How is breast cancer diagnosed?

If you have a symptom or screening test result that suggests cancer, your doctor must find out whether it is due to cancer or to some other cause. Your doctor may ask about your personal and family medical history. You may have a physical exam. Your doctor also may order a mammogram or other imaging procedure. These tests make pictures of tissues inside the breast. After the tests, your doctor may decide no other exams are needed. Your doctor may suggest that you have a follow-up exam later on. Or you may need to have a biopsy to look for cancer cells.

Clinical breast exam

Your health care provider feels each breast for lumps and looks for other problems. If you have a lump, your doctor will feel its size, shape, and texture. Your doctor will also check to see if it moves easily. Benign lumps often feel different from cancerous ones. Lumps that are soft, smooth, round, and movable are likely to be benign. A hard, oddly shaped lump that feels firmly attached within the breast is more likely to be cancer.

Diagnostic mammogram

Diagnostic mammograms are x-ray pictures of the breast. They take clearer, more detailed images of areas that look abnormal on a screening mammogram. Doctors use them to learn more about unusual breast changes, such as a lump, pain, thickening, nipple discharge, or change in breast size or shape. Diagnostic mammograms may focus on a specific area of the breast. They may involve special techniques and more views than screening mammograms.

Ultrasound

An ultrasound device sends out sound waves that people cannot hear. The waves bounce off tissues. A computer uses the echoes to create a picture. Your doctor can view these pictures on a monitor. The pictures may show whether a lump is solid or filled with fluid. A cyst is a fluid-filled sac. Cysts are not cancer. But a solid mass may be cancer. After the test, your doctor can store the pictures on video or print them out. This exam may be used along with a mammogram.

Magnetic resonance imaging

Magnetic resonance imaging(MRI) uses a powerful magnet linked to a computer. MRI makes detailed pictures of breast tissue. Your doctor can view these pictures on a monitor or print them on film. MRI may be used along with a mammogram.

Biopsy

Your doctor may refer you to a surgeon or breast disease specialist for a biopsy. Fluid or tissue is removed from your breast to help find out if there is cancer.

Some suspicious areas can be seen on a mammogram but cannot be felt during a clinical breast exam. Doctors can use imaging procedures to help see the area and remove tissue. Such procedures include ultrasound-guided, needle-localized, or stereotactic biopsy.

Doctors can remove tissue from the breast in different ways:

• Fine-needle aspiration: Your doctor uses a thin needle to remove fluid from a breast lump. If the fluid appears to contain cells, a pathologist at a lab checks them for cancer with a microscope. If the fluid is clear, it may not need to be checked by a lab.
  
• Core biopsy: Your doctor uses a thick needle to remove breast tissue. A pathologist checks for cancer cells. This procedure is also called a needle biopsy.
  
• Surgical biopsy: Your surgeon removes a sample of tissue. A pathologist checks the tissue for cancer cells.
  
• An incisional biopsy takes a sample of a lump or abnormal area.
  
• An excisional biopsy takes the entire lump or area.
  

If cancer cells are found, the pathologist can tell what kind of cancer it is. The most common type of breast cancer is ductal carcinoma. Abnormal cells are found in the lining of the ducts. Lobular carcinoma is another type. Abnormal cells are found in the lobules.

If you are diagnosed with cancer, your doctor may order special lab tests on the breast tissue that was removed. These tests help your doctor learn more about the cancer and plan treatment:

• Hormone receptor test: This test shows whether the tissue has certain hormone receptors. Tissue with these receptors needs hormones (estrogen or progesterone) to grow.
  
• HER2 test: This test shows whether the tissue has a protein called human epidermal growth factor receptor-2 (HER2) or the HER2/neu gene. Having too much protein or too many copies of the gene in the tissue may increase the chance that the breast cancer will come back after treatment.