Breast cancer occurs when cells in the breast begin to grow out of control enabling them to invade nearby tissues or spread throughout the body. Collections of these out of control tissues are called tumors. However, not all breast tumors are considered cancerous since certain types of large cells just cannot be spread or threaten a person’s life and this kind of tumor is called benign tumor. On the other hand, the tumors that can spread all throughout the body or invade nearby tissues are co...