Non-exposure omental sealing endoscopic full-thickness resection (NEOS-EFTR) with sentinel node navigation surgery for early gastric cancer: a case series.

Background: Various non-exposurelaparoscopic and endoscopic cooperative surgery (NE-LECS) with sentinel node navigation surgery (SNNS) have been proposed for patients with early gastric cancer (EGC) exceeding the absolute indications for endoscopic submucosal dissection (ESD). However, the specific technical aspects of NE-LECS with SNNS require further clarification. This study proposes and evaluates a novel non-exposure omental sealing endoscopic full-thickness resection (NEOS-EFTR) with SNNS for EGC. Case Description: This study included 5 patients who underwent NEOS-EFTR with SNNS between July 2025 and September 2025. Clinical data and treatment outcomes were collected and analyzed. The mean tumor size was 2.7 cm (range: 2.1-3.6 cm), with an R0 resection achieved in all cases. SNNS were successfully performed in every patient. The mean operation time was 155 minutes (range: 140-185 minutes), and the mean postoperative hospital stay was 5.4 days (range: 4-9 days). No complications of grade I or above (Clavien-Dindo ≥ I) were recorded. During a mean follow-up of 3.4 months (range: 3-4), there was no evidence of tumor recurrence or metastasis, though this reflects only short-term observation given the limited follow-up duration. Although gastric emptying was transiently prolonged at the 1-week assessment, it returned to near-normal levels by 3 months postoperatively. Patient reported quality of life and functional scores remained well-preserved throughout. This study was registered with ClinicalTrials.gov (NCT06788548). Conclusions: NEOS-EFTR with SNNS offers a promising alternative for managing EGC that extends beyond the absolute indications for ESD, presenting certain advantages over conventional NE-LECS. The preliminary efficacy and safety profiles observed require further validation.