Introduction

Subepithelial lesions (SELs) are a common incidental finding in the gastrointestinal tract during endoscopy. Endoscopic ultrasonography (EUS) is the best tool to characterize SELs features and in several cases it allows anatomopathological diagnosis after fine-needle biopsy (FNB) or aspiration (FNA) (1). The indication and technique for endoscopic resection of SELs depend on the type, size, depth of invasion and location (1). Superficial SELs can be resected using endoscopic submucosal dissection (ESD) (2) and others can even be removed by endoscopic mucosal resection (EMR), such as neuroendocrine tumors (NETs) ≤ 10 mm (3).

Aims & Methods

The aim of this study is to assess the endoscopic management of SEL. A unicentric retrospective study was performed. There were collected the LSE endoscopically removed in an advanced endoscopy center between 2017 and 2024. The resection technique was at the discretion of the endoscopist. Those LSE that required surgical treatment were excluded.

Results

50 lesions were included, the main characteristics are described in table 1.
In bloc resection (R0) was achieved in 45 SELs (90%). There were 5 cases (10%) of fragmentated resection (R1), 2 (40%) resected by ESD, 1 hybrid (20%) and 2 (40%) with hot snare. The mean size of R1 lesions was 17.2 mm (SD +/- 14.0). The histology and location were: 3 rectal NETs (60%) and 2 gastric fibroid polyps (40%).
The histopathological result of 13 SELs (26%) revealed focal contact with the deep margin. 12 (92.3%) were NETs located: 8 (66.7%) in rectum, 3 (25%) in duodenum and 1 (8.3%) gastric.
USE was performed in 21 cases (42%). In 8 LSE (38.1%) FNA was performed, and only in 3 (37.5%) was the histopathological sample representative: 1 GIST (33.3%) and 2 NETs (66.7%). 18 (85.7%) of them were located in the muscularis mucosa or submucosa. 2 LSE (9.5%) involved the muscular layer: 1 GIST (50%) and 1 fibroid polyp (50%). Both cases were resected using ESD and a perforation was documented during the procedure in each.
There were 10 (18%) complications registered: 7 bleeding (70%), 2 perforations (20%) and 1 gastrostomy (10%) to retrieve the lesion. 7 of them (70%) required endoscopic treatment, 2 (20%) surgical treatment, and in 1 case (10%) no treatment was needed. ESD presented a higher tendency of complication rates compared to the other techniques.
In 20 patients (40%) a revision endoscopy was performed, only 1 (5%) recurrence of a gastric NET was registered one year after the resection.

Conclusion

In our experience the most frequent SELs are gastric NETs and the main resection technique is L-EMR which achieves high rates of R0 with low complications. ESD is the second most used technique with a higher tendency for complication rates. The risk of recurrence after resection appears to be low.

References

• Deprez, Pierre H et al. “Endoscopic management of subepithelial lesions including neuroendocrine neoplasms: European Society of Gastrointestinal Endoscopy (ESGE) Guideline.” Endoscopy vol. 54,4 (2022): 412-429. doi:10.1055/a-1751-5742
• Ma, Xiao-Xin et al. “Endoscopic treatment and management of rectal neuroendocrine tumors less than 10 mm in diameter.” World journal of gastrointestinal endoscopy vol. 15,2 (2023): 19-31. doi:10.4253/wjge.v15.i2.19
• Santos-Antunes, João et al. “Retrospective analysis of the outcomes of endoscopic submucosal dissection for the diagnosis and treatment of subepithelial lesions in a center with high expertise.” Annals of gastroenterology vol. 35,1 (2022): 68-73. doi:10.20524/aog.2021.0675

Introduction

Gastrointestinal stromal tumors (GIST) are the most common malignant subepithelial lesions (SELs) found in the gastrointestinal tract. Due to GIST’s notable features including vascularity and deep location, endoscopic ultrasound (EUS) is the first-line diagnostic approach. Three models, color-doppler EUS, power-doppler EUS, and e-FLOW EUS, are useful for real-time vascularity detection; however, they are not effective for fine and slow flow vessel detection. Therefore, contrast enhanced EUS (CE-EUS) is proposed as a first-line approach. Nevertheless, the use of contrast may be detrimental, thus limited to some patients. To avoid contrast-related adverse events, a novel diagnostic method known as detective flow imaging endoscopic ultrasonography (DFI-EUS) has emerged.

Aims & Methods

To evaluate the utility of DFI-EUS in the diagnosis and differentiation of gastrointestinal SELs (GIST and leiomyomas) in comparison to CE-EUS.
A single-center, prospective, diagnostic study was conducted between December/2022 and October/2023 at IECED, Ecuador. The study protocol was approved by the Institutional Review Board and was conducted in accordance with the Declaration of Helsinki. Patients ≥18 years old with a suspected diagnosis of gastrointestinal SELs were enrolled for EUS vascularity assessment. Patients with contraindication for contrast agent administration, any clinical condition rendering EUS-DFI or CE-EUS unfeasible, pregnant and nursing were excluded. First, SELs’ assessment was performed by two expert endosonographers (blinded to patient’s clinical information) using DFI-EUS, followed by a CE-EUS examination (using Sulphur hexafluoride contrast agent) for diagnostic confirmation. The identification rate along with diagnostic accuracy of DFI-EUS and CE-EUS based on histopathological confirmation was the primary endpoint. The type of vascularization (microvascular/microvascular) along with endosonographic appearance (hyper/hypovascular) were also recorded.

Results

A total of 24 patients were included, comprising 54.2% females. The examined lesions consisted of 70.8% GIST and 29.1% leiomyoma. Predominantly, lesions were found in the stomach (91.7%) and within the muscularis propria layer (91.7%). All GIST were hypoechoic and mainly heterogeneous, larger than leiomyoma in size (>2 cm; p < 0.001). Tortuous vessels were significantly identified in GIST (p 0.045). Both CE-EUS (94.1%; p 0.003) and DFI-EUS (94.1%; p< 0.001) successfully detected GIST (Table 1). The overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of DFI-EUS was comparable with CE-EUS with rates of 94.12% vs 94.12, 100% vs 99.64%, 100% vs 99.85% and 87.5% vs 99.64%, respectively (Table 2). A strong inter-rater agreement between CE-EUS vs DFI-EUS was detected with a kappa of 0.903 (p<.001).

Conclusion

DFI-EUS proves to be a reliable diagnostic tool, exhibiting high diagnostic accuracy, comparable to that of CE-EUS in the differentiation of GIST and SELs in the gastrointestinal tract. Larger multicenter studies are necessary to position this alternative for SELs' differentiation in clinical practice.

References

1. Yamashita Y, Ashida R, Tamura T, Shimokawa T, Yamazaki H, Kawaji Y, Tamura T, Hatamaru K, Itonaga M, Kitano M. Novel Technique of Endoscopic Ultrasonography for the Differential Diagnosis of Gallbladder Lesions and Intraductal Papillary Mucinous Neoplasms: A Single-Center Prospective Study. Diagnostics (Basel). 2023 Jun 21;13(13):2132. doi: 10.3390/diagnostics13132132. PMID: 37443527; PMCID: PMC10341113.
2. Yamashita Y, Yoshikawa T, Yamazaki H, Kawaji Y, et al. A Novel Endoscopic Ultrasonography Imaging Technique for Depicting Microcirculation in Pancreatobiliary Lesions without the Need for Contrast-Enhancement: A Prospective Exploratory Study. Diagnostics (Basel). 2021 Oct 30;11(11):2018. doi: 10.3390/diagnostics11112018. PMID: 34829364; PMCID: PMC8621279.
3. Casali PG, Blay JY, Abecassis N, Bajpai J, et al; ESMO Guidelines Committee, EURACAN and GENTURIS. Electronic address: clinicalguidelines@esmo.org. Gastrointestinal stromal tumours: ESMO-EURACAN-GENTURIS Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2022 Jan;33(1):20-33. doi: 10.1016/j.annonc.2021.09.005. Epub 2021 Sep 21. No abstract available. PubMed ID: 34560242

Disclosure

Carlos Robles-Medranda is a key opinion leader and consultant for Pentax Medical, Steris, Medtronic, Motus, Micro-tech, G-Tech Medical Supply, CREO Medical, EndoSound, and mdconsgroup.
The other authors declare no conflict of interest.

Introduction

Complete excision of upper gastrointestinal sub-epithelial lesions (SELs) eliminates diagnostic uncertainty, obviates the need for surveillance and may be necessary for definitive diagnosis and management. Current guidelines lack precision and cohesion, and surgery is associated with significant morbidity. Herein, we describe and report on the outcomes of our SEL algorithm for endoscopic (SAFE) resection.

Aims & Methods

SELs were enrolled prospectively over 115 months until March 2023. All underwent axial (CT) imaging and endoscopic-ultrasonography (EUS) to exclude a large exophytic component or invasion into local structures, and assess for muscularis propria involvement.

Results

106 SELs were resected (mean age 60.6±13.4, 51.9% male; 41 oesophageal, 65 gastric). Oesophageal SELs underwent ESD (n=22) or STER if MP involvement was suspected (n=19). Gastric SELs underwent STER (n=6 at cardia), ESD (n=47) or exposing-EFTR (n=12). Technical success was 97.6% and 92.3% respectively. Five (7.7%) were completed laparoscopically due to deep and broad full-thickness involvement. Five (7.7%) required laparoscopic gastrotomy and surgical retrieval after successful resection and closure due to a large lesion size (mean 47 mm). There was no delayed bleeding, perforation or recurrence at a median of 13 months.

Conclusion

Upper GI SELs are effectively and safely treated by endoscopic resection. The SAFE approach provides a framework that facilitates structured decision-making. Oesophageal SELs suspected to involve the MP should undergo STER. Gastric SELs can be best managed by ESD with a view to proceed to exposing-EFTR. A laparoscopic UGI surgeon should be available in case surgical retrieval of the specimen or laparoscopic completion is required.

Disclosure

Michael J. Bourke: Research Support: Olympus, Cook Medical, Boston Scientific.