(Ivanhoe Newswire) – There are about 2.5 million women in the United States alone who are breast cancer survivors and they face a one in five chance that the cancer will return within ten years of treatment. Now, a large, multicenter study found that the tools used by radiologists to classify breast imaging results is useful in predicting malignancy in breast lesions detected with MRI.
BI-RADS, published by the American College of Radiology in collaboration with other healthcare organizations, is a quality assurance tool used to standardize reporting for breast imaging exams. The system, initially developed for mammography, was expanded in 2003 to include both MRI and ultrasound imaging of the breast.
"BI-RADS was developed to standardize the lexicon of breast imaging reports and to help ensure patients receive proper follow-up," Mary C. Mahoney, M.D, director of breast imaging at the University of Cincinnati Medical Center in Ohio, was quoted as saying. "The BI-RADS lexicon for breast MRI provides descriptors and assessment categories that can be used to help predict the likelihood of cancer."
Radiologists assign breast imaging studies a BI-RADS an assessment of zero to six based on their interpretation of the images and characterization of any lesions present.
The multicenter study was launched to evaluate the performance of BI-RADS for MRI of the breast and to identify the breast imaging features that were most predictive of cancer. Participants in the study included 969 women who had recently received a breast cancer diagnosis in one breast and underwent breast MRI on the other breast at one of 25 participating imaging sites.
Researchers showed that a BI-RADS assessment of 5, defined as highly suggestive of malignancy, and the identification of a mass—a three-dimensional grouping of abnormal cells—were most predictive of cancer.
A BI-RADS score of 5 was assigned to 14 women in the study. Eleven of the 14 women had follow-up imaging, and cancer was identified in 10 of them for a positive predictive value of 71 percent. A BI-RADS score of 4, defined as 'suspicious abnormality, biopsy should be considered,' was assigned to 83 women, 67 of whom had follow-up imaging identifying 17 cancers for a 20 percent positive predictive value.
"MRI is a very important tool in evaluating breast health in women," Dr. Mahoney was quoted saying. "However, there is still wide variability in how the exam is performed and a lack of standardization in test protocols that make it hard to compare results."
She says the recommendation from the multi-study will ultimately help MRI exams more easily transferred from one institution to another.