Fewer Interval Cancers Diagnosed With Supplemental MRI for Dense Breasts
Use of supplemental MRI results in diagnosis of fewer interval cancers than mammography alone
WEDNESDAY, Nov. 27, 2019 (HealthDay News) -- For women with extremely dense breast tissue and normal results on mammography, the use of supplemental magnetic resonance imaging (MRI) results in diagnosis of fewer interval cancers than mammography alone during a two-year screening period, according to a study published in the Nov. 28 issue of the New England Journal of Medicine.
Marije F. Bakker, Ph.D., from the University Medical Center Utrecht in the Netherlands, and colleagues randomly assigned 40,373 women aged 50 to 75 years with extremely dense breast tissue and normal results on screening mammography to undergo supplemental MRI or mammography screening only (8,061 and 32,312, respectively).
The researchers found that the interval-cancer rate was 2.5 and 5.0 per 1,000 screenings in the MRI-invitation and mammography-only groups, respectively. Fifty-nine percent of the women invited to undergo MRI accepted the invitation. Of the 20 interval cancers diagnosed in the MRI-invitation group, four and 16 were diagnosed in women who underwent MRI and in those who did not accept the invitation, respectively (0.8 and 4.9 per 1,000 screenings, respectively). Among women who actually underwent MRI screening, the MRI cancer-detection rate was 16.5 per 1,000 screenings; the false-positive rate was 79.8 per 1,000 screenings. The positive predictive values were 17.4 and 26.3 percent for recall for additional testing and biopsy, respectively.
"The findings of this trial are likely to reinforce the idea that MRI screening is important in women with dense breast tissue," write the authors of an accompanying editorial. "But will we be putting these women at increased risk of procedures without contributing to their eventual survival?"