A new review of existing evidence suggests that using magnetic resonance imaging to "stage" a woman's breast cancer before surgery might do more harm than good.
MRI produces a much clearer image than X-rays and ultrasound, and is recommended for detecting early tumors in women at increased risk for breast cancer. But routinely using the technology once any woman is diagnosed with a tumor may lead to more radical surgery without any benefits, says a team of Australian and U.S. researchers.
They found that about 26 percent of women who had a pre-operative MRI to help determine the extent and severity of their tumor ended up having their entire breast removed, compared to about 18 percent of those whose surgeons only used traditional methods of characterizing the cancer.
"I wasn't surprised by the results at all. What I am surprised by was the strength of the data," said Dr. Monica Morrow, the study's senior author and the chief of breast service at Memorial Sloan-Kettering Cancer Center in New York.
Because MRIs are more sensitive than mammograms, some doctors think they are a good tool for identifying the precise outlines of cancerous tissue. Others, however, have begun to question whether the imaging led surgeons to remove more breast tissue than necessary.
Moreover, women who have MRIs before breast surgery seem to be no less likely to need a second surgery to remove additional cancerous tissue.