Comparison of Predictive Performance of Three Lymph Node Staging Systems in Colorectal Signet Ring Cell Carcinoma Based on Machine Learning Model

Lymph node status is a critical prognostic predictor for patients; however, the prognosis of colorectal signet-ring cell carcinoma (SRCC) has garnered limited attention. This study investigates the prognostic predictive capacity of the log odds of positive lymph nodes (LODDS), lymph node ratio (LNR), and pN staging in SRCC patients using machine learning models (Random Forest, XGBoost, and Neural Network) alongside competing risk models. Relevant data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. For the machine learning models, prognostic factors for cancer-specific survival (CSS) were identified through univariate and multivariate Cox regression analyses, followed by the application of three machine learning methods-XGBoost, RF, and NN-to ascertain the optimal lymph node staging system. In the competing risk model, univariate and multivariate competing risk analyses were employed to identify prognostic factors, and a nomogram was constructed to predict the prognosis of SRCC patients. The area under the receiver operating characteristic curve (AUC-ROC) and calibration curves were utilized to assess the model's performance. A total of 2,409 SRCC patients were included in this study. To validate the effectiveness of the model, an additional cohort of 15,122 colorectal cancer patients, excluding SRCC cases, was included for external validation. Both the machine learning models and the competing risk nomogram exhibited strong performance in predicting survival outcomes. Compared to pN staging, the LODDS staging systems demonstrated superior prognostic capability. Upon evaluation, machine learning models and competing risk models achieved excellent predictive performance characterized by good discrimination, calibration, and interpretability. Our findings may assist in informing clinical decision-making for patients.