Accurate prognostic stratification after gastrectomy is crucial for individualized management of gastric cancer. Although examination of at least 15 lymph nodes is recommended to ensure reliable staging, this threshold is not consistently achieved in routine practice, potentially compromising prognostic accuracy. The lymph node ratio (LNR) has been proposed as an alternative nodal metric; however, its prognostic role in the context of suboptimal lymphadenectomy remains unclear. This study aimed to evaluate the prognostic impact of LNR in patients following suboptimal lymphadenectomy and to assess whether its effectiveness is influenced by the extent of nodal dissection. This retrospective single-center cohort study included 210 patients with non-metastatic gastric adenocarcinoma who underwent curative-intent gastrectomy between January 2016 and January 2021, with a predefined 5-year follow-up period. Suboptimal lymphadenectomy was defined as the retrieval of fewer than 15 lymph nodes. Overall survival (OS) was analyzed using Kaplan–Meier estimates and Cox proportional hazards models. Multivariable analysis was performed in the suboptimal lymphadenectomy group, and an interaction term (LNR × extent of lymphadenectomy) was evaluated in the full cohort. Eighty-nine patients (42.4%) underwent suboptimal lymphadenectomy. Within this group, LNR independently predicted poorer overall survival (adjusted HR 2.50, 95% CI 1.14–5.47; p = 0.022), together with increasing age. In the overall cohort, a significant interaction between LNR and the extent of lymphadenectomy was identified ( p = 0.030), indicating that the prognostic impact of LNR varies according to nodal retrieval adequacy. LNR represents an independent prognostic factor in patients following suboptimal lymphadenectomy and interacts with the extent of nodal dissection. These findings support the incorporation of LNR into postoperative risk stratification when lymph node retrieval is inadequate.
Aytin et al. (Thu,) studied this question.