Beyond Mammograms: More Types of Breast Cancer Tests

By Dianne Lange. Medically reviewed by Tom Iarocci, MD. May 7th 2016

For 40 years, traditional mammograms, the use of X-rays to create an image of the breast on film, has been the gold standard for breast cancer screenings and early detection of breast cancer.

"It's the only test that has been proven to reduce the rate of death. And it's the least expensive," says Jennifer Drukteinis, M.D., assistant professor of radiology at the H. Lee Moffitt Cancer Center in Tampa, Fla.

Yet as effective as a mammogram is for saving lives, it isn’t foolproof. Its sensitivity — that is, how well a mammogram reveals breast cancer on film — is 98 percent effective for women with fatty breasts but only 36 percent effective for those with dense breasts.

One reason for the discrepancy is that dense breast tissue looks white in mammograms, and non-dense breast tissue is fatty and appears grayish on film. Plus, false positive results — a spot on the mammogram that looks like cancer but isn't — continue to be a problem, leading to unnecessary biopsies.

However, major advances are making the breast cancer testing process more effective. One of them, digital mammography, creates a digital image of the breast that can be enlarged, rotated and brightened for closer scrutiny. It gives radiologists an edge at spotting abnormalities, especially in premenopausal women and older women with dense breasts. Most centers are replacing film mammograms with digital imaging systems.


Additional breast cancer screening tests

While mammography remains the best test for routine screening, there are two other imaging tests that can be used along with it: an MRI and ultrasound. And two imaging techniques are better than one in certain situations like these:

  • When your breast density is an issue;
  • When you need to zero in on something that looks suspicious on a mammogram;
  • When nothing abnormal appears on a mammogram but you feel a lump; or
  • When the odds of cancer are very high.


1.      MRI

An MRI, or magnetic resonance imaging, uses magnetic and radio waves to create a detailed 3-D image. An MRI can detect a small, invasive cancer not seen on a mammogram.


Who it helps:

  • Women with abnormal mammograms and those already diagnosed with breast cancer;
  • Patients with other malignancies or a cancer recurrence;
  • Women who have received radiation therapy to the chest; and
  • Young women at higher risk for breast cancer.


What you need to know:

An MRI has a higher false positive rate than mammography and is more costly. It may not be useful for women with very large breasts, and may not detect ductal carcinoma in situ (DCIS), or tiny calcifications that can signal cancer. Some consider the presence of DCIS an early stage of breast cancer.


2.      Ultrasound

Also known as a sonogram, this technique converts the echoes of sound waves bouncing off of tissues into a digital image.


Who it helps:

  • Women with denser breasts;
  • Young women with lumpy breasts; and
  • Women with suspicious lumps that may be fluid-filled cysts.


What you need to know:

The accuracy of the test depends on the skill of the lab technician running the transducer (the main probe used in an ultrasound machine) across your breast. It gives many false results, both positive and negative.


New cancer tests on the block

The U.S. Food and Drug Administration has approved two new test as adjuncts to mammography. You may not have heard about these new breast cancer screening tests yet, but they’re becoming more widely available.


1.      Tomosynthesis

Also known as 3-D mammography, this test involves a rotating X-ray tube that takes multiple 2-D images of the breast and converts these digital "slices" of the breast into a single, detailed 3-D image similar to that of a CT scan.


Who it helps:

  • Women with dense breast tissue; and
  • Women who have an increased risk of breast cancer.

What you need to know:

Tomosynthesis exposes you to roughly 8 percent more radiation than mammography. However, false positive results are less likely, especially for women with dense breasts and those younger than age 50.


2.      Automated Whole Breast Ultrasound (AWBUS)

Think of an AWBUS machine as an ultrasound robot: A technician must hold the ultrasound transducer on the breast, but a computer-driven arm adjusts the pressure and direction it takes over a customized nipple pad that covers the entire breast. "It takes human skill and error out of the equation," says Drukteinis.


Who it helps:

  • Women with dense breast tissue whose mammography results were benign.


What you need to know:

Although a study done by one manufacturer found that AWBUS detected lesions not apparent on a mammogram, another small but independent study found that when AWBUS and traditional sonography were done by an experienced radiologist, there was no difference in breast cancer detection.


Take the Next Steps

Know your risks. What tests you have, when you have them and how often depends on your individual risk of developing breast cancer. Developed by the National Cancer Institute and National Surgical Adjuvant Breast and Bowel Project, the Breast Cancer Risk Assessment Tool can help you ascertain your risk. Additionally, you can:

  1. Talk to the experts. The American Cancer Society recommends that women at higher risk of breast cancer have an MRI and a mammogram every year. In fact, those at moderately increased risk (a 15 to 20 percent lifetime risk) should talk with their doctors about having an MRI.
  2. Ask about breast density. Several states require that the radiologist inform you of your breast density when you get your mammogram results. If you don’t know, ask; dense breasts can increase your risk four to six times.
  3. Head to the proper place. Not all equipment is the same. If you need an MRI, be sure the facility uses a breast MRI machine. To avoid having the test twice, ask if an MRI-guided breast biopsy can be done if needed.
  4. Go digital. "If I were going for my first mammogram, I would certainly go to a center that offers digital mammography," Drukteinis emphasizes.

More in category

Related Content