Development and Validation of a Prognostic Model for Short-Term Outcomes in NDM- MAC

Purpose: The objective of this study was to develop a nomogram that can be used to predict the 3-year overall survival (OS) of patients with non-distant metastatic mucinous adenocarcinoma of the colon (NDM-MAC). Methods: : From the SEER (Surveillance, Epidemiology, and End Results) database, a total of 1675 patients with NDM-MAC were extracted and utilized as a training cohort. A multivariate COX regression model was developed and visualized as a nomogram in the training cohort. Furthermore, an additional 207 patients were enlisted from the China-Japan Union Hospital, Jilin University, to constitute an external validation cohort. Decision curve analysis (DCA) curves, C-index, AUC values, and internal and external validation calibration curves were used to assess the established model. The training cohort underwent retrospective scoring using a nomogram. The X-Tile software was utilized to determine the two optimal cutoff values, to develop a risk assessment model. Results: : Age, T stage, N stage, Tumor site, and the quantity of harvested lymph nodes (Harvested LN) were included as five variables influencing the 3-year OS to construct the nomogram. The calibration curves of the nomogram demonstrate a good consistency between the predicted OS and the actual OS. The C-index for both internal validation and external validation was 0.703 (P < 0.001) and 0.699 (P < 0.001). NDM-MAC patients were divided into three categories according to the risk assessment model. The survival statistics showed a substantial difference (P<0.001) between the subgroups. Conclusion: In conclusion, this study developed a nomogram for NDM-MAC that included 5 variables.