Background
Young breast cancer (YBC) patients demonstrate a heightened propensity for regional lymph node metastasis (RLNM) in contrast to cohorts across varying age demographics. The aim of our study was to identify clinicopathologic prognostic variables in YBC patients with RLNM and construct a practical and reliable nomogram for the prediction of overall survival (OS) using the Surveillance, Epidemiology, and End Results (SEER) database.
Methods
Young individuals (≤40 years) with a diagnosis of breast cancer with RLNM were recognized from the SEER database between 2010 and 2015, and further randomly split into two cohorts: the training set (n=4,497) and the validation set (n=1,927). We first performed univariate and multivariate Cox regression analyses to confirm independent survival predictors of OS. A novel prognostic nomogram was developed and evaluated using Harrell’s concordance index (C-index), receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). To make a clear distinction between high- and low-risk patients in terms of patient survival, Kaplan-Meier survival curves were assessed using the log-rank test.
Results
Nine risk factors were found as independent prognostic variables in predicting OS, including race, grade, histology, surgery, radiation, molecular subtype, American Joint Committee on Cancer (AJCC) stage 7
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edition, T stage, and N stage. The C-index values of our nomogram were 0.786 [95% confidence interval (CI): 0.767–0.805] and 0.791 (95% CI: 0.760–0.822) in our training and validation groups, respectively. The ROC curves demonstrated sufficient discriminating ability, while the predicted and real survival rates were fairly consistent, as shown by the calibration plots. The prediction model had a higher net benefit and acceptable clinical value, as shown by the DCA curves.
Conclusions
In YBC patients with RLNM, we successfully established a unique nomogram to forecast the 2-, 3-, and 5-year OS. Clinicians may utilize this nomogram to pinpoint patients at higher risk and provide them with appropriate customized therapies.