Characterization of subepithelial lesions of the stomach and esophagus by contrast-enhanced EUS: A retrospective study

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.

Endoscopic ultrasound artificial intelligence-assisted for prediction of gastrointestinal stromal tumors diagnosis: A systematic review and meta-analysis

BACKGROUND

Subepithelial lesions (SELs) are gastrointestinal tumors with heterogeneous malignant potential. Endoscopic ultrasonography (EUS) is the leading method for evaluation, but without histopathological analysis, precise differentiation of SEL risk is limited. Artificial intelligence (AI) is a promising aid for the diagnosis of gastrointestinal lesions in the absence of histopathology.

AIM

To determine the diagnostic accuracy of AI-assisted EUS in diagnosing SELs, especially lesions originating from the muscularis propria layer.

METHODS

Electronic databases including PubMed, EMBASE, and Cochrane Library were searched. Patients of any sex and > 18 years, with SELs assessed by EUS AI-assisted, with previous histopathological diagnosis, and presented sufficient data values which were extracted to construct a 2 × 2 table. The reference standard was histopathology. The primary outcome was the accuracy of AI for gastrointestinal stromal tumor (GIST). Secondary outcomes were AI-assisted EUS diagnosis for GIST vs gastrointestinal leiomyoma (GIL), the diagnostic performance of experienced endoscopists for GIST, and GIST vs GIL. Pooled sensitivity, specificity, positive, and negative predictive values were calculated. The corresponding summary receiver operating characteristic curve and post-test probability were also analyzed.

RESULTS

Eight retrospective studies with a total of 2355 patients and 44154 images were included in this meta-analysis. The AI-assisted EUS for GIST diagnosis showed a sensitivity of 92% [95% confidence interval (CI): 0.89-0.95; P < 0.01), specificity of 80% (95%CI: 0.75-0.85; P < 0.01), and area under the curve (AUC) of 0.949. For diagnosis of GIST vs GIL by AI-assisted EUS, specificity was 90% (95%CI: 0.88-0.95; P = 0.02) and AUC of 0.966. The experienced endoscopists' values were sensitivity of 72% (95%CI: 0.67-0.76; P < 0.01), specificity of 70% (95%CI: 0.64-0.76; P < 0.01), and AUC of 0.777 for GIST. Evaluating GIST vs GIL, the experts achieved a sensitivity of 73% (95%CI: 0.65-0.80; P < 0.01) and an AUC of 0.819.

CONCLUSION

AI-assisted EUS has high diagnostic accuracy for fourth-layer SELs, especially for GIST, demonstrating superiority compared to experienced endoscopists' and improving their diagnostic performance in the absence of invasive procedures.

Endoscopic Ultrasound Advanced Techniques for Diagnosis of Gastrointestinal Stromal Tumours

Gastrointestinal Stromal Tumors (GISTs) are subepithelial lesions (SELs) that commonly develop in the gastrointestinal tract. GISTs, unlike other SELs, can exhibit malignant behavior, so differential diagnosis is critical to the decision-making process. Endoscopic ultrasound (EUS) is considered the most accurate imaging method for diagnosing and differentiating SELs in the gastrointestinal tract by assessing the lesions precisely and evaluating their malignant risk. Due to their overlapping imaging characteristics, endosonographers may have difficulty distinguishing GISTs from other SELs using conventional EUS alone, and the collection of tissue samples from these lesions may be technically challenging. Even though it appears to be less effective in the case of smaller lesions, histology is now the gold standard for achieving a final diagnosis and avoiding unnecessary and invasive treatment for benign SELs. The use of enhanced EUS modalities and elastography has improved the diagnostic ability of EUS. Furthermore, recent advancements in artificial intelligence systems that use EUS images have allowed them to distinguish GISTs from other SELs, thereby improving their diagnostic accuracy.

Role of Endoscopy in Esophageal Tuberculosis: A Narrative Review

Esophageal tuberculosis (ET) is a rare infectious disease of the gastrointestinal tract. Awareness of ET is deficient due to its low incidence. Unexplained dysphagia and upper gastrointestinal bleeding are the most common symptoms of ET. The prognosis is generally good if patients are diagnosed properly and receive anti-tubercular treatment promptly. However, ET is difficult to differentiate from other diseases. Endoscopic techniques such as esophagogastroduodenoscopy (EGD), endoscopic ultrasonography (EUS), contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS), elastography, and endoscopic ultrasound--guided fine-needle aspiration (EUS-FNA) improve the diagnosis of ET. Thus, the characteristics of ET and other difficult-to-detect diseases according to EGD and EUS were summarized. Intriguingly, there is no literature relevant to the application of CH-EUS and elastography in ET. The authors' research center was first in introducing CH-EUS and elastography into the field of ET. The specific manifestation of ET based on CH-EUS was discovered for the first time. Correlative experience and representative cases were shared. The role of endoscopy in acquiring esophageal specimens and treatment for ET was also established. In this review, we aim to introduce a promising technology for the diagnosis and treatment of ET.

Efficacy of endoscopic ultrasound in the evaluation of small gastrointestinal stromal tumors

BACKGROUND

Gastrointestinal stromal tumors (GISTs) with a diameter of < 2 cm are called small GISTs. Currently, endoscopic ultrasound (EUS) is widely used as a regular follow-up method for GISTs, which can also provide a preliminary basis for judging the malignancy potential of lesions. However, there are no studies on the accuracy of EUS to assess the malignant potential of small GISTs.

AIM

To evaluate the efficacy of EUS in the diagnosis and risk assessment of small GISTs.

METHODS

We collected data from patients with small GISTs who were admitted to Shengjing Hospital of China Medical University between October 2014 and July 2019. The accurate diagnosis and risk classifications of patients were based on the pathological assessment according to the modified National Institute of Health criteria after endoscopic resection or laparoscopic surgery. Preoperative EUS features (marginal irregularity, cystic changes, homogeneity, ulceration, and strong echogenic foci) were retrospectively analyzed. The assessment results based on EUS features were compared with the pathological features.

RESULTS

A total of 256 patients (69 men and 187 women) were enrolled. Pathological results included 232, 16, 7, and 1 very low-, low-, intermediate-, and high-risk cases, respectively. The most frequent tumor location was the gastric fundus (78.1%), and mitoses were calculated as > 5/50 high power field in 8 (3.1%) patients. Marginal irregularity, ulceration, strong echo foci, and heterogeneity were detected in 1 (0.4%), 2 (0.8%), 22 (8.6%), and 67 (65.1%) patients, respectively. However, cystic changes were not detected. Tumor size was positively correlated with the mitotic index (P < 0.001). Receiver operating curve analysis identified 1.48 cm as the best cut-off value to predict malignant potential (95% confidence interval: 0.824–0.956). EUS heterogeneity with tumor diameters > 1.48 cm was associated with higher risk classification (P < 0.05).

CONCLUSION

Small GISTs (diameters > 1.48 cm) with positive EUS features should receive intensive surveillance or undergo endoscopic surgery. EUS and dissection are efficient diagnostic and therapeutic approaches for small GISTs.

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.

The necessarity of treatment for small gastric subepithelial tumors (1-2 cm) originating from muscularis propria: an analysis of 972 tumors

Background and objectives

Up till now, there are still controversies about the specific indication of endoscopic resection for small gastric subepithelial tumors (gSETs) originating from muscularis propria. We aimed to investigate the safety of endoscopic resection and postoperative pathology analysis.

Method

The patients with primary small gSETs originating from muscularis propria, treated by endoscopic resection in the endoscopic center of Shengjing Hospital between January, 2011 and September, 2019 were enrolled. The complete resection rate, adverse events and clinicopathological features were recorded.

Result

A total of 936 patients with 972 gastric SETs ≤ 2 cm originating from muscularis propria were included in our study. All the lesions were successfully treated by endoscopic resection. Nearly half of lesions were proved to be gastrointestinal stromal tumor (GIST) [n = 411 (42.3%)] according to postoperative pathology. All the objects were further subdivided into 2 groups, ≤ 1 cm, > 1 and ≤ 2 cm gSETs. The risk of gastric GIST of intermediate/high risk in the group (> 1 and ≤ 2 cm gSETs) is 8.41 times as that of gastric GIST in the group (the size of gastric ≤ 1 cm gSETs) (P < 0.05).

Conclusion

Endoscopic resection is a safe and effective treatment for small gSETs. gSETs (1–2 cm) is more risky than gSETs (≤ 1 cm) and should be resected. This should be evaluated by further studies.

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.

Application of ultrasonography in predicting the biological risk of gastrointestinal stromal tumors

OBJECTIVES

To explore and establish a reliable and noninvasive ultrasound model for predicting the biological risk of gastrointestinal stromal tumors (GISTs).

MATERIALS AND METHODS

We retrospectively reviewed 266 patients with pathologically-confirmed GISTs and 191 patients were included. Data on patient sex, age, tumor location, biological risk classification, internal echo, echo homogeneity, boundary, shape, blood flow signals, presence of necrotic cystic degeneration, long diameter, and short/long (S/L) diameter ratio were collected. All patients were divided into low-, moderate-, and high-risk groups according to the modified NIH classification criteria. All indicators were analyzed by univariate analysis. The indicators with inter-group differences were used to establish regression and decision tree models to predict the biological risk of GISTs.

RESULTS

There were statistically significant differences in long diameter, S/L ratio, internal echo level, echo homogeneity, boundary, shape, necrotic cystic degeneration, and blood flow signals among the low-, moderate-, and high-risk groups (all p < .05). The logistic regression model based on the echo homogeneity, shape, necrotic cystic degeneration and blood flow signals had an accuracy rate of 76.96% for predicting the biological risk, which was higher than the 72.77% of the decision tree model (based on the long diameter, the location of tumor origin, echo homogeneity, shape, and internal echo) (p = .008). In the low-risk and high-risk groups, the predicting accuracy rates of the regression model reached 87.34 and 81.82%, respectively.

CONCLUSIONS

Transabdominal ultrasound is highly valuable in predicting the biological risk of GISTs. The logistic regression model has greater predictive value than the decision tree model.

Robotic-assisted surgery for esophageal submucosal tumors: a single-center case series

Esophageal submucosal tumors (SMTs) are rare heterogenous clinical entities. The surgical resection can be performed in different surgical approaches. However, the robotic surgical strategy is poorly documented in the treatment of SMTs. We present our series of operated esophageal SMTs approached via robotic-assisted surgery. Six patients with symptomatic esophageal submucosal tumors underwent robotic surgery within a 3-year period. The performed procedures were robotic-assisted enucleation, robotic esophagectomy (RAMIE) and reverse hybrid robotic esophagectomy. Patients’ clinical data, intra/postoperative outcomes, and histopathological features were retrieved from the institution’s prospective database. Five of six patients were scheduled for upfront surgery: four underwent robotic enucleation (three leiomyoma and one suspected GIST) and one underwent reverse hybrid robotic esophagectomy (suspected GIST). One patient, diagnosed with GIST, was treated with neoadjuvant Imatinib therapy, before undergoing a RAMIE. No major intra-operative complications were recorded. Median length of stay was 7 days (6–50), with a longer post-operative course in patients who underwent esophagectomy. Clavien–Dindo > 3a complications occurred in two patients, aspiration pneumonia and delayed gastric emptying. The final histopathological and immuno-histochemical diagnosis were leiomyoma, well-differentiated GIST, low-grade fibromyxoid sarcoma and Schwannoma. Robotic-assisted surgery seems to be a promising option for surgical treatment strategies of benign or borderline esophageal submucosal tumors.

Thoracoscopic resection of a large lower esophageal schwannoma: A case report and review of the literature

BACKGROUND

Esophageal schwannomas originating from Schwann cells are extremely rare esophageal tumors. They commonly occur in the upper and middle esophagus but less frequently in the lower esophagus. Herein, we report a rare case of a large lower esophageal schwannoma misdiagnosed as a leiomyoma. We also present a brief literature review on lower esophageal schwannomas.

CASE SUMMARY

A 62-year-old man presented with severe dysphagia lasting 6 mo. A barium esophagogram showed that the lower esophagus was compressed within approximately 5.5 cm. Endoscopy revealed the presence of a large submucosal protuberant lesion in the esophagus at a distance of 32-38 cm from the incisors. Endoscopic ultrasound findings demonstrated a 4.5 cm × 5.0 cm hypoechoic lesion. Chest computed tomography revealed a mass of size approximately 53 mm × 39 mm × 50 mm. Initial tests revealed features indicative of leiomyoma. After multidisciplinary discussions, the patient underwent a video-assisted thoracoscopic partial esophagectomy. Further investigation involving immunohistochemical examination confirming palisading spindle cells as positive for S100 and Sox10 led to the final diagnosis of a lower esophageal schwannoma. There was no tumor recurrence or metastasis during follow-up.

CONCLUSION

The final diagnosis of esophageal schwannoma requires histopathological and immunohistochemical examination. The early appropriate surgery favors a remarkable prognosis.

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

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

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.

Stent placement to prevent strictures after esophageal endoscopic submucosal dissection: a systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) is an important method for the treatment of early esophageal cancer. However, post-procedure stenosis is one of the most common long-term complications. This meta-analysis aimed to investigate whether stent placement is effective in the stenosis prevention, and which type of stent would be more effective. A systematic and electronic search of clinical trials and observational studies conducted before March 2020 on the efficacy of stent placement in preventing esophageal stricture after ESD was performed. Search terms included "ESD," "esophageal stenosis," "esophageal stricture," and "stents." We conducted a bias risk assessment of the eligible reports and a meta-analysis of the data using Revman 5.3 software. We included two randomized controlled trials (RCTs) and a prospective cohort study involving 163 patients with esophageal mucosal defects encompassing at least three-quarters of the esophagus circumference after ESD. The meta-analysis results showed that post-ESD stenosis rates (RR, 0.37; 95% CI, 0.22-0.64; P = 0.0003) and the number of endoscopic balloon dilations (EBDs) (MD, -1.74; 95% CI, -2.46 to -1.01; P < 0.00001) were reduced in the pooled analysis of three studies, indicating that stent placement was effective for stenosis prevention, especially a polyglycolic acid (PGA) sheet combined with stent placement can prevent stenosis (RR, 0.41; 95% CI, 0.23-0.74; P = 0.003) and reduce the number of EBDs (MD, -1.65; 95% CI, -2.40 to -0.90; P < 0.0001) significantly. Stent placement can reduce the rate of esophageal stenosis after ESD, especially when stents are covered with PGA sheets. However, more high-quality, low-bias RCTs with a sufficient sample size are needed to demonstrate its effectiveness.

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.

Development of a prognostic prediction model based on microRNA-1269a in esophageal cancer

BACKGROUND

Esophageal cancer (ESCA) is a heterogeneous cancer with variable outcomes that are challenging to predict. MicroRNA (miR)-1269a is a newly discovered non-coding RNA that shows promising prognostic prediction in other cancers, but its clinical value in ESCA remains unclear.

AIM

To explore the relationship between miR-1269a and its clinical value and to develop a nomogram to succinctly display this relationship.

METHODS

We analyzed the expression of miR-1269a in 125 ESCA tissue samples with complete clinical data and 52 normal tissue samples. We determined the prognostic value of miR-1269a for overall survival (OS) and cancer-specific survival (CSS) and evaluated the association between miR-1269a and clinical variables including tumor location, histologic grade, metastatic stage, and American Joint Committee on Cancer (AJCC) stage using multivariate Cox analysis. Additionally, we developed a nomogram for OS and CSS based on miR-1269a expression using age and AJCC stage and assessed its prognostic performance. Using Gene Ontology and Kyoto Encyclopedia of Gene and Genomes analyses, we predicted the target genes of miR-1269a and analyzed their potential function in caner development.

RESULTS

The expression of miR-1269a was significantly higher in ESCA patients than healthy controls. Patients with high expression of miR-1269a showed poor prognosis in OS and CSS, suffered increased rates of low differentiation and metastasis, and exhibited tumor stage T3 + T4, positive lymph stage, and AJCC stage III + IV. The area under the receiver operating characteristic curve of miR-1269a was 0.716 for OS and 0.764 for CSS. Multivariate Cox analysis revealed that AJCC stage and miR-1269a were independent factors for OS and CSS. Combing with age, we constructed a nomogram for prognostic prediction. Additionally, our nomogram showed excellent predictive performance for OS and CSS after 3 years and 5 years and was easy to use. Ultimately, the functional analysis suggested that miR-1269a was mostly involved in the PI3K-AKT signaling pathway.

CONCLUSION

miR-1269a can be used as a potential indicator for the prognosis of ESCA patients. We developed an easy-to-use nomogram with excellent ESCA prognostic prediction for clinical use.

What About Gastric Schwannoma? A Review Article

PURPOSE

Gastric schwannomas (GSs) are rare mesenchymal neoplasms of the gastrointestinal tract. Diagnosis is often achieved postoperatively, based on pathology reports of retrieved specimens. The aim of the present study is to follow up all patients with gastric schwannoma (Gs) undergoing endoscopic, partial, or more extended surgery and to evaluate the appearance of local or distant recurrence.

METHODS

A PubMed, Cochrane, and Embase systematic review of the literature has been performed. Original papers, review articles, and case reports published between 1988 and 2019 were considered eligible. All the studies who met the inclusion criteria were analyzed. Statistical analysis of data has been performed using GraphPad Prism 7 software.

RESULTS

Three hundred twenty-eight articles were found, and a total of 102 were included and analyzed in depth. Fifty-three papers reported the follow-up information, ranging from 1 to 417 months across different studies. Among them, 31 patients underwent endoscopic removal of the gastric lesions; 140 patients underwent local surgery, including wedge resection or partial gastrectomy; and 148 patients underwent subtotal or total gastrectomy. The median follow-up was of 27-38-33 months, respectively. No recurrence or distant metastasis was detected in the endoscopy group. Among local surgery group, liver metastasis was reported in one case; in extended surgery group, one patient died for multiple liver metastases.

CONCLUSIONS

Local or more extended surgery involved a larger cohort of patients and reported satisfactory long-term results compared with endoscopy group. Surgery in absence of a definite preoperative diagnosis is considered the gold standard treatment for resectable Gs.

The Asian Federation of Societies for Ultrasound in Medicine and Biology (AFSUMB) Guidelines for Contrast-Enhanced Endoscopic Ultrasound

The Asian Federation of Societies for Ultrasound in Medicine and Biology aimed to provide information on techniques and indications for contrast-enhanced harmonic endoscopic ultrasound (CH-EUS), and to create statements including the level of recommendation. These statements are based on current scientific evidence reviewed by a Consensus Panel of 15 internationally renowned experts. The reliability of clinical questions was measured by agreement rates after voting. Six statements were made on techniques, including suitable contrast agents for CH-EUS, differences between contrast agents, setting of mechanical index, dual imaging and duration and phases for observation. Thirteen statements were made on indications, including pancreatic solid masses, pancreatic cancer staging, pancreatic cystic lesions and mural nodules, detection of subtle pancreatic lesions, gallbladder sludge and polyps, hepatic lesions, lymph nodes, subepithelial lesions, visceral vascular diseases, guidance of fine needle aspiration and evaluation for local therapy. These international expert consensus guidelines will assist endosonographers in conducting CH-EUS according to evidence-based information.

Advances in The Diagnosis and Treatment of Achalasia of The Cardia: a Review

Idiopathic achalasia is an esophageal motor disorder characterized by the loss of the lower esophageal sphincter ganglion, resulting in impaired lower esophageal relaxation and absence of esophageal peristalsis. Patients commonly present with progressive dysphagia accompanied by reflux, heartburn, retrosternal pain, and severe weight loss. Diagnosis is primarily based on the patient's chief complaints, barium esophagography, and the most recent high-resolution manometry. Endoscopic assessment and endoscopic ultrasonography also have significant value with regard to the exclusion of esophageal anatomical lesions, neoplastic diseases, and pseudoachalasia. However, as most patients with achalasia demonstrate a gradual onset, early diagnosis is difficult. Currently, treatment of idiopathic achalasia, including pneumatic dilation, stent placement, and surgical myotomy, is aimed at reducing lower esophageal sphincter pressure and relieving the symptoms of dysphagia. Peroral endoscopic myotomy has gradually become the mainstream treatment because it causes less trauma and has a rapid recovery rate. This article reviews the main methods of diagnosis and treatment of achalasia, with an emphasis on the potential of peroral endoscopic myotomy and the advancements of immunotherapy for achalasia.

Endoscopic full-thickness resection using an over-the-scope device: A prospective study

BACKGROUND

Endoscopic submucosal dissection to treat mucosal and submucosal lesions sometimes results in low rates of microscopically margin-negative (R0) resection. Endoscopic full-thickness resection (EFTR) has a high R0 resection rate and allows for the definitive diagnosis and treatment of selected mucosal and submucosal lesions that are not suitable for conventional resection techniques.

AIM

To evaluate the efficacy and safety of EFTR using an over-the-scope clip (OTSC).

METHODS

This prospective, single-center, non-randomized clinical trial was conducted at the endoscopy center of Shengjing Hospital of China Medical University. The study included patients aged 18-70 years who had gastric or colorectal submucosal tumors (SMTs) (≤ 20 mm in diameter) originating from the muscularis propria based on endoscopic ultrasound (EUS) and patients who had early-stage gastric or colorectal cancer (≤ 20 mm in diameter) based on EUS and computed tomography. All lesions were treated by EFTR combined with an OTSC for wound closure between November 2014 and October 2016. We analyzed patient demographics, lesion features, histopathological diagnoses, R0 resection (negative margins) status, adverse events, and follow-up results.

RESULTS

A total of 68 patients (17 men and 51 women) with an average age of 52.0 ± 10.5 years (32-71 years) were enrolled in this study, which included 66 gastric or colorectal SMTs and 2 early-stage colorectal cancers. The mean tumor diameter was 12.6 ± 4.3 mm. The EFTR procedure was successful in all cases. The mean EFTR procedure time was 39.6 ± 38.0 min. The mean OTSC defect closure time was 5.0 ± 3.8 min, and the success rate of closure for defects was 100%. Histologically complete resection (R0) was achieved in 67 (98.5%) patients. Procedure-related adverse events were observed in 11 (16.2%) patients. The average post-procedure length of follow-up was 48.2 ± 15.7 mo. There was no recurrence during follow-up.

CONCLUSION

EFTR combined with an OTSC is an effective and safe technique for the removal of select subepithelial and epithelial lesions that are not amenable to conventional endoscopic resection techniques.

Controversies in EUS: Do we need miniprobes?

This is the fifth in a series of papers entitled "Controversies in EUS." In the current paper, we deal with high-resolution catheter probes, otherwise known as EUS miniprobes (EUS-MPs). The application of miniprobes for early carcinomas in the entire intestinal tract, for subepithelial lesions, and for findings in the bile duct and pancreatic duct as well as endobronchial use is critically discussed. Submucous lesions, especially in the colon, but also early carcinomas in special cases are considered the most important indications. The argument is illustrated by numerous examples.

Endoscopic fenestration in the diagnosis and treatment of delayed anastomotic submucosal abscess: A case report and review of literature

BACKGROUND

Abscess formation is one of the complications after radical resection of rectal cancer; cases with delayed postoperative anastomotic abscess are rare. Here, we report a rare case of postoperative anastomotic abscess with a submucosal neoplasm appearing after rectal surgery. Ultimately, the patient was diagnosed and treated by endoscopic fenestration. In addition, we review the literature on the appearance of an abscess as a complication after rectal cancer surgery.

CASE SUMMARY

A 57-year-old man with a history of rectal malignancy resection complained of a smooth protuberance near the anastomotic stoma. Endoscopic ultrasonography revealed a hypoechoic structure originating from the muscularis propria, and a submucosal tumor was suspected. The patient was subsequently referred to our hospital and underwent pelvic contrast-enhanced computed tomography, which revealed no thickening or strengthening of the anastomotic wall. In order to clarify the origin of the lesion and obtain the pathology, endoscopic fenestration was performed. After endoscopic procedure, a definitive diagnosis of delayed anastomotic submucosal abscess was established. The patient achieved good recovery and prognosis after the complete clearance of abscess.

CONCLUSION

Endoscopic fenestration may be safe and effective for the diagnosis/treatment of delayed intestinal smooth protuberance after rectal cancer surgery.

Endoscopic resection of benign esophageal schwannoma: Three case reports and review of literature

BACKGROUND

Esophageal schwannomas are uncommon esophageal submucosal benign tumors and are usually treated with surgery.

CASE SUMMARY

Here, we report three cases of middle/lower thoracic esophageal schwannoma treated successfully with endoscopic resection. These lesions were misdiagnosed as leiomyoma on preoperative imaging. During the endoscopic resection of such tumors, there is a risk of esophageal perforation due to their deep location. If possible, submucosal tunneling endoscopic resection should be used.

CONCLUSION

For larger schwannomas, endoscopy combined with thoracoscopy can be considered for en bloc resection. We performed a mini literature review in order to present the current status of diagnosis and treatment for esophageal schwannoma.

Clinicopathological features of esophageal schwannomas in mainland China: systematic review of the literature

OBJECTIVE

Esophageal schwannoma (ES) are rare and mostly benign neurogenic tumors. The clinical misdiagnosis rate of it is high. In this study, the clinicopathologic features of ES in mainland China were studied to better understand the disease and improve the diagnosis and treatment rate.

METHODS

A systematic review was conducted in accordance with PRISMA guidelines. The keywords "esophageal schwannoma", "esophageal neurinoma" and "esophageal neurilemoma" were searched for databases such as Pubmed, EMbase, Wanfang Database and Chinese National Knowledge Infrastructure. The search time frame for database was until July 2019. Combined with our patient, the clinicopathological data and the diagnosis and treatment of ES were summarized.

RESULTS

ES occurs in the upper part of the mediastinum and in the thoracic esophagus in most patients in the neck, upper and middle segments. CT and PET/CT examinations can be used for diagnosis, but the differentiation value of both benign and malignant ES is similar. The histopathological findings of forceps biopsy specimens are often difficult to diagnose, and deep tissue biopsies may increase pathological accuracy. EUS-FNA is also recommended for ES diagnosis, but it may also be misdiagnosed. Pathological features include a fusiform arrangement in a palisade-like structure or a tumor cell arranged in a network to form a loose structure. ES characteristic immunohistochemistry results showed that S-100 protein has strong immunological activity.

CONCLUSION

The definitive diagnosis requires immunohistochemistry, especially immunological reaction with S-100 protein. The appropriate treatment plan should be selected according to the diameter of the lesion. The overall prognosis of ES is good, but attention should be paid to follow-up.

A scoring model for radiologic diagnosis of gastric leiomyomas (GLMs) with contrast-enhanced computed tomography (CE-CT): Differential diagnosis from gastrointestinal stromal tumors (GISTs)

OBJECTIVES

To investigate CT findings and develop a diagnostic score model to differentiate GLMs from GISTs.

METHODS

This retrospective study included 109 patients with pathologically confirmed GLMs (n = 46) and GISTs (n = 63) from January 2013 to August 2018 who received CE-CT before surgery. Demographic and radiological features was collected, including lesion location, contour, presence or absence of intralesional necrosis and ulceration, growth pattern, whether the tumor involved EGJ, the long diameter (LD) /the short diameter (SD) ratio, pattern and degree of lesion enhancement. Univariate analyses and multivariate logistic regression analyses were performed to identify independent predictors and establish a predictive model. Independent predictors for GLMs were weighted with scores based on regression coefficients. A receiver operating characteristic (ROC) curve was created to determine the diagnostic ability of the model. Overall score distribution was divided into four groups to show differentiating probability of GLMs from GISTs.

RESULTS

Five CT features were the independent predictors for GLMs diagnosis in multivariate logistic regression analysis, including esophagogastric junction (EGJ) involvement (OR, 367.9; 95 % CI, 5.8-23302.8; P =  0.005), absence of necrosis (OR, 11.9; 95 % CI, 1.0-138. 1; P =  0.048) and ulceration (OR, 151.9; 95 % CI, 1.4-16899.6; P =  0.037), degree of enhancement (OR, 9.3; 95 % CI, 3.2-27.4; P <  0.001), and long diameter/ short diameter (LD/SD) ratio (OR,170.9; 95 % CI, 8.4-3493.4; P =  0.001). At a cutoff of 9 points, AUC for this score model was 0.95, with 95.65 % sensitivity, 79.37 % specificity, 77.19 % PPV, 96.15 % NPV and 86.24 % diagnostic accuracy. An increasing trend was showed in diagnostic probability of GLMs among four groups based on the score (P <  0.001).

CONCLUSIONS

The newly designed scoring system is reliable and easy-to-use for GLMs diagnosis by distinguishing from GISTs, including EGJ involvement, absence of ulceration and necrosis, mild enhancement and high LD/SD ratio. The overall score of model ranged from 1 to 17 points, which was divided into 4 groups: 1-7 points, 7-10 points, 10-13 points and 13-17 points, with a diagnostic probability of GLMs 0%, 45 %, 83 % and 100 %, respectively.

Endoscopic ultrasound-measured muscular thickness of the lower esophageal sphincter and long-term prognosis after peroral endoscopic myotomy for achalasia

BACKGROUND

People with achalasia typically have a thick lower esophageal muscularis propria (LEMP), and peroral endoscopic myotomy (POEM) has been effective in treating most patients. LEMP thickness may be associated with the outcomes and prognosis after POEM. However, more evidence is needed regarding the relationship between LEMP thickness and patient prognosis after POEM.

AIM

To assess the association between LEMP thickness, measured using endoscopic ultrasound (EUS), and long-term prognosis, especially relapse, after POEM for achalasia.

METHODS

All medical records, including EUS data, of patients who underwent POEM to treat achalasia at Shengjing Hospital of China Medical University from January 2012 to September 2018 were retrospectively reviewed. LEMP thickness was measured by EUS, and a thickness of ≥ 3 mm was defined as thickened. The severity of patient symptoms was evaluated using the Eckardt score. Relapse was defined as a 3-point rise in the Eckardt score after a period of clinical remission. The relationship between patient characteristics, muscle thickness, and recurrence was analyzed.

RESULTS

Eighty-two patients (32 males and 50 females, aged 17-78 years) and 85 POEM procedures were included. In total, 76.8% (63/82 patients) of patients had a thickened muscularis propria. Older age and longer disease course were associated with muscularis propria thickening (P < 0.05). The mean postoperative follow-up time was 35.4 ± 17.2 mo (range, 8-87.5 mo) in 60 patients. Five patients with Eckardt scores > 3 refused further management after their symptoms were relieved. The relapse rate was 12.73% (7/55 cases). Five patients, four of whom had muscularis propria thickening, had disease recurrence within 12 mo after the procedure. Achalasia relapsed in one patient who had a thickened muscularis propria after 24 mo and in another patient who did not have a thickened muscularis propria after 30 mo. Patients with recurrence were typically younger and had a shorter disease course (P < 0.05). The relapse rate in patients with a non-thickened muscularis propria tended to be higher (18.2%, 2/11 patients) than that in patients with a thickened muscularis propria (11.4%, 5/44 patients), although no significant difference was found. Age (hazard ratio = 0.92; 95% confidence interval: 0.865-0.979; P < 0.05) and being male (hazard ratio = 7.173; 95% confidence interval: 1.277-40.286; P < 0.05) were identified as risk factors for symptomatic recurrence by multivariable analysis using the Cox model.

CONCLUSION

Patients with a thickened muscularis are typically older and have a longer disease course. Younger age and the male sex are associated with increased recurrence. Patients with a thin muscularis propria may be prone to relapse, although further validation is needed.

Advances in the Prevention and Treatment of Esophageal Stricture after Endoscopic Submucosal Dissection of Early Esophageal Cancer

Endoscopic submucosal dissection (ESD) has become the main treatment for early esophageal cancer. While treating the disease, ESD may also cause postoperative esophageal stricture, which is a global issue that needs resolution. Various methods have been applied to resolve the problem, such as mechanical dilatation, glucocorticoids, anti-scarring drugs, and regenerative medicine; however, no standard treatment regimen exists. This article describes and evaluates the strengths and limitations of new and promising potential strategies for the treatment and prevention of esophageal strictures.

Bibliometric analysis of subject trends and knowledge structures of gut microbiota

BACKGROUND

Gut microbiota is an emerging field of research, with related research having breakthrough development in the past 15 years. Bibliometric analysis can be applied to analyze the evolutionary trends and emerging hotspots in this field.

AIM

To study the subject trends and knowledge structures of gut microbiota related research fields from 2004 to 2018.

METHODS

The literature data on gut microbiota were identified and downloaded from the PubMed database. Through biclustering analysis, strategic diagrams, and social network analysis diagrams, the main trend and knowledge structure of research fields concerning gut microbiota were analyzed to obtain and compare the research hotspots in each period.

RESULTS

According to the strategic coordinates and social relationship network map, Clostridium Infections/microbiology, Clostridium Infections/therapy, RNA, Ribosomal, 16S/genetics, Microbiota/genetics, Microbiota/immunology, Dysbiosis/immunology, Infla-mmation/immunology, Fecal Microbiota Transplantation/methods, Fecal Microbiota Transplantation can be used as an emerging research hotspot in the past 5 years (2014-2018).

CONCLUSION

Some subjects were not yet fully studied according to the strategic coordinates; and the emerging hotspots in the social network map can be considered as directions of future research.

Direct endoscopic full-thickness resection for submucosal tumors with an intraluminal growth pattern originating from the muscularis propria layer in the gastric fundus

Background and aims

Endoscopic full-thickness resection (EFTR) is difficult to perform in a retroflexed fashion in the gastric fundus. The present study aims at exploring whether direct EFTR can be a simple, effective and safe procedure to treat intraluminal-growth submucosal tumors originating from the muscularis propria.

Methods

The patients with intraluminal-growth submucosal tumors originating from the muscularis propria in gastric fundus treated by direct EFTR between 01 January 2017 and 01 September 2018 were retrospectively reviewed. In addition, we analyzed the patients with intraluminal-growth submucosal tumors originating from the muscularis propria in gastric fundus treated by traditional EFTR. The differences in tumor resection time, cost-effectiveness, and complication rate were evaluated.

Results

Forty patients were enrolled in the present study, 20 patients of which were in the direct EFTR group and 20 patients of which were in the traditional EFTR group. En-bloc resections of gastric tumors were successfully performed in all 40 cases. There was no significant difference in the average tumor size of the two groups (24.3 ± 2.9 mm in direct EFTR group verus 24.0 ± 2.6 mm in the traditional group, p = 0.731), but significant difference existed in the operative time between two groups (35.0 ± 8.2 min in direct EFTR group verus 130.6 ± 51.9 min in the traditional group, p<0.05). No complications, such as postoperative bleeding and perforation, occurred in any groups.

Conclusions

Direct EFTR is a safe, simple and cost-effective procedure for SMTs with an intraluminal growth pattern originating from the muscularis propria layer in the gastric fundus.

The Role of Endoscopic Ultrasound and Endoscopic Resection for Gastric Glomus: A Case Series and Literature Review

Background and Objectives

Preoperative diagnosis of gastric glomus tumor is very difficult, and there are few reports regarding the endoscopic treatment of glomus tumor of the stomach. Our aim is to provide a retrospective assessment of the imaging features of endoscopic ultrasound (EUS) and treatment of choice of gastric glomus tumor.

Methods

A database of all patients with gastric glomus tumor who was treated at Shengjing Hospital of China Medical University between March 2011 and March 2017 was retrospectively analyzed. The EUS characteristics and patients’ clinical data as well as their treatment were reviewed. At the same time, we compared EUS characteristics of gastric glomus tumor with that of gastrointestinal stromal tumor (GISTs), leiomyomas, schwannomas, and ectopic pancreas.

Results

Eleven patients (3 male and 8 female patients) were included in the present study. The patients’ age ranged from 37 to 62 years (mean age, 50.1 years). Ten patients received EUS examination. Eight lesions were presented with mild-hyperechoic round or oval mass; one lesion was mild-hyperechoic oval mass with hypoechoic spots; one lesion was hypoechoic oval mass. One patient received endoscopic full-thickness resection; 3 patients were treated by endoscopic submucosal dissection; and laparoscopic resection was performed for 7 patients.

Conclusions

Gastric glomus has typical EUS features to differentiate from other submucosal tumors. Compared with surgery, endoscopic resection is also a safe and effective treatment of choice for gastric glomus tumor.

Endoscopic full-thickness resection for treating small tumors originating from the muscularis propria in the gastric fundus: An improvement in technique over 15 years

BACKGROUND

The fundus of the stomach is regarded as a difficult area for endoscopic resection of small tumors originating from the muscularis propria (MP tumors). Three endoscopic resection techniques have been developed to treat these tumors, including ligation-assisted endoscopic full-thickness resection (L-EFTR), snare-assisted EFTR (S-EFTR), and endoscopic submucosal dissection-assisted EFTR (E-EFTR). To date, no studies have compared these techniques.

AIM

We aimed to evaluate and compare S-EFTR with L-EFTR and E-EFTR for treating small MP tumors in the gastric fundus.

METHODS

We retrospectively reviewed patients with primary small MP tumors in the gastric fundus and treated by these three techniques between January 2016 and December 2018 at Shengjing Hospital, China. Standard demographic and clinicopathologic data, including sex, age, tumor size, surgeon details, and pathological results, were collected. Data regarding operation duration, cost, en-bloc resection, and severe complications were also extracted and compared.

RESULTS

A total of 36 patients (27 women) with a mean age of 55.8 ± 10.20 years were included in this study. The mean tumor size was 9.0 ± 3.98 mm. All the methods showed a 100% en-bloc resection rate and 0% severe complication rate. There was no statistically significant difference among the three groups in the operation duration (P = 0.148). The cost comparison for the whole procedure was as follows: E-EFTR > L-EFTR > S-EFTR (5837.5 ± 7212.96 CNY, 5970.7 ± 3465.27 CNY, 5852.0 ± 6438.25 CNY, respectively, P < 0.001).

CONCLUSION

S-EFTR, L-EFT, and E-EFTR are all effective for resection of small MP tumors in the gastric fundus. S-EFTR is superior in terms of cost-effectiveness.

Contrast Enhanced Endoscopic Ultrasound Imaging for Gastrointestinal Subepithelial Tumors

Subepithelial tumors are divided into benign subepithelial and potentially malignant gastrointestinal stromal tumors. It is difficult to distinguish between these tumor types. Contrast-enhanced harmonic endoscopic ultrasound is reportedly useful for diagnosing subepithelial tumors, can be safely and easily performed by understanding the principle and method, and can be used to distinguish between tumor types with high sensitivity on the basis of differences in contrast effect. The generated image shows a hyperenhancement pattern in gastrointestinal stromal tumors (sensitivity, 78%-100%; specificity, 60%-100%; accuracy, 60%-100%) and hypoenhancement pattern in benign subepithelial tumors. Contrast-enhanced harmonic endoscopic ultrasound can be used to estimate the malignancy potential of gastrointestinal stromal tumors by evaluating the uniformity of the contrast and the blood vessels inside the tumor, with abnormal intra-tumor blood vessels, heterogeneous enhancement, and non-enhancing spots suggesting malignancy. Contrast-enhanced harmonic endoscopic ultrasound has a higher sensitivity than other imaging modalities for the detection of vascularity within gastrointestinal stromal tumors. Additionally, it has been reported that treatment effects can be estimated by evaluating the blood flow in the gastrointestinal stromal tumor before and after treatment with tyrosine kinase inhibitors using contrastenhanced ultrasound. However, there will be subjective-bias and the results depends on the performer's skill.