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Diagnosis Cancer

Breast Cancer

If cancer is found in your breast, your doctor will assess the stage or extent of the disease. Staging is an effort to determine if the cancer has spread and, if so, to what parts of the body. Your doctor may use blood and imaging tests to learn the stage of the disease. Treatment decisions depend on these findings. Read Basic Facts about Breast Health to learn more about the staging system.

The first step is usually a physical exam by a doctor or nurse practitioner. Mammography and ultrasound may be part of the exam. On the basis of these evaluations, the decision may be made to perform a tissue biopsy.


Imaging is used to diagnose breast cancer and to evaluate the stage and extent of disease. Three types of imaging are used — mammography, ultrasonography and breast magnetic resonance imaging (MRI). Based on these exams, your doctor may recommend further tests or therapy, or determine that not treatment is necessary.

  • Screening Mammography A mammogram is a low-dose X-ray of the breast. This is the best test to screen for breast cancer. A screening mammogram consists of two "pictures" of each breast. If an area on the mammogram looks suspicious or is not clear, additional mammograms with different views may be needed. Annual screening mammography is recommended for all women over 40 years old.
  • Diagnostic Mammography This is a mammogram used for problem-solving, rather than for screening. For instance, if a patient has a lump in her breast, a directed investigation of that area is performed. This is also done when a particular finding in the breast is being followed over time. A diagnostic mammogram is tailored to the patient's case and is carefully monitored by a radiologist, who interprets the images and determines whether there is any need for further tests.
  • Ultrasonography Using high-frequency sound waves, ultrasonagraphy can often show whether a lump is solid or filled with fluid. This exam may be used along with diagnostic mammography or MRI to answer questions about a specific area of the breast. Because it uses sound waves instead of X-rays, ultrasound provides information that is different and often complementary to the mammogram.
  • Breast MRI Magnetic resonance imaging (MRI) can be used to look specifically at the breast. Each exam produces hundreds of images of the breast, cross-sectional in all three directions (side-to-side, top-to-bottom, front-to-back), which are then read by a radiologist. It can show lesions not visible through mammography or ultrasound. The American Cancer Society recommends that certain women with an especially high risk of developing breast cancer have an MRI scan along with their yearly mammogram. Breast MRI is non-invasive and no radioactivity is involved. The technique is believed to have no health hazards in general.The hope is that such non-invasive studies will contribute to our progress in learning how to predict the behavior of tumors, and in selecting proper treatments. Breast MRI is an evolving technology and should not replace standard screening and diagnostic procedures, such as clinical and self-exams, mammograms, fine needle aspiration or biopsy.


One way to find out if a breast lump or abnormal tissue is cancer is by having a biopsy. During a biopsy, a surgeon, a pathologist or a radiologist removes a portion or all of the suspicious tissue. The suspicious tissue is examined under a microscope by a pathologist who checks for cancer cells and makes the diagnosis. The following are descriptions of different types of biopsies.

  • Fine Needle Aspiration (FNA) Biopsy FNA samples a woman's lump using a thin small needle that leaves a mark no bigger than a needle stick from a blood test. FNA often allows us to diagnose a lump within two to three days.
  • Stereotactic Core Biopsy This procedure was developed as a less invasive way to obtain tissue samples for diagnosis. It involves removing tissue with a biopsy needle while your breast is compressed in a way similar to a mammogram. This biopsy requires less recovery time than surgery and causes no significant scarring. You and your physician and radiologist may consider this procedure if there is an abnormality on a mammogram that cannot be felt. Your radiologist decides if this procedure is technically possible for your condition and your physician decides if it's appropriate for your situation.
  • Needle (Wire) Localization Biopsy This type of biopsy involves the use of a needle and wire to locate the abnormal tissue and surgery to remove it. Needle localization is performed when you have an abnormality on a mammogram that cannot be felt. It is an outpatient biopsy that is done in two steps on the same day.

Decision-making consultation

If you are diagnosed with breast cancer, Collaborative Care services at the UCSF Carol Franc Buck Breast Care Center can help you effectively communicate with your doctors as you navigate the series of complex decisions surrounding your treatment options. To learn more, please read about our Patient Support Corps.

UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.