The role of endosonography in submucosal tumours

Clinical course of asymptomatic duodenal subepithelial lesions

BACKGROUND/AIMS

There is limited knowledge regarding the management of duodenal subepithelial lesions (SELs) owing to a lack of understanding of their natural course. This study aimed to assess the natural course of asymptomatic duodenal SELs and provide management recommendations.

METHODS

Patients diagnosed with duodenal SELs and followed up for a minimum of 6 months were retrospectively investigated.

RESULTS

Among the 443,533 patients who underwent esophagogastroduodenoscopy between 2008 and 2020, duodenal SELs were identified in 0.39% (1,713 patients). Among them, 396 duodenal SELs were monitored for a median period of 72.5 months (interquartile range, 37.7-111.3 mo). Of them, 16 SELs (4.0%) showed substantial changes in size or morphology at a median follow-up of 35.1 months (interquartile range, 21.7-51.4 mo). Of these SELs with substantial changes, tissues of two SELs were acquired using endoscopic ultrasound-guided fine needle aspiration biopsy: one was a lipoma and the other was non-diagnostic. Three SELs were surgically or endoscopically removed; two were diagnosed as gastrointestinal stromal tumors, and one was a lipoma. An initial size of 20 mm or larger was associated with substantial changes during follow-up (p = 0.016).

CONCLUSION

While the majority of duodenal SELs may not exhibit substantial interval changes, regular follow-up with endoscopy may be necessary for cases with an initial size of 20 mm or larger, considering a possibility of malignancy.

Endoscopic resection in subepithelial lesions of the upper gastrointestinal tract: Experience at a tertiary referral hospital in The Netherlands

Background and study aims Histological confirmation of subepithelial lesions (SELs) in the upper gastrointestinal tract remains challenging. Endoscopic resection of SELs is increasingly used for its excellent diagnostic yield and opportunity to do away with continued surveillance. In this study, we aimed to evaluate the indications, success rates and complications of different endoscopic resection techniques for SELs at a large, tertiary referral hospital in Rotterdam, The Netherlands. Patients and methods Data between October 2013 and December 2021 were retrospectively collected and analyzed. Main outcomes were R0-resection rate, en bloc resection rate, recurrence rate, and procedure-related adverse events (AEs) (Clavien-Dindo). Secondary outcomes were procedure time, need for surgical intervention, and clinical impact on patient management. Results A total of 58 patients were referred for endoscopic resection of upper gastrointestinal SELs. The median diameter of lesions was 20 mm (range 7-100 mm). Median follow-up time was 5 months (range 0.4-75.7). Forty-eight procedures (83%) were completed successfully leading to en bloc resection in 85% and R0-resection in 63%. Procedure-related AEs occurred in six patients (13%). Severe complications (CD grade 3a) were seen in three patients. The local recurrence rate for (pre)malignant diagnosis was 2%. Additional surgical intervention was needed in seven patients (15%). A total of 32 patients (67%) could be discharged from further surveillance after endoscopic resection. Conclusions Endoscopic resection is a safe and effective treatment for SELs and offers valuable information about undetermined SELs for which repeated sampling attempts have failed to provide adequate tissue for diagnosis.

Feasibility and clinical value of linear endoscopic ultrasonography imaging in the lower gastrointestinal subepithelial lesions

Linear endoscopic ultrasonography (EUS) has been extensively utilized as a novel diagnostic and therapeutic modality across various fields. However, there have been relatively few studies focusing on lower gastrointestinal lesions. The aim of our study was to investigate the feasibility, safety and clinical value of linear EUS in the lower gastrointestinal subepithelial lesions. This was a retrospective study involving patients with lower gastrointestinal subepithelial lesions diagnosed by linear EUS from August 2019 to April 2023 at the Second Affiliated Hospital of Anhui Medical University. The data, including basic clinical information, linear EUS features, technical success rate, complications, and follow-up, were retrospectively collected and analyzed. A total of 69 patients with lower gastrointestinal subepithelial lesions underwent examination by linear EUS. Excluding the rectum, the technical success rate of linear EUS was 90.6% (29/32). Apart from the 7 patients whose diagnosis remained unknown, 3 patients with no abnormal EUS findings, and 3 patients failed the procedure, 56 patients were included in the final diagnostic performance analysis. The most common locations of the lesions were the rectum (37/56, 66.1%) and sigmoid colon (7/56, 12.5%). Based on endoscopy findings and pathological results, the most prevalent types of subepithelial lesions in the lower gastrointestinal tract were neuroendocrine tumor (NET) (12/56, 20.3%), lipoma (8/56, 13.6%) and extraluminal compression (8/56, 13.6%). The majority of lesions ranged in diameter from 1 to 3 cm (χ2 = 18.750, p < 0.001). After undergoing linear EUS examination, 36 patients received EUS-FNA (3/36), biopsy (5/36), endoscopic resection (25/36), or surgical excision (3/36) respectively. The pathological results of 29 patients were entirely consistent with the diagnosis made using linear EUS, with an 80.6% (29/36) diagnostic accuracy rate. Follow-up indicated that the lesions remained unchanged within 6-36 months. All patients tolerated the procedure well without any complications. In conclusion, linear EUS demonstrates technical feasibility, safety, and a high diagnostic accuracy for subepithelial lesions in the lower gastrointestinal tract.

Artificial Intelligence in the Prediction of Gastrointestinal Stromal Tumors on Endoscopic Ultrasonography Images: Development, Validation and Comparison with Endosonographers

Background/Aims

The accuracy of endosonographers in diagnosing gastric subepithelial lesions (SELs) using endoscopic ultrasonography (EUS) is influenced by experience and subjectivity. Artificial intelligence (AI) has achieved remarkable development in this field. This study aimed to develop an AI-based EUS diagnostic model for the diagnosis of SELs, and evaluated its efficacy with external validation.

Methods

We developed the EUS-AI model with ResNeSt50 using EUS images from two hospitals to predict the histopathology of the gastric SELs originating from muscularis propria. The diagnostic performance of the model was also validated using EUS images obtained from four other hospitals.

Results

A total of 2,057 images from 367 patients (375 SELs) were chosen to build the models, and 914 images from 106 patients (108 SELs) were chosen for external validation. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the model for differentiating gastrointestinal stromal tumors (GISTs) and non-GISTs in the external validation sets by images were 82.01%, 68.22%, 86.77%, 59.86%, and 78.12%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in the external validation set by tumors were 83.75%, 71.43%, 89.33%, 60.61%, and 80.56%, respectively. The EUS-AI model showed better performance (especially specificity) than some endosonographers. The model helped improve the sensitivity, specificity, and accuracy of certain endosonographers.

Conclusions

We developed an EUS-AI model to classify gastric SELs originating from muscularis propria into GISTs and non-GISTs with good accuracy. The model may help improve the diagnostic performance of endosonographers. Further work is required to develop a multi-modal EUS-AI system.

Feasibility of endoscopic resection and impact of endoscopic ultrasound-based surveillance on colorectal subepithelial tumors

BACKGROUND

Owing to the rising number of screening endoscopies and instrumental advances in endoscopic ultrasound (EUS), colorectal subepithelial tumors (SETs) are being increasingly detected. We aimed to determine the feasibility of endoscopic resection (ER) and the impact of EUS-based surveillance on colorectal SETs.

METHODS

The medical records of 984 patients with incidentally detected colorectal SETs between 2010 and 2019 were retrospectively reviewed. Overall, 577 colorectal SETs underwent ER, and 71 colorectal SETs underwent serial colonoscopy for > 12 months.

RESULTS

The mean tumor size (± standard deviation) of 577 colorectal SETs for which ER was performed was 7.0 ± 5.7 (median, 55; range, 1-50) mm; 475 tumors were located in the rectum and 102, in the colon. En bloc resection was achieved in 560/577 treated lesions (97.1%), and complete resection was achieved in 516/577 (89.4%). ER-related adverse events occurred in 15/577 (2.6%) patients. SETs originating from the muscularis propria showed a higher risk of ER-related adverse events and perforation than SETs arising from the mucosal or submucosal layer (odds ratio [OR] 19.786, 95% confidence interval [CI] 4.556-85.919; P = 0.002 and OR 141.250, 95% CI 11.596-1720.492; P = 0.046, respectively). Seventy-one patients were followed up after EUS without any treatment for > 12 months, during which three showed progression; eight, regression; and sixty, no changes.

CONCLUSIONS

ER for colorectal SETs showed excellent efficacy and safety. Additionally, colorectal SETs without high-risk features in surveillance with colonoscopy showed an excellent prognosis.

The effect of endoscopic ultrasound on the precise selection of endoscopic treatment for submucosal tumors in the upper gastrointestinal tract

OBJECTIVE

To summarize and discuss the guiding role of endoscopic ultrasound (EUS) in selecting endoscopic treatments for submucosal tumors (SMTs) in the upper gastrointestinal tract.

METHODS

A retrospective investigation was conducted on 156 SMT patients who received endoscopic resection guided by EUS in the endoscopy center of the Second Affiliated Hospital of Guangzhou University of Chinese Medicine from May 2019 to September 2021. Next, the size, pathological type, and distribution of lesions were analyzed; the correlation of the tumor origin with distribution of lesions and selection of treatments was explored; and the consistency of preoperative EUS diagnosis and postoperative pathological diagnosis was summarized and analyzed.

RESULTS

The tumor diameters of the included SMT patients ranged from 0.3 to 4 cm, with a mean diameter of 0.95 cm; the lesions were mostly located in the esophagus, gastric fundus or fundic cardia and gastric body. As for the pathological types, liomyoma was the most common tumor in the esophagus, liomyoma and mesenchymoma were mainly located in the fundic cardia and gastric body, and heterotopic pancreas was mostly discovered in the gastric sinus. Among 38 esophageal SMT patients, some with lesions originating from muscularis mucosa and submucosa under EUS mainly underwent endoscopic submucosal dissection (ESD) and endoscope band ligation (EBL); while others with lesions originated from muscularis propria mainly received submucosal tunneling endoscopic resection (STER). Of 115 gastric SMT patients under EUS, some with lesion origins from the muscularis mucosa and submucosa mainly underwent endoscopic submucosal excavation (ESE), while others from muscularis propria mainly underwent ESE, ESD, and endoscopic full-thickness resection (EFTR). Besides, 3 duodenal SMT patients with lesion origins from submucosa and muscularis propria under EUS were given ESD and ESE, respectively. Additionally, 121 cases showed a consistency between the EUS diagnosis and the postoperative pathological nature, and the consistency rate was 84.6%.

CONCLUSION

Clarifying the origin layer, size, growth pattern, and pathological nature of the lesion through preoperative EUS can guide the precise selection of endoscopic treatments, thereby ensuring a safe, effective, and complete surgical outcomes and reducing complications.

A prospective randomized noninferiority trial comparing conventional smears and SurePathTM liquid-based cytology in endoscopic ultrasound-guided sampling of esophageal, gastric, and duodenal lesions

BACKGROUND

Several liquid-based cytology (LBC) methods are currently used, but the diagnostic accuracy of each method is not well known. We aimed to compare the diagnostic performance of SurePathTM LBC and conventional smear (CS) cytology in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples of esophageal, gastric, and duodenal lesions.

METHODS

As a prospective randomized noninferiority study, patients who needed EUS-FNA due to subepithelial mass in the upper gastrointestinal tract were randomly assigned 1:1 to the LBC and CS groups. Cytologic preparation was carried out using a crossover design where 1 method was used for the first needle-pass sample and another method was used for the second needle-pass sample. The primary outcome was to compare the diagnostic performance between LBC and CS using the final diagnosis as the gold standard.

RESULTS

A total of 87 patients were randomized and 60 patients were analyzed. There were no differences between LBC and CS in diagnostic accuracy (91.7% vs 86.7%, P = .380), sensitivity (97.7% vs 90.7%, P = .169), specificity (76.5% vs 76.5%, P > .99), negative predictive value (92.9% vs 76.5%, P = .225), or positive predictive value (91.3% vs 90.7%, P = .921). The background of LBC was less bloody than that of CSs (5.0% vs 53.3%, P < .001) and the sample preparation time of LBC was shorter than that of CSs (29 ± 7 seconds vs 90 ± 17 seconds, P < .001).

CONCLUSION

In the EUS-FNA of a subepithelial mass in the upper gastrointestinal tract, the diagnostic performance of LBC was not inferior to that of CS. The field of view was better in LBC, because the background was less bloody and necrotic. As LBC is more convenient to perform and takes shorter time, it is expected that it can replace the CS method for EUS-FNA samples.

A Review of Colonoscopy in Intestinal Diseases

Since the development of the fiberoptic colonoscope in the late 1960s, colonoscopy has been a useful tool to diagnose and treat various intestinal diseases. This article reviews the clinical use of colonoscopy for various intestinal diseases based on present and future perspectives. Intestinal diseases include infectious diseases, inflammatory bowel disease (IBD), neoplasms, functional bowel disorders, and others. In cases of infectious diseases, colonoscopy is helpful in making the differential diagnosis, revealing endoscopic gross findings, and obtaining the specimens for pathology. Additionally, colonoscopy provides clues for distinguishing between infectious disease and IBD, and aids in the post-treatment monitoring of IBD. Colonoscopy is essential for the diagnosis of neoplasms that are diagnosed through only pathological confirmation. At present, malignant tumors are commonly being treated using endoscopy because of the advancement of endoscopic resection procedures. Moreover, the characteristics of tumors can be described in more detail by image-enhanced endoscopy and magnifying endoscopy. Colonoscopy can be helpful for the endoscopic decompression of colonic volvulus in large bowel obstruction, balloon dilatation as a treatment for benign stricture, and colon stenting as a treatment for malignant obstruction. In the diagnosis of functional bowel disorder, colonoscopy is used to investigate other organic causes of the symptom.

Endoscopic submucosal excavation for gastric plexiform fibromyxoma: A case report and systematic review of literature

Plexiform fibromyxoma (PF) is a rare mesenchymal tumor of which the pathogenesis and molecular changes are still unclear. Histologically, it is characterized by a cluster of bland spindle or ovoid cells growing in the mucoid or fibromyxoid stroma rich in small blood vessels. At present, surgical resection is the primary treatment for PF.

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.

A Submucosal Tumor-like Lesion of the Cervical Esophagus Similar to the Tonsillar Structures of Waldeyer's Ring: A Case Report

Esophageal submucosal tumors are rare, but their pathological types are diverse. In addition to the relatively common leiomyomas, some rare submucosal lesions are occasionally reported. Waldeyer's ring is described as a unique subtype of mucosa-associated lymphoid tissue, located in the naso-oropharynx. Studies have reported that Waldeyer's ring is the most common site of primary extranodal lymphoma in the head and neck. Interestingly, we encountered an esophageal submucosal tumor-like lesion similar to the tonsillar structures of Waldeyer's ring. A 38-year-old man underwent esophagoscopy after experiencing swallowing discomfort for 3 months. A protruding submucosal mass with slightly rough mucosa was found at the cervical esophagus approximately 20 cm from the incisors. Considering the possibility of the coexistence of a submucosal tumor and a mucosal lesion, as well as the continuous symptoms of swallowing discomfort, the patient underwent endoscopic submucosal dissection. The lesion was removed en bloc. However, histology revealed a lesion similar to the tonsillar structure of Waldeyer's ring between the lamina propria and submucosa. The patient was followed up for 6 months without recurrence or complaints. We report a new submucosal lesion and discuss its origin and treatment. Diagnostic ESD might be an effective option until its malignant potential is clarified.

Natural History of Asymptomatic Esophageal Subepithelial Tumors of 30 mm or Less in Size

BACKGROUND

No definite guidelines for the management of small esophageal subepithelial tumors (SETs) have been established, because there are limited data and studies on their natural history. We aimed to assess the natural history and propose optimal management strategies for small esophageal SETs.

METHODS

Patients diagnosed as esophageal SETs ≤ 30 mm in size between 2003 and 2017 using endoscopic ultrasound (EUS) with a minimal follow-up of 3 months were enrolled, and their esophagogastroduodenoscopy (EGD) and EUS were retrospectively reviewed.

RESULTS

Of 275 esophageal SETs in 262 patients, the initial size was < 10 mm, 10-20 mm, and 20-30 mm in 104 (37.8%), 105 (38.2%), and 66 (24.0%) lesions, respectively. Only 22 (8.0%) SETs showed significant changes in size and/or echogenicity and/or morphology at a median of 40 months (range, 4-120 months). Tissues of 6 SETs showing interval changes were obtained using EUS-guided fine needle aspiration biopsy; 1 was identified as a gastrointestinal stromal tumor (GIST) and was surgically resected, while the other 5 were leiomyomas and were regularly observed. Eight SETs showing interval changes were resected surgically or endoscopically without pathological confirmation; 1 was a GIST, 2 were granular cell tumors, and the other 5 were leiomyomas.

CONCLUSION

Regular follow-up with EGD or EUS may be necessary for esophageal SETs ≤ 30 mm in size considering that small portion of them has a possibility of malignant potential. When esophageal SETs ≤ 30 mm show significant interval changes, pathological confirmation may precede treatment to avoid unnecessary resection.

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.

An artificial intelligence system for distinguishing between gastrointestinal stromal tumors and leiomyomas using endoscopic ultrasonography

BACKGROUND

Gastrointestinal stromal tumors (GISTs) and gastrointestinal leiomyomas (GILs) are the most common subepithelial lesions (SELs). All GISTs have malignant potential; however, GILs are considered benign. Current imaging cannot effectively distinguish GISTs from GILs. We aimed to develop an artificial intelligence (AI) system to differentiate these tumors using endoscopic ultrasonography (EUS).

METHODS

The AI system was based on EUS images of patients with histologically confirmed GISTs or GILs. Participants from four centers were collected to develop and retrospectively evaluate the AI-based system. The system was used when endosonographers considered SELs to be GISTs or GILs. It was then used in a multicenter prospective diagnostic test to clinically explore whether joint diagnoses by endosonographers and the AI system can distinguish between GISTs and GILs to improve the total diagnostic accuracy for SELs.

RESULTS

The AI system was developed using 10 439 EUS images from 752 participants with GISTs or GILs. In the prospective test, 132 participants were histologically diagnosed (36 GISTs, 44 GILs, and 52 other types of SELs) among 508 consecutive subjects. Through joint diagnoses, the total accuracy of endosonographers in diagnosing the 132 histologically confirmed participants increased from 69.7 % (95 % confidence interval [CI] 61.4 %-76.9 %) to 78.8 % (95 %CI 71.0 %-84.9 %; P = 0.01). The accuracy of endosonographers in diagnosing the 80 participants with GISTs or GILs increased from 73.8 % (95 %CI 63.1 %-82.2 %) to 88.8 % (95 %CI 79.8 %-94.2 %; P = 0.01).

CONCLUSIONS

We developed an AI-based EUS diagnostic system that can effectively distinguish GISTs from GILs and improve the diagnostic accuracy of SELs.

Diagnosis of gastric submucosal tumors and estimation of malignant risk of GIST by endoscopic ultrasound. Comparison between B mode and contrast-harmonic mode

BACKGROUND

standard B-mode EUS assessment and EUS-guided tissue acquisition present sub-optimal diagnostic yield in the differential diagnosis of gastric submucosal tumors (SMTs).

AIMS

to evaluate the performances of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) to differentiate gastric SMTs and predict malignancy risk of gastrointestinal stromal tumors (GIST).

METHODS

a retrospective analysis was performed retrieving consecutive patients with gastric SMTs who underwent EUS between 2009 and 2014. Patients with available EUS video recordings and histological diagnosis were included. De-identified videos were presented to experts who made a diagnosis on B-mode EUS and CH-EUS.

RESULTS

fifty-four patients (29 female, 64-year-old) were included. Final diagnoses were 40 GISTs (8 high-grade), 9 leiomyomas, 5 rare SMTs. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the differential diagnosis of GIST were 95.0% vs. 85.0%, 57.1% for both techniques, and 85.2% vs. 77.8%, respectively. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the estimation of the malignancy GISTs risk were 62.5% vs. 100%, 83.3% vs. 82.1%, and 78.9% vs. 86.1%, respectively.

CONCLUSIONS

CH-EUS showed better diagnostic performance than B-mode EUS in differentiating leiomyomas and risk stratification of GIST. When considering high-grade GISTs, the addition of CH-EUS allowed an improvement in diagnostic accuracy.

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.

Efficacy and safety of endoscopic resection in treatment of small gastric stromal tumors: A state-of-the-art review

Gastrointestinal stromal tumors can occur in any part of the gastrointestinal tract, but gastric stromal tumors (GSTs) are the most common. All GSTs have the potential to become malignant, and these can be divided into four different grades by risk from low to high: Very low risk, low risk, medium risk, and high risk. Current guidelines all recommend early complete excision of GSTs larger than 2 cm in diameter. However, it is not clear whether small GSTs (sGSTs, i.e., those smaller than 2 cm in diameter) should be treated as early as possible. The National Comprehensive Cancer Network recommends that endoscopic ultrasonography-guided (EUS-guided) fine-needle aspiration biopsy and imaging (computed tomography or magnetic-resonance imaging) be used to assess cancer risk for sGSTs detected by gastroscopy to determine treatment. When EUS indicates a higher risk of tumor, surgical resection is recommended. There are some questions on whether sGSTs also require early treatment. Many studies have shown that endoscopic treatment of GSTs with diameters of 2-5 cm is very effective. We here address whether endoscopic therapy is also suitable for sGSTs. In this paper, we try to explain three questions: (1) Does sGST require treatment? (2) Is digestive endoscopy a safe and effective means of treating sGST? and (3) When sGSTs are at different sites and depths, which endoscopic treatment method is more suitable?

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.

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.

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.

EUS-guided sampling with 25G biopsy needle as a rescue strategy for diagnosis of small subepithelial lesions of the upper gastrointestinal tract

BACKGROUND AND STUDY AIMS

 This study was designed to evaluate the impact of additional tissue obtained with endoscopic ultrasound (EUS)-guided 25-gauge core biopsy needle (25G-PC) following an unsuccessful fine-needle biopsy (FNB) performed with larger-bore needles for the characterization of gastrointestinal subepithelial lesions (GI-SELs).

PATIENTS AND METHODS

 We prospectively collected and retrospectively analyzed information in our database from January 2013 to June 2017 for all patients with GI-SELs who received a EUS-guided FNB (EUS-FNB) with 25G-PC during the same procedure after failure of biopsy performed with larger-bore needle. Diagnostic yield, diagnostic accuracy and procedural complications were evaluated.

RESULTS

Sixteen patients were included in this study, 10 men and 6 women, median age 67.8 (range 43 to 76 years). Five patients were found to have a SEL localized in the distal duodenum, five in the gastric antrum, two in the gastric fundus and four in the gastric body. The mean size of the lesions was 20.5 mm (range 18 - 24 mm). EUS-FNB with 25G-PC enabled final diagnosis in nine patients (56.2 %). Regarding the subgroup of duodenal lesions, the procedure was successful in four of five (80 %). Final diagnoses with EUS-guided sampling were GIST (n = 6), leiomyoma (n = 2) and metastatic ovarian carcinoma (n = 1). No procedure-related complications were recorded.

CONCLUSION

 In patients with small GI-SELs, additional tissue obtained with 25G-PC could represents a "rescue" strategy after an unsuccessful procedure with larger-bore needles, especially when lesions are localized in the distal duodenum.

Gastric metastasis from ovarian adenocarcinoma presenting as a subepithelial tumor and diagnosed by endoscopic ultrasound-guided tissue acquisition

We describe an uncommon case of a patient with a metastatic adenocarcinoma of ovarian origin presented as a gastric subepithelial tumor (SET) and that was diagnosed by endoscopic ultrasound fine-needle biopsy (EUS-FNB). Malignant gastric lesions are rarely metastatic and the primary tumor is mainly breast, lung, esophageal cancer or cutaneous melanoma. Gastric metastasis from ovarian cancer is unusual, presenting synchronously with the primary tumor but also several years later than the initial diagnosis. From an endoscopic point of view, gastric metastasis does not present specific features. They may mimic both a primary gastric tumor or, less frequently, an SET. This case demonstrates the importance of EUS-FNB in distinguishing SETs and how this may alter treatment and prognosis.

Adult gastric duplication: an unknown condition within the spectrum of gastric submucosal lesions

BACKGROUND

Gastric duplication is an uncommon condition in adults representing only 4-8% of all gastrointestinal duplications. It develops as a cystic growth within the thick gastric wall that is surrounded by a layer of smooth muscle and lined with gastric mucosa. It is usually asymptomatic but may present with nonspecific abdominal symptoms as well as cyst-related complications such as gastrointestinal (GI) bleeding, ulceration and even pancreatitis. They are difficult to distinguish from other gastric submucosal lesions and may also mimic a gastrointestinal tumor (GIST) or mucinous cyst of the pancreas. Endoscopic ultrasound (EUS) is the most widely used diagnostic procedure and histology provides a definitive diagnosis.

CASE REPORT

We report the case of a 36-year-old female patient with a history of a "contained" perforated gastric ulcer that was managed conservatively. The patient was diagnosed with a gastric GIST which prompted a laparoscopic subtotal gastrectomy and Roux-en-Y reconstruction with a good postoperative outcome.

DISCUSSION

The definitive histological diagnosis was gastric duplication. Thus, the previous diagnosis of a "contained" perforated gastric ulcer was in fact a complication of the gastric duplication itself.

LAPAROENDOSCOPIC TRANSGASTRIC RESECTION OF SUBEPITHELIAL JUXTACARDIAC TUMORS

BACKGROUND

With a prevalence of 0.4-3.5%, subepithelial lesions of the upper digestive tract are discovered during endoscopic procedures. Treatment depends on etiological and pathophysiological information, ability to diagnose and the different technical resources available.

AIM

To demonstrate the effectiveness of a surgical technique that combines endoscopy and videolaparoscopy in the transgastric resection of subepithelial juxtacardic lesions.

METHOD

The patients were assisted with a technical combination between endoscopy and laparoscopy. After diagnosis of subepithelial tumor, intraoperative endoscopy was performed after pneumoperitoneum and placement of laparoscopic tweezers. Through endoscopy, the following steps were performed: demarcation of surgical margins, visualization of the intragastric image for the laparoscopic procedure and removal of the surgical specimen. By laparoscopy the following steps were performed: intragastric intra-abdominal access, resection of the part and closure of the gaps.

RESULTS

This technique was applied in two cases in order to evaluate its initial results. There were two videolaparoendoscopic resections of juxtacardiac gastric tumors of the posterior wall. Both had their endoscopic diagnosis confirmed. After laparoendoscopic and tomographic and/or ecoendoscopic diagnostic complementation and preoperative performance, the laparoendoscopic procedure was indicated. The patients had a good recovery, with a short hospitalization time and no complications.

CONCLUSION

The combined use of videolaparoscopy and endoscopy is a safe and effective technique for transgastric resection of juxtacardiac subepithelial lesions. It may be important for definitive diagnosis of the tumor.

Role of Endoscopic Ultrasonography in Guiding Treatment Plans for Upper Gastrointestinal Subepithelial Tumors

Gastrointestinal (GI) subepithelial tumors (SETs) are usually observed incidentally by endoscopy and have diverse prognoses, varying from benign to potentially malignant. When a GI SET is suspected, endoscopic ultrasonography (EUS) is the most accurate diagnostic method to differentiate it from extraluminal compression. To determine the nature of GI SETs, EUS is also the most accurate diagnostic method, and reveals the precise sonographic nature of the lesion. There are some SETs with typical EUS findings of GI SETs, but most hypoechoic lesions are difficult to diagnose based on EUS images alone. EUS is also helpful to determine GI wall involvement in SETs and optimal treatment methods. For the diagnosis of GI SETs, obtaining a proper specimen is essential. EUS-guided cytology or biopsy methods such as fine-needle aspiration, Tru-Cut biopsy, and the newly introduced fine-needle biopsy (FNB) provide good results. To increase the diagnostic yield for GI SETs, cytology with immunocytochemical staining is used for cytological interpretation, resulting in good diagnostic yields. Recently, EUS-FNB using cheese slicer technology has been introduced, and has been reported to provide good diagnostic results for GI SETs.

Feasibility of endoscopic submucosal dissection for upper gastrointestinal submucosal tumors treatment and value of endoscopic ultrasonography in pre-operation assess and post-operation follow-up: a prospective study of 224 cases in a single medical center

BACKGROUND AND AIMS

Diagram, diagnosis, and treatment with endoscopic submucosal dissection (ESD) for upper gastrointestinal submucosal tumors (SMTs) remain controversial, although endoscopic ultrasonography (EUS) and ESD have been established in diagnosis and treatment of SMTs in decades, respectively. In this study, we have investigated prospectively the profile of upper gastrointestinal SMTs, assessed the effect and feasibility of ESD in upper gastrointestinal SMTs treatment, as well as value of EUS in pre-ESD diagnosis and post-ESD follow-up for gastrointestinal SMTs.

METHODS

The upper gastrointestinal SMTs patients detected with endoscopy were further checked by EUS, then received series ESD treatment, and fulfilled 3- and 12-month follow-up EUS detection between July 2011 and March 2015. The parameters of SMTs with EUS examination (size, original layer) and treatment with ESD (en bloc resection rate, procedure time, procedure-related complications) were investigated and analyzed.

RESULTS

A total number of 224 patients with upper gastrointestinal SMTs were enrolled, and 108 (48.2 %) were men. The mean age was 50.4 ± 12.0 years (range 19-77 years). In total, 92 (41.1 %), 14 (6.3 %), 61 (27.2 %), 22 (9.8 %), 25 (11.2 %), and 10 (4.5 %) SMTs were located in esophagus, cardiac, fundus, body and antrum of stomach, duodenum, respectively. Two hundred and eight (92.9 %) patients were successfully treated with an en bloc ESD, while other 16 patients (7.1 %) suffered ESD failure (5.3 %, 12 case) or severe complications (1.8 %, 4 cases). The mean procedure time of ESD was 47.4 ± 27.3 min (range 10-180 min). The mean size of the SMTs measured with ESD samples was 13.6 ± 9.5 mm (range 4-113 mm). In total, 87 (38.8 %), 23 (10.3 %), and 114 (50.9 %) tumors originated from muscularis mucosa, submucosa, and muscularis propria, respectively. The majority of SMTs were leiomyoma (109, 48.7 %) and gastrointestinal stromal tumors (GIST) (77, 34.4 %), while other SMTs were confirmed as ectopic pancreas (21, 9.4 %), adenoid tumor (8, 3.6 %), lipoma (5, 2.2 %), neuroendocrine tumor (3, 1.3 %), and granulosa cell tumor (1, 0.4 %). The accuracy rate of EUS in pathological diagnosis or original layer was 82.6 % (185/224) or 74.6 % (167/224). Residual tumors were detected with EUS in 3 patients (1.3 %) in 3-month follow-up and no recurrence during 12-month follow-up period.

CONCLUSIONS

The predominant SMTs in upper gastrointestinal tract were leiomyoma in esophageal tumors which originated from muscularis mucosae and GIST in stomach which originated from muscularis propria detected satisfactorily with EUS. This study showed that ESD was a safe and effective treatment for upper gastrointestinal SMTs.

Clinical Applicability of Various Treatment Approaches for Upper Gastrointestinal Submucosal Tumors

Submucosal tumor (SMT) is a disease that is commonly discovered during endoscopic examination. With advances in endoscopic ultrasonography (EUS) technology, this technique has become the primary screening method for the diagnosis of upper gastrointestinal SMTs. The present study summarized the clinical data of patients who were examined and diagnosed with upper gastrointestinal SMTs by EUS, underwent endoscopic therapy or surgical treatment, and received final pathological results in our hospital between January 2011 and September 2014. Our results show that endoscopic therapy has become the main approach for the treatment of upper gastrointestinal SMTs with the development and maturation of endoscopic technology in recent years. Our conclusion suggests that the selection of endoscopic methods, such as endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and peroral submucosal tunneling endoscopic resection (STER), under the guidance of EUS is safe and effective for the treatment of upper gastrointestinal SMTs.

Colorectal Subepithelial Lesions

Most of subepithelial lesion (SEL) being identified was accidentally discovered as small bulging lesion covered with normal mucosa from endoscopic screening. The type of treatment and prognosis vary depending on the type of tumor, it would be crucial to perform an accurate differential diagnosis. Since the differentiation of SEL relied on the indirect findings observed from the mucosal surface using an endoscopy only in the past, it was able to confirm the presence of lesion only but difficult to identify complex detailed nature of the lesion. However, after the endoscopic ultrasonography (EUS) was introduced, it became possible to identify extrinsic compression, and size of intramural tumors, internal properties and contour so that it gets possible to have differential diagnosis of lesions and prediction on the lesion whether it is malignant or benign. In addition, the use of EUS-guided fine needle aspiration and EUS-guided core biopsy made it possible to make histological differential diagnosis. This study intended to investigate endoscopic and EUS findings, histological diagnosis, treatment regimen and impression of colorectal SELs.

Idiopathic granulomatous gastritis diagnosed with endoscopic ultrasound-guided fine-needle aspiration: report of a case

A 71-year-old man in whom a gastric submucosal lesion was found incidentally was referred to our hospital for detailed examination. Esophagastroduodenoscopy showed a submucosal lesion in the body of the stomach. Endoscopic ultrasound revealed a 15-mm hypoechoic round mass with calcifications arising from the muscular layer. Confusing the diagnosis, it resembled a gastrointestinal mesenchymal tumor. Subsequently, endoscopic ultrasound-guided fine-needle aspiration was conducted for definitive diagnosis. Pathologic analysis showed a granuloma. Because this patient had no prior exposure to tuberculosis or Helicobacter pylori infection and had no abnormal laboratory data, this submucosal lesion was diagnosed as idiopathic granulomatous gastritis.

Evaluation of gastric submucosal tumors using endoscopically visualized features with submucosal endoscopy

Although the macroscopic characteristics of submucosal tumors (SMTs), such as gastrointestinal stromal tumors (GISTs), have been characterized, the assessment of SMTs by their endoscopically visualized features (EVF; which are observed by endoscopic imaging under direct view) remains unevaluated. The aim of the present study was to investigate the potential of endoscopic diagnostics for SMTs using EVF. The EVF of 26 gastric SMT cases, in which the final pathological diagnosis was obtained by core biopsy using the submucosal endoscopy with mucosal flap method, were retrospectively reviewed. Each type of SMT was classified according to the following five EVF: Color, clarity, shape, tumor coating and solidity. Additionally, the EVF of 13 low-risk GISTs and 13 benign submucosal tumors (BSTs) were comparatively evaluated for the five abovementioned EVF. Similar trends were identified between the low-risk GISTs, granular cell tumors and the schwannoma with regard to EVF. However, while these tumors exhibited cloudy EVF, the leiomyomas tended to exhibit clear EVF. Among SMTs of the heterotopic pancreas type, the EVF demonstrated particularly small nodules of the pancreatic tissue itself. Although the sample size included in the present study is small, a classification system for gastric SMTs was proposed according to the EVF. When compared with the BST group, the GIST group demonstrated a significantly higher frequency of tumors that exhibited a combination of three EVF (white, cloudy and rigid) that are consistent with all gastric GISTs (P<0.05). Gastric SMTs may be classified based on the EVF, which indicates that the EVF possess potential diagnostic value for the differentiation of GISTs from BSTs.

Submucosal tunneling endoscopic resection of esophageal submucosal tumors originating from the muscularis propria layer: A retrospective analysis

AIM: To evaluate the safety and efficacy of submucosal tunneling endoscopic resection (STER) for esophageal submucosal tumors (SMTs) originating from the muscularis propria layer.

METHODS: Between April 2012 and August 2013, 5 patients with esophageal SMTs originating from the muscularis propria layer were treated by STER. The key steps were as follows: (1) creating a submucosal tunnel to uncover the tumor; (2) resecting the tumor en bloc by endoscopic resection techniques; and (3) closing the mucosal incision site after the tumor was removed.

RESULTS: STER was successfully performed in all 5 cases (success rate: 100%). The mean tumor size was 1.6 cm (range, 1.0-2.5 cm). The mean procedure time was 108.6 min (range, 80-138 min). The average hospital stay was 5.8 d (range, 5-7 d). The mean number of clips used was 7 (5-9). Pathological diagnosis of the tumors was leiomyoma (4/5) and mesenchymal tumor (1/5) with lateral and basal resection margins free of tumor tissue. During the procedure, one patient developed subcutaneous emphysema, who recovered after conservative treatment. No residual or recurrent tumors were detected during the 6-mo (4 patients) and 12-mo (1 patient) follow-up period.

CONCLUSION: STER seems to be a safe and effective procedure for treatment of esophageal SMTs originating from the muscularis propria layer, but its indications need to be further investigated.

Differential clinical and pathological characteristics of esophageal stromal tumors and leiomyomata

The objective of the study was to assess the differences in clinical and pathological characteristics between esophageal stromal tumor and leiomyoma. Data from 93 esophageal stromal tumors and leiomyomata cases were retrospectively analyzed, including clinical symptoms, endoscopic features, pathological characteristics, immunohistochemistry (IHC), and treatment. All cases underwent endoscopic ultrasonography examination before treatment. Lesions arising from the muscularis mucosa were resected by endoscopic mucosal resection or endoscopic submucosal dissection. Lesions arising from the muscularis propria were resected by surgery. All specimens were examined by IHC. Patients were followed up after endoscopic mucosal resection or endoscopic submucosal dissection. No difference was observed in clinical symptoms and endoscopic features between the two groups. Endoscopic ultrasonography demonstrated all lesions to be hypoechoic and well circumscribed. Most lesions >2 cm had heterogeneous internal ultrasound signal. In esophageal stromal tumor, 100% (29/29) were CD117-positive and DOG-1-positive; 72.4% (21/29) and 51.7% (15/29) were CD34-positive and smooth muscle actin-positive, respectively. In esophageal leiomyomata, 100% (64/64) were smooth muscle actin-positive and desmin-positive; 100% were CD117-negative and DOG-1-negative. No local recurrence was detected in followed up patients (n = 49) after an average of 1.8 years (1.0-3.0 years). IHC analyses are important for distinguishing esophageal stromal tumor from leiomyoma. Early endoscopic resection is an effective treatment option for esophageal stromal tumors >1 cm.

Effectiveness of an endoscopic biopsy procedure using EUS-FNA and EMR-C for diagnosing adenocarcinoma arising from ectopic pancreas: two case reports and a literature review

Adenocarcinomas arising from the ectopic pancreas in the gastrointestinal wall are rarely described in the literature. In addition, obtaining an accurate preoperative diagnosis is difficult in most cases because these adenocarcinomas occur primarily in the submucosal layer and form submucosal tumors. Endoscopic ultrasonography-guided fine-needle aspiration and endoscopic mucosal resection with a transparent plastic cap-fitted panendoscope followed by a biopsy are useful for histological typing and making the differential diagnosis of adenocarcinoma, gastrointestinal stromal tumor, malignant lymphoma or other. These procedures represent the first step toward diagnosing ectopic pancreatic adenocarcinoma. We herein report two such cases with a review of the pertinent literature.

Diagnosing a gastric submucosal tumor using jumbo biopsy "unroofing" technique: a case report and review of the literature

We report a case of a 40-year-old female who presented with dyspeptic symptoms for six months. Upper GI endoscopy revealed a submucosal nodule in gastric antrum. Using “jumbo biopsy unroofing technique” we were able to get adequate tissue for analysis. Histopathology revealed a type III gastric carcinoid. Patient was treated with laparoscopic distal subtotal gastrectomy with Roux-en-Y reconstruction and partial omentectomy. Although there was no evidence of metastasis on initial presentation, eighteen months later, patient was found to have multiple metastatic lesions in her liver. Patient's lesions were treated with intra-arterial (hepatic artery) Yttrium-90.

Endoscopic ultrasonography for gastrointestinal submucosal lesions

Advances in endoscopic imaging technology have led to the detection of more cases of gastrointestinal submucosal lesions (SMLs). Endoscopic ultrasonography (EUS) was previously known as the best imaging procedure to characterize SMLs. However, the progress of endoscopic submucosal dissection (ESD) has raised some new questions concerning the role of EUS in the diagnosis of SMLs. What is the diagnostic accuracy of EUS for SMLs? How is the nature of SMLs determined? How is the layer of origin identified? What is the preoperative value of EUS for ESD? In this review, we will discuss the endosonographic features of SMLs, the diagnostic accuracy of EUS, the ability of EUS to distinguish benign and malignant SMLs, the value of EUS-guided fine-needle aspiration (FNA), and the value of EUS in clinical surveillance.

Endoscopic ultrasound fine needle aspiration: Technique and applications in clinical practice

Since its initial report in 1992, endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has now been incorporated into the diagnostic and staging algorithm for the evaluation of benign and malignant diseases of the gastrointestinal tract and of adjacent organs. Its introduction constitutes a major breakthrough in the endoscopic field and has gradually transformed EUS from a pure imaging modality into a more interventional. In addition, the possibility of collecting samples, providing a definitive cytological and/or histological evidence of the presence of malignancy, has strongly contributed to changing EUS from a subjective, highly operator dependant procedure into a more objective one. This article will review the instrumentation, technique and the most important clinical applications of EUS-FNA.

Endoscopic ultrasound-guided fine needle aspiration in submucosal lesion

A submucosal lesion, more appropriately a subepithelial lesion, is hard to diagnose. Endoscopic ultrasonography is good to differentiate the nature of submucosal lesion. For definite diagnosis, tissue acquisition from submucosal lesion is necessary, and many methods have been introduced for this purpose mainly by endoscopic ultrasonography, such as endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), EUS-guided Trucut Biopsy (TCB), and EUS-guided fine needle biopsy (FNB). For EUS-FNA, adequate processing of specimen is important, and for proper diagnosis of EUS-FNA specimen, both cytologic and histologic examinations, including immunohistochemical stains, are important. All gastrointestinal stromal tumors have some degree of malignant potential, so there have been a lot of efforts and methods to increase diagnostic yields of submucosal lesion. We herein review the current hot topics on EUS-FNA for submucosal tumor, such as needles, on-site cytopathologists, immunohistochemical stains, EUS-TCB, EUS-FNB, Ki-67 labelling index, DOG1, and combining EUS-FNA and EUS-TCB.

Endoscopic submucosal dissection for treatment of esophageal submucosal tumors originating from the muscularis propria layer

BACKGROUND

The technique of endoscopic submucosal dissection (ESD), which was developed for en bloc resection of large lesions in the stomach, has been widely accepted for the treatment of early gastric cancer. It is being used for muscularis propria tumors of the digestive tract and has produced positive therapeutic effects.

OBJECTIVE

To study the feasibility of ESD for the removal of esophageal muscularis propria tumors and to evaluate the efficacy and safety of ESD for this treatment.

DESIGN

Single-center, retrospective study.

SETTING

University hospital.

PATIENTS

Thirty esophageal muscularis propria tumors from 28 patients were treated with ESD between December 2008 and December 2010. We defined esophageal muscularis propria tumors as esophageal submucosal tumors originating from the muscularis propria layer.

INTERVENTION

ESD.

MAIN OUTCOME MEASUREMENTS

Tumor characteristics, complications, en bloc resection rate, and local recurrence rate were evaluated.

RESULTS

Among the 28 patients, 11 were women (39.3%). The median age was 49.32 years (range 22-62 years). Mean (± SD) tumor size was 1.25 ± 0.70 cm (range 0.5-3.0 cm). Except for 2 failed cases (one changed to surgery and the other changed to nylon ligation), 26 cases with 28 tumors (2 cases had 2 tumors) originating from the muscularis propria of the esophagus were successfully resected by ESD. The en bloc resection rate was 93.3% (28/30). The median ESD procedure time was 73.5 minutes (range 30-120 minutes). Perforation occurred in 2 cases during dissection of the lesion, which was closed with metal endoclips. Pneumothorax occurred after the treatment in both cases. Closed thoracic drainages were initiated, and the patients recovered quickly without surgery. Pathological examination confirmed 27 leiomyomas and 1 GI stromal tumor. The curative resection rate was 100% (28/28). There was no recurrence during a 3 to 27-month follow-up period.

LIMITATIONS

The limitation of the study was its retrospective design.

CONCLUSION

ESD offers the promise of localized treatment of esophageal muscularis propria tumors with relatively few complications and low mortality. It makes the resection of whole lesions possible and provides precise histologic information.

Diagnosis of gastrointestinal mucosal and submucosal protuberant lesions by endoscopic ultrasonography: an analysis of 432 cases

AIM: To study the clinical value of endoscopic ultrasonography (EUS) in the diagnosis of mucosal and submucosal protuberant lesions of the digestive tract.

METHODS: A total of 3 100 patients with mucosal and submucosal protuberant lesions of the digestive tract who underwent EUS before operation were retrospectively analyzed, and 432 patients who also underwent postoperative pathological examination after endoscopic biopsy, endoscopic resection, EUS or ESD were included in this study. The results of preoperative examination were compared with those of postoperative pathological diagnosis.

RESULTS: The diagnostic coincidence rate between pathological examination and EUS was 88.18% (306/347) for mucosal protuberant lesions, 55.29% (47/85) for submucosal protuberant lesions, and 81.71% (353/432) for all protuberant lesions. Rare diseases and diseases not listed in the endoscopic ultrasound map accounted for a major share of the non-coincidence cases.

CONCLUSION: EUS can help judge the origin, characteristics of echo, as well as tumor size, margin for protuberant lesions of the digestive tract, but can not accurately identify the nature of the disease. Pathological examination following endoscopic biopsy, surgery, ESD or EMR is necessary in patients with a doubtful diagnosis.

Diagnosis of subepithelial tumors in the upper gastrointestinal tract by endoscopic ultrasonography

Endoscopic ultrasonography (EUS) is the most accurate procedure for detecting and diagnosing subepithelial tumors, due to its higher sensitivity and specificity than other imaging modalities. EUS can characterize lesions by providing information on echogenic origin, size, borders, homogeneity, and the presence of echogenic or anechoic foci. Linear echoendoscopes, and recently also electronic radial echoendoscopes, can be used with color Doppler or power Doppler to assess the vascular signals from subepithelial masses, and thus permit the differentiation of vascular structures from cysts, as well as the assessment of the tumor blood supply. However, the diagnostic accuracy of EUS imaging alone has been shown to be low in subepithelial lesions with 3rd and 4th layers. It is also difficult to differentiate exactly between benign and malignant tumors and to gain an accurate picture of histology using EUS. On the other hands, EUS guided fine needle aspiration (EUS-FNA) can provide samples for cytologic or histologic analysis. Hypoechoic lesions of the 3rd and the 4th EUS layers, more than in 1 cm diameter are recommended, and histologic confirmation using endoscopic submucosal resection or EUS-FNA should be obtained when possible. Therefore, EUS-FNA plays an important role in the clinical management of subepithelial tumors. Furthermore improvements in endoscopic technology are expected to be more useful modalities in differential diagnosis and discrimination between benign and malignant subepithelial tumors.