Prospective Multicenter Feasibility Study of Laparoscopic Sentinel Basin Dissection for Organ Preserving Surgery in Gastric Cancer: Quality Control Study for Surgical Standardization Prior to Phase III Trial

The clinical application of sentinel node biopsies in early gastric cancer is still controversial even though it appears promising. This study was conducted as a prerequisite quality control for surgical standardization of laparoscopic sentinel basin dissection (SBD) prior to the initiation of a phase III trial. Laparoscopic SBD was performed in patients with preoperative stage T1-2N0 and tumor size <4 cm in diameter. Intraoperative endoscopic submucosal injection of a standardized dual tracer was administered. All retrieved sentinel basin nodes (SBN) were investigated with intraoperative frozen hematoxylin and eosin (H&E) staining. A strict checklist consisting of 7 essential steps was followed during laparoscopic SBD as the quality control study for a phase III trial. Completion of all essential steps in the checklist for 10 cases was used to define a qualified institution. Seven institutions participated and 112 patients were enrolled in this study. However, 4 patients were excluded owing to screening failure. The mean number of cases required for institutional qualification was 15 cases (range, 13–20 cases). Sentinel basins (SB) were detected and dissected in 100 of the 108 patients (92.6%); the median number of SB and SBN was 2 and 7, respectively. Lymph node metastases were detected in 10 patients by postoperative permanent H&E staining and they were detected by SBD in all 10 patients. Frozen results of SBN were compatible with permanent staining reports. Laparoscopic SBD is feasible and demonstrated improved sensitivity in detecting metastatic lymph nodes compared to the previous study. A future phase III randomized trial comparing laparoscopic SBD with organ-preserving gastrectomy and laparoscopic standard gastrectomy seems promising for qualified institutions.