A Prognostic Model Based on the Log Odds Ratio of Positive Lymph Nodes Predicts Prognosis of Patients with Rectal Cancer

Abstract

Objective: This study aimed to compare the prognostic value of rectal cancer by comparing different lymph node staging systems, and a nomogram was constructed based on superior lymph node staging.

Methods: Overall, 8700 patients with rectal cancer was obtained from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. The area under the curve (AUC), the C index, and the Akaike informativeness criteria (AIC) were used to examine the predict ability of various lymph node staging methods. Prognostic indicators were assessed using univariate and multivariate COX regression, and further correlation nomograms were created after the data were randomly split into training and validation cohorts. To evaluate the effectiveness of the model, the C index, calibration curves, decision curves (DCA), and receiver operating characteristic curve (ROC) were used. We ran Kaplan-Meier survival analyses to look for variations in risk classification.

Results: While compared to the N-stage positive lymph node ratio (LNR), the log odds ratio of positive lymph nodes (LODDS) had the highest predictive effectiveness. Multifactorial COX regression analyses were used to create nomograms for overall survival (OS) and cancer-specific survival (CSS). The C indices of OS and CSS for this model were considerably higher than those for TNM staging in the training cohort. The created nomograms demonstrated good efficacy based on ROC, rectification, and decision curves. Kaplan-Meier survival analysis revealed notable variations in patient survival across various patient strata.

Conclusions: Compared to AJCC staging, the LODDS-based nomograms have a more accurate predictive effectiveness in predicting OS and CSS in patients with rectal cancer.

Keywords: Colon cancer; LODDS; Nomogram; SEER; Survival analysis.

Fig. 1

Kaplan-Meier analysis of overall survival (OS) and cancer-specific survival (CSS) of rectal cancer patients based on different lymph node staging modalities OS: a Kaplan-Meier curves based on N staging; b Kaplan-Meier curves based on LNR staging; and c Kaplan-Meier curves based on LODDS staging. CSS: d Kaplan-Meier curves based on N staging; e Kaplan-Meier curves based on LNR staging; and f Kaplan-Meier curves based on LODDS staging

Fig. 2

Training cohort-based construction of prognostic nomograms predicting 1-, 3-, and 5-year prognosis in patients with rectal cancer: a nomograms predicting overall survival (OS) and b nomograms predicting cancer-specific survival (CSS)

Fig. 3

Correction curves for nomograms constructed on the basis of overall survival (OS). a–c Correction curves for the training cohort at 1, 3, and 5 years, in that order. d–f Correction curves for the validation cohort at 1, 3, and 5 years, in that order

Fig. 4

Correction curves for nomograms constructed based on cancer-specific survival (CSS). a–c Correction curves for the training cohort at 1, 3, and 5 years, in that order. d–f Correction curves for the validation cohort at 1, 3, and 5 years, in that order

Fig. 5

Receiver operating characteristic curve (ROC) based on nomograms constructed for overall survival (OS). a–c ROC curves for the training cohort at 1, 3, and 5 years, in that order. d–f ROC curves for the validation cohort at 1, 3, and 5 years, in that order

Fig. 6

Receiver operating characteristic curve (ROC) based on nomograms constructed for cancer-specific survival (CSS). a–c ROC curves for the training cohort at 1, 3, and 5 years, in that order; d–f ROC curves for the validation cohort at 1, 3, and 5 years, in that order

Fig. 7

Decision curve analysis (DCA) based on the nomograms constructed for overall survival (OS). a–c DCA at 1, 3, and 5 years for the training cohort in order. d–f DCA at 1, 3, and 5 years for the validation cohort in order

Fig. 8

Decision curve analysis (DCA) constructed based on cancer-specific survival (CSS). a–c DCA at 1, 3, and 5 years for the training cohort in order. d–f DCA at 1, 3, and 5 years for the validation cohort in order

Fig. 9

Kaplan-Meier survival analyses based on the nomograms’ hazard scores for nomogram high-scoring group (NSH), nomogram medium-scoring group (NSM), and nomogram low-scoring group (NSL). a Kaplan-Meier curves in the OS training set. b Kaplan-Meier curves in the CSS training set. c Kaplan-Meier curves in the OS validation set. d Kaplan-Meier curves in the CSS validation set