Prognostic Significance of Lymph Node Dissection Along the Upper-third-stomach in Patients With Lower-third Gastric Cancer

Background/aim The extent of lymph node (LN) dissection is defined according to the type of gastrectomy regardless of tumor location in recent Japanese gastric cancer treatment guidelines. However, lymphatic flow from lower-third stomach mainly drain to supra- and infra-pyloric nodes, as well as to partially lesser curvature nodes along the descending limb of the left gastric artery. In this study, we evaluated the prognostic impact of LN dissection of right paracardial (No. 1) and left greater curvature (No. 4sb) nodes in gastric cancer of lower-third stomach (LGC). Patients and methods A total of 239 patients with LGC who underwent distal gastrectomy at our hospital were retrospectively analyzed. The therapeutic value index (TVI) of each node was calculated by multiplying the incidence of LN metastasis by the 5-year survival rate of patients with metastasis to each nodal station. Results The incidence of No. 1 LN metastasis was 4.5% (positive/negative; 5/110 cases, unknown or no description; 129 cases). The 5-year survival rate of patients with metastasis to the node was 0%, and consequently the TVI of No. 1 LN station was "0". Similarly, the TVI of No. 4sb was found to be "0". Conclusion Survival benefit of dissection of No. 1 and No. 4sb LNs was presumed to be extremely low, suggesting that dissection of these two LNs could be omitted in LGC patients when undergoing distal gastrectomy.