Complete Mesogastric Excision Compared with Conventional D2 in Laparoscopic Gastrectomy for Locally Advanced Gastric Cancer: Safety and Efficacy Analysis of a Randomized Clinical Trial

Abstract

IMPORTANCE: Implementation of complete mesogastric excision in gastric cancer surgery, named D2 lymphadenectomy plus complete mesogastric excision (D2+CME), was proposed as a novel optimal procedure. However, the safety and efficacy of D2+CME remain uncertain. OBJECTIVE: To compare short-term outcomes of patients with advanced gastric cancer after D2+CME or conventional D2 in laparoscopic gastrectomy. DESIGN, SETTING, AND PARTICIPANTS: Between September 2014 and June 2018, a prospective, randomized, parallel-controlled trial was conducted at a tertiary referral teaching hospital (Department of Gastrointestinal Surgery, Tongji Hospital, Wuhan, China). Patients between 18 to 75 years of age with locally advanced gastric cancer (cT2-4a,N0/+,M0) were enrolled and randomized. The surgical outcomes and postoperative data were compared between the groups in a modified intention-to-treat (mITT) analysis. INTERVENTIONS: Participants were randomized to undergo either D2+CME (n=243) or conventional D2 (n=243) procedure. MAIN OUTCOMES AND MEASURES: The primary end point was 3-year disease-free survival rate. The current study presented surgical outcomes, 30-day postoperative morbidity and mortality, postoperative recovery indexes. RESULTS: In total, 486 participants were randomized in this study. Among them, 243 were assigned to D2 group and 243 were assigned to D2+CME group. After postsurgical exclusions, 338 patients were included in the modified intention-to-treat analysis, which comprised 169 patients (111 men and 58 women; mean [SD] age, 54•5 [9•3] years) in the D2 group and 169 patients (102 men and 67 women; mean [SD] age, 54•8 [9•5] years) in the D2+CME group. Patients in D2+CME group showed less intraoperative blood loss (median [IQR]; 15•0 [23•0] ml in D2+CME vs. 37•0 [33•5] ml in D2, p<0•0001), more lymph node harvesting (median [IQR]; 34 [16] lymph nodes in D2+CME vs. 27 [13] lymph nodes in D2, p<0•0001) and earlier postoperative flatus (p=0•009) than those in D2 group. The overall postoperative complication rate was comparable between the two groups (20•1% in D2+CME vs. 16•0% in D2, p=0•322), however, patients in D2+CME group were less likely to have severe complications (Clavien-Dindo Classification grade ≥IIIa: 4 in D2+CME vs. 9 in D2, p=0•041). No mortality occurred in either group. CONCLUSION: D2+CME is associated with advantages in intraoperative blood loss, lymph nodes harvest and postoperative flatus duration, and could provide better surgical safety than conventional D2 in laparoscopic gastrectomy. TRIAL REGISTRATION: ClinicalTrials.gov; NCT01978444 FUNDING STATEMENT: This work was supported by grants from the National Natural Science Foundation of China, Grant numbers: 81171927, 81372324, 81874185. DECLARATION OF INTERESTS: The authors have no conflicts of interest to disclose. ETHICS APPROVAL STATEMENT: The study was approved by the Tongji Hospital Ethics Committee (TJ-C20130811). All patients signed an informed consent document to participate in this study.