Sentinel Node Resection With or Without LECS After Noncurative ESD for EGC

Endoscopic submucosal dissection (ESD) is the recommended treatment for early gastric cancer (EGC) who are fullfillling the criteria based on international guidelines. After ESD, some resections are classified as non-curative because of factors such as non radicality (especially when the deep margin is positive for cancer), lymphovascular invasion or deep submucosal invasion Sm>1. In such cases, guidelines recommend complementary gastrectomy and lymphadenectomy. Gastrectomy is known to carry a risk for severe complications in about 9-22 % of cases. Furthermore, up to 2/3 of patients are found to have no remaining tumor in the stomach or regional nodes after surgery.

In this trial, Indocyanine Green (ICG)-guided lymphadenectomy including sentinel node resection, with or without complementary laparoscopic and endoscopic cooperative surgery (LECS) will be tested as a less invasive treatment option. For patients with radically resected EGC, ICG-guided lymphadenectomy alone will be performed. In patients with deep margin positive EGC, ICG-guided lymphadenectomy and LECS will be performed.

ICG-guided lymphadenectomy is performed by first injecting 100 times diluted ICG in four quadrants in the submucosa around the tumor scar with gastroscopy. After 15 minutes, the draining nodes will be visualized with laparoscopy, and locally resected. LECS is performed by endoscopic marking of the scar followed circumferential mucosal cutting, trimming, and perforation of the stomach followed by full-thickness resection of the scar with laparoscopy. After resection, the resected specimen will be taken out and the stomach defect sutured laparoscopically.

After the procedure, the patient will be presented at a multidisciplinary tumor board. If only clinical follow-up is recommended, the patient will be followed closely with gastroscopy and computer tomography (CT) scan every 3 months for the first year.

Inclusion criteria

• EGC previously treated with ESD according to current guidelines (differentiated adenocarcinoma, not ulcerative, of any size, differentiated adenocarcinoma ulcerative </=3cm, undifferentiated adenocarcinoma not ulcerative </=2cm)
• Non curative resection

• Lymphovascular invasion
• Non-radical resection vertical margin
• deep submucosal invasion
• Signed informed consent

Exclusion criteria

• Location within 2 cm from cardia or pylorus
• Non-curative resection with only non-radicality horizontal margin
• Inoperative because of severe comorbidities
• Previous radiotherapy to the upper abdomen
• Pregnancy
• Allergy to ICG
• Inability to provide informed consent due to cognitive impairment, language barrier, or other reasons impairing understanding and autonomous decision-making.