If you understand how breast cancer usually spreads, then the emphasis on early detection becomes clear. The sooner breast cancer is detected, the smaller it is and the less likely it is to have spread. Small tumors found in the breast early can often be cured by simply excising them. Larger tumors will be more likely to require a mastectomy, but once the tumor has left the breast, surgery alone is not enough. Additional treatment is needed to kill the cells that have escaped. Unfortunately, the more cells that have escaped, the harder it is to cure breast cancer. The goal of breast cancer awareness and early detection is to find more tumor when they are small are treatable and prevent the larger tumor that cannot be cured.