Mammography risks and benefits

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By Christina O'Haver By Christina O'Haver

PHOENIX -- When it comes to cancer, many doctors agree that early detection can save lives.

But new information suggests that doctors may have played up the benefits of mammography and underestimated the risks.

“I drove home and there was a lump in my throat,” said Sherry Gage, remembering a mammogram at age 40 that spotted something suspicious. “I could see it -- the size of three grains of salt.”

Gage couldn't feel the cancer but the mammogram caught it.

“I found it so early, I didn’t need treatment. That's why screening mammograms are so important,” she said.

But despite Gage's success story, recent studies suggest doctors may have oversold the benefits of mammography and underplayed its risks.

The latest such study comes from Harvard University and Brigham and Women's Hospital. It calculated that 10 in 10,000 women in their 50s screened annually for a decade will avoid a breast cancer death. On the other hand, 6,130 women will have a false positive result that requires extra X-rays, and 940 will undergo biopsies for nonmalignant findings.

The study found that mammograms decrease a woman’s risk of dying from breast cancer by a modest 19 percent. Women in their 40s had just a 15 percent reduction in their breast cancer death risk compared with a 32 percent reduction for women in their 60s, who are far more likely to get breast cancer than younger women.

Dr. Linda Greer practices radiology at the John C. Lincoln Breast Health and Research Center.

“One main point was too much false diagnosis or over-diagnosis or false positives which means you were called back and it doesn’t end up being cancer,” Greer noted.

But she added that the study doesn't take new technology into account.

“Now with new 3-D technology, we separate out the layers of tissue so we’re not calling back people as much for additional views,” she explained.

John C. Lincoln was first in the nation to offer the 3-D screens three years ago.

Greer said, “My callbacks for spot compression views have gone down over 90 percent since we got 3-D mammography, so that negates a lot of this debate over false positives and harmful mammograms.”

Greer doesn’t believe that any biopsies are really unnecessary because, “we have no magic crystal ball that tells us which is which, so we have to find it and diagnose.”

She would like to see more studies focused on the newer technology.

Meanwhile, Gage, a single mom and breast cancer survivor, is now the director of the Breast Health and Research Center.

Given her experience, she encourages everyone to follow the American Cancer Society’s guidelines on recommended mammograms, which is to get a baseline screening between the ages 35 and 39 and then annually after 40.

“It's a scary thing to go through but I’m very glad I had the mammogram," she said.