Although no individual feature among the 38 texture features calculated from dbPET and whole-body PET/CT BC images was significantly associated with all tumor characteristics of interest, the PCs derived by PCA of these texture features obtained with both modalities had good predictive power for T-category, N-category, molecular subtype (Luminal A vs. others), and Ki67 level. The gene discussed is MKI67; the disease is neoplasm.