Some researchers recommend starting mammogram screening at age 40, while others say age 50. Some doctors think screening should be based on a woman's overall risk for breast cancer, not just her age. Hero Images/Corbis hide caption

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It's a good start when experimental compounds stop the proliferation of cancer cells in the lab. But, as many researchers have learned the hard way, that's just an early step toward creating a worthwhile treatment. Science Source hide caption

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Mary Harris was relieved when Stella was born with a mop of thick black hair, as if she had been protected from the chemo somehow. Courtesy of Howard Harris hide caption

itoggle caption Courtesy of Howard Harris

Radiation therapy is effective in treating breast cancer but typically requires dozens of visits over five to seven weeks. A newer protocol takes just three weeks. Antonia Reeve/Science Source hide caption

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Women participate in a breast cancer fund-raising in Denver in 2011. Despite decades of awareness campaigns, the survival rate for women with metastatic breast cancer hasn't improved. Helen H. Richardson/Denver Post/AP hide caption

itoggle caption Helen H. Richardson/Denver Post/AP

Coalitions of patient advocates now help steer research funding toward particular projects. Lilli Carré for NPR hide caption

itoggle caption Lilli Carré for NPR

Lisa Schlager of Chevy Chase, Md., demonstrates outside of the Supreme Court as arguments were made in a case seeking to determine whether the BRCA breast cancer genes can be patented. The court ruled in 2013 that individual genes can't be patented. Tom Williams/CQ Roll Call/Getty hide caption

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TV host Samantha Harris says she will have a double mastectomy after being diagnosed with breast cancer. But the surgery doesn't eliminate cancer risk. Jordan Strauss/Invision/AP hide caption

itoggle caption Jordan Strauss/Invision/AP

Mary-Claire King says obscurity gave her the freedom to spend years looking for breast cancer genes. Mary Levin/University of Washington hide caption

itoggle caption Mary Levin/University of Washington

Mammograms are a key screening tool for breast cancer. But critics say they're not good enough. Salih Dastan/iStockphoto hide caption

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