Development of a prognostic nomogram for lymph node positive HR + /HER2 - breast cancer patients: a study of SEER database and a Chinese cohort

The hormone receptor /human epidermal growth factor receptor 2 (HR /HER2 ) breast cancer (BC) patients account for the largest proportion in all patients and are still at high risk of long-range recurrence. This current study aimed to construct a prognostic nomogram to predict 3-year and 5-year BC-specific survival (BCSS) in HR /HER2 BC patients with axillary lymph node metastasis. A total of 25,338 HR /HER2 patients with axillary lymph node-positive BC were enrolled from the Surveillance, Epidemiology and End Results (SEER) database and randomly divided into the training (n=17,738) and validation (n=7,600) cohorts using a ratio of 7:3. Univariate and multivariable Cox regression hazards were used to build a prognostic nomogram based on the training cohort. The nomogram was validated with two independent cohorts. Receiver operating characteristic (ROC) curves and calibration plots were used to evaluate the performance of the model, and Kaplan-Meier survival analyses were applied to test the clinical utility of the risk stratification system. Twelve factors including age, race, marital status, grade, T stage, N stage, radiotherapy, chemotherapy, and metastasis to the bone, brain, lung and liver were identified and incorporated to construct the nomogram (P