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Breast cancer remained at the center of a debate in the year 2012. According to one recent analysis, regular mammograms have not reduced the rate of advanced breast cancers, but the exams have led more than a million women to be diagnosed with tumors that didn't need to be treated. Defenders of regular mammograms say the analysis is deeply flawed. And they're promoting new technology that promises to find even more and smaller breast tumors. With all these conflicting claims, some women are forgoing regular mammograms. Others are doubling down - getting radical treatment for precancerous tumors that many experts think would never cause harm. NPR's Richard Knox has the story.
RICHARD KNOX, BYLINE: To stake out the boundaries of this debate, I talked to three people with very different viewpoints. Shannon Brownlee has written books about what she calls American medicine's tendency to overdiagnose and overtreat disease.
SHANNON BROWNLEE: Right now, mammography is not presented as an individual choice. It is presented as a got-to-do-it.
KNOX: Dr. Daniel Kopans of Harvard is one of the fiercest advocates of routine mammograms.
DR. DANIEL KOPANS: Why would you ignore the opportunity to find something early, knowing that the science proves that it saves lives?
KNOX: And Dr. Otis Brawley is chief medical officer of the American Cancer Society, a prominent leader of the nation's cancer establishment.
DR. OTIS BRAWLEY: I do believe that about one in five women who have a localized breast cancer has a tumor that really does not need treatment.
KNOX: I asked myself how a woman can sort through the thicket of apparently irreconcilable opinions. Because really, she has no choice. Women over 40 have to decide what to do - or not do - about getting regular mammograms. Shannon Brownlee's made up her mind. She's 56, and she doesn't get regular mammograms. But it wasn't easy.
BROWNLEE: We have been told for, oh, almost a century now that catching cancer early is always a good thing. So when people come along and say, well, maybe screening might not always be such a great thing, it's very, very difficult to contemplate that.
KNOX: As she delved into the subject, Brownlee was impressed with the downside of routine mammograms. Over 10 years, annual mammograms will find something suspicious in 60 percent of women. And 35 percent will be told they need a breast biopsy. That will find breast cancer in about half a percent. And many experts believe some of those would never have caused a problem if they hadn't been diagnosed.
When Brownlee decided she didn't want an annual mammogram, that put her at loggerheads with her doctor.
BROWNLEE: She would say, You have to get a mammogram. And I would demur. And she would say, not a week goes by that a patient of mine didn't have her life saved by getting a mammogram. And I wanted to say how do you know, 'cause you can't know after the fact.
KNOX: That, in fact, is true. While studies show routine mammograms do save lives overall, even their staunchest advocates acknowledge you can't know in a particular case.
Eventually, Brownlee and her doctor worked it out. She said she'd get an occasional mammogram in her 50s, and promised the doctor she'd get treated if an invasive cancer was found.
Dr. Dan Kopans dismisses critics of mammography as unscientific. He has an answer to those who lament the high rate of falsely positive mammograms; those indicating something suspicious that turns out not to be cancer. He's invented a 3D mammogram called tomosynthesis.
KOPANS: I can page through the breast as if it's the pages in a book.
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KNOX: In a small closet of a room at the Massachusetts General Hospital, Kopans is demonstrating his invention. By the way, he says he has no financial interest in companies marketing the technology. It uses a computer to create 3D pictures of the breast. It subtracts a lot of the visual noise in 2D mammograms that obscures many breast tumors.
KOPANS: Now I'm pointing to a cancer that is much more easily seen because we've gotten what's in front and what's in back out of the way.
KNOX: Kopans says 3D mammograms, which the FDA approved last year, will drastically reduce the percentage of women who are called back after a routine mammogram for further tests, to see if there's something that needs to be biopsied. 3D mammograms will detect more and smaller breast cancers. That, after all, is the point.
KOPANS: It's pretty clear we detect more cancers with it.
KNOX: Would you say there's a potential problem here, that as you increase the detection of cancers, you're going to increase the detection of cancers that probably don't need to be treated?
KOPANS: I think that's a theoretical possibility. All I can say is that it's clear that finding smaller cancers saves lives. Now your question is, does finding more small cancers, is that better? The answer is, I would say it should be. I have no absolute proof.
KNOX: This concept may be strange. But a lot of cancer experts these days think not all cancers, including breast cancers, need treatment. Doctors call this overdiagnosis.
Dr. Otis Brawley of the Cancer Society worries that finding more small breast cancers will increase overdiagnosis.
BRAWLEY: Some of the 3D imaging machines are just spectacular in diagnosing small lesions. Now, we don't know that they're diagnosing small lesions that need to be diagnosed and need to be treated.
KNOX: But Brawley says research is underway to answer that important question.
BRAWLEY: We're on the verge of some tests to actually be able to say, Mrs. Smith, you've got breast cancer but it's the kind we need to watch. Mrs. Jones, you've got breast cancer, it's the kind that we need to treat.
KNOX: He thinks that's five to 10 years off. Meanwhile, the Cancer Society recommends that women get regular mammograms starting in their 40s, as long as they understand it may lead them into difficult choices about what to do next.
Richard Knox, NPR News.
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