Breast Imaging

Mammograms

A mammogram is an X-ray of the breast. A screening mammogram is a routine study, done once a year after the age of 40, on a woman who has no breast problems or symptoms. This annual test should be done on younger women if they have a family history of early breast cancer. The breast tissue is compressed (squeezed) from two different directions and pictures are taken that can be evaluated by the radiologist. The breast is checked for changes from last year, new calcium deposits that are grouped in one area of the breast, or new masses or densities. A letter will be sent directly to you from the radiologist notifying you about the results of your screening mammogram. 

A diagnostic mammogram is used when there is a breast complaint or symptom, or when an abnormality has been discovered on a routine screening mammogram. Once someone has been diagnosed and treated for breast cancer, they may also be told to have a diagnostic mammogram annually for the first five years after their diagnosis. A diagnostic mammogram is a series of pictures used to evaluate the area of concern. This may involve pictures with special paddles or magnification to better examine the tissue. It may also require the additional step of performing an ultrasound for a complete evaluation. The radiologist will speak to you directly about the findings and recommendations. A biopsy may be required if there is something still of concern.

Ultrasound

A breast ultrasound is a test that evaluates the breast tissue using sound waves. This is most helpful in determining whether a palpable mass is solid (in which case it could be benign or malignant) or a fluid-filled sac (a benign cyst). As mentioned above, ultrasound can be used to look at questionable areas seen on the mammogram to better determine what it might represent.

An ultrasound is a painless test where you will be comfortably lying on your back, and the technician in will rub a handheld probe covered in gel over your breast. Biopsies frequently can be done under the guidance of breast ultrasound.

Screening breast ultrasound can be a useful backup tool in evaluating dense breast tissue. Dense breast tissue can result in poorer detection of cancers by mammography. In addition, it is now believed that dense breast tissue slightly increases a woman's risk for developing breast cancer. For these reasons, additional imaging studies, such as ultrasound or MRI, may be indicated depending on your particular risk factors. In this case, all areas of both breasts will be evaluated with the sound wave probe. It is important to remember that there are pros and cons of this additional screening test. While ultrasound may detect cancers not found on mammography, it is possible that additional findings may require additional imaging follow-up or biopsy.

MRI (Magnetic Resonance Imaging)

A breast MRI is a very sensitive examination that uses a powerful magnetic field and a computer to take detailed pictures of the breast tissue. A dye called gadolinium is injected into your vein as part of this scan. This test can be used to help detect abnormalities not easily seen with either mammography or ultrasound. You will lie on your stomach on a table, which slides, feet first, inside the magnet. During imaging, it can be noisy so headphones will be placed over your ears. MRI is performed for several reasons. It is often used in patients who present with a lymph node that has cancer but the mammogram and ultrasound are negative. If there is a question of cancer invading the chest wall or an implant rupture, MRI may also be useful. Many surgeons will use MRI to better evaluate the extent of a malignancy to help with surgical planning or to assess the response of a cancer after pre-operative chemotherapy. Breast MRI can also be used for screening in high-risk individuals. 

Appropriate patients for high-risk screening by breast MRI include:
  • Known BRCA mutation carriers or people with a first-degree family history of a BRCA 1-2 gene mutation.
  • Strong family history (lifetime risk of >20-25 percent by BRCAPRO or similar risk assessment model).
  • Prior chest wall radiation given between the ages of 10 to 30 years.
Like ultrasound, there are pros and cons to screening breast MRI, and false positives requiring additional imaging or biopsy are common.