What background parenchymal enhancement levels mean for high-risk, average-risk women

High levels of background parenchymal enhancement (BPE) on breast MRI scans are associated with a greater chance of breast cancer in high-risk women, according to a new meta-analysis published in Radiology. This is not true, however, for women at an average risk.

“As an emerging screening and diagnostic measure, it is thought that BPE may make a substantial contribution as a tool for improving early detection and prevention of breast cancer, as well as for identifying the population at risk for developing breast cancer,” wrote Christopher M. Thompson, Texas Tech University Health Sciences Center El Paso, and colleagues. “However, its integration into routine clinical care is still debated, mainly due to inconsistent associations with breast cancer. We sought to conduct a systematic review and meta-analysis to test whether higher levels of BPE are associated with higher odds of breast cancer.”

The authors selected and explored 18 studies. Two authors with experience in statistical analysis independently took part in the selection process. All studies were originally published in English, conducted on humans and included BPE measurements of both breast cancer patients and patients without breast cancer.

Overall, the 18 studies included nearly 2,000 women with breast cancer and more than 2,500 women control participants. For high-risk patients, at least moderate BPE or at least mild BPE were associated with higher odds of the patient having breast cancer. At least moderate BPE or at least mild BPE were not associated with such odds for patients at an average risk.

In addition, women with breast cancer did display higher BPE percentages than high-risk control participants.

“Our meta-analysis does not confirm a significant association between a higher level of BPE and the presence of breast cancer among women with average risk,” Thompson et al. concluded. “We suggest incorporating a standardized protocol for BPE measurement that follows a uniform format for recording BPE data, preferably in a quantitative form. This incorporation may improve the reliability and interpretation of BPE data. A large multicenter longitudinal study is warranted to confirm the association of higher BPE values measured by using breast MRI and changes in BPE values for predicting the risk of developing breast cancer.”