Surgery Lumpectomy and mastectomy are the two main surgical procedures that are used to treat breast cancer. During a lumpectomy, only the tumor and some surrounding normal tissue is removed. Women usually then receive six to seven weeks of radiation therapy to destroy any remaining cancerous tissue. This is called breast conservation therapy. It is often an option for women with breast cancer, but not always.
Mastectomy is the removal of the entire breast.
For a modified radical mastectomy, surgeons remove the breast and some of the underarm lymph nodes. A radical mastectomy is the removal of the breast, the underarm lymph nodes, and the chest wall muscles under the breast. In the past, doctors believed that removing as many lymph nodes as possible would reduce the risk of cancer spreading to distant sites, improving chances of survival. Now, a more systematic method is used to discover which, if any, lymph nodes need to be removed. These substances will then be carried to the sentinel node, which is the name for the first lymph node into which the tumor drains.