Mammography has helped lower the death rate from breast cancer, but a new report by the Institute of Medicine says much could be done to improve breast cancer screening and save even more lives.
Increasing the number of women who get mammograms and making the tests more accurate should be top priorities, the report said.
The American Cancer Society and many other organizations recommend that most women begin getting annual mammograms at age 40. But many women fail to get screened, or to be screened regularly, the IOM report noted. In some cases, these women lack health insurance, while in others they choose not to be screened because they fear the disease or even the mammogram itself. The lack of reminder systems is a major factor in irregular screening.
But in many cases, the report said, women simply lack adequate access to screening facilities and doctors. Fewer radiologists are specializing in mammography and screening facilities across the country are closing; this combination has led to wait times of up to 5 months for a mammogram in some parts of the US, the report said.
Improve Interpretation of Mammograms
Another problem is the accuracy of mammograms. Although the best screening method currently available, mammograms still miss up to 17% of tumors and return a false-positive result (wrongly identifying a benign condition as cancer) 1 time out of 10. Reducing that number could save up to $100 million every year, the report said.
To do that, the report recommends taking a cue from European screening programs. The US could adopt national certification standards for radiologists, as is done in Britain. Or mammograms could all be sent to a handful of specialized centers where highly trained specialists would examine them for abnormalities; this technique has helped cut down on the rate of false-positive readings in Sweden and the Netherlands.
The idea has merit, and newer technologies like digital mammography may contribute to making it feasible, said Robert Smith, PhD, director of screening at the American Cancer Society.
In areas where there may be a shortage of radiologists, for instance, digital mammography units could be used to capture images of the breast, which would then be transferred electronically to a specialized center elsewhere for interpretation by experts.
"Training, experience, high volume, and regular feedback result in interpreting physicians who do a better job at finding small cancers," Smith said, "so we should do whatever it takes to have mammograms read by people who are specialists and who really like to do it."
The report also suggests creating a new type of health care specialist who is not a doctor, but who is trained to read mammograms. These specialists would help radiologists interpret mammograms, so that each x-ray would be examined by two people instead of just one.
Although it would be possible to train people who aren't doctors to read mammograms effectively, Smith said the threat of malpractice litigation poses a huge obstacle for the supervising physician. But, he added, with more than 1 million new women entering the screening age range each year, "we may need to do something quite extraordinary to make sure that access to screening doesn't become a major problem."
New Screening Technologies Needed
New screening technologies will also be important to reducing the death rate from breast cancer, the report said. It called for greater collaboration among researchers, funding agencies, insurers, and doctors so that new technologies for detecting breast cancer can be developed, tested and put to use faster.
Researchers also must continue to refine their understanding of breast cancer risk factors, the report said, so that screening recommendations can be tailored to individual women. Genomic and proteomic tests or other biomarkers are technologies believed to have great potential, but Smith noted that these technologies are still in their infancy.
The report also called for better tools to help women and their doctors understand breast cancer risk. Many younger women overestimate their risk of getting breast cancer, while some older women underestimate theirs. A better understanding of breast cancer risk could help women make better choices about screening and other lifestyle factors that could influence this risk.