ESR1 and neoplasm: Using multinomial regression analyses, we demonstrated that the ER/HER2 combined subtypes were the best predictor of the clustering pattern (AIC = 59.881), followed by the ER status (AIC = 63.195), the tumor phenotype (AIC = 70.293), the PR status (AIC = 74.277), and the HER2 status (AIC = 82.575).