Radical Mastectomy is the removal of the breast and surrounding tissue. In most cases, mastectomy is required in order to remove cancerous tissue from the body. The extent of tissue removed is determined by the amount of cancer present in your body. A Radical Mastectomy is the most extensive form of breast cancer surgery. It calls for the complete removal not only of the breast, but also of the lymph nodes, as well as part or possibly all of the chest muscle that lies underneath the breast. Lymph nodes are small junctions that join the vessels that make up the lymphatic system. The lymphatic system circulates a bodily fluid called lymph in the same way that the circulatory system carries blood. Your doctor has recommended that you undergo a radical mastectomy because the cancer in your breast may have begun to move into the lymph nodes under your arm as well as into your chest muscle. This procedure may result in the loss of some muscle strength in the arm on the effected side of the body and will permanently change the outward shape and appearance of your chest. So make sure that you ask your doctor to carefully explain the reasons behind this recommendation.