Indication of Proximal Gastrectomy for Advanced Proximal Gastric Cancer Based on Lymph Node Metastasis at the Distal Part of the Stomach.

Objective: To suggest the possible indication of proximal gastrectomy for advanced gastric cancer located at the upper third of the stomach. Background: Proximal gastrectomy has been an alternative surgical procedure for early proximal gastric cancer due to its benefits for quality of life while maintaining oncological outcomes. However, the oncological safety of proximal gastrectomy for advanced tumors remains unclear. Methods: We retrospectively reviewed data from 878 patients who underwent radical total gastrectomy from 2003 to 2018 for pathologic T2-T4 gastric cancer in the upper third of the stomach. We identified risk factors for lymph node metastasis at the distal part of the stomach, which was not dissected in proximal gastrectomy. Subsequently, we evaluated the metastasis rate and therapeutic value index of lymph nodes at the distal part of the stomach in patients with none of these risk factors. Results: Multivariable analysis revealed that esophagogastric junction (EGJ)-tumor epicenter distance >30 mm, tumor size >70 mm, macroscopic type IV tumor, and serosal invasion were risk factors for lymph node metastasis at the distal stomach. In patients without risk factors, the therapeutic value index for any lymph nodes at the distal stomach was 0.8, suggesting that lymph node dissection could be omitted in these patients. Conclusions: EGJ-tumor epicenter distance ≤ 30 mm, tumor size ≤ 70 mm, not a macroscopic type IV tumor, and no serosal invasion could be an indication of proximal gastrectomy for advanced gastric cancer located at the upper third of the stomach.