Breast Cancer Basics
Breast Cancer Basics—this information provides general guidelines for treatment. Each individual may vary, and the final recommendation of your breast specialist may be different for this reason.
Breast cancer is a malignant tumor made up of one of the cells found in breast tissue. The cancer originated as a normal cell in the breast, then went through a series of mutations until it becomes a cancer. Cancer is different from normal cells in that when a cancer cell bumps up against a neighboring cell, it does not stop growing as a normal cell would do. It invades the adjacent cell, and the one next to it, and so on until it encounters a blood vessel or lymphatic channel where it can gain access to the rest of the body. Carcinoma-in-situ has not yet made the final mutation into becoming invasive. If a breast cancer will spread from its original site in the breast, it is likely to spread first to the lymph nodes underneath the armpit on the same side.
The primary treatment for breast cancer is surgery. Breast cancer surgeries have two main goals: 1) to remove all of the cancer with a clear margin and 2) to evaluate the lymph nodes for cancer.
The first goal can be achieved in one of two surgical procedures:
- mastectomy, or removing all of the breast tissue on that side, or
- lumpectomy, or removing the tumor with a margin of normal tissue to assure complete removal of the cancer (also known as breast conservation).
Lumpectomy is only available to women whose tumor is small enough to allow for complete removal with clear margins and a cosmetically acceptable breast will remain. When lumpectomy is chosen, follow-up radiation therapy is necessary to make this option as equally likely to cure the cancer as mastectomy.
Evaluation of the lymph nodes for cancer is done by a procedure know as sentinel lymph node biopsy. In this procedure, the first lymph node or nodes to drain the breast are identified by injection into the breast of a radioactive tracer and/or blue dye which are then detected in the armpit by a Geiger counter or by direct vision of the dye. When these lymph nodes contain cancer, it is often necessary to perform a procedure called axillary dissection. In this procedure, a pad of fat containing lymph nodes is removed from the armpit allowing numerous lymph nodes to be examined pathologically to determine the number of cancerous nodes.
Chemotherapy involves treatment with medications which kill rapidly dividing cells such as cancer cells. It is usually recommended after surgery is completed and the pathology results are available. Not all patients will require chemotherapy, but the choice of surgical procedure will not affect this recommendation (i.e. a woman who has mastectomy procedure is not less likely to require chemotherapy than a woman who has lumpectomy). Chemotherapy may be recommended before surgery if the cancer is large in an attempt to shrink the tumor to allow for lumpectomy.
