Mesenteric Vascular Preconditioning Combined With Laparoscopic and Endoscopic Cooperative Surgery for Submucosal Tumor at the Gastroesophageal Junction

Single-center Prospective Clinical Study on the Application of Mesenteric Vascular Preconditioning Combined With Laparoscopic and Endoscopic Cooperative Surgery for Submucosal Tumor at the Gastroesophageal Junction (SAVE-GEJ Trial)

This study is a single-center, prospective, single-arm, exploratory clinical study (phase II exploratory trial). No parallel control group was established in the study, and all subjects who met the inclusion criteria underwent a uniform surgical treatment approach, namely, double-scope combined resection with mesenteric vascular preconditioning. The study aims to preliminarily evaluate the safety and effectiveness of this novel surgical strategy for the treatment of submucosal tumor at the gastroesophageal junction, and to provide data support for subsequent larger-scale controlled studies.

This study follows the PICO principle design, as detailed below:

Target population: Patients aged 18-80 years with gastroesophageal junction submucosal tumor, diagnosed by endoscopy, CT, and/or endoscopic ultrasonography, with a tumor diameter of 1-5cm and an upper margin ≤2cm from the esophageal dentate line, who plan to undergo surgical treatment.

Surgical approach: Pre-treatment of mesenteric vessels with combined resection using both endoscopes. Based on the distance between the upper edge of the tumor and the dentate line, the tumor is classified and the corresponding surgical procedure is adopted: Type I (involving the dentate line or lower esophagus): Pre-treatment of mesenteric vessels + Submucosal Endoscopic Tunneling Resection (STER) + laparoscopic reinforcement; Type II (≤1cm from the dentate line): Pre-treatment of mesenteric vessels + Endoscopic Submucosal Dissection (ESD) or STER surgery or Endoscopic Full-thickness Resection (EFTR) + laparoscopic reinforcement; Type III (1-2cm from the dentate line): Pre-treatment of mesenteric vessels + EFTR surgery + laparoscopic reinforcement. The distance between the tumor and the dentate line is measured endoscopically with the subject in a supine position under moderate insufflation during gastroscopy.

Clinical outcome:

Primary outcome: Evaluate the safety of this surgical protocol. The primary evaluation indicators are: conversion to open surgery rate, total operation time, number of endoscopic hemostasis attempts during the operation, hemostasis time, incidence of perioperative complications (such as bleeding, anastomotic leakage, gastroparesis, etc.), and changes in postoperative inflammatory markers in patients.

Secondary outcomes: Evaluate the oncological efficacy of the surgical regimen, including 5-year disease-free survival (DFS) and overall survival (OS). Assess the impact of the surgical regimen on patients' postoperative gastric function and quality of life, through comprehensive evaluation using upper gastrointestinal imaging, gastric function scores (such as STO22), quality of life scales (EORTC QLQ-C30), and nutritional indicators. Explore the factors related to surgical success and patient prognosis.

Inclusion Criteria:

• Aged 18 to 80 (inclusive), of either gender.
• Preoperative gastroscopy, enhanced CT, and/or endoscopic ultrasonography (EUS) examinations led to a clinical diagnosis of submucosal tumor (SMT) at the gastroesophageal junction.
• The maximum diameter of SMT is 1~5 cm (based on radiological measurements).
• The distance from the upper margin of the SMT to the dentate line of the esophagogastric junction is ≤2 cm.
• Eastern Cooperative Oncology Group (ECOG) physical status score of 0 or 1.
• Plan to undergo laparoscopic surgery, and the researcher judges that the patient is suitable for the combined surgical procedure involved in this study.
• Volunteer to participate in this study and sign a written informed consent form.

Exclusion Criteria:

• SMT that meets the absolute indications for endoscopic treatment alone (such as lesions with a diameter of <1cm that can be completely resected endoscopically).
• Patients with severe systemic diseases such as heart, lung, liver, and kidney dysfunction, who are unable to tolerate surgery or anesthesia after evaluation.
• Women who are pregnant or breastfeeding.
• Previous history of upper abdominal surgery.
• Previously received upper abdominal radiotherapy.
• Have suffered from or currently suffer from other malignant tumors within the past 5 years.
• Lesions accompanied by clear ulcers, metastasis, or lesions after neoadjuvant and conversion therapy.
• The researcher determines that there are any other situations that make the participant unsuitable for participating in this study (such as mental disorders, poor adherence, etc.)