Recently, the concept of "Onco-metabolic surgery" has emerged, and it is a theory that if anastomosis bypassing the duodenum and upper jejunum is performed after gastrectomy in gastric cancer patients with type 2 diabetes, diabetes can be expected to improve. The authors would like to compare and analyze the effect of long bowel Luwai gastrointestinal anastomosis in gastric cancer patients with type 2 diabetes in a multicenter prospective manner with that of type 2 diabetes gastric cancer patients who underwent a conventional Luwai gastrointestinal anastomosis.

<Research Design>

1. Primary Endpoint

   • It examines whether there is a statistically significant difference in the proportion of patients with improved blood sugar control one year after surgery.

   • Here, "Improvement of blood sugar control" includes all of the following three cases (complete remission, partial remission and improvement)

     1. IMPROVEMENT: Transition from insulin injection to oral hypoglycemic agents and reduction of diabetic medication dose due to reduction of glycated hemoglobin compared to preoperative
     2. Partial remission: Stop taking diabetes medication and maintain fasting blood glucose 100 to 125 and glycated hemoglobin 6 to 6.4
     3. Complete mission: Stop taking diabetes medication and maintain less than 100 fasting blood sugar and less than 6 glycated hemoglobin

2. Secondary Endpoint

   • Whether fasting blood glucose levels and glycated hemoglobin reduction at 1,3,6,12 months after surgery between the groups were significantly different
   • Comparison of significant differences in changes in nutritional factors at 1, 3, 6, and 12 months after surgery between groups
   • A Comparison of Significant Differences in Diabetes-Related Hormone Changes in 1, 3, and 12 Months After Surgery Between Groups

<Method of research>

1. This study is a comparative study conducted with multicenter, prospective randomization.

2. How to operate

   • Before the start of surgery, the study group and the control group are selected by random assignment and the surgery is performed.
   • The target groups that met the criteria for selection of the study are randomly divided into two groups (study group: long bowel Luwai anastomosis group, and control group: existing Luwai anastomosis group). The assignment of the two groups is to contact the institution to which the entire clinical trial director belongs, that is, the research nurse at Korea University Guro Hospital, to receive a military assignment after the subject of the study is registered for each institution and before surgery.

   Randomization is performed according to a table using https://www.sealedenvelope.com/ , and in order to ensure a balanced distribution between the two groups, stratified block randomization is performed by each institution participating in this clinical trial. Therefore, the study subjects will be randomly assigned to either the research group or the control group at a ratio of 1:1 within the participating institution.

   • Research group (Long bowel Ruwai anastomosis group)

     • Laparoscopic or robotic lower subtotal resection and extensive lymph node resection
     • When performing the lower gastric subtotal resection, 70% of the total gastric volume should be resected and about 30% should be left including the bottom of the stomach.
     • When performing Luwai-type anastomosis, the length of the biliary tract pancreatic branch, which is the field finger, is 80 centimeters, and the length of the blade finger from the stomach-factory anastomosis is 80 centimeters.

   • Control (Existing Ruwai Anastomosis Group)

     • Laparoscopic or robotic lower subtotal resection (70% resection) and extensive lymph node resection
     • The length of the biliary tract pancreatic branch, which is a field finger, is 20 cm when performing the Luwai-type anastomosis according to the existing method Meter, the length of the blade from the upper-factory anastomosis part is 40 centimeters, and the upper-factory and factory- perform a jejunal anastomosis. Therefore, the difference in length between the two groups' diverted small intestine branches is 100 cm It's a meter.

3. Analysis method Among the patients to be studied in this study, sex and age of the study group scheduled to perform a long bowel Luwai anastomosis and the control group patients scheduled to perform a conventional Luwai anastomosis, the medical history period of diabetes before surgery, body obesity at 1, 3, and 12 months before and after surgery, fasting blood sugar levels, and glycated hemoglobin levels are compared. Blood is collected for the preoperative and postoperative tests (30 minutes, 60 minutes, 120 minutes after loading) in the study group and the control group and the hormone and related components (insulin, C-peptide, Adiponectin, Leptin, Ghrelin, GLP-1, GIP, PYY) that are expected to be related to metabolic control and diabetes improvement effects are investigated and analyzed.

In addition, the degree of improvement in blood sugar control (no improvement, improvement: switching from insulin injection to oral hypoglycemic agents and reducing the dose of diabetic drugs, partial remission: maintaining fasting blood sugar from 100 to 125 without taking diabetic drugs, maintaining glycated hemoglobin 6 to 6.4 and complete remission: maintaining less than 100 fasting blood sugar without taking diabetic drugs) in the two groups is compared to examine the difference in blood sugar control effects according to changes in the length of anastomosis. In addition, we would like to conduct an analysis regarding the improvement of the plasma control effect to find out which factors can be the necessary requirements for improving diabetes control.

Inclusion Criteria:

• Clinical Stage I Gastric Cancer
• a patient aged 20 to 80
• Dx of Type 2 Diabetes
• Preoperative BMI ≥ 23 kg/m2

Exclusion Criteria:

• If you have a history of cancer other than gastric cancer in the last five years
• If you received chemotherapy treatment before gastric cancer surgery
• Preoperative advanced gastric cancer is diagnosed, or gastric total resection is performed in the upper part
• If you have a history of malabsorption

Age, gender, weight, BMI, Inbody (Option), duration of diabetes and diabetes treatment drugs, comorbidities other than diabetes, blood tests