Breast cancer (BC) is the most frequent female cancer worldwide. Breast cancer (BC) is a type of cancer originating from the epithelium of the mammary gland. As most cancers, it can be invasive or noninvasive. Knowledge of the embryology and development of the mammary gland as well as the pathophysiology of breast pathology is essential in dealing with breast cancer in research and clinical routine. Prognosis of primary breast cancer has improved over the last decades because of improvements in diagnosis and treatment. Treatment of advanced breast cancer is challenging and needs personalization, knowledge in biomarkers, and multimodal treatment algorithms as well as therapeutic management of side effects and supportive care.