Anna N. A. TostesonINTERIM DIRECTOR AND PROFESSOR
Until the early 2000s, almost all mammograms were film. Then, film was largely replaced by digital mammograms, followed in recent years by the growth in 3D mammography (also known as tomosynthesis). As new screening options, screening guidelines, and treatments emerge, there is a growing need to investigate not only effectiveness of screening options and treatments but how women understand and view these options. A Dartmouth Institute research team, led by Professor and Interim Director of The Dartmouth Institute Anna Tosteson, ScD, is working on several projects to evaluate breast cancer screening and treatment. The projects are part of Dartmouth Institute’s ongoing work with the Breast Cancer Surveillance Consortium (BCSC). Established by the National Cancer Institute in 2004, the BCBS houses the nation’s largest collection of mammography data from breast cancer screening in community practice.
How we’re meeting it
More than half of the states in the United States have passed laws requiring that women be notified if they have mammographically dense breast tissue. While laws vary from state to state, they typically involve mailings suggesting that such women may benefit from screening beyond mammography. Dr. Tosteson’s team is evaluating the benefits, harms, and cost-effectiveness of supplemental screening among women with dense breasts, including 3-D mammography and breast ultrasonography, which is a diagnostic imaging technique utilizing reflected high-frequency sound waves. To evaluate breast ultrasound, the research team undertook collaborative modeling with three Cancer Intervention and Surveillance Modelling Network (CISNET) breast cancer simulation modeling groups. They estimated the screening outcomes for mammography screening alone compared with mammography screening followed by breast ultrasonography. They found that supplemental ultrasonography would greatly increase costs with relatively small health benefits.
In contrast, in another simulation study of supplemental 3-D mammography screening, they identified parameters under which 3-D mammography screening would have the potential to provide health benefits without a substantial increase in costs. They concluded that while further study is needed for 3-D mammography, supplemental ultrasonography screening is of limited value.
While further study is needed for 3-D mammography, supplemental ultrasonography screening is of limited value.
Dr. Tosteson’s team also undertook a study on women’s perceptions of risk-based screening utilizing four focus groups of women 40-74 who had no history of breast cancer. The focus groups consisted of semi-structured interviews during which women were asked questions about their prior mammography experiences, knowledge of breast cancer risk factors, and concepts of breast cancer risk. They were then given an information sheet with updated guidelines for risk-based screening, a list of risk factors for breast cancer, and data about overdiagnosis. Women had mixed opinions on whether to accept risk-based screening. Some thought it made sense, whereas others felt confused about changing guidelines as well as how the risks were being assessed. They also worried that the new guidelines might be based on a health system’s financial concerns and not on medical reasons. The research team concluded that broad acceptability of risk-based screening will require clearer communication about its rationale and feasibility and consistent messaging from healthcare teams.