Women with a strong family history or certain genetic mutations face a greater-than-50% chance of getting breast cancer. With those frightening odds in mind, some decide to get preventive mastectomies to minimize cancer risk. The rest are screened frequently to detect cancer at its earliest stages, often with triple screening—mammography, ultrasound and magnetic resonance imaging (MRI). That catches more cancer than, say, mammography alone. But it also costs more and means more tests and doctor visits.
Now a new study finds that one of these “triple screening” tests is a waste of time and money…while another is an essential lifesaver.
THE POWER OF MAGNETIC RESONANCE IMAGING
The study, from Austria, looked at 559 women with higher than average risk of developing breast cancer. Their median age was 44, but their ages ranged from 22 to 83. Some of the women carried the dangerous BRCA1 or BRCA2 mutation while others had strong family histories of breast cancer, such as a mother or sister or daughter who’d had the disease.
Each woman had triple screening. If anything suspicious arose on any of the three screens, a biopsy was done. There were 204 “suspicious” findings which turned out to be 40 cancers. Here’s what the researchers found out about each type of screening…
• MRI was by far the best at detecting cancer, catching 36 of the 40 cancers—90%.
• Mammography alone, and ultrasound alone, each caught only 15 of the 40—38%.
• Mammography caught two cancers that MRI missed—5%.
• Ultrasound didn’t catch any cancers that weren’t already caught by either mammography or MRI.
• MRI was the best screening tool for correctly identifying cancer in women with dense breasts (more common in younger women).
• MRI was also the best screening tool for older women, regardless of breast density, and for women with certain genetic mutations.
MRI wasn’t perfect: It missed four cancers—the two that mammography caught, plus one that was not detected by any screening test but was discovered in a breast exam three months later, and a fourth that was revealed when one of the women in the study asked for a biopsy even though the study’s radiologist had graded the lump revealed by her MRI as “probably benign.” (There’s a lesson in patient empowerment here, but that’s another story.)
MRI also turned out to have a higher false-positive rate—not a good thing—identifying 147 findings as suspicious that turned out to be benign after biopsy, compared to 38 false-positives from mammograms and 41 from ultrasound. However, the researchers note, 46 of those MRI false-positives turned out to be atypical ductal hyperplasia, an advanced precancerous lesion that may warrant surgical removal, especially in women at high risk.
IS THE MRI-ONLY OPTION FOR YOU?
The new study makes it clear that for high-risk women such as those in the study, including an MRI in the breast cancer screening routine isn’t an option—it’s an absolute essential. If you get resistance from your health-care provider or insurance company, fight back. The authors of the study argue that for these high-risk women, an MRI screening at least once a year is an absolute must.
The new research also suggests that adding ultrasound to the mammography/MRI mix has no benefit.
And one piece of good news is that when cancers in women with a strong family history of breast cancer are found, they are no more difficult to treat than cancers in women at low risk. More testing, especially with MRI, means more false-positives, however, so be aware that everything that “looks suspicious” on your chart is not necessarily going to turn out to be cancer.
This study also raises the question of whether MRI could someday replace mammograms for some women. In this research, mammograms picked up an additional 5% of cancers…two out of 40…which, when all the numbers were crunched, wasn’t considered statistically significant by the researchers. Of course, it is significant if it’s your cancer that’s detected with mammography…or one in your wife, sister, mother or daughter.
MRIs continue to improve, but for now, the mammogram/MRI combo still looks like the best combination. If you are a woman at high risk for breast cancer, or love someone who is, insist on it.