The ideal interval for breast cancer screening depends on combined assessments of each woman’s breast cancer risk and her breast density, according to a new study led by UC San Francisco and University of Wisconsin (UW) researchers. The research team, members of two nationwide breast cancer research networks, found that women at high risk who also have dense breast tissue may benefit from annual screenings – more frequent than current guidelines, which call for mammograms every two years – while women at average risk with low breast density would be best served by screenings every three years.
As reported in the Aug. 23, 2016, issue of Annals of Internal Medicine, researchers in the Breast Cancer Surveillance Consortium (BCSC) and the Cancer Intervention and Surveillance Modeling Network (CISNET) collaborated on the new study, which used population-based breast cancer screening information incorporated into computer models to predict long-term health outcomes based on different screening intervals.
“Our whole goal is to tailor breast cancer screening – it’s a concept we’ve tried to promote for many years,” said Karla Kerlikowske, MD, co-first author of the new study and a member of the UCSF Helen Diller Family Comprehensive Cancer Center. Kerlikowske was joined by co-first author Amy Trentham-Dietz, PhD, of the UW Carbone Cancer Center, and co-senior authors Jeanne Mandelblatt, MD, MPH, of Georgetown University’s Lombardi Comprehensive Cancer Center, and Anna Tosteson, ScD, of the Geisel School of Medicine at Dartmouth.
Using population-based data gathered by the BCSC, the researchers modeled health outcomes for women aged 50 to 74 under regimens calling for screening every one, two or three years. They then combined results from three different microsimulation models, developed by CISNET, to determine optimal screening intervals. The models were calibrated to current breast cancer screening, incidence, and treatment in the United States. “These models are very applicable to the populations we screen,” Kerlikowske said.