Tunneling endoscopic muscularis dissection for subepithelial tumors originating from the muscularis propria of the esophagus and gastric cardia

Submucosal Tunneling Endoscopic Resection for Upper Gastrointestinal Subepithelial Lesions: A Systematic Review and Meta-Analysis

AIM

Submucosal tunneling endoscopic resection (STER) is an advanced endoscopic technique used for the minimally invasive removal of subepithelial lesions of the gastrointestinal (GI) tract. The aim of this study was to evaluate the safety and efficacy of STER for upper gastrointestinal subepithelial lesions.

METHODS

A comprehensive search of major scholar databases (until December 15, 2023) was performed. Complete resection rate was considered the primary outcome. En bloc resection, operation duration, length of stay (LOS), local recurrence, and periprocedural complications were considered secondary outcomes. Random-effects (RE) and fixed-effects (FE) models were used to generate the outcome estimates.

RESULTS

A total of 37 studies and 3795 patients were included. Pooled proportion of complete resection was 99% (95% CI 98.4-99.6%, p < 0.001). En bloc resection was achieved at 87.7% of cases. Overall mean operation duration was 64.2 min, while mean LOS was estimated at 4.93 days. The local recurrence rate was 0.1%. The two most common complications associated with STER were subcutaneous emphysema (5.5%) and pneumothorax (3%).

CONCLUSION

STER is a highly feasible and safe treatment modality for upper GI subepithelial lesions.

Endoscopic removal of gastrointestinal lesions by using third space endoscopy techniques

The concept of submucosal space, or rather the "third space", located between the intact mucosal flap and the muscularis propria layer of the gastrointestinal tract, represents a tunnel that the endoscopist could use to perform interventions in the muscularis propria layer or breech it to enter the mediastinum or the peritoneal cavity without full thickness perforation. The tunnel technique can be used both for the removal of mucosal tumours, called endoscopic submucosal tunnel dissection (ESTD), for the removal of subepithelial tumours (SELs), called submucosal tunnelling endoscopic resection (STER), and for the removal of extra-luminal lesions (for example in the mediastinum or in the rectum), called submucosal tunnelling endoscopic resection for extraluminal tumours (STER-ET). Aim of this updated narrative review, is to summarize the evidences that analyses indications, and outcomes of tunnelling techniques for the treatment of above mentioned lesions.

Efficacy and safety of piecemeal submucosal tunneling endoscopic resection for giant esophageal leiomyoma

BACKGROUND AND AIMS

Giant esophageal leiomyoma usually requires a thoracotomy or thoracoscopic surgery, which is more invasive than an endoscopic treatment. The purpose of this study is to evaluate the efficacy and safety of piecemeal submucosal tunneling endoscopic resection (P-STER) for giant leiomyoma originating from the muscularis propria (MP) layer of the esophagus.

METHODS

This is a retrospective study. Patients with giant esophageal leiomyoma (transverse diameter ≥ 3 cm) who underwent P-STER were enrolled from November 2012 to May 2023. Clinical data and results were investigated.

RESULTS

A total of 16 patients were enrolled for analysis. The lesion mean transverse diameter and longitudinal diameter were 4.22 ± 1.20 cm and 6.20 ± 1.57 cm, respectively. Our mean operation time was 195.38 ± 84.99 min. The mean number of piecemeal resected was 4.31 ± 2.36. An adverse event noted was an esophageal fistula that occurred in one case (6.25%) and was treated conservatively. The mean length of hospital stay was around 11.81 ± 7.30 days. The mean total hospitalization cost was U.S. dollars (USD) $5976.50 ± 2866.39. No recurrence or metastasis was found during the follow-up period.

CONCLUSIONS

P-STER can be an effective and safe treatment for giant leiomyoma originating from the MP layer of the esophagus.

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.

Total removal of a large esophageal schwannoma by submucosal tunneling endoscopic resection: A case report and review of literature

BACKGROUND

Primary schwannoma is a rare submucosal tumor of the esophagus, which is most often benign, and surgery is the only effective treatment. So far, only a few cases have been reported. Herein, we reported a single case diagnosed with primary esophageal schwannoma that was totally removed by submucosal tunneling endoscopic resection (STER).

CASE SUMMARY

A 62-year-old man presented to the hospital with a history of resection of a malignant gastric tumor and mild dysphagia. Endoscopic examination revealed a large submucosal elevated lesion in the esophagus 25-30 cm from the incisors. Endoscopic ultrasonography detected a 45 mm × 35 mm × 31 mm hypoechoic lesion; chest computed tomography showed a mass of approximately 55 mm × 35 mm × 29 mm. A preliminary examination showed features suggestive of a stromal tumor. Pathological findings indicated esophageal schwannoma. Next, STER alone was performed to completely resect the mass, and the patient recovered well post-surgery. Afterward, the patient was discharged and showed no tumor recurrence at 33 mo of follow-up.

CONCLUSION

Endoscopic resection is still an effective treatment for large esophageal schwannomas (> 30 mm) under meticulous morphological evaluation.

Submucosal Tunneling Techniques for Tumor Resection

The concept of third space endoscopy is based on the principle that the deeper layers of the gastrointestinal tract can be accessed by tunneling in the submucosal space and maintaining the integrity of the overlying mucosa. The mucosal flap safety valve enabled endoscopists to use submucosal space securely. The era of third space endoscopy started with peroral endoscopic myotomy for treatment of achalasia and has expanded to treat various other gastrointestinal disorders, such as mucosal lesions, submucosal tumors, extraluminal tumors, and refractory gastroparesis, Zenker diverticulum, and restoration of the completely obstructed esophageal lumen. Third space endoscopy rapidly emerged as a minimally invasive alternative to conventional surgery. Many studies discovered that this technique is safe and effective with excellent outcomes. Our review focused on the indications, techniques, clinical management, and adverse events of submucosal tunneling techniques for tumor resection.

Risk stratification in patients with upper gastrointestinal submucosal tumors undergoing submucosal tunnel endoscopic resection

Background

A substantial heterogeneity exists in patients with upper gastrointestinal submucosal tumors (SMTs). This study aimed to identify predictors of long procedure time (≥60 min), occurrence of procedure-related complications, and long hospital stay (≥6 days) in patients with SMTs undergoing submucosal tunnel endoscopic resection (STER) and stratify risk based on the predictors.

Methods

Sixty-six consecutive patients with upper gastrointestinal SMTs undergoing STER between January 2013 and December 2018 were retrospectively included. Binary logistic regression models were developed to identify predictors of outcomes. Receiver operating characteristic (ROC) curves were constructed to evaluate the discrimination of tumor size.

Results

Complete resection and en bloc resection of tumor were achieved in 66 (100%) and 64 patients (97%), respectively. Twenty-seven patients (41%) had a long procedure time, 10 (15%) developed STER-related complications, and 17 (26%) had a long hospital stay. On multivariable analysis, tumor size was an independent predictor of long procedure time (OR 1.37, 95% CI 1.13-1.67; p = 0.001), occurrence of complications (OR 1.06, 95% CI 1.01-1.10; p = 0.012), and long hospital stay (OR 1.05, 95% CI 1.01-1.09; p = 0.035). ROC curves identified a tumor of size 25 mm as the best cutoff; those who had a tumor above this value had a 76-fold risk of long procedure time, 8.56-fold risk of occurrence of complications, and 6.35-fold risk of long hospital stay.

Conclusion

Patients with a tumor size ≥25 mm had longer procedure time, higher risk of STER-related complications, and longer hospital stay; therefore, they should be classified as a high-risk group.

Endoscopic resection in the treatment of intramural esophageal bronchogenic cysts: A retrospective analysis of 17 cases

BACKGROUND

Intramural esophageal bronchogenic cysts (EBCs) are rare congenital malformations. Differences in reports on the clinical features of intramural EBCs and some controversies about the treatment strategy for intramural EBCs exist.

OBJECTIVES

To investigate the clinical characteristics of intramural EBCs and evaluate the safety and efficacy of endoscopic resection.

METHODS

The clinical and endoscopic features, endoscopic resection treatment, postoperative adverse events, and follow-up results of 17 patients with intramural EBCs were retrospectively studied.

RESULTS

Intramural EBCs exhibited male predominance with a male/female ratio of 58.8% (10/7) and were predominantly found in the distal esophagus. Approximately 94.1% of patients presented with gastrointestinal symptoms. All lesions were protruding masses covered by intact mucosal epithelium. The morphologies of intramural EBCs were diverse under white light endoscopy. On endoscopic ultrasonography, intramural EBCs presented as homogeneous or inhomogeneous hypoechoic or anechoic lesions. Eleven lesions originated from the muscularis propria, which underwent submucosal tunnel endoscopic resection (STER), and six lesions were from the submucosa, which underwent endoscopic submucosal dissection (ESD). Approximately 88.2% of patients underwent complete endoscopic resection. No serious pneumothorax, bleeding, pleural effusion, esophagotracheal fistula, or other adverse events occurred in all patients after endoscopic resection, and no cyst recurrence, metastasis, or esophageal scar stenosis was observed during the follow-up period.

CONCLUSIONS

Intramural EBCs can be treated by digestive endoscopic surgery. STER and ESD are safe, effective, and minimally invasive resection methods.

Landscape of esophageal submucosal tunneling endoscopic resection-related adverse events in a standardized lexicon: a large volume of 1701 cases

BACKGROUND

Submucosal tunneling endoscopic resection (STER) has been widely applied for esophageal submucosal tumors. This large volume study aims to provide a standard landscape of STER-related AEs for reference.

METHODS

1701 patients with esophageal SMTs undergoing STER were included at Zhongshan Hospital, Fudan University. Data of clinical characteristics and adverse events were collected and analyzed in depth. Adverse events were recorded by ASGE lexicon and graded by ASGE grading/Clavien-Dindo system. Risk factors for major AEs were analyzed by univariate and multivariate logistic regression.

RESULTS

Three hundred and twenty (18.8%) patients with 962 cases of adverse events were observed. Accordingly, 84 (5.0%) were classified as major AEs (moderate and severe) by ASGE grading and 37 (2.2%) were classified as major AEs (grades III-V) by Clavien-Dindo grading. First 1 year operation, distance > 6 cm from incision to tumor, piecemeal resection, partially extraluminal location, mucosal injury, and operation time > 60 min were included in the risk score model for major AEs of STER, with 57.1% sensitivity and 87.5% specificity.

CONCLUSIONS

STER was a safe procedure for diagnosis and treatment of esophageal SMTs with a total 18.8% incidence of AEs, among which only 5.0% were major AEs requiring therapeutic measurements.

Endoscopic resection of large subepithelial esophageal lesions via submucosal tunneling endoscopic resection and endoscopic submucosal dissection: a single-center, retrospective cohort study

BACKGROUND

This study aimed to compare the clinical outcomes between submucosal tunneling endoscopic resection (STER) and endoscopic submucosal dissection (ESD) for large subepithelial esophageal lesions (SELs) and analyze risk factors for perforation and piecemeal resection.

METHODS

The clinicopathological features and outcomes of endoscopic treatment of 56 patients with SELs with diameters ≥30 mm, diagnosed between June 2017 and December 2020, were reviewed in this retrospective cohort study. Patients were divided into two groups (ESD group and STER group).

RESULTS

The complete resection rates of the STER and ESD groups were 88.1% and 78.6%, respectively (p = .398). The operation time of STER was longer than ESD (p = .03), while the hospital stay of STER was shorter than ESD (p = .02). The rate of major adverse events associated with ESD was considerably higher than STER group (p = .035). The extraluminal growth pattern was a risk factor for piecemeal resection, and ESD was an independent risk factor for perforation. Regarding tumors with extraluminal growth patterns, the ESD group's perforation rate was significantly higher than the STER group (p = .009). There were no recurrence or metastases found during a mean follow-up of 24.4 months.

CONCLUSION

The STER technique has advantages of shorter hospital stays and fewer major adverse events than ESD. The extraluminal growth pattern seems to be a risk factor for piecemeal resection in both ESD and STER. STER appears to be a preferable choice for large SELs with extraluminal growth patterns.

[Submucosal tunneling endoscopic resection for large esophageal leiomyoma: technical aspects and risk of complications]

We analyzed the technical aspects and risk of possible complications after submucosal tunneling endoscopic resection for large esophageal leiomyoma. A patient with a 4-cm non-epithelial esophageal tumor underwent STER procedure in June 2018. Surgery time was 130 min. There were no intraoperative complications. Postoperative period was complicated with mediastinitis with reactive pneumonia and pleural effusion accompanied by episodes of hyperthermia up to 38°C for 5 days. The patient was discharged in 12 days after complete resolution of pneumonia confirmed by chest X-ray. Contrast-enhanced examination after 3 postoperative days revealed no contrast agent leakage outside the esophagus. The previously applied clips were visualized. Endoscopic examination in 3 months after surgery visualized postoperative scar without signs of deformation and narrowing of the esophagus. No complaints were observed throughout 3.5-year follow-up period.

CONCLUSION

This report demonstrates the advantages of tunnel dissection ensuring organ-sparing procedure with the best functional result. However, intra- and postoperative complications are possible after STER. The risk of complications and complexity of surgery depend on transverse size (>3.5 cm), shape and localization of tumor. Larger neoplasm is accompanied by more difficult surgery and higher risk of complications. Therefore, adequate selection of patients for STER is essential.

A Review of Endoscopic Full-thickness Resection, Submucosal Tunneling Endoscopic Resection, and Endoscopic Submucosal Dissection for Resection of Subepithelial Lesions

Gastrointestinal subepithelial tumors (SETs) are often found while performing routine endoscopy. Recently, there has been the development of new endoscopic techniques such as endoscopic submucosal dissection, submucosal tunnel endoscopic resection, and endoscopic full-thickness resection, all minimally invasive approaches which have made it possible to resect SETs that were previously resected with surgery. This review discusses the endoscopic treatment of patients with SETs, outcomes for endoscopic treatment, procedure-related complications, and advantages and disadvantages of these endoscopic techniques.

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.

Submucosal Tunneling Endoscopic Resection

Minimally invasive endoscopic resection procedures continue to evolve, with submucosal tunneling endoscopic resection (STER) being a durable option for en bloc resection of submucosal tumors. Whether STER can be effectively used for larger (>3.5 cm) lesions remains to be seen. STER-ET is a novel approach for removal of extraluminal tumors, but data are currently limited to support its use.

Endoscopic Esophageal Submucosal Tunnel Dissection for Cystic Lesions Originating from the Muscularis Propria of the Gastric Cardia

OBJECTIVE

To analyze the types and properties of cystic lesions originating from the muscularis propria of the gastric cardia (CLMPGC), explore the growth pattern and anatomical characteristics, and evaluate the safety, feasibility, and clinical efficacy of endoscopic esophageal submucosal tunnel dissection (ESTD).

METHODS

From September 2013 to July 2018, we treated 6 patients with CLMPGC whom we had diagnosed using endoscopy, endoscopic ultrasound (EUS), and Computed Tomography (CT) before the operations. ESTD was the best option for treatment for all these patients. Postoperative observation and follow-ups were performed, and the operational, clinical data, and treatment results are analyzed.

RESULTS

The mean age of the patients was 50.67 ± 11.59 years (male : female = 1 : 1). The only clinical manifestations the patients exhibited were upper abdominal discomfort. The diameter of the masses was 2.05 ± 0.73 (1.1-3.0) cm. The duration of the ESTD operation was 93.5 (82-256) mins, and the length of hospital stay was 7.50 ± 1.38 days. Postoperative pathology showed 4 cases of an epithelioid cyst, and 2 cases of mucocele with xanthogranuloma. There were no complications, such as hemorrhage, pneumothorax, and pleural effusion during and after the operation. No recurrence during the follow-ups was observed.

CONCLUSION

The CLMPGC were mainly mucocele and epidermoid cyst, in an expansive growth pattern, and these lesions had no distinct borders with the muscularis propria. The muscularis propria formed a complete wall of the lesion. There was no direct blood supply to the lesions from big blood vessels. Endoscopic esophageal submucosal tunnel dissection was a safe, feasible, and effective treatment for CLMPGC.

Clinical Efficacy of Single-Channel Gastroscopy, Double-Channel Gastroscopy, and Double Gastroscopy for Submucosal Tumors in the Cardia and Gastric Fundus

OBJECTIVE

To determine the feasibility and efficacy of single-channel gastroscopy, double-channel gastroscopy, and double gastroscopy in treating submucosal tumors in the cardia and gastric fundus.

METHODS

The data of 77 patients with submucosal tumors (SMTs) in the cardia and gastric fundus parts of the stomach who underwent single-channel gastroscopy, double-channel gastroscopy, and double gastroscopy were retrospectively analyzed. The observed therapeutic effect, complications, and local recurrence from these three groups were then compared.

RESULTS

All lesions were completely taken out under endoscopy, and the operation time for single-channel gastroscopy group was 20-90 min with an average of 44.5 min, and the postoperative hospitalization time was 5-9 days with an average of 7.5 days. The operation time for the double-channel gastroscopy group was 40-110 min with an average of 60.5 min, and the postoperative hospitalization time was 7-10 days with an average of 8.3 days, whereas the operation time of double gastroscopy group was 35-120 min with an average of 66.3 min, and the postoperative hospitalization time was 7-10 days with an average of 8.5 days. No patient was required to be transferred to the General Surgery Department for continuous treatment. Bleeding was noted from all the patients during operation, and hemostasis was performed successfully. Postoperative bleeding was not observed in any of the cases. Full-thickness resection was performed in all the three groups. No residual or recurrent lesions were detected via reexamination of gastroscopy in all the patients.

CONCLUSION

Single-channel gastroscopy, double-channel gastroscopy, and double gastroscopy present potential capability with distinctive advantages in the endoscopic treatment of submucosal tumors of the cardia and gastric fundus, and it also shows that appropriate operation methods should be selected based on the situation of an individual patient.

Suitability and efficacy of submucosal tunneling endoscopic resection for the treatment of giant leiomyoma in the middle and lower esophagus

Esophageal leiomyoma constitutes the majority of benign esophageal tumors, and detection rates are increasing. Submucosal tunneling endoscopic resection (STER) is a new technique developed to treat patients with esophageal leiomyoma, but the viability of STER for treating giant esophageal leiomyoma (GEL), particularly in the lower esophagus and close to the cardia, requires verification. This retrospective study assessed the efficacy of STER for the treatment of GEL. From January 2016 to April 2018, 10 patients underwent STER and endoscopic ultrasonography at the Endoscopic Center in Jianyang People's Hospital, and were found with histopathologically confirmed esophageal leiomyoma >3 cm. These cases were reviewed for successful excision, postoperative complications, and tumor recurrence. Seven of the 10 patients were men. Diagnoses of esophageal leiomyoma and negative resection margins were postoperatively confirmed in all 10 patients. All GELs were successfully excised. The mean operative time was 70.3 min (range, 28-100 min). The largest resected tumor was 14 cm. No adverse event occurred, and no delayed bleeding or associated infection. The patients were given postoperative conservative treatment and discharged. The mean hospitalization was 5.8 days (range, 3-10 d). During the scheduled follow-ups at 1, 3, 6, and 12 months post-STER, patients reported neither abdominal discomfort nor pain. No recurrent esophageal leiomyoma was detected at the follow-ups 3 months or longer following STER. STER is an effective and safe endoscopic resection technique for treating patients with GEL. Men may be at greater risk than women of developing GEL.

Comparison of different endoscopic resection techniques for submucosal tumors originating from muscularis propria at the esophagogastric junction

Background

To compare the outcomes of submucosal tunneling endoscopic resection (STER) and submucosal excavation (ESE) for the treatment of submucosal tumors (SMTs) arising from the muscularis propria (MP) at the esophagogastric junction (EGJ).

Methods

A retrospective analysis of patients with SMTs at EGJ who underwent STER and ESE from October 2011 to October 2017 was performed. The outcomes evaluated were operation time, complete resection rate, adverse events, and tumor recurrence.

Results

Ninety patients were included in this study. Complete resection rates in the STER group were higher than those of the ESE group (100 vs. 92%, p < 0.05). For tumors ≤15 mm, both techniques achieved 100% complete resection rate; but for tumors > 15 mm, complete resection rate was higher in the STER group than the ESE group (100% vs. 77.8%, p < 0.05). Subgroup analyses revealed that the operation time of STER for in cardiac-gastric group was longer than that for ESE (145.14 ± 42.43 min vs. 70.32 ± 39.84 min, p <  0.05). The air leakage symptoms were more frequent in STER group (90.9% vs. 50.0%, p < 0.05). No tumor recurrence occurred in both the STER and ESE groups.

Conclusions

For SMTs ≤15 mm, both STER and ESE have similar satisfactory therapeutic outcomes. However, in the cardiac-gastric subgroup, STER had a longer operative time compared to the ESE procedure. For SMTs > 15 mm, STER is the preferred choice due to its higher complete resection rate.

Submucosal tunneling endoscopic resection for an unusually sized esophageal submucosal tumor protruding into the mediastinum

A 50-year-old female came to our hospital with a 6-month history of upper abdominal discomfort. An upper endoscopy detected a protruding lesion that measured 3.0×2.0 cm at around 35-38 cm from the incisors located on the posterior wall. Endoscopic ultrasonography revealed a homogeneous hyperechoic mass located in the muscularis propria, with no malignant features. Contrast-enhanced CT was also performed. A submucosal tunneling endoscopic resection (STER) was performed. A longitudinal mucosal incision was made and a submucosal tunnel created, which uncovered an irregularly giant tumor. The size of the resected tumor was 3.0×4.0×1.5cm and the histopathological analysis identified leiomyomas. The patient was discharged 7 days after the procedure and 3 months after the surgery there was no recurrence on the CT scan. Meanwhile, the discomfort of the patient was relieved after STER and there were no severe complications during the 6-month follow-up. DISCUSSION Esophageal leiomyoma is a benign submucosal tumor derived from the muscularis propria layer of the esophagus [1]. STER has been demonstrated to be safe and effective for treating small (≤3.5 cm) and solitary esophageal leiomyoma with low complication rates [2-3]. Most esophageal leiomyoma grow into the lumen and their positions in the tunnel are relatively superficial and the entire surgery is comparatively safe. In this case, the tumor was very large and was close to the mediastinum, which greatly increases the difficulty of surgery. However, STER is recommended according to our experience, even in rare cases.

Comparison Between Submucosal Tunneling Endoscopic Resection (STER) and Other Resection Modules for Esophageal Muscularis Propria Tumors: A Retrospective Study

Background

Surgery has been considered to be the primary approach for resection of esophageal muscularis propria tumors. With the development of endoscopic technology, new techniques such as endoscopic submucosal dissection (ESD) and submucosal tunneling endoscopic resection (STER) have emerged for resecting these lesions. Previous studies have demonstrated that STER might be an intriguing alternative. This study aimed to evaluate the clinical value of STER by comparing it to other resecting modules.

Material/Methods

Clinical outcome and data were retrospectively collected from patients with esophageal muscularis propria tumors who underwent resection either endoscopically or thoracoscopically. The clinical data were statistically analyzed.

Results

A total of 137 patients were enrolled. They were divided into 3 groups: a STER group (27 patients), an ESD group (42 patients), and a thoracoscopic enucleation (TE) group (68 patients). There were no significant differences among the 3 groups in gender, age, pathological type of tumors, or major adverse events (P>0.05). However, the STER group had the shortest duration of hospitalization and the lowest cost (P<0.05). Furthermore, the STER group was superior in operation time and the location of tumors to the TE group. Moreover, STER outperformed ESD in the resection of large tumors (P<0.05). Although STER had the lowest en bloc resection rate, no recurrence or metastasis was noted during a mean follow-up of 22.14 months (range 3 to 60 months).

Conclusions

STER is a feasible, safe, and effective approach for the resection of esophageal muscularis propria tumors ≤40 mm. We recommend STER as a potent alternative for these tumors.

Endoscopic full thickness resection versus submucosal tunneling endoscopic resection for removal of submucosal tumors: a review article

Submucosal tumors (SMT) are protuberant lesions with intact mucosa that have a wide differential. These lesions may be removed by standard polypectomy, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), or surgically. However, in lesions that arise from the muscularis propria, full thickness resection is recommended. This can be completed using either endoscopic full thickness resection (EFTR) or submucosal tunneling endoscopic resection (STER). EFTR can be accomplished by completing a full thickness resection followed by defect closure or by securing gastrointestinal wall patency before resection. STER is an option that first creates a mucosal dissection proximal to the lesion to allow a submucosal tunnel to be created. Using this tunnel, the lesion may be resected. When comparing STER to EFTR, there was no significant difference when evaluating tumor size, operation time, rate of complications, or en bloc resection rate. However, suture time, amount of clips used, and overall hospital stay were decreased in STER. With these differences, EFTR may be more efficacious in certain parts of the gastrointestinal tract where a submucosal tunnel is harder to accomplish.

Endoscopic resection for subepithelial lesions-pure endoscopic full-thickness resection and submucosal tunneling endoscopic resection

Endoscopic full-thickness resection (EFTR) and submucosal tunneling endoscopic resection (STER) are the frontier of therapeutic endoscopic. These two methods rely on the skillset and equipment of endoscopic submucosal dissection (ESD) while going beyond the boundaries of the gastrointestinal lumen. They are both representatives of natural orifice transluminal endoscopic surgery, with STER being a direct off-shoot of peroral endoscopic myotomy (POEM). Both techniques are designed for the removal of gastrointestinal tumors originating from the muscularis propria but tend to be used in different organs and come with respective challenges. In this review we will go over the history, indication, technique and literature of these two techniques.

Current Status of Endoscopic Resection of Gastric Subepithelial Tumors

Most gastrointestinal (GI) subepithelial tumors (SETs) are identified incidentally during endoscopic examination and are located in the stomach. Some SETs are malignant or have the potential to become malignant. Tumors originating from deeper layers, such as the muscularis propria or serosa, are not easy to diagnose and resect. Current guidelines recommend yearly endoscopic surveillance of SETs smaller than 2 cm. This recommendation may not be cost-effective in managing GI SETs. Endoscopic resection results not only in obtaining sufficient tissue for pathological diagnosis but also in resection and curing the tumor. Many different endoscopic methods for resection of GI SETs have been published in the literature. To avoid confusion, we have divided these methods into standard endoscopic submucosal dissection, modified endoscopic submucosal dissection, submucosal tunneling endoscopic resection, and nonexposed and exposed endoscopic full-thickness resection. These procedures offer less invasive approaches than surgery for resection of GI SETs and may be the most cost-effective in taking care of patients with GI SETs.

Mucosal loss as a critical factor in esophageal stricture formation after mucosal resection: a pilot experiment in a porcine model

BACKGROUND AND AIM

Esophageal stricture is a major complication of large areas endoscopic submucosal dissection (ESD). Until now, the critical mechanism of esophageal stricture remains unclear. We examined the role of mucosal loss versus submucosal damage in esophageal stricture formation after mucosal resection using a porcine model.

MATERIALS AND METHODS

Twelve swine were randomly divided into two groups, each of 6. In each group, two 5-cm-long submucosal tunnels were made to involve 1/3rd of the widths of the anterior and posterior esophageal circumference. The entire mucosal roofs of both tunnels were resected in group A. In group B, the tunnel roof mucosa was incised longitudinally along the length of the tunnel, but without excision of any mucosa. Stricture formation was evaluated by endoscopy after 1, 2, and 4 weeks, respectively. Anatomical and histological examinations were performed after euthanasia.

RESULTS

Healing observed on endoscopy in both groups after 1 week. Group A (mucosa resected) developed mild-to-severe esophageal stricture, dysphagia, and weight loss. In contrast, no esophageal stricture was evident in group B (mucosa incisions without resection) after 2 and 4 weeks, respectively. Macroscopic examination showed severe esophageal stricture and shortening of esophagus in only group A. Inflammation and fibrous hyperplasia of the submucosal layer was observed on histological examination in both groups.

CONCLUSION

The extent of loss of esophageal mucosa appears to be a critical factor for esophageal stricture. Inflammation followed by fibrosis may contribute to alteration in compliance of the esophagus but is not the main mechanism of postresection stricture.

Consensus on the digestive endoscopic tunnel technique

With the digestive endoscopic tunnel technique (DETT), many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and muscularis propria (MP). Through the tunnel, endoscopic diagnosis or treatment is performed for lesions in the mucosa, in the MP, and even outside the gastrointestinal (GI) tract. At present, the tunnel technique application range covers the following: (1) Treatment of lesions originating from the mucosal layer, e.g., endoscopic submucosal tunnel dissection for oesophageal large or circular early-stage cancer or precancerosis; (2) treatment of lesions from the MP layer, per-oral endoscopic myotomy, submucosal tunnelling endoscopic resection, etc.; and (3) diagnosis and treatment of lesions outside the GI tract, such as resection of lymph nodes and benign tumour excision in the mediastinum or abdominal cavity. With the increasing number of DETTs performed worldwide, endoscopic tunnel therapeutics, which is based on DETT, has been gradually developed and optimized. However, there is not yet an expert consensus on DETT to regulate its indications, contraindications, surgical procedure, and postoperative treatment. The International DETT Alliance signed up this consensus to standardize the procedures of DETT. In this consensus, we describe the definition, mechanism, and significance of DETT, prevention of infection and concepts of DETT-associated complications, methods to establish a submucosal tunnel, and application of DETT for lesions in the mucosa, in the MP and outside the GI tract (indications and contraindications, procedures, pre- and postoperative treatments, effectiveness, complications and treatments, and a comparison between DETT and other operations).

Submucosal tunneling endoscopic resection: An effective and safe therapy for upper gastrointestinal submucosal tumors originating from the muscularis propria layer

AIM

To evaluate the effectiveness and safety of submucosal tunneling endoscopic resection (STER) and compare its outcomes in esophageal and cardial submucosal tumors (SMTs) of the muscularis propria (MP) layer.

METHODS

From May 2012 to November 2017, 173 consecutive patients with upper gastrointestinal (GI) SMTs of the MP layer underwent STER. Overall, 165 patients were included, and 8 were excluded. The baseline characteristics of the patients and SMTs were recorded. The en bloc resection rate, complete resection rate, residual rate, and recurrence rate were calculated to evaluate the effectiveness of STER, and the complication rate was recorded to evaluate its safety. Effectiveness and safety outcomes were compared between esophageal and cardial SMTs.

RESULTS

One hundred and twelve men and 53 women with a mean age of 46.9 ± 10.8 years were included. The mean tumor size was 22.6 ± 13.6 mm. Eleven SMTs were located in the upper esophagus (6.7%), 49 in the middle esophagus (29.7%), 46 in the lower esophagus (27.9%), and 59 in the cardia (35.7%). Irregular lesions accounted for 48.5% of all lesions. STER achieved an en bloc resection rate of 78.7% (128/165) for GI SMTs with an overall complication rate of 21.2% (35/165). All complications resolved without intervention or were treated conservatively without the need for surgery. The en bloc resection rates of esophageal and cardial SMTs were 81.1% (86/106) and 72.1% (42/59), respectively (P = 0.142), and the complication rates were 19.8% (21/106) and 23.7% (14/59), respectively, (P = 0.555). The most common complications for esophageal SMTs were gas-related complications and fever, while mucosal injury was the most common for cardial SMTs.

CONCLUSION

STER is an effective and safe therapy for GI SMTs of the MP layer. Its effectiveness and safety are comparable between SMTs of the esophagus and cardia.

Endoscopic Full Thickness Resection

Recent advances in minimally invasive endoscopic approaches have pushed the boundaries of well-established resection techniques for therapeutic and diagnostic applications. Endoscopic full thickness resection techniques are a key development in the management of challenging epithelial and subepithelial lesions that are not amenable to conventional endoscopic resection methods and previously required a surgical approach. Endoscopic full thickness biopsy represents a paradigm shift in tissue acquisition and will enhance our understanding of the pathophysiology, and guide therapy, of gastrointestinal neuromuscular diseases, as well as other inflammatory and neoplastic conditions. This review highlights current tools and techniques available for endoscopic full thickness resection and biopsy, as well as outcomes from such interventions.

Minimally Invasive, Organ-preserving Surgery for Large Submucosal Tumors in the Abdominal Esophagus

BACKGROUND

Surgical resection of submucosal tumors (SMTs) in the abdominal esophagus is not standardized. Enucleation may be a minimally invasive option, whereas its oncological validity is not very clear. Moreover, how to treat the esophageal wall defect after enucleation and necessity of additional antireflux procedure are also undetermined.

METHODS

In 13 patients with a SMT originating the abdominal esophagus laparoscopic enucleation was performed with preserving the integrity of submucosa. When the muscular layer defect was <4 cm it was directly closed by suturing, whereas it was left open in case the defect was larger. Fundoplication was added when the esophagus was dissected posteriorly or the myotomy was not closed.

RESULTS

Tumors were resected en-bloc without rupture in all cases. In 5 patients myotomy was closed, whereas in the remaining 8 it was left open. In 11 patients fundoplication was added (Toupet in 5 and Dor in 6). The patients developed neither regurgitation nor stenosis postoperatively. The histopathologic findings revealed leiomyoma in 9 patients, whereas the other 4 were miscellaneous. The average tumor size was 5.5 cm (range, 2.8 to 8.8). Microscopically surgical margin was negative in all cases.

CONCLUSIONS

Laparoscopic enucleation of SMTs in the abdominal esophagus seems to be safe, reproducible operation enabling preservation of function of the lower esophagus and esophagogastric junction. Even when the muscular defect is not approximated additional fundoplication can minimize the risk of postoperative reflux disease.

A promising Forcep Strip Method for gastrointestinal subepithelial tumors originating from the muscularis propria

BACKGROUND

Subepithelial tumors (SETs) originating from the muscularis propria layer are unlikely to be resected completely and safely. We developed the Forcep Strip Method (FSM) for the resection of SETs in the stomach.

AIMS

This study aimed to evaluate the feasibility and safety of the FSM.

METHODS

Endoscopic SET resection using electrical forceps was performed in 11 consecutive patients with clinical indications for lesion removal. Following injection around the tumor, the adjacent mucosa or submucosa was grasped with the hot forceps and pulled away to form a "tent". The tumor was dissected from the muscularis propria layer and carefully removed using coagulating forceps.

RESULTS

The FSM was successful in 10 of the 11 patients in the series; one patient required surgery due to respiratory depression during the procedure. The complete resection rate was 100% and no major complications including bleeding and perforation occurred. Mean procedure time was 39.3 ± 14.7 min, mean hospitalization time was 5.0 ± 1.2 days, and mean tumor size was 17.1 ± 4.7 mm.

CONCLUSION

FSM was found to be an easy, safe, and effective procedure for the treatment of gastric SETs originating from the muscularis propria layer.

Expanding Role of Third Space Endoscopy in the Management of Esophageal Diseases

OPINION STATEMENT: "Third space" endoscopy, also commonly referred as submucosal endoscopy, is founded on the principle that the deeper layers of the gastrointestinal (GI) tract can be accessed by tunneling in the submucosal space without compromising the integrity of the overlying mucosa. Peroral endoscopic myotomy (POEM), endoscopic submucosal dissection (ESD), and submucosal tunneling endoscopic resection (STER) are innovative techniques within the field of third space endoscopy in the management of esophageal disorders. POEM has become an accepted minimally invasive therapy for achalasia and related motility disorders with excellent short-term results, with early studies yielding similar efficacy to surgical myotomy and increased durability when compared to pneumatic balloon dilation (PBD). Data are needed to establish long-term outcomes with POEM, with particular interest on the incidence of gastroesophageal reflux, which appears to be higher than initially anticipated. ESD, a mature endoscopic resection technique in Asia, has recently gained traction in the West as a viable option for the management of early Barrett's esophagus (BE) neoplasia. Compared to standard endoscopic mucosal resection (EMR), ESD allows the en bloc resection of lesions irrespective of size, which may facilitate histological interpretation and reduce recurrence rates. Large prospective randomized controlled trials are needed to validate the efficacy and safety of this technique and to further define its role in the endoscopic armamentarium in early BE neoplasia. STER is an attractive technique that theoretically permits the resection of subepithelial esophageal tumors (SETs) arising from the deeper GI layers. Initial studies from highly experienced endoscopic centers support its technical feasibility and safety, although these results should be interpreted with caution due to variability arising from small numbers and heterogeneity among studies. Overall, third space endoscopy is an expanding field within endoscopic therapeutics for the treatment of esophageal diseases. While initial results have been very promising, large prospective studies, long-term data, and structured training programs with the establishment of competency parameters are needed before third space endoscopy can be advocated outside of highly specialized centers.

Endoscopic Treatment of Subepithelial Tumors

Gastrointestinal subepithelial tumors (SETs) are generally found during endoscopy and their incidence has gradually increased. Although the indications for the endoscopic treatment of patients with SETs remain to be established, the feasibility and safety of endoscopic dissection, including the advantages of this method compared with surgical treatment, have been validated in many studies. The development of endoscopic techniques, such as endoscopic submucosal dissection, endoscopic enucleation, endoscopic excavation, endoscopic submucosal tunnel dissection, submucosal tunnel endoscopic resection, and endoscopic full-thickness resection has enabled the removal of SETs while reducing the occurrence of complications. Here, we discuss the endoscopic treatment of patients with SETs, outcomes for endoscopic treatment, and procedure-related complications. We also consider the advantages and disadvantages of the various endoscopic techniques.

Safety and efficacy of endoscopic submucosal dissection of large (≥3 cm) subepithelial tumors located in the cardia

BACKGROUND

Upper gastrointestinal subepithelial tumors (SETs) may harbor potential malignancy. Although it is well recognized that large SETs should be resected, the treatment strategy remains controversial. Compared to surgical resection, endoscopic resection has many advantages such as less invasive, shorter hospital stay, lower costs, and better quality of life. However, Endoscopic resection of large SETs in the cardia is challenging. The purpose of this study was to evaluate the safety and efficacy of endoscopic submucosal dissection (ESD) in the treatment of such SETs.

METHODS

A total of 41 patients with large SETs (≥3 cm in diameter) located in the cardia were involved in the study. All patients underwent ESD. Data on therapeutic outcomes and follow-up were collected, for analysis of risk factors of complication rates.

RESULTS

The average tumor size was 4.7 ± 1.7 cm. The average procedure time was 69.3 ± 32.7 min and the average postoperative hospital stay was 3.5 ± 1.1 days. A total of 41 tumors were removed successfully, in which 35 were leiomyomas, three were gastrointestinal stromal tumors, two were lipomas, and one was gastritis cystica profunda. The en bloc resection rate was 90.2%, and was significantly higher for tumors with a round or oval shape (100%) than for those with an irregular shape (75.0%) (P < 0.05). Five patients experienced complications (12.2%), all of which were managed conservatively. The complication rates were significantly higher in patients with a tumor originating from the deep muscularis propria layer and demonstrating a trans-cardia growth pattern. No residual or tumor recurrence was observed and no stricture occurred during the follow-up period (average, 26.7 ± 18.4 months).

CONCLUSIONS

ESD is safe and effective to curatively remove most large SETs in the cardia, and may serve as an accurate histopathology measurement to direct future therapy.

Submucosal Tunneling Endoscopic Resection for the Treatment of Gastrointestinal Submucosal Tumors Originating from the Muscularis Propria Layer

Surgical resection and endoscopic resection comprise two alternative options for the treatment of submucosal tumors (SMTs) originating from the muscularis propria (MP) layer. Endoscopic resection is minimally invasive compared with surgical resection. Conventional non-tunneling techniques, such as endoscopic submucosal dissection (ESD), endoscopic submucosal excavation (ESE), and endoscopic full-thickness resection (EFR) have been demonstrated to be safe and effective. However, these techniques fail to maintain the integrity of the mucosa and induce high risk of perforation, infection, and postoperative strictures. Submucosal tunneling endoscopic resection (STER) is a novel surgical technique that can maintain the integrity of the mucosa by establishing a tunnel between the submucosal and the MP layers. STER has been proven to be effective and safe for the treatment of SMTs. Currently, STER has become a standard treatment for gastrointestinal (GI) SMTs originating from the MP layer, notably in China. In the present review, we describe the indications, procedures, postoperative care, efficacy and safety outcomes, and future perspectives of STER for GI SMTs originating from the MP layer.

Current status of submucosal tunneling endoscopic resection for gastrointestinal submucosal tumors originating from the muscularis propria layer

Gastrointestinal submucosal tumors (SMTs) have been increasingly identified via the use of endoscopic ultrasonography, and removal is often recommended for SMTs that are >2 cm in diameter or symptomatic. Submucosal tunneling endoscopic resection (STER), also known as submucosal endoscopic tumor resection, endoscopic submucosal tunnel dissection or tunneling endoscopic muscularis dissection, is a novel endoscopic technique for treating gastrointestinal SMTs originating from the muscularis propria layer, and has been demonstrated to be effective in the removal of SMTs with a decreased rate of recurrence by clinical studies. STER may be performed for patients with esophageal or cardia SMTs, and its application has expanded beyond these types of SMTs due to modifications to the technique. The present study reviewed the applications, procedure, efficacy and complications associated with STER.

Endoscopic Submucosal Tunnel Dissection for Upper Gastrointestinal Submucosal Tumors Originating from the Muscularis Propria Layer: A Single-Center Study

BACKGROUND/AIMS

In recent years, endoscopic submucosal tunnel dissection (ESTD) has gained popularity worldwide. The aim of this study was to evaluate the safety and efficacy of ESTD in treating upper gastrointestinal submucosal tumors (SMTs) in a large-volume endoscopic center.

METHODS

Patients with SMTs were enrolled in this study between January 2012 and January 2015. Demographic data, clinical data, and treatment outcome were collected and analyzed.

RESULTS

Seventy SMTs originating from the muscularis propria (MP) layer were identified in 69 patients. All patients successfully underwent the ESTD procedure. The mean procedure time was 49.0±29.5 minutes, and the mean tumor size was 18.7±7.2 mm. Among all lesions, the majority (70.0%) were located in the esophagus, 12.9% in the cardia, and 17.1% in the stomach. Complete resection was achieved in 67 lesions (95.7%). Perforation occurred in three patients (4.3%), who were treated by endoclips. Pneumothorax occurred in two patients (2.9%) and was successfully managed by thoracic drainage. During a median follow-up of 18.1 months, patients were free of local recurrence or distant metastasis.

CONCLUSIONS

Our results demonstrated the feasibility and safety of ESTD in treating upper gastrointestinal SMTs originating from the MP layer. Large-scale comparative studies with other treatment methods should be conducted in the future.

Comparison of endoscopic submucosal tunneling dissection and thoracoscopic enucleation for the treatment of esophageal submucosal tumors

BACKGROUND AND AIMS

Endoscopic submucosal tunneling dissection (ESTD) has been proved to be safe and effective for removal of esophageal submucosal tumors (SMTs) and can maintain the mucosal integrity compared with other endoscopic methods. The aim of the study was to estimate the safety and efficacy of ESTD as well as compare its efficacy with thoracoscopic enucleation for esophageal SMTs, which is used increasingly as a minimally invasive approach.

METHODS

We retrospectively collected the clinical data of patients with esophageal SMTs <40 mm who underwent ESTD or thoracoscopic enucleation at Nanfang Hospital between January 2008 and August 2016. Epidemiologic data (sex, age), tumor location, tumor size, en bloc resection rate, adverse events, pathologic results, length of postoperative hospital stay, and cost were compared between ESTD and thoracoscopic enucleation.

RESULTS

A total of 126 patients were included. A total of 74 patients underwent ESTD, and the other 52 underwent thoracoscopic enucleation. There was no significant difference between the 2 groups in sex, age, tumor size, hospitalization expense, infection, adverse events, and en bloc resection rate (P < .05). However, patients in the ESTD group had a shorter operating time, less estimated blood loss, shorter length of postoperative hospital stay, and lower chest pain level (P < .05). Kaplan-Meier curves for disease-free survival also showed no statistically significant difference between ESTD and thoracoscopic enucleation groups during the median follow-up of 19.5 and 42 months, respectively.

CONCLUSIONS

The treatment efficacy was comparable between the ESTD and thoracoscopic enucleation for esophageal SMTs <40 mm. However, there was a significant advantage in the ESTD group for a shorter operating time, reduced postoperative chest pain, and shorter hospitalization.

Effectiveness and safety of endoscopic resection for gastric GISTs: a systematic review

AIMS

To evaluate the effectiveness and safety of endoscopic resection for gastric gastrointestinal stromal tumors (GISTs).

MATERIAL AND METHODS

The effectiveness and safety of endoscopic resection were mainly assessed by complete resection rate, postoperative adverse event rate, and recurrence rate. Moreover, a comparison of endoscopic with laparoscopic resection for gastric GISTs was made through weighted mean difference by STATA 12.0 with regard to operation time, blood loss, and length of stay after including patients who underwent endoscopic or laparoscopic resection for gastric GISTs in the comparative studies.

RESULTS

Eleven studies investigating endoscopic resection for GISTs were included. For stromal tumors <2 cm in average diameters the pooled rates of complete resection, postoperative adverse events and recurrence were 0.97, 0.08, and 0.03, respectively. Only five retrospective studies directly compared endoscopic with laparoscopic resection for gastric GISTs with average diameters from 1.1 cm to 3.8 cm, and endoscopic resection had a shorter operation time than laparoscopic resection, but there were no significant differences in intraoperative blood loss, length of stay, postoperative complications, and postoperative recurrence rates between the two approaches.

CONCLUSIONS

Endoscopic resection is predominantly tried for gastric GISTs of relatively small size. It seems effective and safe for gastric GISTs <2 cm in average diameter, with relatively short operation times.

Gastric Schwannoma: A Tumor Must Be Included in Differential Diagnoses of Gastric Submucosal Tumors

Gastric schwannoma (GS) is a rare neoplasm of the stomach. It accounts for 0.2% of all gastric tumors and is mostly benign, slow-growing, and asymptomatic. Due to its rarity, GS is not widely recognized by clinicians, and the precise differential diagnosis between GS and other gastric submucosal tumors remains difficult preoperatively. The present study reports a case of GS misdiagnosed as gastrointestinal stromal tumor and reviews the clinical, imaging, and pathological features, treatment, and follow-up of 221 patients with GS previously reported in the English literature. Although GS is rare, the case reported in the current study highlights the importance of including GS in differential diagnoses of gastric submucosal tumors. Furthermore, the findings of the review suggest that although many cases are asymptomatic, the most common symptoms are abdominal pain or discomfort, not gastrointestinal bleeding, and malignant GSs present with clinical symptoms more commonly. Although large-sample multicenter studies on the efficacy, safety, and oncological outcomes of minimally invasive techniques are required, the findings presented herein may be helpful for clinicians when diagnosing or treating GS.

Endoscopic submucosal dissection for gastric gastrointestinal stromal tumors: a retrospective cohort study

BACKGROUND AND AIM

Endoscopic submucosal dissection (ESD) has been used to remove submucosal tumors. However, with regard to the potential malignant behavior of gastrointestinal stromal tumors (GISTs), whether ESD can be recommended for treatment is still controversial. Therefore, we evaluated the efficacy and safety of ESD for removal of GISTs in the muscularis propria (MP) layer and to assess the possible risk factors for a gastric-wall defect (GWD).

METHODS

For 168 GISTs located in the MP layer from 168 consecutive patients, the baseline information, complications, and therapeutic outcomes were recorded. Subsequently, risk factors for a GWD were analyzed.

RESULTS

Most GISTs (106/168) were located in the fundus of the stomach. Tumor shapes in 154 patients (91.7%) were regular, and the median size of the tumor was 1.5 (range 0.5-6.0) cm. The en bloc resection rate was 100% and the median procedure time was 46.5 (33-181) min. A GWD was observed in 71 patients (42.3%) and delayed bleeding occurred in 2 patients (1.2%), and they were treated by clips. A total of 117 patients with a GIST were at very low risk, 37 patients were at low risk, and 14 patients were at mild risk. No local recurrences or distant metastases were observed during a median follow-up of 25 (6-67) months. Univariate and multivariate logistic regression analyses identified the tumor type to be an independent risk factor for a GWD during ESD (odds ratio 29.82, 95% confidence interval 10.87-81.80, P < 0.001).

CONCLUSION

ESD is a safe and feasible method for gastric GISTs, especially for tumor types A and B. Endoscopic ultrasound can aid evaluation of the tumor type before ESD, which is an independent risk factor correlated with a GWD upon ESD.

Submucosal tunneling endoscopic resection using methylene-blue guidance for cardial subepithelial tumors originating from the muscularis propria layer

Submucosal tunneling endoscopic resection (STER) of subepithelial tumors (SETs) originating from the muscularis propria (MP) layer in the cardia is rarely performed due to the difficulty of creating a submucosal tunnel for resection. The aim of this study is to evaluate the feasibility of STER using methylene-blue guidance for SETs originating from the MP layer in the cardia. From January 2012 to December 2014, 56 patients with SETs originating from the MP layer in the cardia were treated with STER using methylene-blue guidance. The complete resection rate and adverse event rate were the main outcome measurements. Successful complete resection by STER was achieved in all 56 cases (100%). The median size of the tumor was 1.8 cm. Nine patients (15.3%) had adverse events including subcutaneous emphysema, pneumoperitoneum, pneumothorax, and pleural effusion. These nine patients recovered successfully after conservative treatment without endoscopic or surgical intervention. No residual or recurrent tumors were detected in any patient during the follow-up period (median, 25 months). The adverse event rate was significantly higher for tumors originating in the deeper MP layers (46.7%) than in the superficial MP layers (4.9%) (P < 0.05), differed significantly according to tumor size (5.4% for tumors < 2.0 cm vs. 36.8% for tumors ≥ 2.0 cm; P < 0.05), and also differed significantly in relation to the tumor growth pattern (4.1% for the intraluminal growth vs. 100% for the extraluminal growth; P < 0.001). STER using methylene-blue guidance appears to be a feasible method for removing SETs originating from the MP layer in the cardia.

Endoscopic submucosal tunnel dissection of upper gastrointestinal submucosal tumors: A comparative study of hook knife vs hybrid knife

AIM

To compare the efficacy and safety of a hook knife (HO) with a hybrid knife (HK) during endoscopic submucosal tunnel dissection (ESTD) procedure.

METHODS

Between August 2012 and December 2015, the ESTD procedure was performed for 83 upper GI submucosal lesions, which originated from the muscularis propria layer identified by upper endoscopy and endoscopic ultrasonography. Of these, 34 lesions were treated by a HO, whereas 49 lesions were treated by a HK. Data regarding age, gender, presenting symptoms, tumor location and size, procedure time, complications, en bloc resection rate and others were analyzed and compared between the two groups.

RESULTS

There were no significant differences in the age, gender, presenting symptoms and tumor location between the two groups. ESTD was successfully completed in all the patients, and no case was converted to laparoscopy. The mean procedure time was significantly shorter in the HK group than in the HO group (41.3 ± 20.3 min vs 57.2 ± 28.0 min, P = 0.004). The mean frequency of device exchange was 1.4 ± 0.6 in the HK group and significantly less than 3.3 ± 0.6 in the HO group (P < 0.001). The differences in tumor size and histopathological diagnoses were not significant between the two groups (P = 0.813, P = 0.363, respectively). Both groups had an equal en bloc resection rate and complete resection rate. Additionally, the complication rate was similar between the two groups (P = 0.901). During the follow-up, no recurrence occurred in either group.

CONCLUSION

We demonstrate for the first time that HO and HK do not differ in efficacy or safety, but HK reduces the frequency of device exchange and procedure time.

Submucosal tunneling endoscopic resection of upper gastrointestinal tract tumors arising from muscularis propria

The management of incidentally discovered small upper gastrointestinal (GI) tract submucosal tumors (SMT) remains debatable. In this review, we summarize the evolving experience with submucosal tunneling endoscopic resection (STER) of upper GI SMTs originating from the muscularis propria. From 16 original studies, we reviewed a total of 703 patients with 736 lesions. Of these, 436 were located in the esophagus, 146 in the esophagogastric junction (EGJ) and 154 in the stomach. The composite complete resection rate (CRR) for STER of upper GI tumors arising from the muscularis propria layer was 99.8% (445/446). The composite CRR for STER of esophageal, EGJ and gastric SMTs arising from the muscularis propria layer was 100% (208/208),100% (78/78)and 100% (115/115), respectively. The composite en bloc resection rate (EBRR) for STER of upper GI tumors arising from the muscularis propria layer was 94.6% (679/718). The composite EBRR for STER of esophageal, EGJ and gastric SMTs arising from the muscularis propria layer was 98.6% (205/208), 96.2% (75/78) and 97.9% (95/97), respectively. Tumor recurrence rate was 0%. The reported complication rate for STER was high but the majority responded to conservative management. STER is a minimally invasive and efficacious alternative to surgery, especially for patients with small tumors (<3 cm). Careful selection of candidates remains crucial for excluding potentially malignant tumors.

Submucosal tunneling endoscopic resection using methylene-blue guidance for cardial subepithelial tumors originating from the muscularis propria layer

Submucosal tunneling endoscopic resection (STER) of subepithelial tumors (SETs) originating from the muscularis propria (MP) layer in the cardia is rarely performed due to the difficulty of creating a submucosal tunnel for resection. The aim of this study was to evaluate the feasibility of STER using methylene-blue guidance for SETs originating from the MP layer in the cardia. From January 2012 to December 2014, 56 patients with SETs originating from the MP layer in the cardia were treated with STER using methylene-blue guidance. The complete resection rate and adverse event rate were the main outcome measurements. Successful complete resection by STER was achieved in all 56 cases (100%). The median size of the tumor was 1.8 cm. Nine patients (15.3%) had adverse events including subcutaneous emphysema, pneumoperitoneum, pneumothorax, and pleural effusion. These nine patients recovered successfully after conservative treatment without endoscopic or surgical intervention. No residual or recurrent tumors were detected in any patient during the follow-up period (median, 25 months). The adverse event rate was significantly higher for tumors originating in the deeper MP layers (46.7%) than in the superficial MP layers (4.9%) (P < 0.05), differed significantly according to tumor size (5.4% for tumors < 2.0 cm vs. 36.8% for tumors ≥ 2.0 cm; P < 0.05), and also differed significantly in relation to the tumor growth pattern (4.1% for the intraluminal growth vs. 100% for the extraluminal growth; P < 0.001). STER using methylene-blue guidance appears to be a feasible method for removing SETs originating from the MP layer in the cardia.

Esophageal insufflation computed tomography for the diagnosis and management of esophageal submucosal tumors

BACKGROUND

The selection of therapy for benign esophageal lesions depends in part on whether the lesion extends to or through the esophageal muscle wall. The advent of endoscopic dissection of deep lesions has made this distinction important in the choice between different forms of advanced endoscopic therapy. The goal of this study was to evaluate esophageal insufflation computed tomography (EICT) for the diagnosis and management of esophageal submucosal tumors (SMTs).

METHODS

Between April 2011 and May 2013 at the Second Affiliated Hospital of Harbin Medical University, 27 patients with esophageal SMTs diagnosed by gastroscopy were studied observationally. Entry criteria included tumors larger than 0.5 cm. We compared endoscopic ultrasound (EUS) and EICT to assess lesion depth and the relationship between the submucosal lesion and the esophageal wall using the resected lesion as the gold standard.

RESULTS

Twenty-seven esophageal SMTs were evaluated. EUS and EICT accurately identified nine as superficial to the muscularis propria. EICT correctly identified the relation of the tumor extension and the outer esophageal wall in all 18 lesions that originated from the muscularis propria; only nine were correctly assessed by EUS (P < 0.001).

CONCLUSIONS

EICT enables improved judgment of the relation of esophageal lesions and the esophageal-mediastinal border. We propose EICT as a new, safe, effective, useful, simple and high-tolerance method for assessing the depth and relationships of esophageal submucosal lesions.