Over the past few years, the number of women whose doctors have suggested that they get an MRI after a breast cancer diagnosis has increased dramatically. But does this mean that these women are getting better, more effective medical care? Probably not, as a study presented at a meeting of the American Society of Clinical Oncology earlier this month revealed.
There is no evidence that having an MRI will improve your chances of surviving your cancer. What it will do, though, is make it more likely that you will have a mastectomy instead of a lumpectomy. Why? Because the super sensitive MRI is finding spots that were not seen on the mammogram.
To most people, this sounds like a good thing. But thatâ€™s why when it comes to treating cancer, itâ€™s important to question our assumptions. Those of us who have been in this field for a long time have been reminded of this again and again. In fact, many of us have seen this same situation before.
In the “old” days when we were beginning to study whether lumpectomy followed by radiation would be as effective as mastectomy, several studies were done where a lumpectomy was performed prior to the mastectomy. This allowed researchers to study the tissue that would have been left behind if only a lumpectomy had been performed. These studies found that there were times when specks of cancer would have been left behind after the lumpectomy, and they were used to argue against lumpectomy. But the radiation given after a lumpectomy will take care of those specks. How do we know? Because studies have shown that women who have a lumpectomy followed by radiation have the same survival rates as do women who have a mastectomy. So, the fact that these specks are there isnâ€™t new. Itâ€™s just that the use of MRI after mammography has focused our attention on them again. But nothing has really changed. More is not better.
But wait, youâ€™re saying, itâ€™s been all over the news that Christina Applegateâ€™s breast cancer was found because she had an MRI. That may be true, but thatâ€™s confusing the issue. This study looked at MRI after a cancer had been found on a mammography. Christina Applegate has been encouraging women to have an MRI to screen for breast cancer. But the fact is, MRI is not a great screening tool for all women. The problem is that MRI all too often results in a false positive result, which leads to unnecessary worry and medical testing. Further, because MRI only spots lesions that have lots of blood vessels, it may miss the slow-growing cancers that have only a small number of blood vessels. For high-risk women like Christina Applegate, who had a BRCA mutation, there may be some advantages to MRI screening. Thatâ€™s why in March 2007, the American Cancer Society updated its cancer screening recommendations to suggest that all high-risk women receive annual MRI screening in addition to mammography. But for most women, mammography remains the best screening tool.