Legislation introduced in the U.S. House of Representatives would require that women be informed of their breast density when they receive their mammogram results, and that those with denser breasts be advised that they could benefit from additional screening.

The Breast Density and Mammography Reporting Act of 2011 (H.R. 3102), introduced in October by Rep. Rosa DeLauro (D-Conn.) and Rep. Steve Israel (D-N.Y.), is modeled after laws enacted in Connecticut in 2009 and in Texas earlier this year. Similar legislation was recently passed by the California legislature, but was vetoed by the governor.

Bills on breast density are also slated to be introduced in at least six other states next year, according to the consumer advocacy group Are You Dense.

The movement to pass these bills has grown largely from the outrage of women who have received years of normal mammogram results only to find out that they have an advanced-stage breast cancer that went undetected because of their dense breast tissue.

That was the experience of Are You Dense founder Nancy M. Cappello, Ph.D., who successfully lobbied lawmakers to enact the Connecticut legislation.

Although information on breast density is available on the mammography report sent to referring physicians, it’s not mentioned in the "lay letter" received by women, Dr. Cappello said. That leaves most women in the dark about the fact that dense breasts can make mammograms more difficult to read, and that women with extremely dense breasts are at a higher risk for breast cancer, she said.

"It’s a hoax in some respects, a cruel hoax," she said.

Are You Dense and its supporters around the country have been working state by state to enact laws that require that women be notified of their breast density and their options for additional screening. They are also working at the federal level to change either the law or the regulations surrounding mammography.

Dr. Cappello said that trying to legislate the change wasn’t her first choice, but without a national cancer organization or physician group stepping up to educate women, she doesn’t have a better option for standardizing the communication on breast density.

On Nov. 4, Dr. Cappello will take her case to the Food and Drug Administration’s National Mammography Quality Assurance Advisory Committee. She plans to ask the committee, which provided nonbinding advice to the FDA, to recommend changing the federally mandated lay letter to include information on breast density.

So far, Dr. Cappello’s efforts have failed to gain support from major physician groups and patient advocacy organizations. Susan G. Komen for the Cure and the American Cancer Society both stayed on the sidelines during the recent legislative debate in California. The California chapter of the American College of Obstetricians and Gynecologists and the California Medical Association opposed the bill.

"It was a very difficult bill for us to oppose," said Dr. Philip Diamond, a San Diego ob.gyn. and chair of ACOG District IX in California.

The problem was that the bill went beyond notifying women about their density and on to suggest that they speak with their physician about supplemental screening. The bill’s language on supplemental screening goes beyond the existing evidence, Dr. Diamond said, and raised a host of concerns about what the cost of screening would mean for state-funded health programs.

"In the absence of a guideline nationally by either the cancer society or the radiology society or anyone, it’s impossible to be able to figure out who needs supplement screening and who doesn’t," he said.

A big concern in California, Dr. Diamond said, is that such legislation would lead to the automatic ordering of supplemental ultrasounds and MRIs, regardless of the individual risk factors of the women involved.

That’s exactly what has happened after the Connecticut law was enacted, according to New Haven ob.gyn. Howard Shaw, vice chair for the Connecticut section of ACOG.

Although the law has probably raised some awareness of the breast density issues for women, it has also sparked a reflexive ordering of supplemental testing for any women with dense breasts, he said, adding that the ordering is largely driven by liability concerns.

"There is a feeling by many that we’re just going to order it because if we don’t order it and something happens, we’re going to have a problem," said Dr. Steven Fleischman, associate chief of ob.gyn. at Yale–New Haven Hospital and the legislative chair of ACOG District I.

Another problem with the Connecticut law is that there’s a lack of data on how it’s working, he said. Because there was no tracking component built into the law, there are many lingering questions about the number of supplemental tests, the additional costs, and whether more cancers are being detected earlier, he said.

"It’s not just about cost; it’s about ‘Are we getting more cases, and are we getting them earlier,’ " Dr. Fleischman said.

Political Battles Brew Over Breast Density