Female Breast Cancer

Breast cancer will affect 1 in 8 women during their lives. Breast self-examination and routine screening can help find and treat breast cancer in its early, most treatable stages.

Female Breast Cancer Overview

Reviewed: July 14, 2014

Breast cancer is cancer that forms in the cells of the breast. It is the most common cancer diagnosed in women in the United States.

Most lumps found in the breast are not cancer. They are usually caused by fibrosis or cysts.


Surgery, radiation therapy, chemotherapy, and hormone therapy are often used to treat breast cancer.


Female Breast Cancer Symptoms

Signs and symptoms of breast cancer may include:

  • Bloody discharge from the nipple
  • Change in the size, shape or appearance of a breast
  • Changes to the skin over the breast, such as dimpling
  • A newly inverted nipple

Female Breast Cancer Causes

The cause of breast cancer is not entirely clear. Cancer occurs when some breast cells begin growing abnormally. These cells divide more rapidly than healthy cells do and continue to accumulate, forming a lump or mass. The cells may spread (metastasize) through your breast to your lymph nodes or to other parts of your body.


Hormonal, lifestyle, and environmental factors may increase the risk of getting breast cancer, but it is not clear why some people who have no risk factors develop cancer and other people with risk factors never do. Breast cancer is likely caused by a complex interaction of genetic makeup and environment. An estimated 5 to 10 percent of breast cancers are linked to gene mutations passed through generations of a family, but there are several inherited mutated genes that can increase the likelihood of breast cancer. The most common are breast cancer gene 1 (BRCA1) and breast cancer gene 2 (BRCA2), both of which significantly increase the risk of both breast and ovarian cancer.

Other factors that are associated with an increased risk of breast cancer include:

  • A personal history of breast cancer. If you have had breast cancer in one breast, you have an increased risk of developing cancer in the other breast.
  • A family history of breast cancer. If your mother, sister, or daughter was diagnosed with breast cancer, particularly at a young age, your risk of breast cancer is increased.
  • Obesity. Being obese increases your risk of breast cancer.

Female Breast Cancer Diagnosis

Tests and procedures used to screen for and diagnose breast cancer include:

  • Breast exam. Your doctor will feel both of the breasts and lymph nodes in the armpit, feeling for any lumps or other abnormalities.

Once your doctor has diagnosed your breast cancer, he or she works to establish the extent (stage) of your cancer by conducting tests such as blood tests, additional mammograms, magnetic resonance imaging of the breast, computerized tomography scan, and positron emission tomography. The cancer's stage helps determine your prognosis and the best treatment options. Breast cancer stages range from 0 to IV. Stage 0 indicates cancer that is noninvasive or contained within the milk ducts. Stage IV breast cancer, also called metastatic breast cancer, indicates cancer that has spread to other areas of the body.

Living With Female Breast Cancer

If you have or have had breast cancer, you can take steps to manage the stress that accompanies the diagnosis:

  • Learn about breast cancer so you can make informed decisions about your care.
  • Accept help and support from family and friends.
  • Talk with other cancer survivors or attend support groups.

Female Breast Cancer Treatments

The treatments for breast cancer are based on the type of cancer, the stage of the cancer, whether the cancer is sensitive to hormones, your overall health, and your preferences. Most women undergo surgery for breast cancer and also receive additional treatment before or after surgery, such as chemotherapy, hormone therapy, targeted drug therapy, or radiation.

Surgeries used to treat breast cancer may involve removing just the cancer (lumpectomy), removing the entire breast (mastectomy), and removing lymph nodes involved in the cancer (sentinel node biopsy or axillary lymph node dissection).


Chemotherapy uses drugs to destroy cancer cells. If your cancer has a high risk of returning or spreading to another part of your body, your doctor may recommend chemotherapy to decrease the chance that the cancer will recur. Chemotherapy is sometimes given before surgery in women with larger breast tumors. The goal is to shrink a tumor to a size that makes it easier to remove with surgery. 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.

Common chemotherapy drugs used in breast cancer include:



Treatments that can be used in hormone therapy include:

  • Selective estrogen receptor modulator (SERM) medications, which block estrogen from attaching to the estrogen receptor on the cancer cells and slow the growth of tumors and killing tumor cells. SERMs include tamoxifen, raloxifene (Evista) and toremifene (Fareston).
  • Aromatase inhibitors, which block the action of an enzyme that converts androgens (male sex hormones) in the body into estrogen (female sex hormones). These drugs are effective only in postmenopausal women. Aromatase inhibitors include anastrozole (Arimidex), letrozole (Femara) and exemestane (Aromasin).
  • Fulvestrant (Faslodex) blocks estrogen receptors on cancer cells and signals the cell to destroy the receptors. Fulvestrant is used in postmenopausal women.
  • Targeted drug treatments attack specific abnormalities such as protein growth within cancer cells. Targeted drugs used to treat breast cancer include: ado-trastuzumab (Kadcyla), Bevacizumab (Avastin), lapatinib (Tykerb), pertuzumab (Perjeta), and trastuzumab (Herceptin).