MRI finds early-stage breast cancers in high-risk women

Magnetic resonance imaging (MRI) scans may help diagnose breast tumors at an early stage in women with the BRCA1 and BRCA2 genes, according to a Canadian study published online March 28 in the Journal of Clinical Oncology.

Investigators from the Women’s College Research Institute in Toronto compared 445 women with BRCA mutations who underwent yearly screening with MRI, mammograms, and breast exams in a doctor’s office or clinic with 830 women with BRCA mutations who were advised to undergo yearly mammograms and clinical breast exams (no formal screening regimen was recommended) as part of a multicenter study. The women ranged in age from 25 to 65 years. During the 6-year study, 9.2% of women in each group developed breast cancer. In the MRI screening group, 14 of every 100 women had early-stage breast cancer compared with 7 of every 100 in the non-MRI group.

“Annual surveillance with MRI is associated with a significant reduction in the incidence of advanced-stage breast cancer in BRCA1 and BRCA2 carriers,” the authors conclude. Only 2 of every 100 women in the MRI group were diagnosed with stage 2 to stage 4 cancer, compared with 7 of 100 in the non-MRI group.

When the researchers considered other risk factors, including age, oral contraceptive use, and whether the women still had their ovaries, they found that women in the MRI group were 70% less likely than women in the non-MRI group to be diagnosed with stage 2 to stage 4 cancer.

The question of whether MRI screening saves lives is still open. The investigators note that further research is needed to examine the effects of screening on death rates from breast cancer. The American Cancer Society recommends both mammography and MRI screening for women with BRCA mutations.