Table 2.

Studies evaluating association of quantitative BPE features with breast cancer risk

	Study Design	Patient Population	Endpoint	BPE parameters	Findings
Wu, et al., 2015 (70)	Retrospective cohort	BRCA1/2 mutation carriers who underwent RRSO	Risk of future breast cancer diagnosis	Absolute and relative whole breast volumes of BPE above a predefined enhancement threshold	Decreased BPE measurements after RRSO associated with no cancer development. Increased BPE post-RRSO associated with cancer development.
Hu, et al, 2017 (67)	Retrospective cohort (malignant, benign, negative)	Not disclosed	Risk of breast cancer diagnosis at time of MRI	Ratio of whole breast volume of BPE to total FGT at varying thresholds	Increased BPE associated with cancer development.
Lam, et al., 2018 (58)	Retrospective case control, 23 cancers matched 1:1 to no cancer control	High risk screening	Risk of either cancer diagnosis at time of MRI or in future	Variable thresholds of percent enhancement for each voxel within 2D area of FGT	Greater BPE area and increased intensity parameters associated with cancer development.

BPE = background parenchymal enhancement, RRSO = risk-reducing salpingo-oopherectomy, FGT = fibroglandular tissue