Breast cancer and its treatments. A silhouette of a woman with a cut of the brain with the pituitary gland. The pituitary gland stimulates the secretion of estrogen by the ovary (uterus in frontal section), which will attach to the estrogen receptors of cancer cells (bottom center). On the silhouette a mammary gland with the axillary ganglia that relate to it. A first zoom starts from this gland to show the anatomical structure of the mammary gland with a main galactophore duct receiving the lobules, themselves made of acinus. An enlarged acinus is seen in section. A cancerous tumor is located on the main milk duct. In the foreground, zoom of a blood vessel surrounding cancer cells seen in section the tumor with its many vessels in the background. The HER2 receptor (green), EGFR (pink) and the estrogen receptor (orange) are present on the cancer cell whose nucleus is cut to show the mitotic spindle. A strand of DNA in the replication phase is extracted from a chromosome.