Clinical Study on Using Laparoscopic Sentinel Lymph Node Navigation Combined With Dual Endoscopy Surgery for Early Gastric Cancer

Gastric cancer is a common malignant tumour worldwide, and in China, the incidence and mortality rates of gastric cancer remain high. Standardised surgical treatment is effective, but the normal structure of the stomach undergoes irreversible changes, leading to a series of adverse reactions. At the same time, some early-stage gastric cancer patients cannot have the lesions completely removed endoscopically, and conventional surgery can affect postoperative normal life. Therefore, laparoscopic and endoscopic cooperative surgery has become a focus for precise stomach-preserving surgery. Participants meeting the surgical criteria are selected, and after discussing the treatment plan with their families and signing informed consent forms, relevant examinations are completed. During surgery, lesions are explored together using laparoscopy and endoscopy, then a fluorescent tracer is injected around the lesion and the lesion boundary is marked. Fifteen minutes after injecting the fluorescent tracer, the illuminated perigastric lymph nodes are the sentinel lymph node region (SLNB), and all fluorescent lymph nodes (sentinel lymph nodes) are removed and sent for intraoperative frozen pathology. If the SLNB is negative: a dual-endoscope combined local gastric resection (endoscope combined with laparoscopic local gastric resection or a modified procedure) is performed to completely remove the lesion, ensuring a negative margin. If the SLNB is positive: immediate conversion to laparoscopic-assisted radical gastrectomy (D2 lymph node dissection) is carried out. For SLNB-negative cases, the dual-endoscope combined local gastric resection specimen is placed in a retrieval bag for full removal and examination, with the stomach wall incision then closed by suturing or using a stapler. Postoperative follow-up includes monitoring tumour outcomes and quality of life.

Inclusion Criteria: 1. Gastroscopy biopsy confirmed a solitary gastric adenocarcinoma; 2. White light endoscopy, magnifying endoscopy-image-enhanced endoscopy，(ME-IEE）, endoscopic ultrasound and enhanced CT comprehensively assessed as cT1N0M0, with no distant metastasis; 3. Assessed by MDT as unsuitable for simple ESD: including cases beyond the current guideline/consensus recommended ESD curative resection indications, or although at the endoscopic treatment border, significant fibrosis, scarring, non-lifting and other factors make complete endoscopic resection difficult and surgical function-preserving treatment has reasonable benefits; 4. Lesion maximum diameter in principle ≤5 cm; for lesions close to 5 cm, near the cardia/pylorus or expected to cause stenosis or significant gastric deformation after local resection, they are listed as key review cases before surgery, and gastric preservation path can be directly abandoned during surgery; 5. ECOG performance status score 0-1, able to tolerate general anaesthesia and laparoscopic surgery; 6. Patient fully understands the potential benefits and uncertainties of SNNS/LECS, the possible false-negative risk of ICG single tracing and intraoperative pathology, as well as the possibility of conversion/additional standard radical gastrectomy, and has signed the informed consent form. Exclusion Criteria: 1. Preoperative imaging, endoscopy or MDT suggests cT2 or above, definite lymph node metastasis or distant metastasis; 2. Pregnant or breastfeeding women; 3. Previous major upper abdominal surgery leading to expected severe adhesions, significantly affecting SLB localisation or surgical implementation; 4. Recurrent gastric cancer, multiple primary gastric cancers, or those who received preoperative radiotherapy and chemotherapy; 5. Cases that have undergone ESD removal and achieved curative resection according to eCura standards; 6. History of severe ICG allergy or deemed unsuitable by the researcher to use ICG; 7. Patients with other untreated malignant tumours, severe cardiopulmonary dysfunction, or other conditions unable to tolerate general anaesthesia and pneumoperitoneum; 8. Those unable to understand the study process or complete standard follow-up.