A mastectomy is surgery to remove a breast or part of a breast. It is usually done to treat breast cancer. Types of breast surgery include

• Total (simple) mastectomy - removal of breast tissue and nipple
• Modified radical mastectomy - removal of the breast, most of the lymph nodes under the arm, and often the lining over the chest muscles
• Lumpectomy - surgery to remove the tumor and a small amount of normal tissue around it

Which surgery you have depends on the stage of cancer, size of the tumor, size of the breast, and whether the lymph nodes are involved. Many women have breast reconstruction to rebuild the breast after a mastectomy.

Sometimes mastectomy is done to prevent breast cancer. Only high-risk patients have this type of surgery.

NIH: National Cancer Institute