Consecutive Mammography Screening and Risk of Breast Cancer Mortality
Posted: Monday, May 17, 2021
Women who attended the two scheduled mammography appointments before their breast cancer diagnoses had higher 10-year and overall survival rates than did those who missed one or both screenings, according to Stephen W. Duffy, MSc, of Queen Mary University of London, and colleagues. These findings were published in the journal Radiology.
“Regular participation in screening mammography is necessary to optimize the reduction in risk of dying from breast cancer,” stated the study authors. “Missing even one screening examination confers a significant increase in risk.”
The researchers analyzed data from 549,091 women eligible for screening mammography in Sweden between 1992 and 2016. The women were categorized as serial participants if they attended their last two scheduled mammographies before diagnosis, intermittent if they attended just the previous scheduled mammography, lapsed if they only attended the second to last, and serial nonparticipants if they attended neither.
Serial participants had a 49% relative risk reduction (P < .001) of dying from breast cancer and a 50% lower risk (95% confidence interval [CI] = 0.48–0.55, P < .001) than serial nonparticipants. Intermittent participants saw a 33% reduction (95% CI = 0.59–0.76, P < .001) and lapsed participants saw a 28% reduction in mortality (95% CI = 0.63–0.83, P < .001) compared with serial nonparticipants.
The incidence of cancers that proved fatal within 10 years was 50% lower for serial participants versus serial nonparticipants (95% CI = 0.46–0.55, P < .001). The reduction was 36% and 25% (P < .001) for intermittent and lapsed participants, respectively.
Researchers acknowledged the limitations of their observational study. First, not all data were available because some patients were treated at private facilities. Second, they had no data on confounding factors.
Disclosure: For full disclosures of the study authors, visit pubs.rsna.org.
