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Patient Education: Diseases Conditions Treatments & Procedures

Breast Cancer

Type of Treatment Therapies

Radiation Therapy
Radiation therapy is the use of high energy x-rays to kill cancer cells. This is considered a local therapy as it only treats breast cancers cells that may be present within the breast or axillary lymph nodes, not the rest of the body.

The most common method of radiation therapy to treat breast cancer is called external beam radiation. External beam radiation is most often given as a course or series of daily (Monday through Friday) treatments over a few weeks.

Radiation therapy is almost always recommended along with breast conserving therapy (lumpectomy) to try and ensure that all cancer cells within the breast are destroyed. In certain circumstances, it may also be used after mastectomy.

Chemotherapy
Chemotherapy is the use of drugs to stop the growth of cancer cells in the body. The goal of chemotherapy is to treat any cancer cells that may have been left after surgery and have traveled to other parts of the body. These cells are generally too small to be found by scans or blood tests. Based on the stage of breast cancer and the characteristics of the tumor, your oncologist may recommend treatment with chemotherapy. Usually, you are given more than one chemotherapy drug in order to attack the cancer cells in different ways. This is called combination therapy. Your oncologist will prescribe the best drugs for your situation.

Chemotherapy for early stage (stages 1 and 2) breast cancer is usually started a few weeks after surgery. In general, chemotherapy is usually finished before radiation, and is not given at the same time as radiation.

Chemotherapy given before surgery (called preoperative or neoadjuvant chemotherapy) is used to shrink bigger tumors or those that cannot easily be treated by surgery at the time they are first found. The goal of this treatment is to shrink the tumors so that the tumor can then be removed by surgery.

In general, chemotherapy is associated with side-effects. Your oncologist will discuss these in detail with you. The decision to offer chemotherapy is only made if your oncologist determines that you will have a reduced risk of your breast cancer returning and you can tolerate the side effects associated with the treatment.

Hormone Therapy
Some tumors are affected by chemicals that occur naturally in our bodies. Estrogen and progesterone, female hormones produced by the body, can help promote the growth of a breast tumor. Hormone therapy is used to stop estrogen and progesterone from entering the breast cancer cell. This prevents the tumor from growing or can slow down the process. Almost two-thirds of all breast cancers are estrogen receptor positive (ER+) and/or progesterone receptor positive (PR+). If your tumor is ER+ or (PR+), your oncologist may recommend a form of hormone therapy as part of your adjuvant treatment plan.

Biological Therapy
Biological or targeted therapies are the newest forms of treatment for breast cancer. These drugs act like antibodies to destroy proteins that make breast cancer cells grow faster. Biological drugs cause few side effects as they specifically target breast cancer cells and not the normal healthy cells in your body. HER2 is a receptor that has been identified as promoting breast cancer growth. HER2 positive breast cancer patients have too many Her2 receptors on the cancer cell. This is associated with a more aggressive form of breast cancer. If you test positive for the gene, you may be offered this type of treatment.

A drug called Herceptin (Trastuzumab) has been designed to attack HER2 receptors in order to slow the progression of the disease. Trastuzumab works by blocking HER2 receptors which can stop the growth of breast cancer cells. Trastuzumab also stimulates the body's immune system to help destroy the cancer cells. For the treatment of early stage breast cancer, it is given by intravenous injection along with and/or after chemotherapy. Trastuzumab has been found to be an effective treatment to reduce the risk of breast cancer recurrence in patients with early stage, HER2 positive breast cancer.

Visit the Breast Care Group at Odette Cancer Centre