Breast Density: What You Should Know
One of the important variable characteristics in breast anatomy and physiology is breast tissue density. The density of breast tissue is derived from the ratio of fatty tissue to glandular (dense) tissue and varies greatly from woman to woman and sometimes year to year. The fact that dense breast tissue lowers the accuracy of mammograms has been recognized for some time. However, that reduction in accuracy should in no way serve as a reason for women with dense breast tissue to forgo their annual mammogram. For consistency, the American College of Radiology has four grades of breast composition to describe the breast density of all patients using the following scale below.
Grade 1. The breast is almost entirely fat (less than 25% glandular).
Grade 2. There are scattered fibro glandular densities (approximately 25% - 50% glandular).
Grade 3. The breast tissue is heterogeneously dense, which could obscure detection of small masses (approximately 51% - 75% glandular).
Grade 4. The breast tissue is extremely dense. This may lower the sensitivity of mammography (greater than 75% glandular).
The assignment of a breast density grade by a radiologist when your mammogram is interpreted is often a “subjective” determination and could change from year-to-year with little actual change in density.
For a more extensive discussion on the anatomy and physiology of dense breast tissue, how it can change and how it may affect ones risk for breast cancer, click here.
Other helpful links:
For a more scientific exploration of breast density and its relevance as a possible independent risk factor for breast cancer, please view the articles listed below.
Bassett Healthcare Network has state of the art digital mammography - The advantages of this are that digital mammograms are faster than film mammograms because there is no film to develop. The image can be sent immediately to the radiologist for viewing. If the image is unclear, you will be told about it right away, and the image can be retaken. This may help reduce mammogram callbacks and stress on patients. The National Cancer Institute did a study comparing film and digital mammography, and concluded that digital mammography is more accurate than film at finding cancer in women less than 50 years old, and women who have dense (not fatty) breast tissue. Digital mammography uses less radiation than traditional film mammography, reducing your lifetime exposure to X-rays.
October 2012 marked the 20th anniversary of the Mammography Quality Standards Act (MQSA). This legislation established national standards for accreditation, certification, and inspection of mammography facilities in the U.S. Because of these standards, millions of women who receive mammograms in the U.S. each year can be confident they are receiving high-quality, consistent and reliable breast imaging at mammography facilities across the country.