Breast Cancer Screenings: What if You Have 'Dense Breasts'?
If you're a woman, there's a 40 percent chance you have what's known as dense breast tissue. The condition makes it harder to detect cancer in mammograms.
Nineteen states have now enacted laws that require doctors to notify women who have dense breasts. In Maine, the Legislature passed a resolve to make such notification voluntary. Either way, the diagnosis can be confusing, since there's no agreement among doctors about what patients should do next. Some suggest ultrasounds, but a study released this week found minimal benefits to them. All this is re-igniting the debate about the overall effectiveness of breast cancer screenings.
Ever since she was 40, Barb Deschenes was vigilant about having annual mammograms, and they always came back normal. But at age 55, about a month after receiving a normal mammogram result, her doctor felt two cysts on her breast during a routine check up. Deschenes went in for an ultrasound the next morning and discovered she had a tumor.
"So, of course, I was blindsided," she says. "Even though I knew from when I had my mammograms and they told me I had dense breasts, I had no idea that it meant they couldn't see in a mammogram - they couldn't see cancer."
Deschenes says she kicks herself for not asking about what it meant to have dense breast tissue. She might have sought additional screening and found the cancer earlier, avoiding at least a mastectomy, if not radiation and chemotherapy.
Deschenes didn't want the same thing to happen to other women, and she found support in the Connecticut-based organization "Are You Dense?" Founder Nancy Cappello calls dense breast tissue the best kept secret about women. Her experience began a decade ago.
"I had 11 normal mammograms, ate healthy, exercised daily, did my breast exams," Cappello says. "Little did I know I had this condition which 40 percent of women have called dense breast tissue. And as the density of a breast increases, the reliability of the mammogram plummets. Little did I know - no one ever bothered to tell me, even though it's been in the literature now two decades."
Six weeks after Cappello received a normal mammogram result, her doctor felt a ridge in her breast. A follow-up mammogram again came back normal. But a subsequent ultrasound found Stage 3C breast cancer. The experience spurred Cappello to form her organization, which has helped 19 states pass legislation requiring physicians to inform women when they have dense breast tissue.
Barb Deschenes spearheaded a similar effort in Maine in 2012. "There was a lot of skepticism," she says. "I found it was something people had no idea about."
The Legislature opted for a resolve to encourage doctors to voluntarily notify women with dense breast tissue. Maine Center for Disease Control Director Dr. Sheila Pinette was co-chair of the group that worked on the issue.
"I think the mandate would be like regulating the art of medicine or the science," Pinette says, "And most practitioners, if you mandate things, it would have to - how would you enforce that?"
Pinette says about 75 percent of mammography facilities in Maine are either working toward or already notifying women with dense breast tissue by letter when they receive their mammogram results. The letters encourage women to discuss their risk for breast cancer with their physicians.
"I think the resolve is just idiotic. It's zero. It's nothing," says Nancy Greene. Greene is another Maine woman with dense breast tissue who was diagnosed with cancer shortly after a normal mammogram. She says doctors should be legally required to inform women so they can get further screening, such as ultrasounds or an MRI.
But not everyone agrees that more screening is a good idea. "The goal of early cancer detection cannot be to find the most cancers possible. That's just too easy. The goal has got to be to find the cancers that matter," says Dr. H. Gilbert Welch, a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice.
Welch says the harder physicians look for cancer, the more they find and treat it. But some cancers, he says, will never be life-threatening.
"Often you'll hear stories of survivors - people who had a screen-detected breast cancer or prostate cancer - and they're doing well," he says. "And the way we interpret that story is this is someone who's benefited from the test. But in fact, it may be the person that's been harmed from the test - the person who was found with a cancer that was never going to bother them anyway."
Screenings also produce false positives. A study published this week on the use of ultrasounds as a supplemental breast cancer screening tool found a high rate of false positives that resulted in unnecessary biopsies.
Even mammograms have questionable effectiveness. Last February the results of a 25-year Canadian study involving 90,000 women found no benefit to mammograms. It also found that 1 in 424 women who did have mammograms had unnecessary treatment, including surgery, chemotherapy and radiation.
Both studies have stirred controversy. Barb Deschenes - the woman who spearheaded the effort to pass a dense breast tissue law in Maine - says the bottom line is women still have a right to know. "It's my body. I can make my choices," she says.
Complicating that choice is whether insurance companies will pay for follow-up breast cancer screenings. About a half-dozen states require insurance companies to cover supplemental screenings under various conditions. Deschenes says she plans to push for similar legislation in Maine.
Dr. Welch questions whether more screening will lead to improved outcomes. "It is not the best thing since sliced bread," he says. "We've overstated the benefits and understated the harms."
Welch says there's an uncomfortable reality with cancers: They're not all the same. Some grow very fast, and may not be detectable before they spread. But he sees hope in how treatment has improved survival. And he says continuing improvements in that treatment, combined with prevention through healthy lifestyle habits, might be the place to focus attention.