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College of Radiology and the Society of Breast Imaging in making recommendations to reverse the trend.
Other factors that might prevent women from undergoing screening mammography include intolerance of the discomfort associated with the screening test, fear of what could be found, disabilities that make screening facilities inaccessible, language and cultural barriers for immigrant women, and inconvenience due to a lack of nearby screening facilities. A lack of education as to the benefits of undergoing mammograms on a regular basis can also be an impediment to such screening.
Lessons learned from the adoption and dissemination of mammography may be useful as new technologies become available. However, because mammography filled a breast cancer detection void, the adoption process for new technologies is likely to be quite different. New breast cancer detection technologies will not be adopted unless they can provide added value to technologies currently in use. If they can, then such new technologies might enable breast cancer detection to be more tailored to an individual woman's needs. For example, MRI might be used to screen young women who have a high risk of developing breast cancer and also have dense breast tissue that makes it difficult to interpret x-ray mammograms. However, the adoption of such new technologies will also make developing guidelines for breast cancer screening and diagnosis more complex.
SUMMARY
The committee determined that an ideal screening tool for breast cancer detection should be:
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linked to low health risks stemming from its use;
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sensitive enough to detect nearly all breast cancers, yet specific enough to rarely falsely indicate the presence of tumors;
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able to detect breast cancer at a curable stage;
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able to distinguish life-threatening abnormalities from those not likely to cause harm;
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non-invasive and simple to perform;
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easy to interpret objectively and consistently; and
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cost-effective, widely available and acceptable to women.
The ideal breast cancer screening tool has not yet been developed. Conventional x-ray mammography is the current mainstay for early breast cancer detection, and has been proven to reduce the number of women dying
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from the disease. However, it has a number of limitations, including fostering overtreatment of some breast abnormalities likely to be harmless, and an inability to detect all breast cancers in all types of breast tissue (that is, in dense or scarred tissue). A number of technical improvements have been made to x-ray mammography, but studies have not been undertaken to determine whether these changes have reduced the number of deaths from breast cancer.
Researchers are also developing additional imaging tools and other means for detecting breast cancers. These new technologies have the potential for improving breast cancer screening and diagnosis, but it appears that no major steps forward have yet been taken in this area. All of the technologies being developed for breast cancer detection have different strengths and limitations. Many of these new technologies may first be introduced as additions to mammography to improve its accuracy and reduce the number of unnecessary biopsies.
The pathway from the development of new techniques for detecting breast cancer to their mainstream use in clinics is long, arduous, and costly. Also, the end results of such research and development are unpredictable, making it a financially risky undertaking. A number of challenges must be met along this development pathway. Researchers must secure access to research resources and funding, meet the standards for FDA regulation and insurance coverage (including conducting expensive clinical trials to show that a new device is effective), and gain the acceptance of patients and their health care providers.
After studying these issues in depth, the IOM committee has made a number of recommendations that aim to improve the development and adoption process for new technologies. They have also put forth a series of recommendations that aim to make the most of the technologies currently available for breast cancer detection, as described in this report.
The committee cautioned that we should temper our eagerness to embrace new technologies by keeping in mind the ultimate goal: to reduce the toll of breast cancer in our society. Technologies that enable detection of breast abnormalities at an even earlier stage than what is currently possible may or may not meet that goal. It is essential to understand what is being detected and how to intervene appropriately. Concerted efforts to improve our understanding of the biology of breast cancer, coupled with improved technologies for screening and diagnosis, could help overcome some of the present limitations of breast cancer detection, ultimately reducing the burden of breast cancer in this country.
