Abstract
BACKGROUND: The necessity of dissecting station 1 (right paracardial) and 4Sb (left gastroepiploic artery) lymph nodes (LNs) during radical distal gastrectomy for gastric cancer remains debated. This study investigated their therapeutic value for lower-third (LGC) and middle-third (MGC) gastric cancer. METHODS: This retrospective cohort study analyzed 897 patients undergoing radical distal gastrectomy (2013-2019). Metastasis rates, clinicopathological associations, multivariate analyses for risk factors and survival and therapeutic value index (TVI = metastasis frequency × 5-year survival of station-positive patients) for stations 1 and 4Sb were assessed, stratified by tumor location. RESULTS: For LGC (n = 435), station 4Sb showed a 0.46% metastasis rate and a 0% TVI. In contrast, station 1 had a 5.06% metastasis rate and a TVI of 4.14%. Multivariate survival analysis for LGC revealed that after adjusting for T and N stage, station 1 metastasis was not an independent prognostic factor for overall survival (HR 1.60, 95% CI 0.95-2.71, p = 0.078). For MGC (n = 462), station 1 metastasis was an independent prognostic factor (HR 1.75, 95% CI 1.08-2.83, p = 0.023). CONCLUSIONS: Routine dissection of station 4Sb LNs in LGC offers negligible survival benefit. Furthermore, given that station 1 metastasis is not an independent prognostic factor in LGC, its routine dissection also warrants reconsideration. These findings support a biology-driven refinement of lymphadenectomy guidelines, suggesting that omitting station 4Sb and selectively omitting station 1 in LGC may be oncologically safe. Prospective validation is crucial.