Prospective Study on Double-Stapling End-to-End Gastroduodenostomy Billroth-I Anastomosis in Laparoscopy-Assisted Surgery for Locally Advanced Distal Gastric Cancers

Inclusion Criteria:

* Age from 18 to years (including 18 and 85years old)
* Pathological diagnosis of primary focus is gastric adenocarcinoma made by endoscopic biopsy (papillary, tubular, mucinous, signet ring cell, poorly differentiated)
* cT1-4a, N+/-, M0 at preoperative evaluation
* No peritoneal metastasis or other distant metastases of gastric carcinoma (affirmed by laparoscopic surgery and related imaging examinations)
* Expected curative resection through laparoscopic distal gastrectomy with D2 lymphadenectomy (include multiple primary lower gastric adenocarcinoma)
* Performance status of 0 or 1 on Eastern Cooperative Oncology Group scale (ECOG)
* Preoperative American Society of Anesthesiology score (ASA) classⅠ, Ⅱ or Ⅲ
* Major organs are functioning normally:

blood routine test (No blood transfusions in the last 14 days): HB≥90g/L, ANC≥1.5×109/L, PLT≥80×109/L blood biochemical examination: BIL\<1.5× upper limit of normal (ULN), ALT and AST\<2.5×ULN, Crea≤1×ULN.

\- The subject is willing to participate in this clinical trail

Exclusion Criteria:

* History of previous upper abdominal surgery (include ESD/EMR, except laparoscopic cholecystectomy)
* History of acute pancreatitis
* Regional fusion of enlarged lymph nodes by preoperative imaging (maximum diameter \>3cm)
* History of other malignant disease within past five years
* History of unstable angina, myocardial infarction, cerebral infraction, or cerebral hemorrhage within past six months
* History of continuous systematic corticosteroids therapy within past one month
* Requirement of simultaneous surgery for other disease
* Emergency surgery due to complication (bleeding, or perforation) caused by gastric cancer
* FEV1\<50% of predicted values by pulmonary function test
* Women during pregnancy or breast-feeding
* Severe mental disorder
* Participating in other clinical studies simultaneously
* Refusing to sign the informed consent for the study
* Peritoneal implant or other distant metastases by intraoperative exploration
* Unresectable due to tumor reasons by intraoperative exploration
* Distal gastric cancer surgery cannot be performed after intraoperative exploration
* Duodenal bulb has been invaded by tumor or gastroduodenostomy cannot be performed due to additional surgical resection cause by positive intraoperative frozen margin