Clinical Significance of Intra-operative Gastroscopy for Tumor Localization in Totally Laparoscopic Partial Gastrectomy.

BACKGROUND: Tumor localization during totally laparoscopic gastrectomy is challenging owing to the invisibility of tumors on the serosal surface. We aimed to evaluate the clinical significance of intra-operative gastroscopy in totally laparoscopic partial gastrectomy. METHODS: We reviewed 1084 gastric cancer patients who underwent either intra- or extracorporeal partial gastrectomy between 2014 and 2018. The intracorporeal group with intra-operative gastroscopy (intra-operative gastroscopy group, n = 187), the intracorporeal group without intra-operative gastroscopy (non-intra-operative gastroscopy group, n = 267), and the extracorporeal group (n = 630) were evaluated for the adequacy of surgical resection margins. We assessed whether total gastrectomy could be avoided according to the performance of intra-operative gastroscopy if the tumor was located within 3-5 cm away from the gastroesophageal junction. RESULTS: The proximal margin positivity was lesser in the intra-operative gastroscopy group than in the non-intra-operative gastroscopy group (0% versus 2.2%; P = 0.045) but similar to that in the extracorporeal group (0% versus 0.6%; P = 0.579). The number of cases with proximal resection margins < 1 cm was lower in the intra-operative gastroscopy group than in the non-intra-operative gastroscopy group (3.7% versus 9.4%; P = 0.025) but comparable with that in the extracorporeal group (3.7% versus 4.1%; P = 0.815). Among 94 patients with lesions located within 3-5 cm apart from the gastroesophageal junction, the intra-operative gastroscopy group (n = 47) had fewer patients who underwent total gastrectomy than the non-intra-operative gastroscopy group (n = 47) (12.8% versus 44.7%; P = 0.001). Intra-operative gastroscopy was the only independent factor that prevented total gastrectomy (P = 0.001). CONCLUSION: Intra-operative gastroscopy can provide margin safety during intracorporeal partial gastrectomy, avoiding unnecessary total gastrectomy.