Multicentric Cancer on Breast MRI Likely Clinically Relevant

Breast imaging with MRI may detect additional invasive cancers, according to a study published in Radiology.

Researchers from Italy and the United States performed a retrospective study to review the use of MRI and pathologic features of multicentric cancer detected only at MR imaging and to evaluate its potential biologic value.

The researchers reviewed records of 2,021 patients who had been newly diagnosed with breast cancer and who underwent biopsy after preoperative MR imaging. In this group, 285 patients (14%) had additional cancer detected at MR imaging that was occult at mammography. Seventy-three patients (3.6%) had 87 cancers identified by MRI in different quadrants than the known index cancer, which was the basis of this report. Of these 73 patients, 62 patients (85%) were found to have one additional cancer and 11 patients (15%) were found to have multiple additional cancers.

The results showed that known index cancers were more likely to be invasive than MRI–detected multicentric cancers (88% versus 76%, respectively). Other findings included:[[{"type":"media","view_mode":"media_crop","fid":"48519","attributes":{"alt":"breast MRI","class":"media-image media-image-right","id":"media_crop_7183616927001","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"5791","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: 128px; width: 171px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"©RSNA 2015","typeof":"foaf:Image"}}]]

• 21 of 87 lesions (24%) ductal carcinoma in situ were a minority of additional MR imaging–detected multicentric cancers

• Median size of MRI–detected multicentric invasive cancers was smaller than that of the index cancer (0.6 cm versus 1.2 cm, respectively)

• 17 of 73 patients (23%) had larger MRI–detected multicentric cancers than the known index lesion

• 18 of 73 patients (25%) had MRI–detected multicentric cancers larger than 1 cm

• MRI–detected multicentric cancers and index cancers differed in histologic characteristics, invasiveness, and grade in 27 of 73 patients (37%)

• MRI–detected multicentric cancers were potentially more biologically relevant because of the presence of unsuspected invasion or a higher grade n four of 73 patients (5%)

“An unsuspected additional multicentric cancer seen only at MR imaging is likely clinically relevant disease,” the researchers concluded.