What are breast cancer medical treatments?
Patients with breast cancer have many treatment options. Most treatments are adjusted specifically to the type of cancer and the staging group. Treatment options are being adjusted frequently and your health care provider will have the information on the current standard of care available. Treatment options should be discussed with a health care team. The following are the basic treatment modalities used in the treatment of breast cancer.
Most women with breast cancer will require surgery. Broadly, the surgical therapies for breast cancer can be divided into breast-conserving surgery and mastectomy.
This surgery will only remove part of the breast (sometimes referred to as partial mastectomy). The extent of the surgery is determined by the size and location of the tumor.
In a lumpectomy, only the breast lump and some surrounding tissue is removed. The surrounding tissue (surgical margins) are inspected for cancer cells. If no cancer cells are found, this is called "negative" or "clear margins." Frequently, radiation therapy is given after lumpectomies.
During a mastectomy (sometimes also referred to as a simple mastectomy), all the breast tissue is removed. If immediate reconstruction is considered, a skin-sparing mastectomy is sometimes performed. In this surgery, all the breast tissue is removed as well, but the overlying skin is preserved.
During this surgery, the surgeon removes the axillary lymph nodes as well as the chest wall muscle in addition to the breast. This procedure is done much less frequently than in the past, as in most cases, a modified radical mastectomy is as effective.
Modified radical mastectomy
This surgery removes the axillary lymph nodes in addition to the breast tissue. Depending on the stage of the cancer, a health care team might give someone a choice between a lumpectomy and a mastectomy. Lumpectomy allows sparing of the breast but usually requires radiation therapy afterward. If lumpectomy is indicated, long-term follow-up shows no advantage of a mastectomy over the lumpectomy.
For a small group of patients who have a very high risk of breast cancer, surgery to remove the breasts may be an option. Although this reduces the risk significantly, a small chance of developing cancer remains.
Double mastectomy is a surgical option to prevent breast cancer. This prophylactic (preventive) surgery can decrease the risk of breast cancer by about 90% for women at moderate to high risk for breast cancer.
Such an approach should be carefully discussed with a health care team.
The discussion about whether to undergo any preventive surgery should include
- genetic testing for BRCA1 or BRCA2 gene mutations,
- full review of risk factors,
- family history of cancer and specifically breast cancer, and
- other preventive options such as medications.
Radiation therapy destroys cancer cells with high energy rays. There are two ways to administer radiation therapy.
External beam radiation
This is the usual way radiation therapy is given for breast cancer. A beam of radiation is focused onto the affected area by an external machine. The extent of the treatment is determined by a health care team and is based on the surgical procedure performed and whether lymph nodes were affected or not.
The local area will usually be marked after the radiation team has determined the exact location for the treatments. Usually, the treatment is given five days a week for five to six weeks.
This form of delivering radiation uses radioactive seeds or pellets. Instead of a beam from the outside delivering the radiation, these seeds are implanted into the breast next to the cancer.
Chemotherapy is treatment of cancers with medications that travel through the bloodstream to the cancer cells. These medications are given either by intravenous injection or by mouth.
Chemotherapy can have different indications and may be performed in different settings as follows:
- Adjuvant chemotherapy: If surgery has removed all the visible cancer, there is still the possibility that cancer cells have broken off or are left behind. If chemotherapy is given to assure that these small amounts of cells are killed as well, it is called adjunct chemotherapy. Chemotherapy is not given in all cases, since some women have a very low risk of recurrence even without chemotherapy, depending upon the tumor type and characteristics.
- Neoadjuvant chemotherapy: If chemotherapy is given before surgery, it is referred to as neoadjuvant chemotherapy. Although there seems to be no advantage to long-term survival whether the therapy is given before or after surgery, there are advantages to see if the cancer responds to the therapy and by shrinking the cancer before surgical removal.
- Chemotherapy for advanced cancer: If the cancer has metastasized to distant sites in the body, chemotherapy can be used for treatment. With cases of metastatic breast cancer, the health care team will need to determine the most appropriate length of treatment.
There are many different chemotherapeutic agents that are either given alone or in combination. Usually, these drugs are given in cycles with certain treatment intervals followed by a rest period. The cycle length and rest intervals differ from drug to drug.
This therapy is often used to help reduce the risk of cancer reoccurrence after surgery, but it can also be used as adjunct treatment.
Estrogen (a hormone produced by the ovaries) promotes the growth of a few breast cancers, specifically those containing receptors for estrogen (ER positive) or progesterone (PR positive). The following drugs are used in hormone therapy:
- Tamoxifen (Nolvadex): This drug prevents estrogen from binding to estrogen receptors on breast cells.
- Toremifene (Fareston) works similar to Tamoxifen and is only indicated in metastatic breast cancer.
- Fulvestrant (Faslodex): This drug eliminates the estrogen receptor and can be used even if tamoxifen is no longer useful.
- Aromatase inhibitors: They stop estrogen production in postmenopausal women. Examples are letrozole (Femara), anastrozole (Arimidex), and exemestane (Aromasin).
BRCA-mutated breast cancer therapy
Early in 2018, the U.S. FDA approved olaparib (Lynparza) for treatment of metastatic breast cancer for patients who carry the BRCA mutation. Olaparib has already been used in ovarian cancer. The drug acts as an inhibitor of the enzyme PARP (known as a PARP-inhibitor drug), which is involved in the repair of damaged DNA. Blocking this enzyme may make it less likely to repair cancerous cells, leading to a slowdown or even stoppage of tumor growth.
Two other PARP inhibitors are approved for treating ovarian cancer but do not currently have approval in breast cancer (rucaparib [Rubraca], niraparib [Zejula]).
As we are learning more about gene changes and their involvement in causing cancer, drugs are being developed that specifically target the cancer cells. They tend to have fewer side effects than chemotherapy (as they target only the cancer cells) but usually are still used in adjunct with chemotherapy.
Whenever a disease has the potential for much harm and death, physicians search for alternative treatments. As a patient or the loved one of a patient, there may be an inclination to try everything and leave no option unexplored. The danger in this approach is usually found in the fact that the patient might not avail themselves of existing, proven therapies. One should discuss any interest in alternative treatments with a health care team and together explore the different options.