Women with a higher risk of breast cancer and dense breast tissue commonly get an annual mammography. But an ultrasound screening or MRI on top of the regular checkup significantly boosts the rate of cancer detection, a new study concludes.
The research, detailed in the April 4 edition of The Journal of the American Medical Association, helps validate the regular use of both machines in preventative care for patients at high risk for breast cancer. Such a finding, however, potentially clashes with efforts driven by the healthcare reform law and insurers to manage, and limit the use of expensive imaging equipment. It will be interesting to see how policymakers and elements of the healthcare system respond to the findings in the coming months.
One caveat for the research: While MRI machines are more sensitive for cancer detection, the researchers said in a statement that adding MRI screenings to mammography instead of using a supplemental ultrasound screening may not be the best for women with dense breasts at "intermediate" risk for breast cancer. For this patient population, the high cost, combined with MRI false positive rates reduces the viability of preventive MRI screenings. As Bloomberg notes in its coverage of the research, false positives lead to lots of unnecessary biopsies.
Dr. Wendie A. Berg, most recently with the American College of Radiology Imaging Network in Philadelphia and now at the University of Pittsburgh School of Medicine, worked with a number of colleagues on the research, which evaluated 2,809 women with increased cancer risk and also dense breasts. The scientists conducted their study at 21 different sites. All of the women, at an average age of 55 at the start of the study, agreed to three annual independent screens with mammography and ultrasound, to be given randomly. More than half had breast cancer previously.
The extra ultrasound helped boost cancer detection, beyond mammography, by 5.3 cancers per 1,000 women in the first year and 3.7 per 1,000 in the next two annual screenings. Overall, a bonus ultrasound caught 29% more cancers than just mammography alone, Bloomberg explains. Additional MRI screening kicked that number even higher, boosting cancer detection after an initial mammography by a rate of 14.7 per 1,000 women.
Here are some additional numbers to chew over: The team needed to conduct 127 mammography screens to identify one cancer, and 234 for an extra ultrasound. Just 68 were needed for a supplemental MRI to detect a cancer, after a mammography and ultrasound screening produced negative results.