Comparison Of Short-term Outcomes Between OGT-assisted Overlap Esophagojejunostomy And Traditional Overlap Method In Patients With Siewert III/II Esophagogastric Junction Cancer Or Gastric Cancer

Methods Objectives This trial is a prospective, multicenter trial for OGT-assisted overlap esophagojejunostomy and traditional overlap method during totally laparoscopic total gastrectomy for Siewert III/II esophagogastric junction cancer and gastric cancer. The primary purpose of this study is to evaluate the time of oesophagojejunostomy of OGT method compared with traditional overlap method for Siewert III/II esophagogastric junction cancer and gastric cancer. The second purpose is to evaluate the success rate of inserting anvil fork into esophageal lumen at first attempt, attempts of inserting anvil fork into esophagus, early postoperative complications,recovery course and compare the postoperative hospital stay of the patients enrolled in this study.

Study design This trial is a prospective, multicenter, randomized, controlled, open, and superiority trial comparing the safety of OGT method during TLTG for Siewert III /II esophagogastric junction cancer and gastric cancer compared with traditional overlap method .

Participating surgeons To participate in this trial, the responsible surgeons should meet the following qualifications: first, completing at least 50 cases of TLTG with D2 lymphadenectomy;second, passing the blind review of surgery video. Briefly, the applicants should provide the videos of TLTG with traditional overlap and OGT method in recent 3 months (three cases each) to the CLASS Research Council.CLASS Research Council will select two videos of traditional overlap and OGT method separately, and randomly appoint three experts to peer review blindly. When three experts unanimously approved it, the applicant will be permitted to participate in this study as a researcher.

Sample size calculation This is a superiority verification study on clinical efficiency, with the time of oesophagojejunostomy as the main index for efficiency evaluation. Our center's early OGT Overlap esophagojejunal anastomosis takes only 21 minutes, compared to 30-32 minutes for the conventional technique. The experimental group has a mean standard deviation of 6, while the control group has a mean standard deviation of 8. The ratio of the two groups is 1:1, and the superiority threshold is set at 7. With a one-sided error of 0.05 and a power test of 0.8, we calculated the required sample size for each group as 156 cases. Given a maximum dropout rate of about 10%, the final sample size for each group was set at 172 cases, totaling 344 cases.

Inclusion criteria Aged 18-75 years; Primary lesion is pathologically diagnosed as gastric adenocarcinoma; Expected to live more than 1 year; Tumor located located in gastroesophageal junction (GEJ) involve esophagus no more than 2cm, or in the upper, upper to middle, or entire stomach, and intend to perform laparoscopic total gastrectomy with D2 lymphadenectomy No history of upper abdominal surgery (except for laparoscopic cholecystectomy); Preoperative performance status (ECOG, Eastern Cooperative Oncology Group) of 0 or 1; Preoperative ASA (American Society of Anesthesiologists) scoring: I-III; Sufficient organ functions; Written informed consent.