Quantitative assessment of background parenchymal enhancement is associated with lifetime breast cancer risk in screening MRI

Ran Yan; Wakana Murakami; Shabnam Mortazavi; Tiffany Yu; Fang-I Chu; Stephanie Lee-Felker; Kyunghyun Sung

doi:10.1007/s00330-024-10758-9

Quantitative assessment of background parenchymal enhancement is associated with lifetime breast cancer risk in screening MRI

Eur Radiol. 2024 Apr 29. doi: 10.1007/s00330-024-10758-9. Online ahead of print.

Authors

Ran Yan^{1

2}, Wakana Murakami^{3

4}, Shabnam Mortazavi³, Tiffany Yu³, Fang-I Chu⁵, Stephanie Lee-Felker³, Kyunghyun Sung^{3

6}

Affiliations

¹ Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA. ranyan@mednet.ucla.edu.
² Department of Bioengineering, Henry Samueli School of Engineering, University of California, Los Angeles, CA, USA. ranyan@mednet.ucla.edu.
³ Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
⁴ Department of Radiology, Showa University Graduate School of Medicine, Tokyo, Japan.
⁵ Department of Radiation Oncology, University of California, Los Angeles, CA, USA.
⁶ Department of Bioengineering, Henry Samueli School of Engineering, University of California, Los Angeles, CA, USA.

PMID: 38683385
DOI: 10.1007/s00330-024-10758-9

Abstract

Objectives: To compare the quantitative background parenchymal enhancement (BPE) in women with different lifetime risks and BRCA mutation status of breast cancer using screening MRI.

Materials and methods: This study included screening MRI of 535 women divided into three groups based on lifetime risk: nonhigh-risk women, high-risk women without BRCA mutation, and BRCA1/2 mutation carriers. Six quantitative BPE measurements, including percent enhancement (PE) and signal enhancement ratio (SER), were calculated on DCE-MRI after segmentation of the whole breast and fibroglandular tissue (FGT). The associations between lifetime risk factors and BPE were analyzed via linear regression analysis. We adjusted for risk factors influencing BPE using propensity score matching (PSM) and compared the BPE between different groups. A two-sided Mann-Whitney U-test was used to compare the BPE with a threshold of 0.1 for multiple testing issue-adjusted p values.

Results: Age, BMI, menopausal status, and FGT level were significantly correlated with quantitative BPE based on the univariate and multivariable linear regression analyses. After adjusting for age, BMI, menopausal status, hormonal treatment history, and FGT level using PSM, significant differences were observed between high-risk non-BRCA and BRCA groups in PE_FGT (11.5 vs. 8.0%, adjusted p = 0.018) and SER_FGT (7.2 vs. 9.3%, adjusted p = 0.066).

Conclusion: Quantitative BPE varies in women with different lifetime breast cancer risks and BRCA mutation status. These differences may be due to the influence of multiple lifetime risk factors. Quantitative BPE differences remained between groups with and without BRCA mutations after adjusting for known risk factors associated with BPE.

Clinical relevance statement: BRCA germline mutations may be associated with quantitative background parenchymal enhancement, excluding the effects of known confounding factors. This finding can provide potential insights into the cancer pathophysiological mechanisms behind lifetime risk models.

Key points: Expanding understanding of breast cancer pathophysiology allows for improved risk stratification and optimized screening protocols. Quantitative BPE is significantly associated with lifetime risk factors and differs between BRCA mutation carriers and noncarriers. This research offers a possible understanding of the physiological mechanisms underlying quantitative BPE and BRCA germline mutations.

Keywords: BRCA germline mutation; Background parenchymal enhancement; Breast cancer; Lifetime risk; Quantitative background parenchymal enhancement.