This study is a single-center, phase 2a exploratory clinical study based on IDEAL framework. The intraoperative and postoperative complications were analyzed to evaluate the safety, feasibility and clinical efficacy of single-port robot-assisted gastric tumor resection.

The study assessed the intraoperative adverse events (device-related and/or procedure-related), postoperative complications, perioperative recovery outcomes, surgical specimen quality, and pathological indices of Single-port robot-assisted radical gastrectomy for gastric cancer.

Inclusion Criteria:

• (1) Age: 18-75 years; (2) Histologically confirmed gastric adenocarcinoma by endoscopic biopsy; (3) Preoperatively staged as either endoscopically unresectable T1, or cT2-4a with or without nodal involvement (N-/+), and no distant metastasis (M0), according to the 7th edition of the AJCC Cancer Staging Manual; (4) Eligible for potentially curative surgical resection; (5) Eastern Cooperative Oncology Group (ECOG) performance status score of 0-1; (6) American Society of Anesthesiologists (ASA) physical status classification of I-III; (7) Provision of written informed consent.

Exclusion Criteria:

• (1) Pregnant or lactating women; (2) Severe psychiatric disorder; (3) History of prior upper abdominal surgery; (4) Previous gastrectomy, endoscopic submucosal dissection (ESD), or endoscopic mucosal resection (EMR); (5) Preoperative imaging showing regional lymphadenopathy with lymph node(s) larger than 3 cm in diameter; (6) History of another primary malignancy within the past 5 years; (7) Prior neoadjuvant chemotherapy or radiotherapy; (8) History of cerebrovascular or cardiovascular event (e.g., stroke or myocardial infarction) within the past 6 months; (9) Systemic corticosteroid use for more than one month within the past month; (10) Requirement for concomitant surgery for other conditions; (11) Need for emergency surgery due to gastric cancer-related complications (e.g., bleeding, obstruction, or perforation); (12) Participation in another interventional clinical trial previously; (13) Active severe infectious disease; (14) Severe systemic disease.