New Law Improves Breast Cancer Detection

March 28, 2013


CALIFORNIA – A new law taking effect April 1 will improve breast cancer detection in women with dense breast tissue. Senate Bill 1538, authored by former State Senator Joe Simitian, will require that following a mammogram, women with dense breast tissue be informed of the following:

  • They have dense breast tissue;
  • That dense breast tissue can make it harder to evaluate the results of a mammogram;
  • That it is associated with an increased risk of breast cancer;
  • That information about breast density is given to discuss with their doctor; and
  • That a range of screening options are available.

Dense breast tissue both makes the cancer more difficult to discern on a mammogram and increases a woman’s risk of cancer. The new law requires women to be told if they have dense breast tissue and, for those who do, suggests that they discuss with their doctor whether further screenings would be advisable.

Now a Santa Clara County Supervisor, Simitian said, “By requiring information on dense breast tissue, the law now ensures that women are better informed about their bodies and will help them make better decisions about the medical screening or care they might need.”

Simitian will hold a telephone “Town Hall” about the issue of early detection and the importance of the new law on April 7 from 11:00 a.m. to 12:00 p.m. To participate, call (866) 476-7782.

The law originated as a suggestion from one of Simitian’s constituents, Amy Colton of Santa Cruz, a registered nurse, who participated in Simitian’s annual “There Oughta Be a Law” contest. Colton was shocked when she was told she had breast cancer after years of normal mammograms. She learned that she had dense breast tissue only after her cancer treatment.

“Early detection of cancer is the key to saving lives, which is the most important aim of this law,” said Simitian. “But it also reduces health care costs, because cancer caught early can be treated less expensively and with less hardship to the patient.”

About 40 percent of women have dense breast tissue, but an overwhelming majority of women are unaware of their breast density. The risk of breast cancer for women with extremely dense tissue is five times greater than for those with low breast density. A study by the Mayo Clinic in 2011 found that 75 percent of cancers in women with dense breast tissue were missed by mammography alone. Both the cancer and the dense tissue appear white on a mammogram.

The legislation, Senate Bill 1538, was signed into law by Gov. Jerry Brown following the 2012 legislative session. As it moved through the Legislature, it gained the support of the California Radiological Society, the California Nurses Association, Planned Parenthood Affiliates of California, the California Affiliates of the Susan G. Komen Foundation, and the Breast Cancer Fund.

“I’m gratified that doctors are now required to share this vital information with patients,” said Simitian. “But in addition, those concerned about women’s health should continue to do all they can to make women aware of this issue, to encourage them to ask the right questions about their cancer risk and about appropriate preventative measures.”

For more about SB 1538, visit and click on the “Are You Dense” icon. For more information about dense breast tissue, visit or  Breast Health Center.



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