS)-guided tissue acquisition (EUS-TA) is less accurate in obtaining samples from gastrointestinal subepithelial lesions (SELs) ≤2 cm than from pancreatic cancers. The present study compared the usefulness of 22G Fork-tip and Franseen needles for EUS-TA and assessed the ability of contrast-enhanced harmonic EUS (CH-EUS) to diagnose SELs ≤2 cm. Fifty-seven patients who underwent EUS-TA for SELs ≤2 cm were evaluated. The primary endpoint was to compare the rate of acquisition of sufficient samples by these two needles. Secondary endpoints included technical success rate, adverse events, numbers of needle passes, and diagnostic ability of CH-EUS for SELs. Of the 57 included patients, 23 and 34 underwent EUS-TA with Fork-tip and Franseen needles, respectively. Technical success rates were 100% with both needles and adverse events occurred in zero (0%) and one (2.9%) patient with Fork-tip and Franseen needles, respectively. The rate of adequate sample acquisition was significantly higher using Fork-tip than Franseen needles (96% vs. 74%; p = 0.038). The hyper- or iso-vascular pattern on CH-EUS correlated significantly with a diagnosis of gastrointestinal stromal tumor (p < 0.001). EUS-TA with Fork-tip needles were superior to EUS-TA with Franseen needles in acquiring sufficient samples and CH-EUS was also useful for the diagnosis of SELs ≤2 cm.

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.

Efficacy, Feasibility, and Safety of Endoscopic Ultrasound-guided Fine-needle Biopsy for the Diagnosis of Gastrointestinal Subepithelial Lesions: A Systematic Review and Meta-analysis

BACKGROUND

Endoscopic ultrasound (EUS) fine-needle biopsy (FNB) has become an efficient method for diagnosing gastrointestinal (GI) subepithelial lesions (SELs). However, recent guidelines have not regarded FNB as the primary strategy for diagnosing GI SELs. We performed this study to systematically measure the efficacy, feasibility, and safety of EUS-FNB in diagnosing GI SELs.

MATERIALS AND METHODS

Relevant studies were searched in PubMed and EMBASE and published after January 2015 were included. The overall rates of diagnostic yield, technical success, and adverse events were calculated as outcome measures. The Jadad scale and the Newcastle-Ottawa scale were used to evaluate the quality of the trials, funnel plots and Egger's test were used to measure publication bias, and sensitivity and subgroup analyses were performed to explore the variance of heterogeneity and sensitivity, respectively.

RESULTS

Sixteen studies analyzing 969 patients between 2015 and 2020 were included. Studies showed little change in sensitivity, and 13 were considered high quality. A certain degree of publication bias existed in the diagnostic accuracy rate. The overall rates of diagnostic yield, technical success, and adverse events were [85.69% (95% confidence interval (CI): 82.73-88.22, I2=41.8%), 98.83% (95% CI: 96.73-99.97, I2=54.3%), and 1.26% (95% CI: 0.35-2.54, I2=0.0%)]. No clinical influencing factors were identified in the subgroup analysis.

CONCLUSIONS

EUS-FNB is a promising technology with a relatively superior diagnostic yield, technical success, and security, which is an optimal option for the diagnosis of SELs.

Endoscopic management of subepithelial lesions including neuroendocrine neoplasms: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends endoscopic ultrasonography (EUS) as the best tool to characterize subepithelial lesion (SEL) features (size, location, originating layer, echogenicity, shape), but EUS alone is not able to distinguish among all types of SEL.Strong recommendation, moderate quality evidence. 2: ESGE suggests providing tissue diagnosis for all SELs with features suggestive of gastrointestinal stromal tumor (GIST) if they are of size > 20 mm, or have high risk stigmata, or require surgical resection or oncological treatment.Weak recommendation, very low quality evidence. 3: ESGE recommends EUS-guided fine-needle biopsy (EUS-FNB) or mucosal incision-assisted biopsy (MIAB) equally for tissue diagnosis of SELs ≥ 20 mm in size.Strong recommendation, moderate quality evidence. 4: ESGE recommends against surveillance of asymptomatic gastrointestinal (GI) tract leiomyomas, lipomas, heterotopic pancreas, granular cell tumors, schwannomas, and glomus tumors, if the diagnosis is clear.Strong recommendation, moderate quality evidence. 5: ESGE suggests surveillance of asymptomatic esophageal and gastric SELs without definite diagnosis, with esophagogastroduodenoscopy (EGD) at 3-6 months, and then at 2-3-year intervals for lesions < 10 mm in size, and at 1-2-year intervals for lesions 10-20 mm in size. For asymptomatic SELs > 20 mm in size that are not resected, ESGE suggests surveillance with EGD plus EUS at 6 months and then at 6-12-month intervals.Weak recommendation, very low quality evidence. 6: ESGE recommends endoscopic resection for type 1 gastric neuroendocrine neoplasms (g-NENs) if they grow larger than 10 mm. The choice of resection technique should depend on size, depth of invasion, and location in the stomach.Strong recommendation, low quality evidence. 7: ESGE suggests considering removal of histologically proven gastric GISTs smaller than 20 mm as an alternative to surveillance. The decision to resect should be discussed in a multidisciplinary meeting. The choice of technique should depend on size, location, and local expertise.Weak recommendation, very low quality evidence. 8: ESGE suggests that, to avoid unnecessary follow-up, endoscopic resection is an option for gastric SELs smaller than 20 mm and of unknown histology after failure of attempts to obtain diagnosis.Weak recommendation, very low quality evidence. 9: ESGE recommends basing the surveillance strategy on the type and completeness of resection. After curative resection of benign SELs no follow-up is advised, except for type 1 gastric NEN for which surveillance at 1-2 years is advised.Strong recommendation, low quality evidence. 10: For lower or upper GI NEN with a positive or indeterminate margin at resection, ESGE recommends repeating endoscopy at 3-6 months and another attempt at endoscopic resection in the case of residual disease.Strong recommendation, low quality evidence.

The Diagnosis of Small Gastrointestinal Subepithelial Lesions by Endoscopic Ultrasound-Guided Fine Needle Aspiration and Biopsy

Endoscopic ultrasonography (EUS) has been widely accepted in the diagnosis of all types of tumors, especially pancreatic tumors, lymph nodes, and subepithelial lesions (SELs). One reason is that the examination can provide a detailed observation, with tissue samples being immediately obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). Many SELs are detected incidentally during endoscopic examinations without symptoms. Most SELs are mesenchymal tumors originating from the fourth layer, such as gastrointestinal stromal tumors (GISTs), leiomyomas, and schwannomas. GISTs are potentially malignant. Surgical treatment is recommended for localized GISTs of ≥20 mm. However, the indications for the diagnosis and follow-up of GISTs of <20 mm in size are controversial. There are several reports on the rapid progression or metastasis of small GISTs. Therefore, it is important to determine whether a SEL is a GIST or not. The main diagnostic method is EUS-FNA. Recently, endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) using a new biopsy needle has been reported to obtain larger tissue samples. Additionally, various biopsy methods have been reported to have a high diagnostic rate for small GISTs. In local gastric SELs, regardless of the tumor size, EUS can be performed first; then, EUS-FNA/B or various biopsy methods can be used to obtain tissue samples for decision-making in relation to therapy and the follow-up period.

Retrospective analysis of the outcomes of endoscopic submucosal dissection for the diagnosis and treatment of subepithelial lesions in a center with high expertise

Background

Use of endoscopic submucosal dissection (ESD) for the diagnosis and treatment of subepithelial lesions (SELs) is limited in the West, and the best approach for these lesions is still debated. In this study we describe our experience regarding the usefulness, safety and outcomes of ESD for SELs.

Method

We performed a retrospective analysis of ESD in the diagnosis and treatment of SELs between November 2010 and February 2021.

Results

A total of 634 ESDs were reviewed. Fifty-five (9%) were performed in SELs, 6 in the esophagus, 34 in the stomach, and 15 in the rectum. ESD was technically successful in 53 lesions (96%). Most of them (82%) had previous endoscopic ultrasound evaluation, but only 20% had a histological diagnosis previous to the ESD. Neuroendocrine tumors, gastrointestinal stromal tumors, and granular cell tumors accounted for 38% of the procedures, with a 100% rate of en bloc resection and 65% of R0 resection; the main criterion for non-curative resection was a deep positive margin, and none of the patients treated with complementary surgery had lesions on the gastrointestinal wall. Most of the procedures (62%) were performed in lesions with very low malignant potential, providing the definitive diagnosis of SELs where the previous diagnostic workup was inconclusive. We had a total of 2 delayed bleedings and 1 perforation, all treated endoscopically.

Conclusion

Our real-life experience showed that ESD can be an effective and safe diagnostic tool for undetermined SELs, as well as an effective treatment for neoplastic SELs with malignant potential.

[Alternatives of histological material collection - When and how is histological confirmation by ultrasound (US), computer tomography (CT) or endosonography (EUS) useful?]

Histological classifications of tumorous lesions together with adequate staging are necessary for stage-appropriate and personalized therapies. The indications, technical possibilities, and limitations as well as potential complications of image-guided needle biopsy by ultrasound, computed tomography, and endosonography are described. Which procedure for which organ and which lesion?

Advancements in the Diagnosis of Gastric Subepithelial Tumors

A diagnosis of subepithelial tumors (SETs) is sometimes difficult due to the existence of overlying mucosa on the lesions, which hampers optical diagnosis by conventional endoscopy and tissue sampling with standard biopsy forceps. Imaging modalities, by using computed tomography and endoscopic ultrasonography (EUS) are mandatory to noninvasively collect the target's information and to opt candidates for further evaluation. Particularly, EUS is an indispensable diagnostic modality for assessing the lesions precisely and evaluating the possibility of malignancy. The diagnostic ability of EUS appears increased by the combined use of contrast-enhancement or elastography. Histology is the gold standard for obtaining the final diagnosis. Tissue sampling requires special techniques to break the mucosal barrier. Although EUS-guided fine-needle aspiration (EUS-FNA) is commonly applied, mucosal cutting biopsy and mucosal incision-assisted biopsy are comparable methods to definitively obtain tissues from the exposed surface of lesions and seem more useful than EUS-FNA for small SETs. Recent advancements in artificial intelligence (AI) have a potential to drastically change the diagnostic strategy for SETs. Development and establishment of noninvasive methods including AI-assisted diagnosis are expected to provide an alternative to invasive, histological diagnosis.

Endoscopic ultrasound fine needle aspiration vs fine needle biopsy for pancreatic masses, subepithelial lesions, and lymph nodes

Endoscopic ultrasound tissue acquisition, in the form of both fine needle aspiration (EUS-FNA) and fine needle biopsy (EUS-FNB), is utilized for pancreatic mass lesions, subepithelial lesions, and lymph node biopsy. Both procedures are safe and yield high diagnostic value. Despite its high diagnostic yield, EUS-FNA has potential limitations associated with cytological aspirations, including inability to determine histologic architecture, and a small quantitative sample for further immunohistochemical staining. EUS-FNB, with its larger core biopsy needle, was designed to overcome these potential limitations. However, it remains unclear which technique should be used and for which lesions. Comparative trials are plagued by heterogeneity at every stage of comparison; including variable needles used, and different definitions of endpoints, which therefore limit generalizability. Thus, we present a review of prospective trials, systematic reviews, and meta-analyses on studies examining EUS-FNA vs EUS-FNB. Prospective comparative trials of EUS-FNA vs EUS-FNB primarily focus on pancreatic mass lesions, and yield conflicting results in terms of demonstrating the superiority of one method. However, consistent among trials is the potential for diagnosis with fewer passes, and a larger quantity of sample achieved for next generation sequencing. With regard to subepithelial lesions and lymph node biopsy, fewer prospective trials exist, and larger prospective studies are necessary. Based on the available literature, we would recommend EUS-FNB for peri-hepatic lymph nodes.

Histopathological comparison of aspiration and biopsy needles in endoscopic ultrasound-guided tissue acquisition in patients with subepithelial lesions

BACKGROUND

Information on whether a fine-needle biopsy (FNB) needle can improve histopathological specimen quality or the amount of core tissue collected in the diagnosis of subepithelial lesions (SELs) remains insufficient. In this study, we aimed to compare the procedure outcomes and adequacy of histopathological specimens of fine-needle aspiration (FNA) and FNB needles in endoscopic ultrasound-guided tissue acquisition (EUS-TA) using sample isolation processing by stereomicroscopy (SIPS) in patients with SELs.

METHODS

We performed a retrospective comparison of SEL cases registered in two previously conducted prospective studies. Of 61 cases, we identified 56 cases of SELs that involved the muscularis propria layer. Of these, 27 patients who underwent EUS-TA using a 22-gauge FNA needle between July 2016 and December 2017, and 29 patients who underwent the procedure using a 22-gauge FNB needle between March 2018 and January 2019 were included in the FNA and FNB group, respectively.

RESULTS

Patient background characteristics did not differ between the groups. The technical success rate was 100% in both groups. The median adequacy score was significantly higher in the FNB group than in the FNA group (P < .01). The histological diagnosis showed no significant difference in the accuracy rate between the groups.

CONCLUSIONS

In EUS-TA using the SIPS procedure to target SELs derived from the muscularis propria layer, FNB needles collect more core tissues and significantly improve histopathological specimen quality compared with FNA needles. When combined with SIPS, a high tissue diagnosis rate may be obtained regardless of the type of puncture needle used.

Comparison of fine-needle aspiration and fine-needle biopsy devices for endoscopic ultrasound-guided sampling of solid lesions: a systemic review and meta-analysis

BACKGROUND

Endoscopic ultrasound (EUS)-guided tissue acquisition is extensively used, but the optimal sampling device is still a matter of debate. We performed meta-analyses on studies comparing fine-needle aspiration (FNA) with fine-needle biopsy (FNB) needles, and studies comparing different FNB needles.

METHODS

Online databases were searched for randomized controlled trials (RCTs) of at least 50 cases with a suspected solid pancreatic or nonpancreatic lesion that compared FNA with FNB needles. Outcome measures included diagnostic accuracy, adequacy, number of passes, presence of tissue cores, and adverse events. We also performed meta-regression analysis on the effect of FNB design on diagnostic accuracy. Quality was assessed using the QUADAS-2 tool.

RESULTS

18 RCTs comparing FNA with FNB needles were included. FNB provided a higher pooled diagnostic accuracy (87 % vs. 80 %; P = 0.02) and tissue core rate (80 % vs. 62 %; P = 0.002), and allowed diagnosis with fewer passes (P = 0.03), in both pancreatic and nonpancreatic lesions. A total of 93 studies were included comparing different FNB devices. Pooled diagnostic accuracy was higher for forward-facing bevel needles than for the reverse bevel needle. In this analysis, study quality was low and heterogeneity was high (I2  = 80 %).

CONCLUSION

FNB outperformed FNA when sampling pancreatic and nonpancreatic lesions. Forward-facing bevel FNB needles seemed to outperform the reverse bevel FNB needle, but the low quality of evidence prevents us from making strong recommendations on the optimal FNB design.

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.

Systematic Endoscopic Approach for Diagnosing Gastric Subepithelial Tumors

Subepithelial tumors (SETs) are commonly encountered during upper gastrointestinal endoscopy, especially during national gastric cancer screening programs in Korea. Although the majority of SETs are benign, endoscopists harbor concerns regarding whether a SET is benign or malignant because the diagnosis cannot be established on the basis of routine endoscopic biopsy findings. The differential diagnosis of SETs is important, beginning with meticulous endoscopic examination, including the evaluation of the location, macroscopic shape, color, surface characteristics, mobility, consistency, and size of the tumors. The yield of endoscopic biopsy increases with the use of the bite-on-bite technique for SETs without the rolling or tenting sign, with large openings, and with erosion or ulceration. In this review, a systematic approach for the diagnosis of gastric SETs during conventional endoscopy is introduced.

Diagnosis of Pancreatic Solid Lesions, Subepithelial Lesions, and Lymph Nodes Using Endoscopic Ultrasound

Currently, endoscopic ultrasound (EUS) has become widely accepted and has considerable advantages over computed tomography (CT) and other imaging modalities, given that it enables echostructure assessment in lesions with <1 cm diameter and permits high resolution imaging. EUS-guided tissue acquisition (EUS-TA) provides consistent results under ultrasound guidance and has been considered more effective compared to CT- or ultrasound-guided lesion biopsy. Moreover, complication rates, including pancreatitis and bleeding, have been extremely low, with <1% morbidity and mortality rates, thereby suggesting the exceptional overall safety of EUS-TA. The aggressive use of EUS for various lesions has been key in facilitating early diagnosis and therapy. This review summarizes the diagnostic ability of EUS for pancreatic solid lesions, subepithelial lesions, and lymph nodes where it is mainly used. EUS has played an important role in diagnosing these lesions and planning treatment strategies. Future developments in EUS imaging technology, such as producing images close to histopathological findings, are expected to further improve its diagnostic ability. Moreover, tissue acquisition via EUS is expected to be used for precision medicine, which facilitates the selection of an appropriate therapeutic agent by increasing the amount of tissue collected and improving genetic analysis.

Utility of endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) for diagnosing small subepithelial lesions (< 20 mm)

AIM

Subepithelial lesions (SELs) are defined as being located under the mucosa. Presently, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is commonly performed to diagnose SELs. With the development of new puncture needles, endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB), which allows for the acquisition of large tissue samples, has been proposed. However, studies on EUS-FNB of SELs measuring < 20 mm have not yielded satisfactory results. Therefore, we aimed to assess the performance and usefulness of EUS-FNB of SELs measuring less than < 20 mm.

METHODS

The present study included 62 patients who underwent EUS-FNA or EUS-FNB for SELs at our hospital between January 2015 and March 2019. EUS-FNA was performed using fine-needle aspiration needles, and EUS-FNB was performed using fine-needle biopsy needles. These needles, which come in different shapes and diameters, were compared in terms of their usefulness in performing procedures for SELs measuring ≥ 20 mm and those measuring < 20 mm.

RESULTS

For SELs measuring ≥ 20 mm, the use of needles with a large diameter, such as 19 or 20 G, resulted in significantly improved diagnostic rates. For SELs measuring < 20 mm, the use of FNB needles showed significantly improved diagnostic rates, regardless of the size of the puncture needles.

CONCLUSION

Even when SELs are less than 20 mm, they might have malignant potential, and histological diagnosis may be desirable in some cases. EUS-FNB has an advantage over EUS-FNA in the diagnosis of SELs measuring < 20 mm.

Enhancements of Loading Capacity and Moving Ability by Microstructures for Wireless Soft Robot Boats

Because of its promising applications in various fields such as in vivo drug treatment, in-pipe inspection, and so forth, there is an increasing interest on wireless soft robot boats taking advantages of their shape adaptability. The loading capacity and mobility, however, are always fundamental challenges to restrict their applications. In this study, a graphene-based soft robot boat, which could be programmable-driven by a remote near-infrared light, is proposed. Different microstructures underneath the boat are carefully designed and employed to improve both the loading capacity and the moving ability. It reveals that, compared to that without microstructures, the soft robot boat with square pillar arrays (120-160 μm of period, duty cycle, and aspect ratio at active Wenzel/Cassie transition point) could enhance the loading capacity by 12.75% and the moving velocity by 16.70%. For the robot boat with grating structures, a strong driving anisotropy is revealed, with an enhancement of 2.24% for the loading capacity and 34.65% for the driving response along the grating lines. A boat prototype with a self-weight of 6.05 g is finally developed and can achieve continuous navigation in a closed narrow space for in situ monitoring, which may find applications in the inspection of other narrow terrains (e.g., blood vessels).

An exclusive fine-needle biopsy approach to sampling solid lesions under EUS guidance: a prospective cohort study

Background

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is increasingly utilized to enhance the cytological yield of sampling solid lesions, but its superiority over existing fine-needle aspiration (FNA) platforms has not been clearly demonstrated. The aim of our study was to compare the diagnostic accuracy and procedural outcomes of FNB using a new Franseen-tip needle to that of a traditional FNA in sampling solid lesions under EUS guidance.

Methods

Consecutive patients with solid lesions referred for EUS-FNB sampling were included. Procedure-related outcomes were collected prospectively including patient demographics, number of passes performed, diagnostic sample adequacy, adverse events, and recovery time. The Acquire needle was used to sample all lesions in the study group. Consecutive EUS-FNA procedures performed to sample solid lesions using the Expect needle were utilized as controls.

Results

There were 180 patients undergoing EUS-FNB compared to 183 patients undergoing EUS-FNA procedures for solid-lesion sampling. The procedure time was significantly shorter in patients who underwent FNB compared to FNA (mean: 37.4 vs 44.9 minutes, P < 0.001). Significantly fewer passes were performed in the FNB cohort compared to the FNA group (mean: 2.9 vs 3.8, P < 0.001). The cytologic diagnostic yield was significantly higher in the FNB group compared to the FNA group (98.3% vs 90.2%, P = 0.003). No significant difference in the incidence of adverse events was observed between the FNB and FNA groups (1.1% vs 0.5%, P = 0.564).

Conclusions

An FNB-exclusive approach to sampling solid lesions under EUS guidance is safe and feasible, and may result in fewer overall passes, shorter procedure time, and improved diagnostic adequacy. FNB may replace FNA as the primary sampling modality of choice in all solid lesions.

Comparison of the reverse bevel versus Franseen type endoscopic ultrasound needle

BACKGROUND

Reverse bevel (RB) needle is widely used for endoscopic ultrasound fine needle biopsy (EUS-FNB). A 3-plane symmetrical needle with Franseen geometry (FG) has recently become available.

AIM

To compare the clinical efficacy of FG to that of RB needle.

METHODS

A retrospective cohort study of all adult patients who underwent EUS-FNB for solid and mixed lesions either with 22G RB needle or 22G FG needle between January 2016 and February 2019 was undertaken. All cytology slides were reviewed by an independent gastrointestinal cytopathologist blinded to the needle used and the initial cytology report. The primary and secondary outcomes were to assess the sample adequacy using Euro-cytology criteria and the number of cell clusters, respectively.

RESULTS

Two hundred and twenty six procedures were included in the study. RB needle was used in 128 procedures and FG needle in 98 procedures. The baseline characteristics of both groups were comparable. On multivariable analysis, FG needle (P = 0.02) and location of the lesion (P < 0.01) were independently associated with adequate tissue. Further, the use of FG needle (P = 0.04) and the size of the lesion (P = 0.02) were independently associated with acquisition of increased number of cell clusters.

CONCLUSION

FG needle is superior to RB needle in acquiring adequate tissue and attaining higher number of cell clusters for solid and mixed lesions.

Improved diagnostic yield of endoscopic ultrasound-fine needle biopsy with histology specimen processing

BACKGROUND

Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) has emerged as a safe, efficacious alternative to fine needle aspiration (FNA) for tissue acquisition. EUS-FNB is reported to have higher diagnostic yield while preserving specimen tissue architecture. However, data on the optimal method of EUS-FNB specimen processing is limited.

AIM

To evaluate EUS-FNB with specimen processing as histology vs EUS-FNA cytology with regards to diagnostic yield and specimen adequacy.

METHODS

All EUS-FNA and EUS-FNB performed at our institution from July 1, 2016, to January 31, 2018, were retrospectively analyzed. We collected data on demographics, EUS findings, pathology, clinical outcomes, and procedural complications in two periods, July 2016 through March 2017, and April 2017 through January 2018, with predominant use of FNB in the second data collection time period. FNA specimens were processed as cytology with cell block technique and reviewed by a cytopathologist; FNB specimens were fixed in formalin, processed for histopathologic analysis and immunohistochemical staining, and reviewed by an anatomic pathologist. Final diagnosis was based on surgical pathology when available, repeat biopsy or imaging, and length of clinical follow up.

RESULTS

One hundred six EUS-FNA and EUS-FNB procedures were performed. FNA alone was performed in 17 patients; in 56 patients, FNB alone was done; and in 33 patients, both FNA and FNB were performed. For all indications, diagnostic yield was 47.1% (8/17) in FNA alone cases, 85.7% (48/56) in FNB alone cases, and 84.8% (28/33) in cases where both FNA and FNB were performed (P = 0.0039). Specimens were adequate for pathologic evaluation in 52.9% (9/17) of FNA alone cases, in 89.3% (50/56) of FNB alone cases, and 84.8% (28/33) in cases where FNA with FNB were performed (P = 0.0049). Tissue could not be aspirated for cytology in 10.0% (5/50) of cases where FNA was done, while in 3.4% (3/89) of FNB cases, tissue could not be obtained for histology. In patients who underwent FNA with FNB, there was a statistically significant difference in both specimen adequacy (P = 0.0455) and diagnostic yield (P = 0.0455) between the FNA and FNB specimens (processed correspondingly as cytology or histology).

CONCLUSION

EUS-FNB has a higher diagnostic yield and specimen adequacy than EUS-FNA. In our experience, specimen processing as histology may have contributed to the overall increased diagnostic yield of EUS-FNB.

Advances in Interventional Endoscopic Ultrasound (EUS): A Technical Review

Endoscopic ultrasound (EUS) has become the therapeutic intervention of choice for multiple diseases and continues to evolve rapidly. Its increasing use has allowed the development and adaptation of multiple, revolutionary devices and tools. Currently, there is paucity of randomized clinical trials evaluating multiple EUS-guided interventions and the vast majority of published data is heterogenous. However, the available literature on EUS-guided therapeutic interventions continues to expand and demonstrate its safety, efficacy and cost effectiveness in carefully selected patients when performed by expert endosonographers. The future of interventional EUS appears to be bright!

Current Status of Needles in the Optimization of Endoscopic Ultrasound-Guided Procedures

Endoscopic ultrasound (EUS) is among the most important tools for the evaluation of gastrointestinal tumors and affected areas around the gastrointestinal tract. It enables the acquisition of material from abnormal lesions via the gastrointestinal wall for tissue confirmation via endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). EUS-FNA has played a vital role in oncological care and has become the standard method for tissue sampling. The choice of needle type is an important factor determining tissue acquisition and has been evaluated by many researchers. New needles are introduced into the market almost every year, and opinions vary regarding proper needle selection. While there are diverse opinions but no definitive recommendations about the use of one particular device, fine-needle biopsy needles may provide detailed information on a tissue’s architecture based on greater sample yields. This permits additional analyses, including genetic sequencing and phenotyping, thereby enabling the provision of more personalized treatment plans. Furthermore, other EUS-guided procedures have been developed, including interventional EUS and through-the-needle devices. Given the continued attempts to improve the diagnostic ability and therapeutic techniques, we review in detail the available types of puncture needles to provide guidance on the selection of the appropriate needle types.

EUS-guided fine-needle biopsy sampling versus FNA in the diagnosis of subepithelial lesions: a large multicenter study

BACKGROUND AND AIMS

Although conventional EUS-guided FNA (EUS-FNA) has previously been considered first-line for sampling subepithelial lesions (SELs), variable accuracy has resulted in increased use of fine-needle biopsy (FNB) sampling to improve diagnostic yield. The primary aim of this study was to compare FNA versus FNB sampling for the diagnosis of SELs.

METHODS

This was a multicenter, retrospective study to evaluate the outcomes of EUS-FNA and EUS-guided FNB sampling (EUS-FNB) of SELs over a 3-year period. Demographics, lesion characteristics, sensitivity, specificity, accuracy, number of needle passes, diagnostic adequacy of rapid on-site evaluation (ROSE), cell block accuracy, and adverse events were analyzed. Subgroup analyses were performed comparing FNA versus FNB sampling by location and diagnostic yield with or without ROSE. Multivariable logistic regression was also performed.

RESULTS

Two hundred twenty-nine patients with SELs (115 FNA and 114 FNB sampling) underwent EUS-guided sampling. Mean patient age was 60.86 ± 12.84 years. Most lesions were gastric in location (75.55%) and from the fourth layer (71.18%). Cell block for FNB sampling required fewer passes to achieve conclusive diagnosis (2.94 ± 1.09 vs 3.55 ± 1.55; P = .003). The number of passes was not different for ROSE adequacy (P = .167). Immunohistochemistry was more able to be successfully performed in more FNB sampling samples (69.30% vs 40.00%; P < .001). Overall, sensitivity and accuracy were superior for FNB sampling versus FNA (79.41% vs 51.92% [P = .001] and 88.03% vs 77.19% [P = .030], respectively). On subgroup analysis, sensitivity and accuracy of FNB sampling alone was superior to FNA + ROSE (79.03% vs 46.67% [P = .001] and 87.25% vs 68.00% [P = .024], respectively). There was no significant difference in diagnostic yield of FNB sampling alone versus FNB sampling + ROSE (P > .05). Multivariate analysis showed no predictors associated with accuracy. One minor adverse event was reported in the FNA group.

CONCLUSIONS

EUS-FNB was superior to EUS-FNA in the diagnosis of SELs. EUS-FNB was also superior to EUS-FNA alone and EUS-FNA + ROSE. These results suggest EUS-FNB should be considered a first-line modality and may suggest a reduced role for ROSE in the diagnosis of SELs. However, a large randomized controlled trial is required to confirm our findings.

Diagnosing Gastric Mesenchymal Tumors by Digital Endoscopic Ultrasonography Image Analysis

Gastric mesenchymal tumors (GMTs) are incidentally discovered in national gastric screening programs in Korea. Endoscopic ultrasonography (EUS) is the most useful diagnostic modality for evaluating GMTs. The differentiation of gastrointestinal stromal tumors from benign mesenchymal tumors, such as schwannomas or leiomyomas, is important to ensure appropriate clinical management. However, this is difficult and operator dependent because of the subjective interpretation of EUS images. Digital image analysis computes the distribution and spatial variation of pixels using texture analysis to extract useful data, enabling the objective analysis of EUS images and decreasing interobserver and intraobserver agreement in EUS image interpretation. This review aimed to summarize the usefulness and future of digital EUS image analysis for GMTs based on published reports and our experience.

EUS-guided 22-gauge fine needle biopsy versus single-incision with needle knife for the diagnosis of upper gastrointestinal subepithelial lesions: a randomized controlled trial

Background and study aims  EUS-FNA has suboptimal accuracy in diagnosing gastrointestinal subepithelial tumors (SETs). EUS-guided 22-gauge fine needle biopsy (EUS-FNB) and single-incision with needle knife (SINK) were proposed to increase accuracy of diagnosis. This study aimed to prospectively compare the diagnostic accuracy and safety of EUS-FNB with SINK in patients with upper gastrointestinal SETs. Patients and methods  All adult patients referred for EUS evaluation of upper gastrointestinal SETs ≥ 15 mm in size were eligible for inclusion. Patients were randomized to undergo EUS-FNB or SINK. Lesions were sampled with a 22-gauge reverse beveled core needle in the EUS-FNB group and by a conventional needle-knife sphincterotome and biopsy forceps in the SINK group. Patients were blinded to the technique used. The primary outcome was diagnostic accuracy. Secondary outcomes included adverse events, histological yield and procedure duration. Study enrollment was terminated early due to poor recruitment. Results  A total of 56 patients (31 male (55.37 %); mean age, 67.41 ± 12.70 years) were randomized to either EUS-FNB (n = 26) or SINK (n = 30). Technical success was 96.15 % and 96.66 %, respectively. The majority of lesions were gastrointestinal stromal tumors (51.78 %). No significant difference was found between EUS-FNB and SINK in terms of diagnostic accuracy for a malignant or benign disease (76 % vs. 89.28 %, respectively; P  = 0.278). The rate of adverse events (none severe) was also comparable (7.69 % vs. 10 %, respectively; P =  1.0) including two abdominal pain episodes in the EUS-FNB group compared to two delayed bleeding (one requiring hospitalization and radiologic embolization) and 1 abdominal pain in the SINK group. Conclusion  EUS-FNB and SINK are equally effective techniques for upper gastrointestinal SETs sampling. SINK can be associated with mild to moderate delayed bleeding.

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

Background and Objectives

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

Methods

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

Results

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

Conclusion

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

Comparison between fine-needle biopsy and fine-needle aspiration for EUS-guided sampling of subepithelial lesions: a meta-analysis

BACKGROUND AND AIMS

There is limited evidence on the diagnostic performance of EUS-guided fine-needle biopsy (FNB) sampling in patients with subepithelial lesions. The aim of this meta-analysis was to compare EUS-guided FNB sampling performance with FNA in patients with GI subepithelial lesions.

METHODS

A computerized bibliographic search on the main databases was performed through May 2019. The primary endpoint was sample adequacy. Secondary outcomes were diagnostic accuracy, histologic core procurement rate, and mean number of needle passes. Summary estimates were expressed in terms of odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Ten studies (including 6 randomized trials) with 669 patients were included. Pooled rates of adequate samples for FNB sampling were 94.9% (range, 92.3%-97.5%) and for FNA 80.6% (range, 71.4%-89.7%; OR, 2.54; 95% CI, 1.29-5.01; P = .007). When rapid on-site evaluation was available, no significant difference between the 2 techniques was observed. Optimal histologic core procurement rate was 89.7% (range, 84.5%-94.9%) with FNB sampling and 65% (range, 55.5%-74.6%) with FNA (OR, 3.27; 95% CI, 2.03-5.27; P < .0001). Diagnostic accuracy was significantly superior in patients undergoing FNB sampling (OR, 4.10; 95% CI, 2.48-6.79; P < .0001) with the need of a lower number of passes (mean difference, -.75; 95% CI, -1.20 to -.30; P = .001). Sensitivity analysis confirmed these findings in all subgroups tested. Very few adverse events were observed and did not impact on patient outcomes.

CONCLUSIONS

Our results speak clearly in favor of FNB sampling, which was found to outperform FNA in all diagnostic outcomes evaluated.

EUS and EUS-guided FNA/core biopsies in the evaluation of subepithelial lesions of the lower gastrointestinal tract: 10-year experience

Background and Objective:

The widespread use of colonoscopy has led to an increasing number of subepithelial lesions (SELs) being detected in the lower gastrointestinal (GI) tract. This study aimed to analyze the utility of EUS and its role in the management of lower GI SELs.

Patients and Methods:

Records of all patients who were referred for lower EUS evaluation of a SEL at a tertiary center between 2007 and 2018 were retrospectively reviewed after IRB approval. Data collection included patient/lesion characteristics, technical details of procedure, and pathology results.

Results:

A total of 47 patients underwent EUS examinations for the evaluation of 49 suspected SEL in the lower GI tract (2 patients had 2 SELs each). Out of the 49 suspected lesions, the most frequent location was in the rectum (30/49, 61.2%). EUS showed extraluminal compression in 2 cases (2/49, 4.1%) and intraluminal lesions were identified in 40 cases (40/49, 81.6%). In 7 patients (7/49, 14.3%), no lesion could be identified by EUS. Twenty (20/49, 40.8%) SELs were malignant or had malignant potential. Twenty-six EUS-guided fine-needle aspirations (FNAs) and 14 EUS-core biopsies were performed. EUS-FNA alone was able to correctly diagnose 15/26 (57.7%) of the lower SELs. When EUS-guided fine needle biopsies (FNB) were performed during the same procedure, the final diagnosis was confirmed in 21/26 (80.8%) cases. There was only one procedure-related complication caused by use of narcotics.

Conclusion:

EUS-guided FNA/FNB are feasible and safe techniques for assessing lower GI SELs and provide valuable information regarding lesion characteristics and their malignant potential with high diagnostic accuracy.

Agreement on endoscopic ultrasonography-guided tissue specimens: Comparing a 20-G fine-needle biopsy to a 25-G fine-needle aspiration needle among academic and non-academic pathologists

BACKGROUND AND AIM

A recently carried out randomized controlled trial showed the benefit of a novel 20-G fine-needle biopsy (FNB) over a 25-G fine-needle aspiration (FNA) needle. The current study evaluated the reproducibility of these findings among expert academic and non-academic pathologists.

METHODS

This study was a side-study of the ASPRO (ASpiration versus PROcore) study. Five centers retrieved 74 (59%) consecutive FNB and 51 (41%) FNA samples from the ASPRO study according to randomization; 64 (51%) pancreatic and 61 (49%) lymph node specimens. Samples were re-reviewed by five expert academic and five non-academic pathologists and rated in terms of sample quality and diagnosis. Ratings were compared between needles, expert academic and non-academic pathologists, target lesions, and cytology versus histological specimens.

RESULTS

Besides a higher diagnostic accuracy, FNB also provided for a better agreement on diagnosing malignancy (ĸ = 0.59 vs ĸ = 0.76, P < 0.001) and classification according to Bethesda (ĸ = 0.45 vs ĸ = 0.61, P < 0.001). This equally applied for expert academic and non-academic pathologists and for pancreatic and lymph node specimens. Sample quality was also rated higher for FNB, but agreement ranged from poor (ĸ = 0.04) to fair (ĸ = 0.55). Histology provided better agreement than cytology, but only when a core specimen was obtained with FNB (P = 0.004 vs P = 0.432).

CONCLUSION

This study shows that the 20-G FNB outperforms the 25-G FNA needle in terms of diagnostic agreement, independent of the background and experience of the pathologist. This endorses use of the 20-G FNB needle in both expert and lower volume EUS centers.

Digital image analysis-based scoring system for endoscopic ultrasonography is useful in predicting gastrointestinal stromal tumors

BACKGROUND

When gastric mesenchymal tumors (GMTs) measuring 2-5 cm in size are found, whether to undergo further treatment or not is controversial. Endoscopic ultrasonography (EUS) is useful for the evaluation of malignant potential of GMTs, but has limitations, such as subjective interpretation of EUS images. Therefore, we aimed to develop a scoring system based on the digital image analysis of EUS images to predict gastrointestinal stromal tumors (GISTs).

METHODS

We included 103 patients with histopathologically proven GIST, leiomyoma or schwannoma on surgically resected specimen who underwent EUS examination between January 2007 and June 2018. After standardization of the EUS images, brightness values, including the mean (T_mean), indicative of echogenicity, and the standard deviation (T_SD), indicative of heterogeneity, in the tumors were analyzed.

RESULTS

Age, T_mean, and T_SD were significantly higher in GISTs than in non-GISTs. The sensitivity and specificity were almost optimized for differentiating GISTs from non-GISTs when the critical values of age, T_mean, and T_SD were 57.5 years, 67.0, and 25.6, respectively. A GIST-predicting scoring system was created by assigning 3 points for T_mean ≥ 67, 2 points for age ≥ 58 years, and 1 point for T_SD ≥ 26. When GMTs with 3 points or more were diagnosed as GISTs, the sensitivity, specificity, and accuracy of the scoring system were 86.5%, 75.9%, and 83.5%, respectively.

CONCLUSIONS

The scoring system based on the information of digital image analysis is useful in predicting GISTs in case of GMTs that are 2-5 cm in size.

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

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

Current Status of Endoscopic Ultrasonography in Gastrointestinal Subepithelial Tumors

Gastrointestinal subepithelial tumors (GSTs) are usually detected incidentally on endoscopic or radiologic examinations. In conventional endoscopy, a GST usually presents as a protuberant lesion with an intact mucosal surface. As the lesion is located beneath the mucosal layer of the gastrointestinal tract, conventional biopsy typically does not reveal the pathologic diagnosis. First, a GST should be differentiated from an extrinsic compression through the positional change of the patient during conventional endoscopic examination. In cases of GSTs originating from the gastrointestinal wall, endoscopic ultrasonography (EUS) can be beneficial for narrowing the differential diagnosis through delineation of echo findings and by determining the layer of origin. EUS findings can also help determine the management strategies for GSTs by making a differential diagnosis according to malignant potential.

Endoscopic ultrasonography in pancreatic diseases: advances in tissue acquisition

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

Fine-needle biopsy is superior to fine-needle aspiration of suspected gastrointestinal stromal tumors: a large multicenter study

Background and study aims  There are numerous studies published on the diagnostic yield of the new fine-needle biopsy (FNB) needles in pancreas masses. However, there are limited studies in suspected gastrointestinal stromal tumors (GIST lesions). The aim of this study was to evaluate the diagnostic yield of a new fork-tip FNB needle. Patients and methods  This was a multicenter retrospective study of consecutive patients from prospectively maintained databases comparing endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) versus endoscopic ultrasound-guided FNB (EUS-FNB) using the fork-tip needle. Outcomes measured were cytopathology yield (ability to obtain tissue for analysis of cytology), ability to analyze the tissue for immunohistochemistry (IHC yield), and diagnostic yield (ability to provide a definitive diagnosis). Results  A total of 147 patients were included in the study of which 101 underwent EUS-FNB and 46 patients underwent EUS-FNA. Median lesion size in each group was similar (21 mm vs 25 mm, P  = 0.25). Cytopathology yield, IHC yield, and diagnostic yield were 92 % vs 46 % ( P  = 0.001), 89 % vs 41 % ( P  = 0.001), and 89 % vs 37 % ( P  = 0.001) between the FNB and FNA groups, respectively. Median number of passes was the same between the two groups at 3.5. Conclusion  EUS-FNB is superior to EUS-FNA for diagnostic yield of suspected GIST lesions. This should be confirmed with a prospective study.

Noninvasive prediction model for diagnosing gastrointestinal stromal tumors using contrast-enhanced harmonic endoscopic ultrasound

BACKGROUND & AIMS

Subepithelial tumors (SETs) are difficult to diagnose accurately without invasive pathological confirmation. We created a noninvasive prediction model for diagnosing gastrointestinal stromal tumors (GISTs) using contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS).

METHODS

We retrospectively reviewed 176 patients who underwent CEH-EUS from October 2011 to August 2017. Seventy patients with a diagnosis of GIST (n = 37) or leiomyoma (n = 33) were included. The long-to-short axis ratio (LSR) and enhancement patterns (vascularity, diffuse enhancement) on CEH-EUS were assessed. Logistic regression and classification and regression tree (CART) analyses were performed.

RESULTS

The mean age of all patients was 54.9 ± 13.68 years. The GIST group showed significantly higher rates of positive vascularity (81.1% vs. 15.2%, p < 0.001) and diffuse enhancement (51.4% vs. 15.2%, p = 0.001), and lower LSR (1.30 vs. 1.76, p < 0.001). In multivariate logistic regression, positive vascularity (odds ratio [OR] 27.765, 95% confidence interval [CI] 5.336-144.458) and low LSR (OR 18.940, 95% CI 3.623-99.007) were independent predictors of GIST. A noninvasive prediction model for GISTs was developed using the CART model, by allocating patients according to statistically significant variables.

CONCLUSIONS

The LSR and vascularity of SETs on CEH-EUS can be used as parameters for a noninvasive prediction model of GISTs. This model may be helpful in the early identification and treatment of GISTs.

Prospective comparative study of endoscopic ultrasonography-guided fine-needle biopsy and unroofing biopsy

BACKGROUND AND AIM

Adequate tissue acquisition is important in making treatment decisions for patients with upper gastrointestinal subepithelial tumors (SETs). This study aimed to compare the outcomes of endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) with those of the unroofing biopsy technique.

METHODS

This study was a single-center, prospective comparative study conducted at Severance Hospital, Yonsei University College of Medicine. A total of 39 patients with SETs ≥15 mm were enrolled between January 2016 and August 2017.

RESULTS

Of the 39 patients, 28 underwent biopsy with both techniques (4 underwent only unroofing and 7 underwent only EUS-FNB). Histological diagnosis was made with EUS-FNB in 64.3% and unroofing biopsy in 78.6% (p = 0.344), and immunohistochemical diagnosis was made with EUS-FNB in 46.4% and unroofing biopsy in 67.9% (p = 0.180). In the subgroup analysis (28 patients), there was no significant difference in diagnostic yield between the 2 methods The mean procedural time with EUS-FNB was shorter than that with unroofing biopsy (p < 0.001). The larger SET (≥ 20 mm) (p = 0.035) and satisfaction of procedure (p = 0.019) were positively associated with successful histological diagnosis by EUS-FNB.

CONCLUSIONS

There was no significant difference in the histological diagnostic yield for SETs between the EUS-FNB and unroofing biopsy techniques (CinicalTrials.gov. identifier NCT02646241).

Positive-contrast susceptibility imaging based on first-order primal-dual optimization

PURPOSE

To achieve faster reconstruction and better imaging quality of positive-contrast MRI based on the susceptibility mapping by incorporating a primal-dual (PD) formulation.

METHODS

The susceptibility-based positive contrast MR technique was applied to estimate arbitrary magnetic susceptibility distributions of the metallic devices using a kernel deconvolution algorithm with a regularized ℓ 1 minimization. The regularized positive-contrast inversion problem and its PD formulation were derived. The visualization of the positive contrast and convergence behavior of the PD algorithm were compared with those of the nonlinear conjugate gradient algorithm, fast iterative soft-thresholding algorithm, and alternating direction method of multipliers. These methods were tested and validated on computer simulations and phantom experiments.

RESULTS

The PD approach could provide a faster reconstruction time compared with other methods. Experimental results showed that the PD algorithm could achieve comparable or even better visualization and accuracy of the metallic interventional devices in positive-contrast imaging with different SNRs and orientations to the B₀ field.

CONCLUSION

A susceptibility-based positive-contrast imaging technique by PD algorithm was proposed. The PD approach has more superior performance than other algorithms in terms of reconstruction time and accuracy for imaging the metallic interventional devices.

Impact of endoscopic ultrasound-guided fine-needle biopsy on the diagnosis of subepithelial tumors: A propensity score-matching analysis

BACKGROUND AND AIM

Immunohistological evaluations are essential for diagnosing subepithelial tumors (SET). However, endoscopic ultrasound-guided sampling using fine-needle aspiration (FNA) needles is limited in its ability to procure core tissue for immunostaining. Fine-needle biopsy (FNB) needles may mitigate this limitation. The present study aimed to examine the efficacy of FNB needles for procuring samples that enable the diagnosis of SET.

METHODS

One hundred sixty patients were included in the study and separated into those whose samples were obtained using FNB needles (FNB group) and those whose samples were procured using FNA needles (FNA group). Groups were compared regarding the conclusive diagnosis rate and unwarranted resection rate. Propensity score matching was introduced to reduce selection bias.

RESULTS

Rates at which conclusive diagnoses were reached through adequate immunohistological evaluations were 82% and 60% in the FNB and FNA groups, respectively; this difference was significant (P = 0.013). Unwarranted resection rate was significantly lower in the FNB group (2%) than in the FNA group (14%; P = 0.032). Multivariate analyses showed that lesions ≤20 mm were a significant risk factor for lower conclusive diagnosis rates following the use of FNB needles (P = 0.017).

CONCLUSIONS

Fine-needle biopsy needles can be useful for obtaining samples that facilitate the diagnosis of SET and for avoiding unwarranted resections. However, FNB needles may be less advantageous for small SET.

Diagnostic Endoscopic Ultrasound: Technique, Current Status and Future Directions

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

A multicenter randomized trial comparing a 25-gauge EUS fine-needle aspiration device with a 20-gauge EUS fine-needle biopsy device

BACKGROUND AND AIMS

Several studies have compared EUS-guided FNA with fine-needle biopsy (FNB), but none have proven superiority. We performed a multicenter randomized controlled trial to compare the performance of a commonly used 25-gauge FNA needle with a newly designed 20-gauge FNB needle.

METHODS

Consecutive patients with a solid lesion were randomized in this international multicenter study between a 25-gauge FNA (EchoTip Ultra) or a 20-gauge FNB needle (ProCore). The primary endpoint was diagnostic accuracy for malignancy and the Bethesda classification (non-diagnostic, benign, atypical, malignant). Technical success, safety, and sample quality were also assessed. Multivariable and supplementary analyses were performed to adjust for confounders.

RESULTS

A total of 608 patients were allocated to FNA (n = 306) or FNB (n = 302); 312 pancreatic lesions (51%), 147 lymph nodes (24%), and 149 other lesions (25%). Technical success rate was 100% for the 25-gauge FNA and 99% for the 20-gauge FNB needle (P = .043), with no differences in adverse events. The 20-gauge FNB needle outperformed 25-gauge FNA in terms of histologic yield (77% vs 44%, P < .001), accuracy for malignancy (87% vs 78%, P = .002) and Bethesda classification (82% vs 72%, P = .002). This was robust when corrected for indication, lesion size, number of passes, and presence of an on-site pathologist (odds ratio, 3.53; 95% confidence interval, 1.55-8.56; P = .004), and did not differ among centers (P = .836).

CONCLUSION

The 20-gauge FNB needle outperformed the 25-gauge FNA needle in terms of histologic yield and diagnostic accuracy. This benefit was irrespective of the indication and was consistent among participating centers, supporting the general applicability of our findings. (Clinical trial registration number: NCT02167074.).