Background/Aim: The lymph node ratio (LNR), defined as the ratio of metastatic to examined lymph nodes, is a prognostic indicator in gastric cancer after curative gastrectomy. However, in response to neoadjuvant chemotherapy (NAC), the absolute number of metastatic lymph nodes may decrease. Moreover, the N-stage classification after this (ypN) alone may not fully reflect residual nodal disease. We evaluated whether LNR-based stratification offers improved prognostic discrimination compared with ypN classification, using survival analysis together with time-dependent receiver operating characteristics analysis. Patients and Methods: We retrospectively analyzed 201 patients with gastric adenocarcinoma who underwent post-NAC curative (R0) gastrectomy with D2 lymphadenectomy at Kanagawa Cancer Center (March 1992 to November 2019). Patients were classified using commonly reported LNR cutoffs: low (0.25). Recurrence-free (RFS) and overall survival (OS) were evaluated. The prognostic performance of the LNR and the ypN classification was compared using multivariate Cox proportional hazards models. Results: The median follow-up period was 37.6 months. Higher LNR was associated with worse RFS and OS (pvs. low LNR: intermediate: 3.622 (1.302-10.08), p=0.017; high: 3.923 (1.154-13.34), p=0.029] and OS vs. low LNR: intermediate: 3.590 (1.341-9.606), p=0.011; high: 4.057 (1.230-13.38), p=0.021 in multivariate analysis. Conclusion: The LNR may serve as a practical postoperative risk stratification metric for recurrence and survival after NAC in patients with gastric cancer, complementing the limitations of the ypN classification.
KOMORI et al. (Fri,) studied this question.