• image.alt
  • With Mayo Clinic internist

    Sandhya Pruthi, M.D.

    read biography

Mayo Clinic Health Manager

Get free personalized health guidance for you and your family.

Get Started

Free

E-Newsletter

Subscribe to receive the latest updates on health topics. About our newsletters

  • Housecall
  • Alzheimer's caregiving
  • Living with cancer

Question

Mammogram: Can it find cancer in dense breasts?

I've read that a mammogram is useless when it comes to detecting cancer in women with dense breasts. Is this true?

Answer

from Sandhya Pruthi, M.D.

Dense breasts can make traditional mammograms more difficult to interpret. But this doesn't mean a traditional mammogram is useless for detecting cancer or other breast abnormalities in women with dense breasts.

Breast tissue is composed of fatty (nondense) tissue and connective (dense) tissue. The relative ratio of fatty tissue to connective tissue differs among women. As women age, their breasts tend to become less dense.

Dense breast tissue appears as a solid white area on a mammogram film, and fat appears as a dark area. Mammogram X-rays do not penetrate — or "see through" — dense tissues as well as they do through fat. So, in women with dense breasts, mammograms are more difficult to interpret. Tumors also are dense tissue and appear as solid white areas on the mammogram. This can make it more difficult to detect a tumor in dense breasts because it looks a lot like the dense tissue that surrounds it. It's not clear why some women have denser breast tissue than do others.

Some studies have found that newer digital mammography does a better job detecting cancer in dense breasts than does traditional mammography. A digital mammogram produces images on a computer screen that can be enhanced and magnified for closer viewing. However, digital mammograms aren't as widely available as are traditional mammograms. Also, some insurance companies won't pay for the more expensive digital mammograms.

Make an appointment with your doctor if you notice any worrisome breast signs or symptoms, such as a lump or nipple discharge, even if a recent mammogram was normal. Your doctor may recommend other imaging tests, such as a breast ultrasound, to further investigate a breast abnormality.

Next question
Breast implants: Do they interfere with mammograms?
References
  1. Pisano ED, et al. Diagnostic performance of digital versus film mammography for breast-cancer screening. The New England Journal of Medicine. 2005;353:1773.
  2. Mammograms. National Cancer Institute. http://www.cancer.gov/cancertopics/factsheet/Detection/screening-mammograms. Accessed Sept. 14, 2009.
  3. Mammography. RadiologyInfo. http://www.radiologyinfo.org/en/info.cfm?PG=mammo. Accessed Sept. 17, 2009.
  4. Berg WA. Tailored supplemental screening for breast cancer: What now and what next? American Journal of Roentgenology. 2009;192:390.
  5. Mammography. Susan G. Komen Foundation. http://ww5.komen.org/BreastCancer/Mammography.html. Accessed Sept. 17, 2009.
  6. Pisano ED, et al. Diagnostic accuracy of digital versus film mammography: Exploratory analysis of selected population subgroups in DMIST. Radiology. 2008;246:376.
  7. Venkataraman S. Breast imaging: Mammography and ultrasonography. http://www.uptodate.com/home/index.html. Accessed Sept. 17, 2009.
  8. Pruthi S (expert opinion). Mayo Clinic, Rochester, Minn. Sept. 24, 2009.

AN01137

Nov. 3, 2009

© 1998-2009 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "EmbodyHealth," "Reliable tools for healthier lives," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.

Print Share Reprints

Text Size: smaller largerlarger