Increased background parenchymal enhancement on screening MRI associated with higher risk of breast cancer

High-risk patients with any amount of background parenchymal enhancement (BPE) beyond the minimum on screening MRI have an increased risk of developing breast cancer, according to a new study published by Academic Radiology.

“The association between increased breast density on mammography and future breast cancer is well established, but the corresponding relationship between BPE on MRI and breast cancer risk is less well known,” wrote lead author Lars J. Grimm, MD, MHS, department of radiology at Duke University Medical Center in Durham, North Carolina, and colleagues. “Use of computer vision algorithms to quantify various BPE metrics have had mixed results in predicting future breast cancer, in part because of different methods of quantifying BPE.”

The authors studied data from screening breast MRIs performed at a single institution from August 2004 to July 2013. Five breast radiologists then independently examined the MRIs of 61 high-risk patients who went on to develop breast cancer, recording the BPE of each patient. The BPE was significantly higher in the 61 high-risk patients than in the study’s control cohort.

“Women with mild, moderate or marked BPE were 2.5 times more likely to develop breast cancer than women with minimal BPE,” Grimm and colleagues wrote.

The authors noted that increased BPE was associated with a higher risk of breast cancer by three of the study’s five readers. That association was “borderline” for one of the other two readers and “non-significant” for the other.

“Further work to objectively quantify the BPE and thus reduce reader interobserver variability as well as subsequent validation of these findings in larger multi-institution datasets and among specific patient subgroups could be beneficial to women undergoing high-risk screening with breast MRI,” the authors concluded.