Breast cancer is a cancer that starts in the tissues of the breast. There are two main types of breast cancer:
In rare cases, breast cancer can start in other areas of the breast.
Breast cancer may be invasive or noninvasive. Invasive means it has spread from the milk duct or lobule to other tissues in the breast. Noninvasive means it has not yet invaded other breast tissue. Noninvasive breast cancer is called "in situ."
Many breast cancers are sensitive to the hormone estrogen. This means that estrogen causes the breast cancer tumor to grow. Such cancers have estrogen receptors on the surface of their cells. They are called estrogen receptor-positive cancer or ER-positive cancer.
Some women have what is called HER2-positive breast cancer. HER2 refers to a gene that helps cells grow, divide, and repair themselves. When cells (including cancer cells) have too many copies of this gene, they grow faster. Historically, women with HER2-positive breast cancer have a more aggressive disease and a higher risk that the disease will return (recur) than women who do not have this type. However, this may be changing with specifically targeted treatments against HER2.
Cancer - breast; Carcinoma - ductal; Carcinoma - lobular; DCIS; LCIS; HER2-positive breast cancer; ER-positive breast cancer; Ductal carcinoma in situ; Lobular carcinoma in situ
Over the course of a lifetime, 1 in 8 women will be diagnosed with breast cancer.
Risk factors you cannot change include:
Other risk factors include:
Breast implants, using antiperspirants, and wearing underwire bras do not raise your risk for breast cancer. There is no evidence of a direct link between breast cancer and pesticides.
The National Cancer Institute provides an online tool to help you figure out your risk of breast cancer. See: www.cancer.gov/bcrisktool
Early breast cancer usually does not cause symptoms. This is why regular breast exams are important. As the cancer grows, symptoms may include:
Men can get breast cancer, too. Symptoms include breast lump and breast pain and tenderness.
Symptoms of advanced breast cancer may include:
The doctor will ask you about your symptoms and risk factors. Then the doctor will perform a physical exam, which includes both breasts, armpits, and the neck and chest area.
Tests used to diagnose and monitor patients with breast cancer may include:
If your doctor learns that you do have breast cancer, more tests will be done to see if the cancer has spread. This is called staging. Staging helps guide future treatment and follow-up and gives you some idea of what to expect in the future.
Breast cancer stages range from 0 to IV. The higher the staging number, the more advanced the cancer.
Treatment is based on many factors, including:
In general, cancer treatments may include:
Hormonal therapy is prescribed to women with ER-positive breast cancer to block certain hormones that fuel cancer growth.
Targeted therapy, also called biologic therapy, is a newer type of cancer treatment. This therapy uses special anticancer drugs that target certain changes in a cell that can lead to cancer. One such drug is trastuzumab (Herceptin). It may be used for women with HER2-positive breast cancer.
Cancer treatment may be local or systemic.
Most women receive a combination of treatments. For women with stage I, II, or III breast cancer, the main goal is to treat the cancer and prevent it from returning (curing). For women with stage IV cancer, the goal is to improve symptoms and help them live longer. In most cases, stage IV breast cancer cannot be cured.
After treatment, some women will continue to take medications such as tamoxifen for a period of time. All women will continue to have blood tests, mammograms, and other tests after treatment.
Women who have had a mastectomy may have reconstructive breast surgery, either at the same time as the mastectomy or later.
Talking about your disease and treatment with others who share common experiences and problems can be helpful. See: Cancer support group
New, improved treatments are helping persons with breast cancer live longer than ever before. However, even with treatment, breast cancer can spread to other parts of the body. Sometimes, cancer returns even after the entire tumor is removed and nearby lymph nodes are found to be cancer-free.
How well you do after being treated for breast cancer depends on many things. The more advanced your cancer, the poorer the outcome. Other factors used to determine the risk for recurrence and the likelihood of successful treatment include:
After considering all of the above, your doctor can discuss your risk of having a recurrence of breast cancer.
You may experience side effects or complications from cancer treatment. For example, radiation therapy may cause temporary swelling of the breast (lymphedema), and aches and pains around the area.
Lymphedema may start 6 to 8 weeks after surgery or after radiation treatment for cancer.
It can also start very slowly after your cancer treatment is over. You may not notice symptoms until 18 to 24 months after treatment. Sometimes it can take years to develop.
Ask your doctor about the side effects you may have during treatment.
Contact your health care provider for an appointment if:
Also call your health care provider if you develop symptoms after being treated for breast cancer, such as:
Tamoxifen is approved for breast cancer prevention in women aged 35 and older who are at high risk. Discuss this with your doctor.
Women at very high risk for breast cancer may consider preventive (prophylactic) mastectomy. This is the surgical removal of the breasts before breast cancer is ever diagnosed. Possible candidates include:
Your doctor may do a total mastectomy to reduce your risk of breast cancer. This may reduce, but does not eliminate the risk of breast cancer.
Many risk factors, such as your genes and family history, cannot be controlled. However, eating a healthy diet and making a few lifestyle changes may reduce your overall chance of getting cancer.
There is still little agreement about whether lifestyle changes can prevent breast cancer. The best advice is to eat a well-balanced diet and avoid focusing on one "cancer-fighting" food. The American Cancer Society's dietary guidelines for cancer prevention recommend that people:
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