Prognostic Performance of Three Lymph-Node Staging Systems on Gastric Signet-Ring-Cell Carcinoma

SIMPLE SUMMARY: Signet-ring-cell carcinoma (SRCC) is a specific subtype of gastric cancer with a lower incidence and poor prognosis. At the same time, the prognosis of early SRCC and late SRCC remains controversial. Early SRCC and SRCC have different prognostic features, especially lymph-node metastasis. Therefore, the accurate assessment of lymph-node metastasis is important for SRCC. We retrospectively analyzed the prognostic value of different lymph-node staging systems for early and advanced SRCCs. We demonstrated that the predictive performance of log odds of positive lymph nodes (LODDS) is superior to pN-stage and lymph-node metastasis rate (LNR) regardless of early or late SRCC, and is an independent risk factor associated with patient outcomes. This provides a theoretical basis for the further exploration of lymph-node metastasis in SRCC. ABSTRACT: Background: The lymph-node staging system can predict the prognosis of gastric signet-ring-cell carcinoma (SRCC). However, there are significant differences in lymph-node status between early SRCC and advanced SRCC. Additionally, the optimal system for early and advanced SRCC remains unknown. Methods: This study retrospectively analyzed 693 SRCC patients who underwent radical resection in the Department of Gastrointestinal Surgery, Harbin Medical University Cancer Hospital. The predicted performance of three lymph-node staging systems, including pN staging, lymph-node metastasis rate (LNR), and log odds of positive lymph nodes (LODDS), was compared using the receiver characteristic operating curve (ROC) and c-index. The Kaplan–Meier method and the log-rank test analyzed the overall survival of patients. The Cox risk regression model identified independent risk factors associated with patient outcomes. The nomogram was made by R studio. Results: The 693 SRCC included 165 early SRCC and 528 advanced SRCC. ROC showed that LODDS had better predictive performance than pN and LNR in predicting prognosis regardless of early or advanced SRCC. LODDS can be used to predict the prognosis of early and advanced SRCC and was an independent risk factor associated with patient outcomes (p = 0.002, p < 0.001). Furthermore, the nomogram constructed by LODDS and clinicopathological features had good predictive performance. Conclusions: LODDS showed clear prognostic superiority over both pN and LNR in early and advanced SRCC.