Breast MRI is the study of choice for women at high risk for breast cancer.

According to a study published in Radiology Lo et al reviewed the outcomes of 3,934 screening breast studies (MRI and mammograms) performed on 1,249 high-risk women. A total of 45 cancers (33 invasive and 12 ductal carcinomas in situ) were diagnosed, 43 were seen with MR imaging and 14 with both mammography and MR imaging.   The cancer detection rate for MR imaging was 21.8 cancers per 1000 examinations and that for mammography was 7.2 cancers per 1000 examinations. Sensitivity and specificity of MR imaging were 96% and 78% respectively, and those of mammography were 31% and 89%, respectively (P < .001).  The researchers reported that all cancers found at screening mammography were also detected on breast MRI.  

The researchers concluded that annual screening mammography adds no value to women that are at high risk for breast cancer especially since they are screened each year with breast MRI.

MRI Scans May Predict A Woman’s Future Risk Of Developing Breast Cancer

Research by Dontchos et al published in Radiology suggests that MRI of the breast may predict a woman’s future risk of developing breast cancer.  They looked whether qualitative magnetic resonance imaging (MRI) assessments of background parenchymal enhancement (BPE), amount of fibroglandular tissue (FGT), and mammographic density are associated with risk of developing breast cancer in women who are at high risk.

They reviewed all screening breast MRI studies obtained from January 2006 to December 2011 in women aged 18 years or older and at high risk for but without a history of breast cancer. Women in whom breast cancer was diagnosed after index MR imaging comprised the cancer cohort, and one-to-one matching (age and BRCA status) of each woman with breast cancer to a control subject was performed by using MR images obtained in women who did not develop breast cancer with follow-up time maximized. Amount of BPE, BPE pattern (peripheral vs central), amount of FGT at MR imaging, and mammographic density were assessed on index images.

Twenty-three women at high risk (mean age, 47 years ± 10 [standard deviation]; six women had BRCA mutations with no history of breast cancer underwent screening breast MR imaging; in these women, a diagnosis of breast cancer (invasive, n = 12; in situ, n = 11) was made during the follow-up interval. Women with mild, moderate, or marked BPE were nine times more likely to receive a diagnosis of breast cancer during the follow-up interval than were those with minimal BPE. BPE pattern, MR amount of FGT on MRI, and mammographic density were not significantly different between the cohorts.

Greater background parenchymal enhancement (BPE) was associated with a higher probability of developing breast cancer in women at high risk for cancer and warrants further study.