Table 4.

Studies evaluating association of quantitative BPE parameters with breast cancer treatment outcomes

	Study Design	Patient Population	Endpoint	BPE parameters	Findings
Chen, et al., 2015 (66)	Retrospective cohort, 46 patients underwent pre-treatment MRI and two follow-up MRI exams	IBC undergoing NAC	pCR	Average % increase in bilateral BPE signal intensity over 12 post-contrast sequences	Decrease in BPE correlated with pCR in patients with ER− tumors
van der Velden, et al., 2015 (65)	Retrospective cohort, 531 patients	Unilateral IBC	Overall survival and invasive DFS	Late phase mean top 10% enhancement in contralateral breast	Increased BPE associated with better overall survival for ER+, HER2− tumor subtypes, especially for those who underwent endocrine therapy
You, et al, 2017 (96)	Retrospective cohort, 90 patients underwent baseline MRI and MRI after 2nd, 4th, and 6th cycles of NAC	Unilateral IBC and DCIS	Tumor size pCR	Ratio of enhanced FGT volume to total FGT volume and mean BPE of the 4 times points (k0= 90, 180, 270, and 360s) in contralateral breast	BPE and changes of BPE at each monitoring point associated with tumor size
Luo, et al., 2017 (99)	Retrospective case control, 11 cases with recurrence matched (1:1) to cases without recurrence	Unilateral DCIS	Ipsilateral breast cancer recurrence > 6 months after definitive surgery	Ipsilateral BPE using a 10% threshold on first post-contrast series (k0= 90–120s)	Patients with DCIS recurrence more likely to have greater mean BPE

BPE = background parenchymal enhancement, IBC = invasive breast cancer, NAC = neoadjuvant chemotherapy, pCR = pathologic complete response, ER = estrogen receptor, DFS = disease-free survival, HER2 = human epidermal growth factor receptor 2, RFS=recurrence free survival, PD = progressive disease, PR = progesterone receptor, LVI = lymphovascular invasion, DCIS = ductal carcinoma in situ, FGT=fibroglandular tissue, MIP = maximum intensity projection