Treatment plans for breast cancer are developed based on several factors. The type and stage of the cancer, the sensitivity of the cancer to certain hormones, and the medical history of the patient are all taken into consideration. Whether or not the cancer overexpresses the HER2/neu gene can also determine appropriate treatment.
Treatment plans usually include surgery to remove the cancer. Some type of chemotherapy (drug therapy) or radiation therapy to aid the success of the surgery often follows. This is known as adjuvant or neoadjuvant therapy. The ultimate aim of all therapies is to increase long-term survival rates and to hopefully lead to recovery.
If possible, the primary treatment for breast cancer is surgery, either a lumpectomy or mastectomy.
During a lumpectomy, the surgeon removes the tumor and a small margin of normal tissue around it. A lumpectomy is usually effective on small tumors. This way they can be removed without involving too much surrounding tissue.
A mastectomy can be either simple or radical. A simple mastectomy (also called "partial mastectomy”) involves removing all of the breast tissue. The breast tissue includes skin, fatty tissue, lobules, and ducts. A radical mastectomy (also called "total mastectomy") also removes the chest wall muscles and the surrounding lymph nodes in the armpit.
In addition to surgery, breast cancer treatments usually include drug or radiation therapies. These are called adjuvant therapies. Neoadjuvant therapy treatments are used before surgery to shrink large tumors and make the surgery easier or even possible in some cases. Adjuvant therapy treatments are applied after the surgery to try to ensure that all malignant cells in the body are killed. Both are intended to increase long-term, disease-free survival rates. These therapies may include:
- biological or targeted therapy
- hormone therapy
In some cases, these therapies may be combined. The decision of which therapy to use will depend on many factors. The patient's age, the size and type of the tumor and its cells, and whether it has spread to the lymph nodes are all weighed. How the cancer reacts to certain hormones is another factor. The human epidermal growth factor receptor 2 (HER2/neu) status must also be considered. Below are summaries of the four major adjuvant therapies.
Biological or Targeted Therapies
If the breast cancer cells make an excess of HER2/neu (a genetic change that can trigger cancer cell growth), a biologic therapy called trastuzumab (Herceptin) may be necessary.
Herceptin can stop the growth of the cancer by inhibiting the actions of the HER2 proteins on cancer cells. Herceptin is often used along with chemotherapy or hormone therapy. It’s known as a "targeted therapy" because it kills only the cancer cells and does not damage any other cells. Other therapies, such as lapatinib (Tykerb), also target specific parts of tumors.
There are now hundreds of chemotherapy drugs that have been approved by the FDA for use in breast cancer treatments. These compounds may be taken by injection or in pill form.
Chemotherapy offers several benefits. It not only destroys cancer cells in the breast, but it also kills any cancer cells that are in the blood or have spread to other parts of the body. When used before surgery, chemotherapy can shrink the size of large tumors. This makes the surgery simpler for the surgeon and sometimes can make it possible to surgically remove a previously inoperable tumor. Finally, when it comes to earlier stages of breast cancer, chemotherapy is known to reduce the risk of recurrence and to lengthen survival.
There are many drawbacks to chemotherapy. There can be short-term, possibly severe side effects. There is also a slight chance of some long-term complications and secondary diseases due to the chemotherapy. However, most breast cancer patients and their doctors decide the potential, long-term benefits of chemotherapy usually outweigh the risks.
If tests show that the cancer cells have receptors on their surface for the hormones estrogen and/or progestin, that patient is considered "receptor-positive" and likely to benefit from hormone therapy. For receptor-positive women, hormone therapy will most likely be part of their cancer treatment.
Using high-powered, targeted X-rays to kill cancer cells can reduce the risk of cancer recurrence. Radiation is commonly used to destroy any cells that escaped the surgery. Radiation is regularly used for high-risk women after a mastectomy. Radiation is also used:
- when a tumor is 2 or more inches across
- if multiple lymph nodes were involved
- if the tumor had invaded the chest muscles
Radiation therapy can be delivered in two forms. External beam radiation is delivered by an X-ray machine. Internal seed radiation is implanted next to the tumor site with a needle or catheter.
When about a month has passed after surgery, radiation treatments can begin. These may continue as often as daily for up to two months. If chemotherapy is also part of the patient's treatment, radiation will frequently come after the chemotherapy is finished to allow the patient to recover from any chemo-related side effects. If hormone therapy will be used instead of chemotherapy, radiation therapy need not be delayed.