Breast cancer is the most common cancer among women in both developed and developing countries, with an estimated 1.38 million new cases diagnosed, and it remains the leading cause of death among women worldwide.Its natural history has been the most extensively studied in the world, and has led to the introduction of screening, which in developed countries has led to a reduction in mortality rates, as well as to improvements in treatment.Multidisciplinary management is essential. There is no human cancer whose clinical expression is as variable and whose evolution as unpredictable as that of breast cancer. The most important event is the occurrence of metastases, which signal distant dissemination and seriously compromise vital prognosis.