Diagnostic efficacy of endoscopic ultrasound-guided needle sampling for upper gastrointestinal subepithelial lesions: a meta-analysis. Surg Endosc. 2016;30:2431-2441. [PMID: 26310529 DOI: 10.1007/s00464-015-4494-1]

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.

Artificial Intelligence-Based Diagnosis of Gastric Mesenchymal Tumors Using Digital Endosonography Image Analysis

Background/Objectives: Artificial intelligence (AI)-assisted endoscopic ultrasonography (EUS) diagnostic tools have shown excellent performance in diagnosing gastric mesenchymal tumors. This study aimed to assess whether incorporating clinical and endoscopic factors into AI-assisted EUS classification models based on digital image analysis could improve the diagnostic performance of AI-assisted EUS diagnostic tools. Methods: We retrospectively analyzed the data of 464 patients who underwent both EUS and surgical resection of gastric mesenchymal tumors, including 294 gastrointestinal stromal tumors (GISTs), 52 leiomyomas, and 41 schwannomas. AI-assisted classification models for GISTs and non-GIST tumors were developed utilizing clinical and endoscopic factors and digital EUS image analysis. Results: Regarding the baseline EUS classification models, the area under the receiver operating characteristic (AUC) values of the logistic regression, decision tree, random forest, K-nearest neighbor (KNN), and support vector machine (SVM) models were 0.805, 0.673, 0.781, 0.740, and 0.791, respectively. Using the new classification models incorporating clinical and endoscopic factors into the baseline classification models, the AUC values of the logistic regression, decision tree, random forest, KNN, and SVM models increased to 0.853, 0.715, 0.896, 0.825, and 0.794, respectively. In particular, the random forest and KNN models exhibited significant improvement in performance in Delong's test (both p < 0.001). Conclusion: The diagnostic performance of the AI-assisted EUS classification models improved when clinical and endoscopic factors were incorporated. Our results provided direction for developing new AI-assisted EUS models for gastric mesenchymal tumors.

Endoscopic resection for esophageal gastrointestinal stromal tumors: a multi-center feasibility study

Background

Esophageal gastrointestinal stromal tumors (E-GISTs) are highly uncommon and have not been thoroughly examined.

Objectives

The objective of this multi-center study was to assess the viability of endoscopic resection (ER) in the treatment of E-GISTs and to explore its clinical implications.

Design

This was a multi-center retrospective study. Consecutive patients referred to the four participating centers.

Methods

E-GISTs among the consecutive subepithelial tumors (SETs) treated by ER methods were enrolled from April 2019 to August 2022. Clinicopathological, endoscopic, and follow-up data were collected and analyzed.

Results

A total of 23 patients with E-GISTs were included for analysis, accounting for 1.9% of all the esophageal SETs (1243 patients). The average size of the tumor lesions was 2.3 cm (range 1.0-4.0 cm). We observed that tumors larger than 2.0 cm were more likely to grow deeper, with a statistically significant difference (p < 0.001). End bloc resection was achieved in all 23 patients. The mean operation time was 53.6 min (range 25-111 min). One patient experienced significant intraoperative bleeding, which was promptly managed endoscopically without necessitating surgery. The average hospital stay was 4.5 days (range 3-8 days). The overall median follow-up period was 31 months (range 13-47 months). No tumor recurrence, residual tumor, distal metastasis, or death was observed during the follow-up period.

Conclusion

Based on our limited data, our study indicates that ER may be a feasible and effective option for treating esophageal GISTs measuring 4 cm or less. We suggest submucosal tunnel endoscopic resection as the preferred approach, as all E-GISTs in our study were situated in the muscularis propria layer. Additionally, tumors larger than 2 cm were more prone to deeper growth or extraluminal extension.

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.

Endoscopic full-thickness resection (EFTR) compared to submucosal tunnel endoscopic resection (STER) for treatment of gastric gastrointestinal stromal tumors

Background and study aims  Submucosal tunnel endoscopic resection (STER) is being increasingly performed for treatment of gastric gastrointestinal stromal tumor (GIST), while STER has been limited by close dissection within tunnel and risking breach of tumor capsule. Endoscopic full-thickness resection (EFTR) allows resection of GIST with margins to prevent recurrence. This study aimed to compare EFTR against STER for treatment of gastric GIST. Patients and methods  We retrospectively reviewed clinical outcomes of patients with gastric GIST who received either STER or EFTR. Patients with gastric GISTs < than 4 cm were included. Clinical outcomes including baseline demographics, perioperative and oncological outcomes were compared between the two groups. Results  From 2013 to 2019, 46 patients with gastric GISTs were treated with endoscopic resection, 26 received EFTR and 20 received STER. Most of the GISTs were in the proximal stomach. There was no difference in operative time (94.9 vs 84.9 mins; P  = 0.401), while endoscopic suturing was applied more for closure after EFTR ( P  < 0.0001). Patients after STER had earlier resumption of diet and shorter hospital stay while there was no difference in adverse event rate between two groups. The en-bloc resection rate for EFTR was significantly higher than for STER (100 % vs 80 %; P  = 0.029), while there was no difference in the local recurrence. Conclusions  This study demonstrated that although patients who received EFTR had longer hospital stays and slower resumption of diet compared to those who underwent STER, EFTR achieved a significantly higher rate of en-bloc resection compared to STER for treatment of gastric GIST.

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.

Updates in the Field of Submucosal Endoscopy

Submucosal endoscopy (third-space endoscopy) can be defined as an endoscopic procedure performed in the submucosal space. This procedure is novel and has been utilized for delivery to the submucosal space in a variety of gastrointestinal diseases, such as a tumor, achalasia, gastroparesis, and subepithelial tumors. The main submucosal endoscopy includes peroral endoscopic myotomy, gastric peroral endoscopic myotomy, Zenker peroral endoscopic myotomy, submucosal tunneling for endoscopic resection, and endoscopic submucosal tunnel dissection. Submucosal endoscopy has been used as a viable alternative to surgical techniques because it is minimally invasive in the treatment and diagnosis of gastrointestinal diseases and disorders. However, there is limited evidence to prove this. This article reviews the current applications and evidence regarding submucosal endoscopy while exploring the possible future clinical applications in this field. As our understanding of these procedures improves, the future of submucosal endoscopy could be promising in the fields of diagnostic and therapeutic endoscopy.

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.

Mucosal incision-assisted biopsy versus endoscopic ultrasound-assisted tissue acquisition for subepithelial lesions: a systematic review and meta-analysis

Background/Aims

Mucosal incision-assisted biopsy (MIAB) for tissue acquisition (TA) from subepithelial lesions (SELs) is emerging as an alternative to endoscopic ultrasound (EUS)-guided TA. Only a limited number of studies compared the diagnostic utility of MIAB and EUS for upper gastrointestinal (GI) SELs; therefore, we conducted this systematic review and meta-analysis.

Methods

A comprehensive literature search from January 2020 to January 2022 was performed to compare the diagnostic accuracy and safety of MIAB and EUS-guided TA for upper GI SELs.

Results

Seven studies were included in this meta-analysis. The pooled technical success rate (risk ratio [RR], 0.96; 95% confidence interval [CI], 0.89–1.04) and procedural time (mean difference=–4.53 seconds; 95% CI, –22.38 to 13.31] were comparable between both the groups. The overall chance of obtaining a positive diagnostic yield was lower with EUS than with MIAB for all lesions (RR, 0.83; 95% CI, 0.71–0.98) but comparable when using a fine-needle biopsy needle (RR, 0.93; 95% CI, 0.83–1.04). The positive diagnostic yield of MIAB was higher for lesions <20 mm (RR, 0.75; 95% CI, 0.63–0.89). Six studies reported no adverse events.

Conclusions

MIAB can be considered an effective alternative to EUS-guided TA for upper GI SELs without an increased risk of adverse events.

Comparison of diagnostic performances of slow-pull suction and standard suction in endoscopic ultrasound-guided fine needle biopsy for gastrointestinal subepithelial tumors

Background/Aims

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is integral to the diagnosis of gastrointestinal (GI) subepithelial tumors (SETs). The impact of different EUS-FNB tissue sampling techniques on specimen adequacy and diagnostic accuracy in SETs has not been fully evaluated. This study aimed to compare the diagnostic outcomes of slow-pull (SP) and standard suction (SS) in patients with GI SETs.

Methods

In this retrospective comparative study, 54 patients were enrolled. Medical records were reviewed for location and size of the target lesion, FNB needle type/size, technical order, specimen adequacy, diagnostic yield, and adverse events. The acquisition rate of adequate specimens and diagnostic accuracy were compared according to EUS-FNB techniques.

Results

The mean lesion size was 42.6±36.4 mm, and most patients were diagnosed with GI stromal tumor (75.9%). The overall diagnostic accuracies of the SP and SS techniques were 83.3% and 81.5%, respectively (p=0.800). The rates of obtaining adequate core tissue were 79.6% and 75.9%, respectively (p=0.799). No significant clinical factors affected the rate of obtaining adequate core tissue, including lesion location and size, FNB needle size, and final diagnosis.

Conclusions

SP and SS had comparable diagnostic accuracies and adequate core tissue acquisition for GI SETs via EUS-FNB.

Technical Performance, Overall Accuracy and Complications of EUS-Guided Interventional Procedures: A Dynamic Landscape

Endoscopic ultrasound (EUS) gained wide acceptance as the diagnostic and minimally invasive therapeutic approach for intra-luminal and extraluminal gastrointestinal, as well as various non-gastrointestinal lesions. Since its introduction, EUS has undergone substantial technological advances. This multi-centric study is a retrospective analysis of a prospectively maintained database of patients who underwent EUS for the evaluation of lesions located within the gastrointestinal tract and the proximal organs. It aimed to extensively assess in dynamic the dual-center EUS experience over the course of the past 20 years. Hence, we performed a population study and an overall assessment of the EUS procedures. The performance of EUS-FNA/FNB in diagnosing pancreatic neoplasms was evaluated. We also investigated the contribution of associating contrast-enhanced ultrasound imaging (CE-EUS) with EUS-FNA/FNB for differentiating solid pancreatic lesions or cystic pancreatic lesions. A total of 2935 patients undergoing EUS between 2002–2021 were included, out of which 1880 were diagnostic EUS and 1052 EUS-FNA/FNB (80% FNA and 20% FNB). Therapeutic procedures performed included endoscopic transmural drainage of pancreatic fluid collections, celiac plexus block and neurolysis, while diagnostic EUS-like CE-EUS (20%) and real-time elastography (12%) were also conducted. Most complications occurred during the first 7 days after EUS-FNA/FNB or pseudocyst drainage. EUS and the additional tools have high technical success rates and low rates of complications. The EUS methods are safe, cost effective and indispensable for the diagnostic or therapeutic management in gastroenterological everyday practice.

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.

Comparison between endoscopic ultrasound-guided fine-needle biopsy and bite-on-bite jumbo biopsy for sampling of subepithelial lesions

BACKGROUND AND AIMS

A direct comparison between endoscopic ultrasound (EUS) fine-needle biopsy (FNB) and current endoscopic biopsy techniques in patients with subepithelial lesions (SELs) is still lacking. Aim of this multicenter study was to compare the diagnostic performance and safety profile between EUS-FNB and bite-on-bite jumbo biopsy.

METHODS

Out of 416 patients undergoing endoscopic sampling of SELs between 2017 and 2021, after propensity score matching two groups were compared: 120 undergoing EUS-FNB and 120 sampled with bite-on-bite jumbo biopsy. Primary outcome was sample adequacy. Secondary outcomes were diagnostic accuracy, sensitivity, specificity, and adverse events.

RESULTS

Median age was 61 years and most patients were male in both groups. Final diagnosis was GIST in 65 patients (54.1%) in the EUS-FNB group and 62 patients in the bite-on-bite biopsy group (51.6%; p = 0.37). Sample adequacy was significantly higher in the EUS-FNB group as compared to the bite-on-bite biopsy group (94.1% versus 77.5%, p<0.001). EUS-FNB outperformed bite-on-bite biopsy also in terms of diagnostic accuracy (89.3% versus 67.1%, p<0.001) and sensitivity (89% vs 64.5%; p<0.001), whereas specificity was 100% in both groups (p = 0.89). These findings were confirmed in subgroup analysis according to SEL location, final diagnosis, and wall layers of the sampled SEL. Adverse event rate was 6.6% in the EUS-FNB group and 30% in the bite-on-bite biopsy group (p<0.001).

CONCLUSION

EUS-FNB outperforms bite-on-bite biopsy both in terms of diagnostic yield and safety profile.

Efficiency of an endoscopic resection strategy for management of submucosal tumors < 20 mm in the upper gastrointestinal tract

Background and study aims  The histologic diagnosis of submucosal tumors (SMTs) < 20 mm is challenging. Monitoring is the main option offered, but compliance is debatable. Endoscopic resection (ER) of malignant SMTs or those with an uncertain diagnosis is an alternative that has already been reported about and proposed in our center. The aims of this study were to confirm the safety of this resection strategy and to perform long-term follow-up of malignant SMTs after resection. Patients and methods  All patients who underwent ER for SMTs < 2 cm in a single center between 2007 and 2019 were included retrospectively. Patients were classified into two groups according to the need for postresection follow-up: benign SMTs (B-SMTs) and follow-up SMTs (FU-SMTs). Results  One hundred and one patients were included. The mean tumor size was 16.7 mm. In total, 92 of 101 SMTs had an uncertain diagnosis. Macroscopic resection was completed for 95 SMTs (93.1 %), with en bloc resection in 94 (92.1%). The morbidity rate was 3 %, with no mortality. A total of 84 of 101 SMTs (84 %) were B-SMTs and did not need monitoring, and 17 SMTs (19.7 %) were FU-SMTs (8 gastrointestinal stromal tumors, 6 neuroendocrine tumors, and 3 others). No relapse was reported in the FU-SMT group, with a median follow-up duration of 33 months [4-127] (61 months [17-127] for the gastrointestinal stroma tumor group). Conclusions  The study results suggest ER is a potentially reliable and effective strategy for upper gastrointestinal tract SMTs < 20 mm. Although the strategy needs further validation in advanced care units, it could eliminate the need for long-term monitoring, therefore targeting such follow-up efforts to patients with FU-SMTs.

Endoscopic Ultrasonography-guided Fine-needle Aspiration Cytology Combined with a Cell-block Method for Gastrointestinal Subepithelial Lesions

Objective The diagnostic accuracy of an endoscopic ultrasound-guided fine-needle aspiration cytology/biopsy combined with a cell-block method (FNA-CB) for gastrointestinal subepithelial lesions (GI-SELs) has not been fully studied. Methods A total of 109 patients (with 110 GI-SELs) were evaluated to clarify the rate of obtaining evaluable histology specimens using FNA-CB. In addition, we investigated the following: 1) the accuracy for determining the histology, 2) effects of the number of cell clusters obtained via FNA-CB, 3) correlation of the Ki67 labelling index (Ki67LI) of the gastrointestinal stromal tumor (GIST) lesions between FNA-CB and resected specimens, and 4) clinical courses for patients followed up after FNA-CB. Results Of the 110 GI-SELs for which FNA-CB was performed, 95 (86%) were able to be histologically evaluated using the first FNA-CB. For the 70 resected GI-SELs, the accuracy of FNA-CB to determine histology was 96%, remaining at 90% even when only a few cell clusters were obtained. The concordance rate of the risk-grouping of GIST (high-risk, Ki67LI ≥8; low-risk, <8) between FNA-CB and resected specimens was 84%. Of the 29 patients followed up after the first FNA-CB, 12 with benign GI-SELs determined using the first FNA-CB showed no obvious increases in their GI-SEL sizes. Conclusion Since FNA-CB can be used to determine the histology and reproductive activity of GI-SELs accurately, not only preoperative histological confirmation but also reliable information to determine clinical plans, such as follow-up without surgery or neoadjuvant chemotherapy, can be obtained.

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.

How to Approach Submucosal Lesions in the Gastrointestinal Tract: Different Ideas between China and USA

Between 2019 and 2020, the author Gao pursued advanced endoscopic training at the University of Mississippi Medical Center in the USA. She experienced certain different ideas between the East (China) and the West (USA) in terms of endoscopic approach to the submucosal tumors (SMTs) or lesions in the gastrointestinal (GI) tract. In the West (USA), when SMTs are found on gastroscopy, the main goal of endoscopists is to obtain a tissue diagnosis through endoscopic ultrasound-guided fine-needle aspiration or biopsy (EUS-FNA or FNB) or single incision needle-knife biopsy (SINK); if immunohistochemical tests confirmed the GISTs, the first-line treatment is local surgery, that is, diagnosis before treatment, whereas in China, SMTs will be completely resected with endoscopic technology for those with no lymph node metastasis or extremely low risk of lymph node metastasis. There may not be pathological tissue at first, that is, treatment before diagnosis.

Efficacy of the Franseen needle for diagnosing gastrointestinal submucosal lesions including small tumors

Background and Objectives:

Several studies have demonstrated that EUS-guided fine-needle biopsy (EUS-FNB) is useful for diagnosing gastrointestinal subepithelial lesions (GI SELs). However, there is limited evidence regarding the use of Franseen needles during EUS-FNB for patients with GI SELs. In addition, the optimal approach for diagnosing small SELs is unclear. This study aimed to evaluate whether EUS-FNB using a Franseen needle was effective for diagnosing GI SELs, including small lesions.

Methods:

Between January 2013 and January 2020, 150 consecutive patients with GI SELs underwent EUS-FNA/FNB to achieve a histological diagnosis. Eighty-six consecutive patients who underwent EUS-FNB using a Franseen needle were compared to 64 patients who underwent EUS-FNA using a conventional needle.

Results:

The diagnostic yield was significantly higher using a Franseen needle than using a conventional needle (85% vs. 75%, P = 0.006). Furthermore, in cases with SELs that were <20 mm, the diagnostic yield was significantly higher using a Franseen needle than using a conventional needle (81% vs. 45%; P = 0.003). Multivariate analysis revealed that obtaining a sufficient diagnostic sample was independently predicted by Franseen needle use (adjusted odds ratio: 2.8, 95% confidence interval: 1.2–6.3; P = 0.01) and tumor size of >20 mm (adjusted odds ratio: 3.4, 95% confidence interval: 1.4–8.2; P = 0.006).

Conclusion:

Even when attempting to diagnose small GI SELs, EUS-FNB using a Franseen needle appears to provide a more efficient acquisition of true histological core tissue than using a conventional needle.

Endoscopic ultrasound-guided sampling of gastrointestinal subepithelial lesions: just wet it

INTRODUCTION

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the main method for acquisition of tissue from gastrointestinal subepithelial lesions (SELs). Despite the development of new needles, diagnostic yield remains low. A new method of aspiration has been described, where the needle is filled with saline [wet-suction technique (WST)], with promising results in pancreatic lesions. This method has not been tested in SELs.

AIMS AND METHODS

Prospective single center study to assess the diagnostic yield of EUS-FNA+WST in the diagnosis of SELs, without the use of rapid on-site evaluation. In mesenchymal tumors, the diagnosis was considered positive only when immunohistochemistry could differentiate between gastrointestinal stromal tumor and leiomyoma.

RESULTS

Eighty-seven patients with SELs were included (55% male, mean age 66 years). Mean SEL size was 25 mm (min 10 mm, max 120 mm), mean number of passes was 3 (±0.8). A 22G needle was used in 72 patients (83%), 19G in 10 (12%) and 25G in 5 (6%). We obtained a conclusive cytopathological diagnosis in 74 cases (diagnostic yield of 85%) and immunohistochemistry was performed in 70 cases (81%). The most frequent diagnoses were gastrointestinal stromal tumor (n = 34, 37%), leiomyoma (n = 13, 15%) and metastases (n = 10, 11%).

CONCLUSION

Wet suction technique allowed an excellent diagnostic yield in the EUS-guided evaluation of SELs. We suggest that, after proper replication of these results, WST may become the first-line method in the management of these lesions.

EUS-Guided Biopsy with a Novel Puncture Biopsy Forceps Needle-Feasibility Study

Endoscopic ultrasound (EUS) with fine needle aspiration (FNA) or biopsy (FNB) to diagnose lesions in the gastrointestinal tract is common. Demand for histology sampling to identify treatment-specific targets is increasing. Various core biopsy FNB needles to obtain tissue for histology are currently available, however, with variable (37-97%) histology yields. In this multicenter study, we evaluated performance, safety, and user experience of a novel device (the puncture biopsy forceps (PBF) needle). Twenty-four procedures with the PBF needle were performed in 24 patients with a suspected pancreatic lesion (n = 10), subepithelial lesion (n = 10), lymph node (n = 3), or pararectal mass (n = 1). In 20/24 (83%) procedures, the PBF needle yielded sufficient material for interpretation (sample adequacy). In 17/24 (71%), a correct diagnosis was made with the material from the PBF needle (diagnostic accuracy). All participating endoscopists experienced a learning curve. (Per)procedural technical issues occurred in four cases (17%), but there were no adverse events. The PBF needle is a safe and potentially useful device to obtain an EUS-guided biopsy specimen. As the design of the PBF needle is different to core biopsy FNB needles, specific training will likely further improve the performance of the PBF needle. Furthermore, the design of the needle needs further improvement to make it more robust in clinical practice.

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.

Tunneled biopsy is an underutilised, simple, safe and efficient method for tissue acquisition from subepithelial tumours

BACKGROUND

Tissue acquisition from subepithelial lesions is often attempted by endoscopic ultrasound (EUS)-sampling as conventional endoscopic biopsy usually fails to reach deeper layers of the gastrointestinal wall.

AIM

To investigate the utilisation, safety and diagnostic yield of an intensified “bite-on-bite” tunnel biopsy technique.

METHODS

In this retrospective cohort study, all patients presenting with subepithelial masses in the upper gastrointestinal tract from March 2013 to July 2019 were included. Data were analysed for size and location of the subepithelial mass, use of intensified tunnel biopsy protocol (more than 10 double bite-on-bite biopsies) or superficial conventional biopsies, histology and imaging results, occurrence of readmission and adverse events after endoscopy.

RESULTS

Two hundred and twenty-nine patients with subepithelial lesions were included. Superficial conventional biopsies were taken in 117 patients and were diagnostic only in one lipoma (0.9 %). Tunnel biopsies taken in 112/229 (48.9%) patients were significantly more likely to provide histological diagnosis (53.6%; P < 0.001). For lesions ≥ 10mm the diagnostic yield of tunnel biopsies further increased to 41/67 (61.2%). No immediate or delayed complications were reported. Only 8 of the 51 endoscopists (15.7%) regularly attempted tunnel biopsies.

CONCLUSION

Tunnel biopsy is a simple, safe and efficient but underutilised diagnostic modality for tissue acquisition in subepithelial masses. It should be routinely attempted at the initial endoscopy.

Recent Progress and Challenges in the Diagnosis and Treatment of Gastrointestinal Stromal Tumors

Simple Summary

Gastrointestinal stromal tumors (GIST) are potentially malignant tumors and require evidence-based surgical and/or medical treatment. Laparoscopy has similar safety and prognostic outcomes to those of laparotomy and is currently a standard procedure for localized GISTs. However, surgery for gastric GISTs less than 2 cm may be re-evaluated due to the indolent nature of the GIST and other competing risks among GIST patients. A work-up with endoscopy and endoscopic ultrasonography as well as endoscopic or percutaneous biopsy is important for the preoperative diagnosis of GISTs. Medical treatment with tyrosine kinase inhibitors is the mainstay for recurrent/metastatic GISTs. The activity of an individual drug is well correlated with gene alterations, and, in the era of precision medicine, cancer genome profiling should be considered before medical treatment.

Abstract

Gastrointestinal stromal tumors (GISTs) are the most frequent malignant mesenchymal tumors in the gastrointestinal tract. The clinical incidence of GISTs is estimated 10/million/year; however, the true incidence is complicated by frequent findings of tiny GISTs, of which the natural history is unknown. The initial work-up with endoscopy and endoscopic ultrasonography plays important roles in the differential diagnosis of GISTs. Surgery is the only modality for the permanent cure of localized GISTs. In terms of safety and prognostic outcomes, laparoscopy is similar to laparotomy for GIST treatment, including tumors larger than 5 cm. GIST progression is driven by mutations in KIT or PDGFRA or by other rare gene alterations, all of which are mutually exclusive. Tyrosine kinase inhibitors (TKIs) are the standard therapy for metastatic/recurrent GISTs. Molecular alterations are the most reliable biomarkers for TKIs and for other drugs, such as NTRK inhibitors. The pathological and genetic diagnosis prior to treatment has been challenging; however, a newly developed endoscopic device may be useful for diagnosis. In the era of precision medicine, cancer genome profiling by targeted gene panel analysis may enable potential targeted therapy even for GISTs without KIT or PDGFRA mutations.

Effectiveness of EUS-Guided Fine-Needle Biopsy versus EUS-Guided Fine-Needle Aspiration: A Retrospective Analysis

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic tumors and subepithelial lesions (SEL) of the gastrointestinal tract are effective for histological diagnosis. There are also reports that tissue sampling is possible with a smaller number of punctures by EUS-guided fine-needle biopsy (EUS-FNB). In this study, we retrospectively compared the diagnostic abilities of EUS-FNA and EUS-FNB. We examined 130 patients who underwent EUS-FNA/EUS-FNB for pancreatic tumors and SEL from July 2018 to January 2021. None of the cases underwent rapid on-site evaluation. There were 94 and 36 cases in the EUS-FNA and EUS-FNB groups, respectively. The median tumor size in the EUS-FNB group was 30 mm, which was significantly larger than the EUS-FNA group (p = 0.02). In addition, transgastric puncture was significantly more common in the EUS-FNB group (p = 0.01). The EUS-FNA and EUS-FNB groups had a sensitivity of 82.9% and 91.7% and an accuracy rate of 85.1% and 91.7%, respectively. However, both procedures had a comparable diagnostic ability.

Indocyanine green-labeled dasatinib as a new fluorescent probe for molecular imaging of gastrointestinal stromal tumors

BACKGROUND AND AIM

It is difficult to differentiate gastrointestinal stromal tumors (GISTs) from other subepithelial lesions under gastrointestinal endoscopy. Because most GISTs express tyrosine kinase receptor c-KIT, fluorescence-labeled c-KIT-specific tyrosine kinase inhibitors seem to be useful agents for molecular imaging of GIST. We aimed to develop a near-infrared fluorescent imaging technology for GIST targeting c-KIT using the novel fluorescent probe indocyanine green-labeled dasatinib (ICG-dasatinib) and to investigate the antitumor effect of ICG-dasatinib on GIST cells.

METHODS

Indocyanine green-labeled dasatinib was synthesized by labeling linker-induced dasatinib with ICG derivative 3-indocyanine-green-acyl-1,3-thiazolidine-2-thione. Human GIST cell lines GIST-T1 and GIST-882M were incubated with ICG-dasatinib and observed by fluorescent microscopy. GIST cells were incubated with ICG-dasatinib, unlabeled dasatinib, or imatinib, and cell viabilities were evaluated. Subcutaneous GIST model mice or orthotopic GIST model rats were intravenously injected with ICG-dasatinib and observed using an IVIS Spectrum.

RESULTS

Strong fluorescent signals of ICG-dasatinib were observed in both GIST cell lines in vitro. IC50 values for ICG-dasatinib, unlabeled dasatinib, and imatinib were 13.9, 1.17, and 16.2 nM in GIST-T1 and 26.6, 3.63, and 47.6 nM in GIST-882M cells, respectively. ICG-dasatinib accumulated in subcutaneous xenografts in mice. Fluorescent signals were also observed in liver and gallbladder, indicating biliary excretion; however, fluorescence intensity of tumors was significantly higher than that of intestine after washing. Strong fluorescent signals were observed in orthotopic xenografts through the covering normal mucosa in rats.

CONCLUSIONS

Indocyanine green-labeled dasatinib could visualize GIST cells and xenografted tumors. The antitumor effect of ICG-dasatinib was preserved to the same degree as imatinib.

Outcomes of endoscopic ultrasound and endoscopic resection of gastrointestinal subepithelial lesions: a single-center retrospective cohort study

Background

Endoscopic resection (ER) is an emerging therapeutic alternative for subepithelial gastrointestinal lesions (SELs). We aimed to determine whether size, layer of origin, and histology based on endoscopic ultrasound (EUS) and EUS-guided sampling (EUS-GS) influenced the outcomes and selection of patients for ER.

Methods

We performed a retrospective review of patients who underwent EUS, EUS-GS and resection of SELs from 2012-2019. Two pathologists reviewed the histology and layer of origin of all resected specimens, serving as the criterion for EUS accuracy.

Results

Seventy-three patients were included, of whom 59 (81%) were gastric SELs. Per EUS, median lesion size was 21 mm (interquartile range 15-32), and 63 (86%) originated from the 4th layer. The overall accuracy of EUS and EUS-GS in predicting the layer of origin and histology was 88% (95% confidence interval [CI] 77-94%) and 96% (95%CI 87-98%), respectively. Based on EUS, 18 (25%) patients were referred for ER, 5 (7%) to laparoscopic-endoscopic cooperative surgery, and 50 (68%) to surgery. Size >20 mm was associated with the type of resection approach (P=0.005), while layer of origin and histology were not (P=0.06 and P=0.09, respectively). When SELs were inaccurately classified (n=4) there were no adverse events or revision of the resection approach.

Conclusions

EUS plays an important role in the outcome of resection approach for SELs, with size significantly influencing the selection for ER. In patients undergoing ER, no revised resections were needed when EUS was inaccurate.

Cost-effectiveness of rapid on-site evaluation of endoscopic ultrasound fine needle aspiration in gastrointestinal lesions

BACKGROUND AND AIM

Rapid on-site evaluation (ROSE) can improve adequacy rates of fine needle aspiration (FNA) and thus save operational costs. Our aim was to assess the cost-efficacy of ROSE performed during endoscopic ultrasound (EUS)-FNA of gastrointestinal lesions.

METHOD

This was a retrospective cohort study of 156 patients who underwent EUS-FNA for pancreatic, submucosal upper gastrointestinal, and adjacent lesions at Galilee Medical Center between 2012 and 2017. The patient cohort was divided into group A (62 patients, 39.7%) who underwent EUS-FNA with ROSE, and group B (94 patients, 60.3%) without ROSE. Cost analysis was based on the additional expenditure of repeated EUS-FNA sessions needed to reach accurate and final diagnosis in the two groups.

RESULTS

The overall cost was significantly higher in group B ($121 422) as compared to group A ($72 861), including the ROSE cost. Additional EUS-FNA sessions were needed in 11.3% and 23.4% in groups A and B, respectively. The additional cost to achieve final pathological diagnosis was $7203 and $24 696 in groups A and B, respectively (P = .02), yielding a savings of $252 per EUS-FNA case by adding ROSE. Notably, adding ROSE to the EUS-FNA exam for gastrointestinal non-pancreatic lesions resulted in even higher savings per case ($682.40). Moreover, adding ROSE improved specimen adequacy to achieve final pathological diagnosis (odds ratio = 7.13, P = .0005).

CONCLUSIONS

EUS-FNA with ROSE was cost-effective. Incorporating ROSE into the clinical practice of EUS-FNA saves costs and improves specimen adequacy.

Opportunities in cancer imaging: a review of oesophageal, gastric and colorectal malignancies

The incidence of gastrointestinal (GI) malignancy is increasing worldwide. In particular, there is a concerning rise in incidence of GI cancer in younger adults. Direct endoscopic visualisation of luminal tumour sites requires invasive procedures, which are associated with certain risks, but remain necessary because of limitations in current imaging techniques and the continuing need to obtain tissue for diagnosis and genetic analysis; however, management of GI cancer is increasingly reliant on non-invasive, radiological imaging to diagnose, stage, and treat these malignancies. Oesophageal, gastric, and colorectal malignancies require specialist investigation and treatment due to the complex nature of the anatomy, biology, and subsequent treatment strategies. As cancer imaging techniques develop, many opportunities to improve tumour detection, diagnostic accuracy and treatment monitoring present themselves. This review article aims to report current imaging practice, advances in various radiological modalities in relation to GI luminal tumour sites and describes opportunities for GI radiologists to improve patient outcomes.

Endoscopic ultrasound-guided fine-needle aspiration of pelvic lesions via the upper and lower gastrointestinal tract approaches

BACKGROUND

Combining upper and lower gastrointestinal tract (GI) approaches allows expansion of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) indications for pelvic lesions. The upper GI approach has been used for pelvic lesions around the level of the aortoiliac bifurcation in our institution. The aim of this study is to evaluate the feasibility and safety of EUS-FNA for pelvic lesions via the upper and lower GI approaches.

METHODS

All consecutive patients who underwent EUS-FNA for the pelvic lesion between January 2008 and December 2018 were retrospectively analyzed. Pelvic lesions were defined as lesions located around and below the aortoiliac bifurcation level. The primary outcome was technical success rate, and the secondary outcomes were the diagnostic capability of EUS-FNA for malignancy and the safety.

RESULTS

EUS-FNA for pelvic lesions was performed in 49 patients: upper and lower GI approaches were used in 28 and 21 patients, respectively. The technical success rates were 91.8% (45/49) in all patients: 89.3% (25/28) and 95.2% (20/21) with the upper and lower GI approaches, respectively. Among patients who achieved technical success, the diagnostic accuracy for malignancy was 97.8% (44/45) in all patients: 100% (25/25) and 95.0% (19/20) with the upper and lower GI approaches, respectively. One (2.0%) patient developed an adverse event of sigmoid colon perforation.

CONCLUSIONS

EUS-FNA for pelvic lesions via the upper and lower GI approaches was a safe, feasible, and effective method, although careful endoscopic manipulation is required to avoid perforation, especially with the lower GI approach. Further large-scale, well-designed studies are needed to validate our findings.

Assessment of the clinical usefulness of ultrasound-guided cytological specimens obtained from gastrointestinal lesions in dogs and cats

OBJECTIVES

Cytological biopsies are an integral additional test to an abdominal ultrasound when a lesion is identified, but there is little published on factors that that may impact achieving a clinically useful sample of gastrointestinal lesions obtained by ultrasound-guided fine-needle cytologic biopsy. This retrospective, descriptive study aimed to assess factors that may influence the clinical usefulness of submitted cytological samples collected from gastrointestinal lesions by ultrasound-guided percutaneous fine-needle cytologic biopsy.

MATERIAL AND METHODS

Gastrointestinal cytological samples obtained from 25 dogs and 19 cats over 2.5 years were reviewed and determined as clinically useful or clinically useless as per the cytology report. Variables dependent on the ultrasound exam that were used in the analysis included lesion location, lesion thickness, loss of gastrointestinal layering, and the number of slides submitted.

RESULTS

Thirty (30/44) of the submitted cytological samples were considered clinically useful. Factors associated with achieving a clinically useful sample in univariable models included the number of slides submitted and the thickness of the lesion. However, these two variables appear inter-related, as a weak correlation existed between them. Where histologic biopsies were obtained, a clinically useful sample had a partial or complete agreement with histology in three of 12 and eight of 12 cases, respectively.

CLINICAL SIGNIFICANCE

Ultrasound-guided fine-needle cytological biopsies of gastrointestinal masses provided a clinically useful sample in two-third of the cases, especially if more slides were provided to the cytologist and thicker lesions were sampled.

Utility of a 20G needle with a core trap in EUS-guided fine-needle biopsy for gastric submucosal tumors: A multicentric prospective trial

Background and Objectives

Differential diagnosis to estimate the malignant potential of gastric submucosal tumor (g-SMT) is important for decision-making. This study evaluated the use of a 20G needle with a core trap for EUS-guided fine-needle biopsy (EUS-FNB) for g-SMT.

Methods

This multicentric prospective trial was registered in the University Hospital Medical Information Network (UMIN000021410). Consecutive patients with g-SMT who presented at one of the nine Japanese Referral Centers between June 2017 and November 2018 were enrolled. All patients underwent EUS-FNB using a 20G needle with a core trap. Samples obtained with the first-needle pass were used for central pathological review. EUS-FNB was evaluated in terms of (i) technical success rate, (ii) adequacy for histological evaluation, (iii) rate of complications, (iv) accuracy for histological diagnosis of gastrointestinal stromal tumor (GIST), and (v) concordance between GIST mitotic index determined by EUS-FNB and after tumor resection.

Results

The study included 52 patients. The technical success rate of EUS-FNB was 100%. The adequacy rate for histological evaluation was 90.4% (P < 0.001). There were no complications related to EUS-FNB. Of the 38/52 patients who underwent surgical resection, 36 were finally diagnosed with GIST. The sensitivity, specificity, and accuracy of EUS-FNB for the histological diagnosis of g-SMT were 80.6%, 100%, and 81.6%, respectively. The concordance rate between the mitotic index on EUS-FNB and that after analysis of the resected tumor was 89.7%.

Conclusions

EUS-FNB using a 20G needle with a core trap is feasible, providing histological samples of sufficient quality for diagnosing g-SMT.

Endoscopic diagnosis and management of gastric subepithelial lesions

PURPOSE OF REVIEW

The purpose of this manuscript is to provide an in-depth review of gastric subepithelial lesions (SELs) and describe the current approach to endoscopic diagnosis and management of these lesions.

RECENT FINDINGS

Gastric SELs are a relatively frequent finding on routine endoscopy (incidence 0.2-3%). A systematic approach to diagnosis and management is key because many SELs are of little consequence, while others carry a high risk of malignant transformation. Because esophagogastroduodenoscopy (EGD) cannot delineate depth of invasion or subepithelial appearance, endoscopic ultrasound (EUS) should be considered a first-line modality. Recent data suggest EUS-guided fine needle biopsy (FNB) may be superior to traditional fine needle aspiration (FNA) for the diagnosis of gastric SELs due to its ability to obtain histologic specimens for immunohistochemical staining. Alternative techniques for tissue sampling (combined with simultaneous resection) include submucosal resection, endoscopic submucosal dissection (ESD), submucosal tunnelling with endoscopic resection (STER) or endoscopic full-thickness resection (EFTR).

SUMMARY

This review details the endoscopic diagnosis and management of gastric SELs. Although EUS-guided sampling remains a first-line strategy (preferably with FNB), recent techniques including ESD, STER and EFTR have the potential to provide additional diagnostic and therapeutic options.

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.

Superiority of mucosal incision-assisted biopsy over ultrasound-guided fine needle aspiration biopsy in diagnosing small gastric subepithelial lesions: a propensity score matching analysis

BACKGROUND

Gastric subepithelial lesions, including gastrointestinal stromal tumors, are often found during routine gastroscopy. While endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) has been the gold standard for diagnosing gastric subepithelial lesions, alternative open biopsy procedures, such as mucosal incision-assisted biopsy (MIAB) has been reported useful. The aim of this study is to evaluate the efficacy of MIAB for the diagnosis of gastric SELs compared with EUS-FNAB.

METHODS

We retrospectively analyzed medical records of 177 consecutive patients with gastric SELs who underwent either MIAB or EUS-FNAB at five hospitals in Japan between January 2010 and January 2018. Diagnostic yield, procedural time, and adverse event rates for the two procedures were evaluated before and after propensity-score matching.

RESULTS

No major procedure-related adverse events were observed in either group. Both procedures yielded highly-accurate diagnoses once large enough samples were obtained; however, such successful sampling was more often accomplished by MIAB than by EUS-FNAB, especially for small SELs. As a result, MIAB provided better diagnostic yields for SELs smaller than 20-mm diameter. The diagnostic yields of both procedures were comparable for SELs larger than 20-mm diameter; however, MIAB required significantly longer procedural time (approximately 13 min) compared with EUS-FNAB.

CONCLUSIONS

Although MIAB required longer procedural time, it outperformed EUS-FNAB when diagnosing gastric SELs smaller than 20-mm diameter.

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 tissue acquisition: From A to B

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

A case of gastric carcinoma with lymphoid stroma diagnosed by an endoscopic ultrasound-guided fine-needle biopsy

Endoscopic ultrasound-guided sampling is indicated to achieve an accurate diagnosis of subepithelial lesions of the stomach when a standard biopsy fails. Gastric carcinoma with lymphoid stroma (GCLS) is located under the epithelial layer with dense lymphocytic infiltration, making a pathological diagnosis by a biopsy difficult. We herein report a case of the pathological diagnosis of GCLS using an endoscopic ultrasound-guided fine-needle biopsy. The patient underwent distal gastrectomy and was diagnosed with Epstein-Barr virus-negative cancer.

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.

Mucosal incision-assisted biopsy versus endoscopic ultrasound-guided fine-needle aspiration with a rapid on-site evaluation for gastric subepithelial lesions: A randomized cross-over study

OBJECTIVES

This study aimed to compare the diagnostic yield of mucosal incision-assisted biopsy (MIAB) and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with a rapid on-site evaluation (ROSE) for gastric subepithelial lesions (SEL) suspected of being gastrointestinal stromal tumors (GIST) with an intraluminal growth pattern.

METHODS

This was a prospective randomized, cross-over multicenter study. The primary outcome was the diagnostic yield of EUS-FNA and MIAB. The secondary outcomes were the technical success rate, complication rate, procedure time and biopsy frequency.

RESULTS

A total of 47 patients were randomized to the MIAB group (n = 23) and EUS-FNA group (n = 24). There was no significant difference in the diagnostic yield of MIAB and EUS-FNA (91.3% vs 70.8%, P = 0.0746). The complication rates of MIAB and EUS-FNA did not differ to a statistically significant extent. The mean procedure time in the MIAB group was significantly longer than that in the EUS-FNA group (34 vs 26 min, P = 0.0011).

CONCLUSIONS

The diagnostic yield of MIAB was satisfactorily as high as EUS-FNA with ROSE for gastric SEL with an intraluminal growth pattern.

CT Versus Endoscopic Ultrasound for Differentiating Small (2-5 cm) Gastrointestinal Stromal Tumors From Leiomyomas

OBJECTIVE. Abdominal CT or endoscopic ultrasound is recommended for the evaluation of gastric subepithelial tumors. However, few studies have compared the diagnostic performance of these two methods. We compared the diagnostic performance of CT versus endoscopic ultrasound for gastric subepithelial tumors smaller than 5 cm. We also identified significant CT findings associated with the diagnosis of gastrointestinal stromal tumors. MATERIALS AND METHODS. Seventy-one patients with pathologically proven gastric subepithelial tumors were enrolled. We examined the diagnostic performance of CT compared with endoscopic ultrasound. We analyzed CT findings, including the location, long diameter (LD), short diameter (SD), LD-SD ratio, contour, margin, growth pattern, degree and pattern of enhancement, attenuation value, intralesional necrosis, calcification, hemorrhage, surface dimpling, and perilesional lymph node. RESULTS. Endoscopic ultrasound had a sensitivity of 77.6%, specificity of 61.5%, PPV of 90.0%, NPV of 38.1%, and accuracy of 74.6%. CT had a sensitivity of 84.5%, specificity of 53.8%, PPV of 89.1%, NPV of 43.8%, and accuracy of 78.9%. Multivariate analysis revealed that the presence of intralesional necrosis (odds ratio [OR], 10.88; p = 0.037) and an LD-SD ratio less than 1.5 (OR, 32.37; p = 0.002) were independent CT findings for the diagnosis of gastrointestinal stromal tumors. CONCLUSION. CT is as effective as endoscopic ultrasound for the diagnosis of gastric subepithelial tumors smaller than 5 cm. Tumors with intralesional necrosis and an LD-SD ratio less than 1.5 may require further pathologic diagnosis.

Lesion size determines diagnostic yield of EUS-FNA with onsite cytopathologic evaluation for upper gastrointestinal subepithelial lesions

BACKGROUND/AIMS

The aim of this study was to determine the diagnostic yield and factors influencing the diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for upper gastrointestinal (GI) subepithelial lesions (SELs) with rapid onsite cytopathologic evaluation.

MATERIALS AND METHODS

This is a single-center, retrospective study.

RESULTS

Among 22 patients who underwent EUS-FNA, a cytopathological diagnosis was reached in 16 (72.7%) patients. The EUS-FNA results were as follows: seven GISTs (31.8%), six leiomyomas (27.2%), four non-diagnostics (18%), two duplication cysts (9%), two spindle cell tumor (9%), and one ectopic pancreas (4.5%). The long-axis size was > 20 mm in 12 patients (average size: 31.3 ±9.3 mm) and < 20 mm (average size: 16.6 ±2.5 mm) in 10 patients. Diagnostic accuracy of EUS-FNA from lesions < 20 mm was 50% (5/10 lesions), and of lesions > 20 mm was 91.6% (11/12 lesions) (Fisher's exact test; p=0.028). Six patients underwent surgical resection. Surgical pathology results of five lesions (four GIST, one leiomyoma) were consistent with cytopathology results (83.3%).

CONCLUSION

The diagnostic yield of EUS-FNA of the upper GI SELs with an onsite cytopathologic interpretation was 72.7%. Lesion size < 2 cm significantly reduces the diagnostic yield of EUS-FNA for the upper GI SELs.

EUS-guided tissue sampling with a 20-gauge core biopsy needle for the characterization of gastrointestinal subepithelial lesions: A multicenter study

Background and Objective:

A new 20-gauge (G) biopsy needle with a core-trap technology has been developed with a large core size and enhanced flexibility. The aim of this multicenter study was to determine the feasibility, efficacy, and safety of EUS-guided fine-needle biopsy (EUS-FNB) with the new 20G needle in diagnosing subepithelial lesions (SELs).

Materials and Methods:

Retrospectively collected data from consecutive patients with SELs undergoing EUS-FNB with the 20G needle at five centers were analyzed.

Results:

A total of 50 SELs were included. The mean lesion size was 43.1 ± 17.5 mm. The lesion locations were esophagus (n = 1), stomach (n = 37), distal duodenum (n = 5), rectum (n = 6), and colon (n = 1). The procedure was technically feasible in all patients. Definitive diagnosis with full histological assessment including immunohistochemistry was obtained in 88% (44/50) of the patients. Considering malignant versus benign lesions, the sensitivity, specificity, positive predictive value, and negative predictive value were 85% (95% confidence interval [CI] 70.2–94.3), 100% (95% CI 58.7%–100%), 100% (95% CI 85.1%–100%), and 62.5 (95% CI 27.7–84.8), respectively. No major complications requiring additional care have been observed.

Conclusions:

In this multicenter study, we found that EUS-FNB with the new 20G core needle is an effective and safe method for the diagnosis of SELs with a high rate of producing adequate histological material and high diagnostic accuracy even from difficult-to-approach anatomical locations.

What should be known prior to performing EUS exams? (Part II)

In “What should be known prior to performing EUS exams, Part I,” the authors discussed the need for clinical information and whether other imaging modalities are required before embarking EUS examinations. Herewith, we present part II which addresses some (technical) controversies how EUS is performed and discuss from different points of view providing the relevant evidence as available. (1) Does equipment design influence the complication rate? (2) Should we have a standardized screen orientation? (3) Radial EUS versus longitudinal (linear) EUS. (4) Should we search for incidental findings using EUS?