• It was confirmed that the laparoscopic surgery decreases the postoperative pain and reduces the recovery periods in the various surgical fields such as cholecystectomy and colectomy etc. Also, there are clinical evidences that the laparoscopic surgery is applicable to malignant tumor according to the development of surgical techniques and medical instruments.
• In case of early stage of gastric cancer, as the diverse clinical evidences, the gastrectomy has been commonly applied, however, the opening surgery is still applied for advanced gastric cancer due to lack of clinical evidence.
• In Korea, approximately 38% of patients who undergo surgery for gastric cancer are diagnosed by T2-T3 (AJCC 6th edition) (www.i-kgca.or.kr, National gastric cancer registration business in 2009). There are various clinical evidences to apply laparoscopic surgery to the patients, however, most of them are retrospective or cohort study results.
• For the clinical application of surgical treatment regarding locally advanced gastric cancer using laparoscopic surgical technique, it requires the confirmation of definite execution for laparoscopic gastrectomy and D2 lymph node dissection and the safety of surgery and oncological usefulness should be verified.
• In order for this, it is only possible to confirm through the comparison of short-term surgical results (complications, mortalities, operative time and duration of hospitalization etc) and long-term results (survival rates and recurrence rates etc) between laparoscopic surgery and opening surgery based on the multicenter large-sized randomized prospective study with current standard treatment.

Participating Surgeons

• Prior to this clinical trial, only the surgeons who are considered to have the standardization by participating the assignment entitled with "KLASS-02-QC: Standardization of D2 Lymphadenectomy and Surgical Quality Control for KLASS-02 Trial"(ClinicalTrials.gov No: NCT01283893).

Patients Registration

• It is required to ensure that the patients meet the inclusion criteria for this clinical trial, are free from any items of exclusion criteria, are explained about the participation in the clinical trial along with the informed consent forms.
• After rechecking the patients with the registration check list by accessing the web-based randomized program provided from Ajou University clinical trial center.

Randomization

• The registration randomization should be done with 1:1 ratio for each researcher.
• Baseline number (BN) should be provided to the subjects in the order of acquisition of informed consent form. Based on the subjects who are selected as the appropriate subjects in the end, the allocation number (AN) shall be provided in the order of randomized allocation table.

Procedure

• Operations are performed according to the allocated group.

Adjuvant Treatment

• If it is under Stage II and Stage III in the final postoperative pathology, the adjuvant chemotherapy based on 5-FU.

Evaluation of efficacy and safety

• 3-year Relapse free survival rate and overall survival rate of the patients who undergo laparoscopic and open subtotal gastrectomy and D2 lymph node dissection.
• Analysis of recovery after laparoscopic and open subtotal gastrectomy and D2 lymph node dissection.
• Postoperative complications of the patients who undergo laparoscopic and open subtotal gastrectomy and D2 lymph node dissection within postoperative 3 weeks and later.
• The quality of life at preoperative, postoperative 25 days and 1 years using recovery index such as recovery of postoperative intestinal hypermotility, meals and duration of hospitalization, EORTC-C30 and STO22 questionnaire between the patients who underwent laparoscopic and open subtotal gastrectomy and D2 lymph node dissection.

Inclusion Criteria:

• The patient from over 20 years to under 80 years
• The patient with the capability for ECOG (Eastern Cooperative Oncology Group performance status) is ranged between 0 and 1
• The patient included between ASA score (American society of anesthesiology) class I and III
• The patient who is diagnosed as gastric adenocarcinoma under preoperative endoscopic biopsy
• The patient who is diagnosed as locally advanced gastric cancer with the suspicious infiltration of over muscular layer without infiltration on adjacent organs, and without or with lymph node metastasis limited to perigastric or around stomach left gastric artery at the preoperative examination.
• The patient who is suitable for subtotal resection in the preoperative examination
• The patient who is fully explained about purpose of trial and contents prior to the participation into this study and signed on the informed consent approved by Institutional Review Board according to own opinion

Exclusion Criteria:

• The patient who shows distant metastasis under preoperative examination
• The patient with medical history for gastrectomy in the past
• The patient with complication (complete obstruction and perforation) by gastric cancer
• The patient who undergoes anticancer or radiologic therapy prior to the operation or who undergoes endoscopic submucous dissection for currently diagnosed gastric cancer
• The patient who undergoes surgery or anti-cancer radiologic therapy for primary cancer within 5 years
• Vulnerable patients (lack of capacity for decision making, pregnant women (or under planning))
• The patient who has participated into another clinical trial within recent 6 months or who is participating into another trial
• The patient with double cancer of activity and synchronization