This investigator-initiated, randomized superiority clinical trial aims to demonstrate the clinical effectiveness of RUS GA Surgical Navigation, an endoscopic imaging treatment planning software, in patients undergoing robotic-assisted distal gastric cancer surgery. The trial will compare the experimental group using RUS GA with a control group, aiming to show an 8.7% reduction in total surgery duration. The study will involve global multicenter patient recruitment and evaluate the clinical safety and feasibility of the software, which has been shown to be reliable in previous studies.

• Investigational Medical Device: RUS GA (Endoscopic Imaging Treatment Planning Software, E04010.01)
• Clinical Trial duration: 30 months from IRB approval -Target number of subjects: Total of 330 participants

After selecting subjects and obtaining informed consent, randomization will be conducted. Robot-assisted gastrectomy will be performed using RUS GA or without software. Clinical significance will be evaluated through outpatient follow -ups for up to one month after discharge.

Inclusion Criteria:

1. Individuals diagnosed with gastric cancer and scheduled for robot-assisted gastrectomy.
2. Adults aged 20 and above who are capable of independent judgment.
3. Individuals capable of undergoing CT imaging according to the prescribed protocol.
4. Individuals who, before participating in the clinical trial, undergo an interview in a separate place, understand sufficient explanation of the purpose and content of the trial, and voluntarily sign informed consent form (approved by the Institutional Review Board)

Exclusion Criteria:

1. Vulnerable individuals (those lacking decision-making capacity, illiterate individuals, pregnant women, newborns, minors under the age of 20, etc.).
2. Patients who cannot undergo CT imaging according to the prescribed protocol before gastric cancer surgery (due to contrast agent allergies, creatinine levels exceeding 1.5 times the normal upper limit, claustrophobia, etc.).
3. Individuals whose major gastric or intra-abdominal arterial/venous structures have been altered due to previous gastric or other abdominal surgeries (however, those with a history of intra-abdominal surgery that did not affect the stomach or major blood vessels are eligible).
4. Patients with a history of residual gastric cancer from previous surgery.
5. Patients who do not consent to participate in the study or withdraw their consent.
6. Patients scheduled for simultaneous resection of other organs besides the stomach.