A mastectomy is a surgical procedure in which all or a portion of the breast is removed as part of treatment for breast cancer. In some cases, mastectomy is performed prophylactically (to prevent cancer from occurring) in women with a high risk for developing breast cancer.
Surgical treatment for breast cancer is divided into two categories: breast-conserving therapy (BCT), including lumpectomy, or mastectomy. BCT involves removing the least possible amount of breast tissue when removing breast cancer, and usually includes adjuvant (additional) therapy after surgery, most often radiation therapy.
When all or most of the breast tissue is removed, breast reconstruction surgery may be performed to rebuild the breast. Reconstruction may be performed at the time of the mastectomy or at a later time.
There are several types of mastectomy procedures, including:
Total (or simple) mastectomy
The removal of the entire breast, including the nipple, the areola, and most of the overlying skin.
Modified radical mastectomy
The removal of the entire breast, including the nipple, the areola, the overlying skin, and the lining over the chest muscles. In addition, some of the lymph nodes under the arm, also called the axillary lymph nodes, may be removed. The bean-shaped lymph nodes under the arm drain the lymphatic vessels from the upper arms, the majority of the breast, the neck, and the underarm regions. Often, breast cancer spreads to these lymph nodes, thereby entering the lymphatic system and allowing the cancer to spread to other parts of the body. In some cases, part of the chest wall muscle is also removed.
The removal of the entire breast, including the nipple, the areola, the overlying skin, the lymph nodes under the arm, and the chest muscles. For many years, this was the standard operation. However, today a radical mastectomy is rarely performed and is only recommended when the breast cancer has spread to the chest muscles.
In this procedure, the breast tissue, nipple and areola are removed, but most of the skin over the breast is saved. This type of surgery appears to be similar to modified radical mastectomy in effectiveness for many women. It is used only when breast reconstruction is performed immediately after a mastectomy and may not be suitable for tumors that are large or near the skin surface.
This is similar to the skin-sparing mastectomy, and it is sometimes referred to as a "total skin-sparing mastectomy." All of the breast tissue, including the ducts going all the way up to the nipple and areola, are removed, but the skin of the nipple and areola is preserved. The tissues under and around the nipple and areola are carefully cut away and examined by a pathologist. If no breast cancer cells are found close to the nipple and areola, they can be preserved. Otherwise, nipple-sparing mastectomy is not recommended.
A mastectomy may be performed as part of treatment for breast cancer.
Women with a high risk for developing breast cancer, such as those with the BRCA1 or BRCA2 gene (tumor suppressor genes associated with breast cancer) along with other increased risks, may choose to undergo prophylactic mastectomy.
The type of surgical procedure performed for breast cancer depends on the type and extent of cancer involved. If the cancerous lump is small and localized, a lumpectomy, which is a type of BCT, may be performed, rather than a mastectomy. However, if the tumor is large with respect to the size of the breast, if it involves more than one area of the breast, or if there are contraindications to radiation therapy, the doctor most likely will recommend a mastectomy. The size of the breast involved may also influence the choice of procedure.