Breast Density Laws, New Technologies Driving Increased Use of Supplemental Imaging
Karla Kerlikowske, MD, a co-principal investigator of the Breast Cancer Surveillance Consortium (BCSC), is part of the team awarded $7.5 million by the Patient-Centered Outcomes Research Institute (PCORI) board of governors to determine the effectiveness of two supplemental breast screening and diagnostic workup strategies.
Kerlikowske, a professor of Medicine and Epidemiology and Biostatistics at UCSF, and Diana Miglioretti, UC Davis dean’s professor of biostatistics, will work to determine the effectiveness of digital breast tomosynthesis (3-D mammography) and magnetic resonance imaging (MRI) as well as whether the effectiveness depends on a woman’s breast density.
The award was one of four from the PCORI board of governors that will examine various care options for treatment of a range of conditions and problems that impose high burdens on patients, caregivers and the healthcare system.
Kerlikowske and her colleagues will use data from the BCSC, the nation’s largest collection of information on breast imaging. The BCSC consists of six breast imaging registries across the U.S., including the the BCSC’s Statistical Coordinating Center located at the Group Health Research Institute in Seattle, Wash. Other co-principal investigators include Tracy Onega, PhD, and Anna Tosteson, ScD, at Dartmouth College.
Supplemental Screening is Growing Rapidly
Understanding the role of supplemental screening is extremely important because its use is growing rapidly, but too little evidence exists to prove if it is effective. Tomosynthesis, also known as 3-D mammography, is of particular concern because about half of the mammography centers now offer the technology and many radiologists in the U.S. are using it for screening all women. The technology is added to an existing mammography machine and turned on during a screening for the added 3-D imaging.
“3-D mammography holds great promise of improving breast cancer detection of aggressive tumors and decreasing the rate of false alarms,” said, Kerlikowske, who is also a member of the UCSF Helen Diller Comprehensive Cancer Center. “We want to know whether performing the test adds clinical value, in particular in women with dense breasts, obviating the need for screening ultrasound or MRI.”
Complicating the breast screening landscape is that more than half of states now have breast density laws that require notifying women if they have dense breasts. These laws aim to inform women of the increased risk of breast cancer and the fact that mammography is not as effective at finding breast cancers in women with dense breasts. An estimated two-thirds of premenopausal women and one-quarter of post-menopausal women have dense breasts, and many are now getting some kind of supplemental imaging beyond digital mammography.
Studying MRI Use in Surgical Planning
In addition to an examination of supplemental breast imaging for screening, Kerlikowske and colleagues will study whether using breast MRI prior to surgery enhances surgical planning in women with a newly diagnosed breast cancer, particularly for women with dense breasts, and if it ultimately reduces the rate of breast cancer recurrence. The aim is to determine whether a pre-operative MRI finds additional cancers that are life threatening.
The PCORI award is one of many that Kerlikowske and Miglioretti have received to use BCSC data for analysis of breast screening strategies to better inform clinical practice and help women make the best screening decisions. Kerlikowske and colleagues also developed the BCSC risk calculator that is being used to identify women with dense breasts at high risk of missed cancers.
The PCORI board approved the breast screening research award pending completion of a business and programmatic review by PCORI staff and issuance of a formal award contract. PCORI is an independent, nonprofit organization authorized by Congress in 2010 to fund research that will provide patients, their caregivers, and clinicians with the evidence-based information needed to make better-informed health care decisions.