Use of Supplemental MRI Screening in Women With Extremely Dense Breast Tissue
Posted: Friday, January 3, 2020
Supplemental screening with MRI in women with extremely dense breast tissue resulted in the diagnosis of “significantly lower interval cancers” than with mammography alone, according to Marjie F. Bakker, PhD, of the University Medical Center, Utrecht, and colleagues. Results of the DENSE clinical trial (ClinicalTrials.gov identifier NCT01315015) were published in The New England Journal of Medicine.
The randomized, multicenter, controlled trial included 40,373 women between the ages of 50 and 75 with extremely dense breast tissue. All had normal results on prior mammography screening. Patients were grouped in a 1:4 ratio, with 8,061 receiving an invitation to receive MRI and 32,312 in the mammography-alone group. Of those invited to undergo MRI, 4,783 (59%) actually underwent the screening. The primary outcome was the difference in the incidence of interval cancers between those receiving MRI screening and those undergoing mammography alone.
In the MRI group, an interval cancer was diagnosed in 20 women (16 were invited but did not undergo screening; 4 participated in screening.) In the mammography-alone group, an interval cancer was diagnosed in 161 of 32,312 women. This screening resulted in an interval-cancer rate of 2.5/1,000 screenings in the MRI-invitation group and 5.0/1,000 screenings in the mammography-alone group.
The investigators noted that there was a cancer-detection rate of 16.5/1,000 screenings and a false-positive rate of 8% (79.8/1,000 screenings). They are currently using their results to evaluate the reduction in mortality and the extent of overdiagnosis, along with the effects on costs and quality of life to “improve early detection and reduce interval breast cancers in such patients.”
Disclosure: For the full disclosures of the study authors, visit nejm.org.