Increased background parenchymal enhancement level a key biomarker for breast cancer risk

Increased background parenchymal enhancement (BPE) levels at breast MRI are associated with a greater risk of developing breast cancer within a year, according to new findings published in the American Journal of Roentgenology.

“Identifying patients with hormonally responsive breast tissue has important clinical implications,” wrote Dorothy A. Sippo, MD, department of radiology at Massachusetts General Hospital in Boston, and colleagues. “Combining physiologic BPE information gained from contrast-enhanced MRI with specific clinical risk factors has the potential to offer more tailored treatment and prevention strategies, such as designing patient-specific screening regimens, chemo-prevention strategies, management of high-risk breast lesions, and aiding in complex decisions regarding prophylactic mastectomies.”

The authors explored data from more than 4,600 breast MRI examinations performed on more than 2,400 women between 2011 and 2014. While 85 percent of the cohort had minimal or mild BPE, 15 percent had moderate or marked BPE. Twelve percent of the patients were a BRCA carrier or had a history of thoracic radiation. In addition, 54 percent of patients had a personal history of breast cancer and 26 percent had a family history of breast cancer.

Overall, BPE and a high-risk screening indication were found to be independent predictors of a breast cancer diagnosis.

“The multivariable model we used adjusted for multiple possible confounding breast cancer risk factors, including age, mammographic breast density, and screening indication,” the authors wrote. “Our work confirms that, even accounting for these confounders, BPE remains an independent predictor of breast cancer in high-risk patients undergoing screening MRI.”

Sippo and colleagues also looked for a “possible interaction” between BPE and the patient’s screening indication, but “did not find this to be significant.”

“This finding suggests that the effect of BPE is similar across different high-risk populations,” the authors wrote.

Noting that BPE “appears to be an important biomarker for future breast cancer risk,” the researchers observed that the measurement can also help women make important decisions about chemoprevention therapy.