Medical Treatment

Many women have treatment in addition to surgery, which may include radiation therapy, chemotherapy, or hormonal therapy. The decision about which additional treatments are needed is based upon the stage and type of cancer, the hormonal and HER-2/neu receptors, and patient health and preferences.

Radiation therapy is used to kill tumor cells if there are any left after surgery.

Radiation is a local treatment and therefore works only on tumor cells that are directly in its beam.

Radiation is used most often in people who have undergone conservative surgery such as lumpectomy. Conservative surgery is designed to leave as much of the breast tissue in place as possible.

Radiation therapy is usually given 5 days a week over 5-6 weeks. Each treatment takes only a few minutes.

Radiation therapy is painless and has relatively few side effects. However, it can irritate the skin or cause a burn similar to a bad sunburn in the area.

Chemotherapy consists of the administration of medications that kill cancer cells or stop them from growing. In breast cancer, three different chemotherapy strategies may be used

1. Adjuvant chemotherapy is given to people who have had curative treatment for their breast cancer, such as surgery and radiation. It is given to reduce the possibility that the cancer will return.

2. Presurgical chemotherapy is given to shrink a large tumor and/or to kill stray cancer cells. This increases the chances that surgery will get rid of the cancer completely.

3. Therapeutic chemotherapy is routinely administered to women with breast cancer that has spread beyond the confines of the breast or local area.

Most chemotherapy agents are given through an IV line, but some are given as pills.

Chemotherapy is usually given in "cycles." Each cycle includes a period of intensive treatment lasting a few days or weeks followed by a week or two of recovery. Most people with breast cancer receive at least 2, more often 4, cycles of chemotherapy to begin with. Tests are then repeated to see what effect the therapy has had on the cancer.

Chemotherapy differs from radiation in that it treats the entire body and thus may find stray tumor cells that may have migrated from the breast area.

The side effects of chemotherapy are well known. Side effects depend on which drugs are used. Many of these drugs have side effects that include loss of hair, nausea and vomiting, loss of appetite, fatigue, and low blood cell counts. Low blood counts may cause patients to be more susceptible to infections, to feel sick and tired, or to bleed more easily than usual.

Hormonal therapy may be given because breast cancers (especially those that have ample estrogen or progesterone receptors) are frequently sensitive to changes in hormones. Hormonal therapy may be given to prevent recurrence or for treatment of existing disease.

In some cases, it is beneficial to suppress a woman's natural hormones with drugs; in others, it is beneficial to add hormones. In premenopausal women, ovarian ablation (removal of the hormone effects of the ovary) may be useful. This can be accomplished with medication or surgery, less commonly with radiation.

Until recently, tamoxifen (Nolvadex), an antiestrogen, has been the most commonly prescribed hormone treatment. It is used both for breast-cancer prevention and for treatment.

Aromatase inhibitors, which block the effect of a key hormone affecting the tumor, may be more effective than tamoxifen in the adjuvant setting. These drugs: Anastrozole (Arimidex), exemestane (Aromasin), and letrozole (Femera) have a different set of side effects and risks than tamoxifen.

Aromatase inhibitors are rapidly moving into first-line hormonal-therapy regimens. In addition, they are frequently used after two or more years of tamoxifen therapy.

Fulvestrant (Faslodex) and megestrol acetate (Megace) are other drugs which may be used as hormonal therapy.

Monoclonal antibodies are antibodies against proteins in or around a cancer cell. Antibodies recognize an "invader"—in this case, a cancer cell—and attack it.

Trastuzamab (Herceptin) is an antibody against the HER-2 protein, a protein responsible for cancer cell growth in many women with breast cancer (about 30% of breast cancers).

Its role in breast-cancer therapy is evolving, but it appears that most women who are HER-2 positive and need further therapy, may benefit from this drug either in an adjuvant setting or in the setting of more advanced disease.

Another monoclonal antibody, Bevacixumab (Avastin), has been shown to have activity in the treatment of breast cancer.