MRI Technique May Reduce Need for Breast Biopsies

Unenhanced diagnostic MR imaging–DWIBS mammography may detect false-positive X-ray screening mammograms.

Unenhanced diagnostic MR imaging (DWIBS mammography) may reduce the number of breast biopsies performed on women with suspicious X-ray screening mammograms, according to a study published in Radiology.

Researchers from Germany evaluated the ability of DWIBS mammography and unenhanced morphologic sequences to predict the likelihood of malignancy on suspicious screening X-ray mammograms, as compared with an abbreviated contrast material–enhanced breast MR imaging protocol and a full diagnostic breast MR imaging protocol. Unenhanced diagnostic MR imaging–DWIBS mammographies are shorter examinations (can be less than seven minutes) than full breast MR imaging protocol, which can take up to a half hour.[[{"type":"media","view_mode":"media_crop","fid":"42660","attributes":{"alt":"Sebastian Bickelhaupt, MD","class":"media-image media-image-right","id":"media_crop_7000558780930","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"4640","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"height: 266px; width: 200px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"Sebastian Bickelhaupt, MD","typeof":"foaf:Image"}}]]

Fifty women (mean age, 57.1) participated in the prospective study. All had undergone mammograms, which showed suspicious findings, leading to recommendations for biopsies. Before having the biopsies, the women underwent full diagnostic contrast-enhanced MR imaging, which included DWIBS mammography. Two abbreviated protocols (APs) based on maximum intensity projections (MIPs) were evaluated regarding the potential to exclude malignancy: DWIBS (AP1) and subtraction images from the first postcontrast and the unenhanced series (AP2).

The results showed that 24 of the 50 women had a breast carcinoma:

 AP1 protocolAP2 protocol
Sensitivity0.92 (95% CI: 0.73, 0.98)0.85 (95% CI: 0.78, 0.95)
Specificity0.94 (95% CI: 0.77, 0.99)0.90 (95% CI: 0.72, 0.97)
Negative predictive value0.92 (95% CI: 0.75, 0.99)0.87 (95% CI: 0.69, 0.95)
Positive predictive value0.93 (95% CI: 0.75,0.99)0.89 (95% CI: 0.69, 0.97)
Mean reading time29.7 seconds (range, 4.9–110.0 seconds)29.6 seconds (range, 6.0–100.0 seconds)

Only pure microcalcification related ductal carcinoma in-situ (DCIS) without solid tumor, a very early stage of breast cancer, was not detected by any of the MR techniques.

“If the preliminary findings are confirmed, this approach could have a high potential to be used as an adjunct in the clarification process of unclear lesions on X-ray mammography in breast cancer screening,” lead author Sebastian Bickelhaupt, MD, said in a release. “This might help to reduce the number of invasive biopsies and the related anxiety in women who have suspicious findings at mammography.”

Bickelhaupt noted that more research is needed: “While the results so far are promising, the degree of evidence is currently not sufficient to recommend the method be implemented into the screening in a general setting.”