Breast Cancer

Breast cancer is cancer that forms in the cells of the breasts. After skin cancer, breast cancer is the most common cancer diagnosed in women in the United States. It can occur in both men and women, but it's far more common in women.

Substantial support for breast cancer awareness and research funding has helped improve the screening and diagnosis and advances in the treatment of breast cancer. Breast cancer survival rates have increased, and the number of deaths steadily has been declining, which is largely due to a number of factors such as earlier detection, a new personalized approach to treatment and a better understanding of the disease.

Tests and procedures used to diagnose breast cancer include:

  • Breast exam. Your doctor will check both of your breasts and lymph nodes in the armpit, feeling for any lumps or other abnormalities.
  • Mammogram. A mammogram is an X-ray of the breast. Mammograms are commonly used to screen for breast cancer. If an abnormality is detected on a screening mammogram, your doctor may recommend a diagnostic mammogram to further evaluate that abnormality.
  • Breast ultrasound. Ultrasound uses sound waves to produce images of structures deep within the body. Ultrasound may help distinguish between a solid mass and a fluid-filled cyst. An ultrasound is often obtained as part of the examination of a new lump.
  • Removing a sample of breast cells for testing (biopsy). Biopsy samples are sent to a laboratory for analysis where experts determine whether the cells are cancerous. A biopsy sample is also analyzed to determine the type of cells involved in the breast cancer, the aggressiveness (grade) of the cancer, and whether the cancer cells have hormone receptors or other receptors that may influence your treatment options.
  • Breast magnetic resonance imaging (MRI). An MRI machine uses a magnet and radio waves to create pictures of the interior of your breast. Before a breast MRI, you receive an injection of dye.
  • Other tests and procedures may be used depending on your situation.
  • Staging breast cancer
  • Once your doctor has diagnosed your breast cancer, he or she works to establish the extent (stage) of your cancer. Your cancer's stage helps determine your prognosis and the best treatment options.
  • Complete information about your cancer's stage may not be available until after you undergo breast cancer surgery.
  • Tests and procedures used to stage breast cancer may include:
  • Blood tests, such as a complete blood count
  • Mammogram of the other breast to look for signs of cancer
  • Breast MRI
  • Bone scan
  • Computerized tomography (CT) scan
  • Positron emission tomography (PET) scan
  • Not all women will need all of these tests and procedures. Your doctor selects the appropriate tests based on your specific circumstances and taking into account new symptoms you may be experiencing.
  • Breast cancer stages range from 0 to IV with 0 indicating 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.