Ligation-assisted endoscopic submucosal resection following unroofing technique for small esophageal subepithelial lesions originating from the muscularis propria

BACKGROUND The majority of esophageal subepithelial lesions originating from the muscularis propria(SEL-MPs)are benign in nature,although a subset may exhibit malignant characteristics.Conventional endoscopic resection techniques are time-consuming and lack efficacy for small SEL-MPs.AIM To evaluate the efficacy and safety of ligation-assisted endoscopic submucosal resection(ESMR-L)following unroofing technique for small esophageal SEL-MPs.METHODS From January 2021 to September 2023,17 patients diagnosed with esophageal SEL-MPs underwent ESMR-L following unroofing technique at the endoscopy center of Shenzhen People’s Hospital.Details of clinicopathological characteristics and clinical outcomes were collected and analyzed.RESULTS The mean age of the patients was 50.12±12.65 years.The mean size of the tumors was 7.47±2.83 mm and all cases achieved en bloc resection successfully.The average operation time was 12.2 minutes without any complications.Histopathology identified 2 Lesions(11.8%)as gastrointestinal stromal tumors at very low risk,12 Lesions(70.6%)as leiomyoma and 3 Lesions(17.6%)as smooth muscle proliferation.No recurrence was found during the mean follow-up duration of 14.18±9.62 months.CONCLUSION ESMR-L following roofing technique is an effective and safe technique for management of esophageal SEL-MPs smaller than 20 mm,but it cannot ensure en bloc resection and may require further treatment.

Corneal subepithelial nerve fibers in type 2 diabetes:potential biomarker of diabetic neuropathy

AIM:To observe the changes in corneal subepithelial nerve fibers(CNFs)and Langerhans cells(LCs)in patients with type 2 diabetes using corneal laser confocal microscopy(CLCM).METHODS:A total of 60 patients(64 eyes),including 40 patients with type 2 diabetes(DM group)and 20 subjects without diabetes(control group)were included with CLCM.Neuron J plugin of Image J software were used for quantitative analysis of CNF length(CNFL),CNF density(CNFD),corneal nerve branch fiber density(CNBD),main branch length density,branch length density,corneal nerve fiber tortuosity(NT)score,and LCs density.An independent samples t-test to analyze the variability between the two groups was performed,and Pearson correlation analysis was used to analyze the relationships between CNF and multiple biochemical indicators in the DM group.The predictive power of CNF for type 2 diabetes was assessed using the receiver operating characteristic(ROC)curve.RESULTS:There were significant differences in the CNFL,CNFD,and main branch length density between two groups.The results of Pearson correlation analysis showed a significant negative correlation between CNFD and the duration of diabetes as well as triglyceride levels and total cholesterol,and a significant positive correlation between CNFD and serum albumin.In addition,the NT score showed a positive correlation and urea nitrogen,similar to the positive correlation observed between LC density and glycosylated hemoglobin(HbA1c)levels.CNFD showed the highest area under the curve(AUC of ROC)value,followed by main branch length density and CNFL.The AUC of the ROC curve under the logistic regression model also demonstrated good predictive values.The cut-off values of CNFD,CNFL,and main branch length density for diabetes showed 31.25,18.85,and 12.56,respectively.CONCLUSION:In patients with type 2 diabetes,there is a notable reduction in both CNFL and CNFD.These measurements can be influenced by various blood biochemical factors.However,the compromised nerve fibers can serve as valuable indicators for predicting the onset of type 2 diabetes and also as biomarkers for detecting diabetic neuropathy and its related complications.

The efficacy of full-thickness endoscopic resection of subepithelial tumors in the gastric cardia

BACKGROUND Gastric subepithelial tumors(SETs)may harbor potential malignancy.Although it is well recognized that large SETs should be resected,the precise treatment strategy remains controversial.Compared to surgical resection,endoscopic resection(ER)has many advantages;however,ER of SETs in the cardia is challenging.AIM To evaluate the safety and efficacy of endoscopic full-thickness resection(EFTR)for the treatment of gastric cardia SETs.METHODS We retrospectively reviewed data from all patients with SETs originating from the muscularis propria layer in the gastric cardia that were treated by EFTR or submucosal tunneling ER(STER)at Zhongshan Hospital Fudan University between November 2014 and May 2022.Baseline characteristics and clinical outcomes,including procedure times and complications rates,were compared between groups of patients receiving EFTR and STER.RESULTS A total of 171 tumors were successfully removed[71(41.5%)tumors in the EFTR and 100(58.5%)tumors in the STER group].Gastrointestinal stromal tumors(GISTs)were the most common SET.The en bloc resection rate was 100%in the EFTR group vs 97.0%in STER group(P>0.05).Overall,the EFTR group had a higher complete resection rate than the STER group(98.6%vs 91.0%,P<0.05).The procedure time was also shorter in the EFTR group(44.63±28.66 min vs 53.36±27.34,P<0.05).The most common major complication in both groups was electrocoagulation syndrome.There was no significant difference in total complications between the two groups(21.1%vs 22.0%,P=0.89).CONCLUSION EFTR of gastric cardia SETs is a very promising method to facilitate complete resection with similar complications and reduced operative times compared to STER.In cases of suspected GISTs or an unclear diagnosis,EFTR should be recommended to ensure complete resection.

Goldilocks principle of minimally invasive surgery for gastric subepithelial tumors

BACKGROUND Minimally invasive surgery had been tailored to individual cases of gastric subepithelial tumors(SETs)after comparing the clinical outcomes of endoscopic resection(ER),laparoscopic resection(LR),and hybrid methods.AIM To study the use of Goldilocks principle to determine the best form of minimally invasive surgery for gastric SETs.METHODS In this retrospective study,194 patients of gastric SETs with high probability of surgical intervention were included.All patients underwent tumor resection in the operating theater between January 2013 and December 2021.The patients were divided into two groups,ER or LR,according to the tumor characteristics and the initial intent of intervention.Few patients in the ER group required further backup laparoscopic surgery after an incomplete ER.The patients who had converted open surgery were excluded.A logistic regression model was used to assess the associations between patient characteristics and the likelihood of a treatment strategy.The area under the curve was used to assess the discriminative ability of tumor size and Youden’s index to determine the optimal cut-off tumor size.RESULTS One-hundred ninety-four patients(100 in the ER group and 94 in the LR group)underwent tumor resection in the operating theater.In the ER group,27 patients required backup laparoscopic surgery after an incomplete ER.The patients in the ER group had small tumor sizes and shorter procedure durations while the patients in the LR group had large tumor sizes,exophytic growth,malignancy,and tumors that were more often located in the middle or lower third of the stomach.Both groups had similar durations of hospital stays and a similar rate of major postoperative complications.The patients in the ER group who underwent backup surgery required longer procedures(56.4 min)and prolonged stays(2 d)compared to the patients in the LR group without the increased rate of major postoperative complications.The optimal cut-off point for the tumor size for laparoscopic surgery was 2.15 cm.CONCLUSION Multidisciplinary teamwork leads to the adoption of different strategies to yield efficient clinical outcomes according to the tumor characteristics.

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 EUSFNA should be obtained when possible.Therefore,EUSFNA 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

Endoscopic treatments for small gastric subepithelial tumors originating from muscularis propria layer

Minimally invasive endoscopic resection has become an increasingly popular method for patients with small(less than 3.5 cm in diameter) gastric subepithelial tumors(SETs) originating from the muscularis propria(MP) layer. Currently, the main endoscopic therapies for patients with such tumors are endoscopic muscularis excavation, endoscopic full-thickness resection, and submucosal tunneling endoscopic resection. Although these endoscopic techniques can be used for complete resection of the tumor and provide an accurate pathological diagnosis, these techniques have been associated with several negative events, such as incomplete resection, perforation, and bleeding. This review provides detailed information on the technical details, likely treatment outcomes, and complications associated with each endoscopic method for treating/removing small gastric SETs that originate from the MP layer.

Gastric subepithelial lesion complicated with abscess: Case report and literature review

Gastric abscess is a localized pyogenic inflammation of the gastric wall, which is a rare form of suppurative gastritis. The rarity of gastric abscess may be associated with the difficulty of early diagnosis and high mortality as a result. In general, subepithelial lesions (SELs) of the stomach are incidentally detected during the course of upper endoscopy without specific clinical symptoms and signs. However, some gastric SELs present rarely as a form of hemorrhage, obstruction, perforation, and abscess. Here we report a 45-year-old man with gastric SEL presenting as a gastric abscess, which was diagnosed as an ectopic pancreas of the stomach, along with a review of the literature. Although gastric SEL presenting as an abscess is known as a serious and life-threatening lesion, the patient made a complete recovery through surgical resection as well as medical treatment.

Esophageal subepithelial lesion diagnosed as malignant gastrointestinal neuroectodermal tumor

A 21-year-old male visited our hospital with a complaint of aggravating dysphagia and odynophagia for a few days.Esophagogastroduodenoscopy showed huge bulging mucosa with an intact surface causing luminal narrowing at 35 cm from the incisor teeth.Endoscopic ultrasonography showed an about 35 mm sized irregular margined in-homogenous hypoechoic lesion with an obscure layer of origin.Endoscopic ultrasonography fine needle aspiration revealed spindle cell proliferation without immunoreactivity for CD117,SMA,and cytokeratin.The patient underwent excision of the subepithelial lesion at the distal esophagus.On pathologic examination of the specimen,the tumor was composed of short fascicles of oval to spindle cells with eosinophilic and clear cytoplasm and vesicular nuclei.The tumor cells were positive for S-100 and SOX10and negative for CD117,SMA,HMB-45,melan-A,cytokeratin,and CD99.The split-apart signal was detected in EWSR1 on FISH,suggesting a malignant gastrointestinal neuroectodermal tumor.At the time of writing,the patient is on radiation therapy at the operated site of esophagus and doing well,with no recurrence for three months.Malignant gastrointestinal neuroectodermal tumor is a rare gastrointestinal tumor with features of clear cell sarcoma,without melanocytic differentiation,and shows a poor prognosis.This is the first reported case of malignant gastrointestinal neuroectodermal tumor arising as subepithelial lesion in the esophagus.

Clinical course of subepithelial lesions detected on upper gastrointestinal endoscopy

AIM:To evaluate the natural history of subepithelial lesions.METHODS:We reviewed the medical records of 104 159 patients who underwent upper gastrointestinal endoscopy at the Center for Health Promotion of Samsung Medical Center between 1996 and 2003.Subepithelial lesions were detected in 795 patients(0.76%);252 patients were followed using upper gastrointestinal endoscopy for 82.5 ± 29.2 mo(range,12-160 mo;median,84 mo;1st quartile,60 mo;3rd quartile,105 mo).The median interval of follow-up endoscopy was 12 mo(range,6-105 mo;1st quartile,12 mo;3rd quartile,24 mo).RESULTS:The mean patient age was 53 years(range,22-80 years),and the male-to-female ratio was 2.36:1(177/75).The lesion size at initial measurement averaged 8.9 mm(range,2-25 mm;median,8 mm;1st quartile,5 mm;3rd quartile,10 mm).Of the 252 lesions,244(96.8%) were unchanged and 8(3.2%) were significantly increased in size(from 12.9 ± 6.0 to 21.2 ± 12.2 mm) after a mean interval of 59.1 ± 27.5 mo(range,12-86 mo).Surgical resection of lesions was performed when the lesions were ≥ 3 cm in diameter.Two lesions were diagnosed as gastrointestinal stromal tumors with an intermediate or high risk of malignancy and one lesion was classified as a schwannoma.CONCLUSION:Most small subepithelial lesions do not change as shown by endoscopic examination,and regular follow-up with endoscopy may be considered in small,subepithelial lesions,especially lesions < 1 cm in size.

Management of gastric subepithelial tumors:The role of endoscopy

With the wide use of esophagogastroduodenoscopy,the incidence of gastric subepithelial tumor(SET)diagnosis has increased.While the management of large orsymptomatic gastric SETs is obvious,treatment of small(≤3 cm)asymptomatic gastric SETs remains inconclusive.Moreover,the presence of gastrointestinal stromal tumors with malignant potential is of concern,and endoscopic treatment of gastric SETs remains a subject of debate.Recently,numerous studies have demonstrated the feasibility of endoscopic treatment of gastric SETs,and have proposed various endoscopic procedures including endoscopic submucosal dissection,endoscopic muscularis dissection,endoscopic enucleation,endoscopic submucosal tunnel dissection,endoscopic full-thickness resection,and a hybrid approach(the combination of endoscopy and laparoscopy).In this review article,we discuss current endoscopic treatments for gastric SETs as well as the advantages and limitations of this type of therapy.Finally,we predict the availability of newly developed endoscopic treatments for gastric SETs.

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.

Hybrid natural orifice transluminal endoscopic surgery in gastric subepithelial tumors

Diagnosis of gastric subepithelial tumor(SET) has shown a rapid increase worldwide.Although,until now,endoscopic ultrasound guided procedures such as fine needle aspiration have shown relatively high accuracy in diagnosis of SET,the most important modality for diagnosis and treatment of SETs is complete resection such as endoscopic or surgical resection.However,endoscopic resection or laparoscopic wedge resection alone also has some limitations.Endoscopic resection is difficult to perform in cases of gastric SET located within deep portion of the gastric layer or a relatively large(larger than 25 mm diameter).On the other hand,gastric SET in a difficult location,such as the gastroesophageal junction or pyloric ring is challenging for laparoscopic surgical resection.The hybrid natural orifice transluminal endoscopic surgery(NOTES) technique is a combined method,including the advantages of both laparoscopic resection and endoscopic resection for gastric SETs.This method may be performed safely with reasonable operation times,less bleeding,and adequate resection margin and regardless of tumor size.In particular,in the case of a difficult location for resection,such as the esophagogastric junction or pyloric ring,hybrid NOTES is currently believed to be an ideal treatment method.

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 EUSFNB.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.

Effect of 0.05% topical cyclosporine for the treatment of symptomatic subepithelial infiltrates due to adenoviral keratoconjunctivitis

Dear Sir,Iam Yonca A.Akova,MD-from the Department of Ophthalmology,Bayindir Kavaklidere Hospital,Turkey.I wrote this letter to evaluate the efficacy of 0.05%topical cyclosporine A（CsA）eye drops（Restasis Allergan,Irvine,USA）in symptomatic patients with recurrent subepithelial infiltrates（SEIs）due to adenoviral keratoconjunctivitis following steroid eye drops tapering or discontinuation.

A feasible modified biopsy method for tissue diagnosis of gastric subepithelial tumors

AIM: To evaluate the diagnostic yield and safety of a modified technique for the histological diagnosis of subepithelial tumors (SETs). METHODS: A retrospective review of patients who underwent a modified technique for the histological diagnosis of gastric SETs, consisting of a mucosal incision with a fixed flexible snare (MIF) and deep-tissue biopsy under conventional endoscopic view, from January 2012 to January 2013 was performed. Eleven patients with gastric SETs 10-30 mm in diameter and originating from the third or fourth layer on endoscopic ultrasonography were included. RESULTS: The mean age was 59.8 (range, 45-76) years, and 5 patients were male. The mean size of the SETs was 21.8 (range, 11-30) mm. The number of biopsy specimens was 6.3 (range 5-8). The mean procedure time was 9.0 min (range, 4-17 min). The diagnostic yield of MIF biopsies was 90.9% (10/11). The histological diagnoses were leiomyoma (4/11, 36.4%), aberrant pancreas (3/11, 27.3%), gastrointestinal stromal tumors (2/11, 18.2%), an inflammatory fibrinoid tumor (1/11, 9.1%); one result was non-diagnostic (1/11, 9.1%). There were six mesenchymal tumors; the specimens obtained in each case were sufficient for an immunohistochemical diagnosis. There was no major bleeding, but one perforation occurred that was successfully controlled by endoscopic clipping. CONCLUSION: The MIF biopsy was simple to perform, safe, and required a shorter procedure time, with a high diagnostic yield for small SETs.

Duodenal subepithelial hyperechoic lesions of the third layer: Not always a lipoma

Endoscopic ultrasonography is the most accurate procedure for the evaluation of subepithelial lesions. The finding of a homogeneous, hyperechoic, well-delimited lesion, originating from the third layer of the gastrointestinal tract(submucosa) suggests a benign tumor,generally lipoma. As other differential diagnoses have not been reported, echoendoscopists might not pursue a definitive pathological diagnosis or follow-up the patient. This case series aims to broaden the spectrum of differential diagnosis for duodenal hyperechoic third layer subepithelial lesions by providing four different and relevant pathologies with this echoendoscopic pattern.

Endoscopic resection of subepithelial tumors

Management of subepithelial tumors(SETs) remains challenging. Endoscopic ultrasound(EUS) has improved differential diagnosis of these tumors but a definitive diagnosis on EUS findings alone can be achieved in the minority of cases. Complete endoscopic resection may provide a reasonable approach for tissue acquisition and may also be therapeutic in case of malignant lesions. Small SET restricted to the submucosa can be removed with established basic resection techniques. However, resection of SET arising from deeper layers of the gastrointestinal wall requires advanced endoscopic methods and harbours the risk of perforation. Innovative techniques such as submucosal tunneling and full thickness resection have expanded the frontiers of endoscopic therapy in the past years. This review will give an overview about endoscopic resection techniques of SET with a focus on novel methods.

Transperineal core-needle biopsy of a rectal subepithelial lesion guided by endorectal ultrasound after contrast-enhanced ultrasound: A case report

BACKGROUND Rectal subepithelial lesions(SELs) are commonly seen in endoscopic examination, generally manifested as bumps with a smooth surface. Precise preoperative diagnoses for rectal SELs are difficult because abnormal tissues are not easily to be obtained by regular endoscopic forceps biopsy. Traditional guidance modalities of preoperative biopsy, including endoscopic ultrasound, computed tomography, and transabdominal ultrasound, are often unsatisfactory. An updated, safe, and effective biopsy guidance method is required. We herein report a new biopsy guidance modality—endorectal ultrasound(ERUS) combined with contrastenhanced ultrasound(CEUS).CASE SUMMARY A 32-year-old woman complained of a mass inside the rectovaginal space for 9 years, which became enlarged within 1 year. A rectal SEL detected by endoscopy was suspected to be a gastrointestinal stromal tumor or exophytic uterine fibroid. Pathological diagnosis was difficult because of unsuccessful transabdominal core needle biopsy with insufficient tissues, as well as vaginal hemorrhage. A second biopsy was suggested after multiple disciplinary treatment discussion, which referred to a transperineal core needle biopsy(CNB) guided by ERUS combined with CEUS. Adequate samples were procured and rectal gastrointestinal stromal tumor was proved to be the pathological diagnosis. Imatinib was recommended for first-line therapy by multiple disciplinary treatment discussion. After the tumor shrunk, resection of the rectal gastrointestinal stromal tumor was performed through the posterior vaginal wall. Adjuvant therapy was applied and no recurrence or metastasis has been found by the last follow-up on December 13, 2019.CONCLUSION Transperineal CNB guided by ERUS and CEUS is a safe and effective preoperative biopsy of rectal SELs yet with some limitations.

Wedge gastrectomy:Robot-assisted with a hand-sewn repair versus a laparoscopic linear stapler technique for gastric subepithelial tumors

Objective:Minimally invasive surgery has become common in surgical resections of gastric subepithelial tumors.An endostapler technique is simple and easy to perform when cutting the stomach.Gastrotomy using a hand-sewn repair is a new approach for identifying and removing gastric subepithelial tumors,but few studies have evaluated its efficacy.In this study,we demonstrated the safety and effectiveness of this novel technique using a robot-assisted approach.Materials and methods:A retrospective cohorts of all patients who presented with gastric subepithelial tumors and underwent robotic or laparoscopic resection at Ramathibodi Hospital from 2012 to 2018 was reviewed.Surgical outcomes and complications of the robot-assisted approach with a hand-sewn repair were analyzed and compared to those of the laparoscopic linear stapler technique.Results:In total,25 patients were included in this study.Most of the subepithelial tumors were gastrointestinal stromal tumors(17 patients,68%).Ten patients(40%)underwent a robot-assisted procedure with a hand-sewing technique,and 15 patients underwent a laparoscopic linear stapler procedure.Mean tumor size was 3.79±1.35 cm in the robot-assisted procedure with a hand-sewing technique group and 3.52±1.88 cm in the laparoscopic linear stapler procedure group.The former experienced a longer operative time(261±54 vs 144±64 minutes,p<0.001)and a longer time to return to a normal diet(5.7±2.0 vs 4.0±1.4 days,p=0.028).Neither group experienced perioperative complications or mortality.Conclusion:Although the time to return to a normal diet and operative time were significantly longer compared to a laparoscopic procedure using a linear stapler,the robot-assisted approach using a handsewn repair for gastric subepithelial tumors is feasible,effective,and safe.This can be an alternative for the surgical treatment of gastric subepithelial lesions.

Endoscopic Treatment of 14 Cases of Small Subepithelial Lesions in the Gastrointestinal Tract Using a Combined Snare, Long Lucency Cap, and Argon Plasma Coagulation Technique

Subepithelial lesions(SEL)of the digestive tract refer to a series of benign and malignant subepithelial masses that appear smooth or rough under gastrointestinal endoscopy.Endoscopic resection of subepithelial lesions in the digestive tract is widely recognized due to its advantages of minimal trauma and rapid recovery.This paper reports and summarizes the experiences of using the combined snare,long lucency cap,and argon plasma coagulation technique to remove small subepithelial lesions in 14 patients.