Women who receive a false-positive mammogram are more likely to delay subsequent screenings compared with women who have true negative mammograms, according to a study published in Cancer Epidemiology, Biomarkers & Prevention.
Researchers from the University of Illinois at Chicago undertook the study to examine the impact of a false-positive screening mammogram on subsequent screening mammography behavior, such as a delay of more than 12 months from index mammogram to the next one, and resulting cumulative risk.
Data from 741,150 screening mammograms from 261,767 women were obtained through a large health care organization with multiple facilities in the greater metropolitan Chicago area. Of these mammograms, 12.3% (90,918 exams) yielded a false positive result, the remaining 87.7% (650,232 exams) yielded true negative results.
The results from the database showed that receiving a false-positive mammogram did result in delays for subsequent screening:
|True Negative||False Positive|
|Likelihood of subsequent mammograms||85%||77.9%|
|Median delay in returning to screening||3 months||13 months|
|Four-year cumulative risk of late stage at diagnosis*||0.3%||0.4%|
*This difference was statistically significant.
"Because we obtained the same conclusion using two different statistical approaches to analyze the data, we have a high degree of confidence in the results," Firas M. Dabbous, PhD, manager of patient centered outcomes research at the Russell Institute for Research & Innovation at the Advocate Lutheran General Hospital in Park Ridge, Illinois, said in a release. "We believe that the delay in subsequent screening for women who have an initial false positive result increases the probability that they will subsequently receive a later-stage breast cancer diagnosis compared with women who first have a true negative result from a screening mammogram."