MKI67 and breast cancer: After dimensionality reduction analysis by using the independent sample t test and LASSO regression, we screened out 15 ultrasound radiomics features as imaging markers, and not only established but also validated six advanced machine learning classifiers (DT, RF, SVM, LR, NB and XGBoost) for identifying the Ki-67 status of BC, with AUC values ranging from 0.679 to 1.000 and 0.615 to 0.798 in the training and test sets, respectively.