ESR1 and neoplasm: The nomogram incorporating PIV, estrogen receptor (ER), human epidermal growth factor receptor-2 (Her2), tumor diameter, clinical node stage, and chemotherapy regimen showed excellent discrimination (training cohort area under the curve (AUC): 0.861, 95% confidence interval (CI): 0.821–0.901; validation cohort AUC: 0.815, 95% CI: 0.748–0.882).