Report from ARRS: Survey highlights trends in breast MRI practice

Most U.S. breast specialists are performing contrast-enhanced breast MRI, albeit at a fairly low volume, according to a survey presented today at the American Roentgen Ray Society meeting in Orlando. About one-third of facilities performing breast MRI do not offer MRI-guided biopsies as well, however.

The web survey, administered by researchers at the University of California, Los Angeles and Memorial Sloan-Kettering Cancer Center in New York City, polled 1305 members of the Society of Breast Imaging and received responses to its 25 questions from 629 of them. Results show that 75% of respondents are performing CE-MRI in the breast, though about two-thirds said scan volume was lower than 10 breast MR scans per week.

"The American College of Radiology is in the process of developing practice guidelines for breast MRI. These results should be useful for that. This information will also be useful for radiologists who want to establish a breast MRI program or improve an existing one," said presenter Dr. Sonia Dhaliwal, a radiologist at UCLA.

Typically, breast MRI is performed by radiologists who are certified under the Mammography Quality Standards Act. In some cases, however, studies are read by radiologists who specialize in MRI.

Respondents said they rarely or never interpret breast MRI without correlating mammography and breast ultrasound images. Unexpected findings on breast MRI are most often followed with a second-look ultrasound. Nearly half of those doing breast MRI read the studies on soft-copy workstations equipped with computer-aided detection.

Frequent indications for diagnostic breast MRI include evaluation of extent of disease, assessment of patients after an abnormal screening mammogram with equivocal diagnostic workup, monitoring of response to chemotherapy, and provision of information in cases of cancer with an unknown primary. It is extremely rare (7%) for radiologists to perform breast MRI without first doing a conventional workup.

Of those SBI members who are performing breast MRI, 64% were doing the study for screening purposes. The most common indications are assessment of women who are BRCA-positive or whose mother or sister had breast cancer and those with a personal history of breast cancer. A small number of facilities perform screening MRI for women with silicone implants, according to the survey.