Breast cancer is cancer that forms in the cells of the breasts. There are numerous types of breast cancer, but cancer that begins in the milk ducts (ductal carcinoma) is the most common type.
After skin cancer, breast cancer is the most common cancer diagnosed in women in the United States. Breast cancer can occur in both men and women, but it's far more common in women.
Public support for breast cancer awareness and research funding has helped improve the diagnosis and treatment of breast cancer. Breast cancer survival rates have increased and the number of deaths has been declining, thanks to a number of factors such as earlier detection, new treatments and a better understanding of the disease.
Each of your breasts contains 15 to 20 lobes of glandular tissue, arranged like the petals of a daisy. The lobes are further divided into smaller lobules that produce milk during pregnancy and breast-...
Signs and symptoms of breast cancer may include:
When to see a doctor
Breast and nipple changes can be a sign of breast cancer. Make an appointment with your doctor if you notice anything unusual. ...
It's not clear what causes breast cancer. Doctors know that breast cancer occurs when some breast cells begin growing abnormally. These cells divide more rapidly than healthy cells do. The accumulating cells form a tumor that may spread (metastasize) through your breast, to your lymph nodes or to other parts of your body.
Breast cancer most often begins with cells in the milk-producing ducts. Doctors call this type of breast cancer invasive ductal carcinoma. Breast cancer may also begin in the milk glands known as lobules (invasive lobular carcinoma) within the breast.
Researchers have identified things that can increase your risk of breast cancer. But it's not clear why some people who have no risk factors develop cancer, yet other people with risk factors never do. It's likely that breast cancer is caused by a complex interaction of your genetic makeup and your environment.
Inherited breast cancer
If you have a strong family history of breast cancer or other cancers, blood tests may help identify defective BRCA or other genes that are being passed through your family. Consider asking your doctor for a referral to a genetic counselor, who can review your family health history. A genetic counselor can also discuss the benefits, risks and limitations of genetic testing with you. It's important to remember that the genetic tests help to identify a high-risk individual or family, but they don't definitively predict who will or will not get breast cancer.
How cancer develops
Cancer begins as a cluster of normal cells (hyperplasia). Over time, the cells can develop abnormalities (atypical hyperplasia) that make them different from normal cells, but not yet cancerous. The ...
A risk factor is anything that makes it more likely you'll get a particular disease. But having one or even several risk factors doesn't necessarily mean you'll develop cancer — many women who develop breast cancer have no known risk factors other than simply being women.
Factors that are associated with an increased risk of breast cancer include:
Other risk factors that have been suggested, but don't play any role in the development of breast cancer include tightfitting bras, antiperspirants, breast implants and shift work.
Preparing for your appointment
Consulting with your health care team
What you can do to prepare
Questions to ask your doctor
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask additional questions that may occur to you during your appointment.
Tests and diagnosis
Diagnosing breast cancer
Other tests and procedures may be used depending on your situation.
Staging breast cancer
Tests and procedures used to stage breast cancer may include:
Not all women will need all of these tests and procedures. Your doctor selects the appropriate tests based on your specific circumstances.
Breast cancer stages range from 0 to IV, with 0 indicating cancer that is very small and noninvasive. Stage IV breast cancer, also called metastatic breast cancer, indicates cancer that has spread to other areas of the body.
Calcifications are small calcium deposits in the breast that show up as white spots on a mammogram. Large, round, well-defined calcifications (left column) are more likely to be noncancerous (benign)....
Core needle biopsy
A core needle biopsy uses a long, hollow tube to extract a core of tissue. Here, a biopsy of a suspicious breast lump is being done. The core is sent to a laboratory for testing. ...
Treatments and drugs
Your doctor determines your breast cancer treatment options based on your type of breast cancer, its stage, whether the cancer cells are sensitive to hormones, your overall health and your own preferences. Most women undergo surgery for breast cancer and also receive additional treatment, such as chemotherapy, hormone therapy or radiation.
There are many options for breast cancer treatment, and you may feel overwhelmed as you make complex decisions about your treatment. Consider seeking a second opinion from a breast specialist in a breast center or clinic. Talk to other women who have faced the same decision.
Breast cancer surgery
Complications of breast cancer surgery depend on the procedures you choose. Surgery carries a risk of bleeding and infection.
Some women choose to have breast reconstruction after surgery. Discuss your options and preferences with your surgeon. Consider a referral to a plastic surgeon before your breast cancer surgery. Your options may include reconstruction with a synthetic breast implant or reconstruction using your own tissue. These operations can be performed at the time of your mastectomy or at a later date.
External beam radiation is commonly used after lumpectomy for early-stage breast cancer. Doctors may also recommend radiation therapy after mastectomy for larger breast cancers. When external beam radiation is used after a woman has tested negative on a sentinel node biopsy, there is evidence that the chance of cancer occurring in other lymph nodes is significantly reduced.
Side effects of radiation therapy include fatigue and a red, sunburn-like rash where the radiation is aimed. Breast tissue may also appear swollen or more firm. Rarely, more-serious problems may occur, including arm swelling (lymphedema), broken ribs, and damage to the lungs or nerves.
Chemotherapy is sometimes given before surgery in women with larger breast tumors. Doctors call this neoadjuvant chemotherapy. The goal is to shrink a tumor to a size that makes it easier to remove with surgery. This may also increase the chance of a cure. Research is ongoing into neoadjuvant chemotherapy to determine who may benefit from this treatment.
Chemotherapy is also used in women whose cancer has already spread to other parts of the body. Chemotherapy may be recommended to try to control the cancer and decrease any symptoms the cancer is causing.
Chemotherapy side effects depend on the drugs you receive. Common side effects include hair loss, nausea, vomiting, fatigue and a small increased risk of developing infection.
Hormone therapy can be used after surgery or other treatments to decrease the chance of your cancer returning. If the cancer has already spread, hormone therapy may shrink and control it.
Treatments that can be used in hormone therapy include:
Side effects of targeted drugs depend on the drug you receive. Targeted drugs can be very expensive and aren't always covered by health insurance.
Examples of treatments being studied in breast cancer clinical trials include:
During a lumpectomy, your surgeon makes an incision large enough to remove the tumor and a margin of healthy tissue surrounding the tumor. The rest of your breast remains intact. ...
Simple mastectomy and modified radical mastectomy
A simple, or total, mastectomy (left) removes the breast tissue, nipple, areola and skin, but not all the lymph nodes. A modified radical mastectomy (right) removes the entire breast, including ...
Sentinel node biopsy
To determine whether cancer has spread to the nearby lymph nodes, doctors may use a sentinel node biopsy. Doctors determine which lymph node is likely to be the first stop for spreading cancer ...
External beam radiation uses high-powered beams to kill cancer cells. Beams of radiation are precisely aimed at the breast cancer using a machine that moves around your body. ...
There are no alternative medicine treatments that have been found to cure breast cancer. What's more, some alternative medicine may cause adverse reactions with standard treatments, or might cause you to delay getting treatments that have been proven effective. If you're considering any type of alternative therapy, be sure to discuss the pros and cons with your doctor.
But complementary and alternative medicine therapies may help you cope with side effects of treatment when combined with your doctor's care.
Alternative medicine for fatigue
Coping and support
A breast cancer diagnosis can be overwhelming. And just when you're trying to cope with the shock and the fears about your future, you're asked to make important decisions about your treatment.
Every woman finds her own way of coping with a breast cancer diagnosis. Until you find what works for you, it might help to:
Breast cancer prevention for women with an average risk
Breast cancer prevention for women with a high risk
Catch cancer early
To perform a breast self-exam, use a circling, massaging motion with your fingers. A breast self-exam can help you become familiar with the normal changes in your breasts. ...
Last Updated: 2011-05-07
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