A study by researchers at the University of Bonn has shown that magnetic resonance imaging (MRI) is more accurate than mammography in diagnosing very early stages of breast cancer.
A total of 7319 women were investigated by Professor Kuhl and her colleagues over five years using both methods. In 167 of them they found early stages of breast cancer. Mammography only detected 93 cases of DCIS, compared with 153 cases detected by MRI. “And not only that: it was above all the particularly aggressive high-grade DCIS which were especially reliably picked up using MRI, but especially difficult to detect using mammography,” said Professor Kuhl.
A total of 89 cases of high-grade DCIS were discovered by the doctors in the course of the study. MRI, detected 98% of these aggressive pre-invasive breast cancers, while mammography only detected 52%. The reason for this was that as it appears that the fast-growing tumours do not develop the calcifications which constitute the basis of mammographic DCIS diagnosis. Instead, these DCIS are pervaded by many small blood vessels in which the contrast medium that is injected for an MRI scan collects particularly well.
These finding concur with other studies. Below is an article written by Sandie Walters of “DCIS Without Rads.”
Unfortunately, mammograms miss 20-25% of all cancers. They also underestimate the size of DCIS in a third of all lumpectomy patients. When this happens, the surgeon misses some DCIS and another surgery is needed. MRIs, which use magnets rather than radiation, can find what mammograms miss. According to a 2010 JNCI article by Dr. Constance Lehman : “Over the last decade, research has confirmed that of all imaging tools, MRI has the highest sensitivity in detection of DCIS (compared with mammography and ultrasound).” Although MRIs are considerably more expensive than mammograms, avoiding a re-excision would not only be less costly but also less traumatic.
The Aurora RODEO MRI offered at 35 locations in the United States, is a dedicated MRI, meaning it is used only for breast imaging. Its unique technology provides sharper 3-D images and better resolution than a standard whole body MRI. According to Dr. Steven Harms, referring to the RODEO MRI in a 2006 interview for Radiology Today, “We get three times the signal-to-noise ratio (SNR) of most 3DFT images. We’re using that SNR to improve resolution and improve the contrast resolution. And there are significant gains in both of those. The image resolution by the number of voxels we generate is three times that of what we had before. We also reduce scan time, which is less than half of what it was and contrast is about twice what it was before. It’s a considerable gain.”
In fact, a 2012 study by Dr. Bruce J. Hillman etal showed that, while the false negative rate for whole body MRI has historically averaged 15%, the false negative rate for the RODEO MRI is less than 1%. In other words, if a RODEO MRI finds no cancer, there is only a 1% chance that it missed something, while with whole body MRI there is still a 15% chance cancer was missed. This study also showed that while whole body MRI has been criticized for its high false positive rates, typically between 32 and 41%, RODEO MRI has a very low false positive rate of only 11%. This means if a RODEO MRI finds something suspicious, the chances of an unnecessary biopsy are much lower.
With such good numbers, the Aurora RODEO MRI is a highly accurate and useful imaging tool, especially for DCIS. With its 1% false negative rate, it can provide peace of mind as an annual screening device for higher risk patients. Its accurate 3-D mapping can also assist surgeons in providing more tailored excisions and biopsies of DCIS that cannot be seen on a mammogram, while its low 11% false positive rate protects patients from unnecessary biopsies.
Dr. Michael Lagios states any “dedicated” breast MRI is as effective as the Aurora RODEO MRI.