Prospective multicenter feasibility study of laparoscopic sentinel basin dissection for organ preserving surgery in gastric cancer: Quality control study for phase III trial.

143 Background: Clinical application of sentinel node biopsy (SNB) in early gastric cancer (EGC) is still controversial even though promising multicenter trial result with minimal false negatives was already reported from Japan. Moreover laparoscopic approach is considered as minimally invasive in addition to organ preserving surgery. Therefore we conducted this study as a prerequisite quality control for phase III trial. Methods: Laparoscopic SBD was performed in patients with preoperative stage T1-2N0 and tumor size less than 4cm in maximal diameter. Intraoperative endoscopic submucosal injection of Technetium 99m-Human Serum Albumin and indocyanine green was done. All removed sentinel basin nodes (SBN) were investigated with intraoperative frozen Hematoxylin Eosin (HE) stain. Postoperative permanent HE stain was done for SBNs and non-SBNs. Strict checklist consisting of essential 7 steps during laparoscopic SBD was made as the quality control study for phase III trial. Ten cases completion of all essential steps in checklist were defined as qualified institution. Results: Seven institutions participated and 112 patients were enrolled in this study. However 4 patients were excluded due to screening failure. SB detection and SBD was performed in 100 of the 108. Lymph node metastases were found in 11 patients at postoperative permanent HE staining and SBD contained metastatic lymph nodes in 11 patients. The detection rate of SB was 92.6% with mean number of SB and SBN was 1.68 and 9.56. Sensitivity and accuracy were 100% in this study. Frozen results of SBN were compatible with permanent reports except one patient who had one SBN with micrometastasis. As the quality control of each institution for phase III trial, 13 to 20 cases were needed based on our strict checklist. Conclusions: Laparoscopic SBD is feasible and improve the sensitivity comparing to the previous study. This study suggests the promising phase III trial of laparoscopic SBD for minimally invasive and organ preserving surgery in EGC after qualifying participating institutions. Clinical trial information: NCT01544413.