That which doesn’t kill us may, in fact, be a valuable diagnostic tool

In women under 40, mammograms are less accurate and the radiation is potentially more dangerous. But hereditary breast cancer often strikes women under 40.

“Maybe after age 30 the risk of cancer is high enough to justify the potential long-term risk of cumulative radiation,” said Dr. Olufumilayo Olopade, director of the cancer risk clinic at the University of Chicago Medical Center. “So we traditionally recommend that high-risk women—especially mutation carriers—start screening with mammography at 25.

“This [study] calls into question, is it possible by starting so young we might increase their risk?”

MRI could eventually become the preferred screening tool for high-risk women, said Olopade, who wrote an editorial accompanying the study. But it’s not a perfect solution.

MRI alone can be hard to read and have a high rate of false-positive results, which lead to unnecessary biopsies, said Dr. Virginia Kaklamani, an expert in breast cancer and cancer genetics at Northwestern University.

So, if a radiologist found something suspicious on an MRI, she said, “I’d probably recommend a mammogram” despite the radiation exposure.

“Until we have more research,” Kaklamani said, “younger women with a genetic susceptibility to breast cancer are between a rock and a hard place.”

David Goldgar, a genetic epidemiologist at the University of Utah and lead author of the study, said it is too soon to draw conclusions about who should or should not have screening mammograms. He said further research was needed to confirm the results.

The study “is not enough to mandate changes in clinical practice,” said Dr. Kathy Albain, director of the breast research program at Loyola University Medical Center in Maywood. “But I think it’s enough to modulate our recommendations for certain patients.

“If you have very young patients who are also BRCA carriers, maybe you don’t send them for a chest X-ray at the first cough,” she said.

Kaklamani said women known to be mutation carriers might also think twice about getting mammograms before age 35.

The European study did not look at breast X-rays, but the radiation exposure with a mammogram is significantly higher than that with a standard chest X-ray.

The researchers hypothesized that radiation might be very risky for BRCA mutation carriers because those genes are believed responsible for repairing DNA damage. Defective genes would be less able to repair radiation damage.

Dr. Lydia Usha, who runs the RISC (Rush Inherited Susceptibility to Cancer) Center at Rush University Medical Center, said more high-risk women might decide to have prophylactic mastectomies—surgical removal of both breasts—if the study results are confirmed. Most patients don’t choose that option now.

Maria Pradd, 38, is one of Kaklamani’s patients. A former sales training and development manager, Pradd was diagnosed with breast cancer in 2004. Only after having a lump removed and undergoing treatment did she discover she had a BRCA1 mutation.

Pradd said she will consider having her ovaries removed after she has children, to reduce her risk of getting both ovarian and breast cancer. But she is not interested in prophylactic mastectomy.

She’s philosophical about risk, and about how far she’s willing to go to reduce it. “I know my chances of having another cancer are greater now,” said Pradd. “But I could also walk across the street and get hit by a bus.”

She said she would like to add an annual MRI to her screening regimen, but her insurance carrier so far has balked. A breast MRI can cost between $1,000 and $3,000. Mammograms are about a tenth of that.

The odds of having one of the known breast cancer genes is about 1 in 800 in the general population, said Usha. But it can be much higher in certain ethnic groups, such as the 1 in 40 figure for Ashkenazi Jews, or Jews of Eastern European origin.