The Prognostic Performance of Log Odds of Positive Lymph Nodes in Patients with Esophageal Squamous Cell Carcinoma: A Population Study of the US SEER Database and a Chinese Single-Institution Cohort

Abstract

Background: The purpose of this study was to assess the prognostic performance of log odds of positive lymph nodes (LODDS) compared with pN stage and lymph node ratio (LNR), in patients with esophageal squamous cell carcinoma (ESCC). Method: A total of 1,144 patients diagnosed with ESCC from the Surveillance, Epidemiology and End Results (SEER) database and 930 patients from our validation cohort were eligible. Kaplan-Meier plot and multivariate Cox proportional hazards models were conducted to investigate the prognostic value of pN, LNR and LODDS classifications. The homogeneity, discriminatory ability, and monotonicity of these variables were evaluated using the linear trend χ2 test, likelihood ratio χ2 test, Akaike information criterion (AIC) and consistency index (C-index) to determine the potential superiorities. Results: The prognostic cut-off values were determined as -1.49, and -0.55 (P< 0.001). Univariate analyses showed that pN, LNR and LODDS stages significantly influenced the overall survival (OS) of patients (all P < 0.001). Multivariate analyses confirmed that LODDS was an independent prognostic indicator in both the SEER database and our validation cohort. Subgroup analyses identified the LODDS as an important prognostic factor over the ability of distinguish heterogeneous patients within various groups in both two independent databases. Furthermore, the model incorporated LODDS had the highest C-index and the smallest AIC value among the three investigated nodal classifications of both cohorts. Conclusion: The novel LODDS classification showed a better prognostic performance than the traditional N or LNR classifications in patients with ESCC. It can serve as the auxiliary prognostic factor out of the better performance and apply to the evaluation of the lymph node status devoting for precise staging and better survival. Funding Statement: This work was supported by National Natural Science Foundation of China, Clinical Trial Project of Tianjin Medical University, Bethune Charitable Foundation-Excelsior Surgical Fund, and Science and Technology Project of Tianjin Municipal Health Commission. Declaration of Interests: No potential conflicts of interest are disclosed. Ethics Approval Statement: This study obtained approval from the Ethical Committee and institutional review board of Tianjin Medical University Cancer Institute and Hospital.