How can breast cancer continue to kill in mass numbers?

Cancer of any kind: Is a difficult disease. We have made great strides in treating many cancers, especially hodgkin lymphoma and childhood cancers, but unless detected early, before it has spread, it more likely than not will eventually cause the patient's death. In 2011, approx 230, 000 cases of invasive and approx 58, 000 cases of non invasive breast cancer were diagnosed in the us, with approx 39, 000 deaths.