MRI Breast Cancer Screening In High-Risk Women Boosts Detection Rates

Using MRI to screen women with a history of lobular carcinoma in situ (LCIS) improved the rate of cancer detection, a pair of new studies show.

MRI shows known breast cancer on the left side of the image. The left breast (right side of the image) reveals a small occult cancer that was not clinically apparent or visible on the screening mammogram. (Image courtesy University of Washington Breast Center)

LCIS is a non-invasive breast cancer that requires no immediate or active treatment, according to the American Cancer Society; however having LCIS increases the risk that these women will later develop a malignant tumor. Consequently these women are closely followed with yearly mammograms and a clinical breast exams.


Adding magnetic resonance imaging (MRI) to screen for
breast cancer is controversial. A 2007 European review of
MRI with mammography for high-risk women found that
MRI improved sensitivity to as high as 94 percent, but specificity with MRI was less consistent with a 3-5-fold
higher risk of patient recall for false positive results. (Link to published site)


Consequently, the American Cancer Society does not recommend routine screening MRI for breast cancer, but
does suggest that MRI in addition to mammograms is reasonable for women with LCIS.


Dr. Janice Sung and colleagues from the Departments of Radiology and Breast Imaging at Memorial Sloan-Kettering
in New York say there is little evidence to support MRI screening in women with a history of LCIS.


“To our knowledge, there has been only one published study in which researchers evaluated the utility of screening breast MR imaging in women with LCIS,” the authors wrote.
Sung and colleagues conducted a retrospective study examining the data from 670 screening MRIs conducted at their institution in 220 women with a history of LCIS between 2003 and 2008, and compared the cancer detection rates with the screening mammograms done in these women.

In the study led by Dr. Lauren Friedlander of the Department of Radiology at the Columbia Presbyterian Medical Center, New York, the researchers drew from 445 breast MRI exams from their institution’s database between 1996 and 2009.

The purpose of both studies was to assess the effectiveness of screening MRI in the detection of otherwise hidden cancer in women with a history of LCIS. Both studies were published Sept. 7 online ahead of print in the journal Radiology.

In Sung’s study, out of 670 MRI screening studies conducted, 63 lesions were seen in 58 MRIs (9 percent) and recommended for biopsy. Another eight lesions were identified after a short-term follow-up to the first MRI for a total of 71 lesions found in 59 patients recommended for biopsy. Of a total of 60 biopsies taken, 12 cancers (20 percent) were identified. An additional 26 lesions were identified by mammography, 25 were biopsied, and five of them (20 percent) were identified as cancer.

Overall 17 cancers were detected in 14 patients during the study period. Of these, 12 (70.5 percent) were detected with MRI imaging alone compared to five (29 percent) detected by mammography alone. Of the 12 cancers detected at MR imaging, there were nine invasive cancers and three cases of ductal carcinoma in situ (DCIS). For those detected with mammography alone, two were invasive and three were DCIS.

In Friedlander’s study, out of the 445 MR examinations in 198 patients with LCIS they found 308 that were screening examinations in 134 patients, and one of those was excluded for being a carrier of a BRCA mutation. Of the remaining 307 MRIs, 254 (82.7 percent) were BI-RADS category 1 or 2. Another 27 (8.8 percent) were BI-RADS category 3, and 27 more (8.8 percent) were BI-RADS category 4 or 5.

Of the 27 studies that were recommended for biopsy, 10 (37 percent) were found to be benign by pathologic exam, five (18.5 percent) were found to be malignant, and seven (25.9 percent) were found to be high-risk lesions. Of the 27 studies with BI-RADS 3 findings, two (7.4 percent) resulted in biopsy, with both found to be benign.

Overall, malignancy was detected in five of 307 screening studies (1.6 percent) and in five of 133 screened patients (3.8 percent). For the screening studies for which biopsy was recommended the positive predictive value (PPV) was 18.5 percent. For those MRI studies that were recommended and performed, the PPV was 23.8 percent.

Friedlander’s group concluded that screening breast MR imaging helped identify breast cancer in LCIS patients at a rate similar to that shown in high-risk populations for whom screening breast MR imaging is currently consistently recommended.

Sung’s group concluded that adding MRI screening in women with a history of LCIS is an effective addition for cancer detection. “MR imaging is a useful adjunct modality with which to screen women with a history of LCIS at high-risk of developing breast cancer, resulting in a 4.5 percent incremental cancer detection rate,” they concluded. “Sensitivity in the detection of breast cancers with a combination of MR imaging and mammography was higher than sensitivity of either modality alone.”

By Michael O’Leary, contributing writer, Health Imaging Hub