PGR and breast cancer: CAD (Computer-Assisted Diagnosis) systems are more accurate and consistent than classical visual interpretation, already being successfully used to identify the regions of interest on the investigated specimen, as well as other details: specific staining (estrogen or progesterone receptors, HER2/neu evaluation in breast cancer, Ki67 evaluation in carcinoid tumors), tumor staging, mitosis presence, vascular invasion presence and quantification, etc.