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LaWanda Crawford, NP

Medically reviewed by:
LaWanda Crawford, NP

Breast cancer is cancer that grows in breast tissue. It occurs when abnormal or cancerous cells in the breasts multiply and form tumors, which may spread from the breast to other parts of the body. Knowing the signs and symptoms of breast cancer and being screened regularly can help you protect your health and receive early treatment if needed.

Breast cancer signs & symptoms

Signs of breast cancer typically vary from one person to the next based on the size and location of the tumor. Many women visit their doctors when they notice or feel a lump inside the breast.

Breast cancer symptoms may include:

  • A mass or lump in the breast
  • Changes in the size, shape, and/or appearance of the breast
  • Changes in the color of the skin on the breast
  • A thickened patch of skin that feels different from the surrounding areas
  • Inverted or flattened nipple
  • Peeling, scaling, crusting, or flaking of the skin on the breast
  • Clear or blood-tinged discharge from the nipple

What causes breast cancer?

Researchers and healthcare professionals do not know exactly what causes breast cancer, but have learned that certain factors may increase your risk.

Risk factors of breast cancer include:

  • Being female
  • Having a personal or family history of breast cancer
  • Having a personal history of other breast-related conditions
  • Getting your first period before the age of 12
  • Starting menopause after the age of 55
  • Having dense breast tissue
  • Having your first child after the age of 30
  • Never having been pregnant
  • Inherited DNA changes linked to breast cancer
  • Alcohol use
  • Smoking
  • Obesity
  • Exposure to radiation
  • Menopausal hormone therapy

Types of breast cancer

There are several types of breast cancer, each of which is classified based on factors such as cell type and hormonal behavior.

Type Description
Invasive ductal carcinoma (IDC) IDC starts in the milk ducts and spreads to nearby breast tissue. It is the most common type of breast cancer in the U.S.
Invasive lobular breast cancer This type of cancer originates in the lobules, which are the milk-producing glands in the breast. It often spreads to nearby breast tissue and is the second most common breast cancer in the U.S.
Ductal carcinoma in situ (DCIS) A non-invasive type of breast cancer in which cancer cells form and stay in the breast duct.
HER2-positive breast cancer This cancer is any invasive breast cancer that produces high amounts of extra HER2 protein—a protein that promotes cell growth.
Triple-negative breast cancer (TNBC) Esta forma poco común de cáncer de seno afecta la piel del pezón y puede parecer sarpullido.
Inflammatory breast cancer (IBC) IBC resembles a rash on the breast and is one of the rarest forms of breast cancer.
Paget’s disease of the breast This rare form of breast cancer affects the skin on the nipple and may resemble a rash.

Breast cancer screening

Breast cancer screening can detect breast cancer early on, when it is easy to treat. The U.S. Preventive Services Task Force recommends breast cancer screenings every two years for women between the ages of 40 and 74.

Contact your primary care provider to make an appointment for breast cancer screenings or to find out when you should have your next mammogram. Screenings are usually available at clinics, hospitals, and doctors’ offices.

If you think you may have breast cancer, your provider may review your medical history, talk to you about your symptoms, and perform a physical exam. Your provider may also order tests to diagnose the cancer or refer you to an oncologist or radiologist who specializes in diagnosing breast cancer and breast cancer treatment.

Diagnostic tests for breast cancer include:

  • Mammogram
  • Breast ultrasound
  • MRI
  • Breast biopsy
  • Immunohistochemistry test, to check for hormone receptors such as HER2
  • Genetic testing to identify DNA mutations linked to breast cancer

Frequently asked questions about breast cancer

Can men get breast cancer?

Anyone with breast tissue can get breast cancer. Therefore, men can get breast cancer. The prevalence of male breast cancer is 1%.

DCIS and IDC are the most common types of breast cancer in men. Men have the same breast cancer symptoms and risk factors as women, though liver disease and Klinefelter syndrome are additional risk factors for men. Klinefelter syndrome is a rare genetic condition in which a male has an extra X chromosome that increases the production of estrogen while lowering the production of androgens.

Is breast cancer genetic?

Yes, breast cancer is thought to be genetic in 5% to 10% of cases. You may be at high risk if you have an inherited mutation in the BRCA1 or BRCA2 genes. BRCA1 and BRCA2 produce proteins that repair damaged DNA; however, mutations in these genes can lead to abnormal cell growth, which promotes cancer.

BRCA1 and BRCA2 mutations are responsible for the majority of genetic breast cancer cases. Genetic testing can be performed to identify whether you have inherited mutations in these genes or in others, such as ATM and PALB2, that are commonly implicated in breast cancer.

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