Inclusion Criteria

Inclusion Criteria for prospective study participants

- Patients must have documented diagnosis of gastric cancer

- Patients receiving laparoscopic gastric cancer surgery without preoperative evidence
of serosal invasion and distant lymph node metastasis as determined by preoperative
CT-scan, upper endoscopy, and endoscopic ultrasound.

- Patients who have received comprehensive explanation about the planned study,
understand and accept all the terms of the study and willingly give consent to
participate in all the required elements of the study

Inclusion Criteria for retrospective study participants

- Any patients who underwent robotic gastrectomy in Korea

Exclusion Criteria for prospective study participants

- Patients without mental competence

- Patients who are illiterate

- Patients who are pregnant

- Patients < 20 years old

Exclusion Criteria for retrospective study participants