Advances in Detecting Breast Cancer at Mayo Clinic
By Candice Russell
Finding breast tumors as early as possible is a major concern of doctors
and researchers. It's the best way to stop the spread of the disease and ensure
that women live longer. Making headway in this exciting field is a team of
doctors at the Mayo Clinic in Rochester, Minnesota who are investigating
molecular breast imaging. "The concept has been around for about twenty
years," says Dr. Carrie Hruska, a research fellow in Mayo Clinic's department
of radiology. "But gamma cameras able to find small breast cancers weren’t
developed at that time so it never took off. In the last ten years, very small
cameras specifically designed for breast imaging have been developed. Our
research contribution is on the technological end."
The technique, which has yet to be applied beyond a clinical setting, is
described by Dr. Hruska as "a way to detect differences between cancer
cells and normal cells. We use a radio-tracer, which is a drug known to accumulate
in abnormal cells. Attached to it is a gamma emitter, which will emit radiation
we can detect. We're still studying to see if it will be better than a
mammogram, but we know this method can detect tumors missed because of the
density of breast tissue. We found in our research that even large tumors can
be missed in mammograms if there is dense breast tissue. We image the behavior
of the cancer cells, not just their anatomical structure. This process is in
the investigative stage to see what role this method might play, perhaps as an
adjunct to mammography for women who have dense breasts and are at increased
risk of developing breast cancer."
So far the results are promising for molecular breast imaging, yet the
ability of mammography to save lives needs to be respected, in spite of its
limitations. "Everyone above age forty should get a mammogram," says
Dr. Hruska, recognizing it as the standard detection device. "Even with
all the new research, only mammography has
been proven to reduce deaths due to breast cancer. Molecular breast
imaging found three times as many cancers in dense breast tissue as the
mammograms did. We screened close to 1,000 women with both methods -- three
were found to have cancer when screened by mammogram and ten were found to have
cancer when screened by molecular breast imaging. This information is
motivating us to do more testing to see what role molecular breast imaging
could play in the clinic. Beyond screening, we plan to study what this method
can do to evaluate the breast before surgery. It could be a valuable clinical
tool."
There are other options for additional
testing, says Dr. Hruska. Women who are at a higher risk of developing breast
cancer, due to a genetic predisposition or other reasons, are now recommended
to have a magnetic resonance imaging (M.R.I.) procedure for their breasts.
"While it has a high ability to detect cancer, it can give a false
positive," cautions Dr. Hruska. "There's also a very high cost
involved. It's best to discuss the procedure with your doctor."
The Mayo Clinic is looking at breast cancer in a new way. "A lot of research at our institution has been about how to assess breast cancer on an individual basis," says Dr. Hruska. "We're getting away from the one-size-fits-all concept. I'm really excited about our research. I've been working on molecular breast imaging for six years. It was supposed to be part of my graduate school project and I just stayed on because I'm working with such a great team and we know women have really benefited. We are truly committed to finding better ways to detect breast cancer earlier."