A pair of hands holding a red cancer ribbon

Breast Cancer

Breast cancer occurs when normal cells in the breast undergo changes in their molecular characteristics, allowing them to grow and multiply uncontrollably. Excluding skin cancers, breast cancer is the most common type of cancer in women, affecting approximately 12% of women over the course of their lifetime.

Breast cancer is described based on the type of breast tissue where the tumor originates. For example, cancers that begin in the breast ducts are called ductal cancers and those in the lobules (glands) are lobular cancers. 

Breast cancer typically does not cause symptoms in the early stages and is often detected with screening mammograms. Treatments depend on the cancer stage and type, and may include surgery, chemotherapy, hormonal therapy, biological therapy, and radiation therapy.

Frequently Asked Questions

  • Can men get breast cancer?

    While breast cancer is rare in men, the disease can affect men too. Men can also have breast lumps and should get a prompt medical evaluation for any lump or change in the appearance of their chest or breast area.

  • Does breast cancer hurt?

    Breast cancer is usually painless during its early stages, but growths can stretch the skin and breast tissue, causing discomfort or pain. The pain can be anywhere in the breast or it may occur in the nipple.

  • How do you check for breast cancer?

    To check for lumps, perform monthly mid-cycle self-checks (about two weeks after your period). Screening mammograms are recommended yearly for women over the age of 45, and sometimes younger for those considered high risk. Doctors may do breast examinations, take a biopsy (sample of breast tissue), or may recommend genetic testing, such as for BRCA gene mutations linked to breast cancer.

  • What are the signs of breast cancer?

    Seek medical attention if you feel or notice a lump in your breast or if you have any breast or nipple pain, swelling in the armpit (lymph nodes), persistent tenderness, an inverted or retracted nipple, or a change in breast size or shape. Additional things to look for are breast discoloration, scaly or pitted skin, and clear or bloody nipple discharge.

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Page Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Cancer Institute. Breast Cancer Risk in American Women. Updated October 3, 2019.

  2. Centers for Disease Control and Prevention. How Is Breast Cancer Treated? Updated September 14, 2020.

  3. American Cancer Society. Frequently Asked Questions About the American Cancer Society’s Breast Cancer Screening Guideline. Updated January 24, 2019.

  4. American Cancer Society. Invasive breast cancer (IDC/ILC). Updated September 20, 2019.

  5. American Cancer Society. What Is Breast Cancer? Updated September 18, 2019.