Enhancement parameters on dynamic contrast enhanced breast MRI: do they correlate with prognostic factors and subtypes of breast cancers?

Objective: To correlate the enhancement parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with prognostic factors and immunohistochemical subtypes of breast cancer. Material and Methods: A total of 81 breast carcinomas were included in our study. We obtained the following enhancement parameters: 1) analysis of background parenchymal enhancement (BPE) and BPE coefficients (BEC) from bilateral breasts, 2) the number of vessels per breast as a representation of ipsilateral whole-breast vascularity. Additionally, in 50 patients, 3) semiquantitative parameters of tumors (the initial enhancement percentage (E-1), the peak enhancement percentage (E-peak), the time to peak enhancement (TTP), the signal enhancement ratio (SER)) and 4) perfilsion parameters (K-trans, k(ep), v(e) and (j)AUC) from tumors and ipsilateral breasts were also obtained. Correlations among parameters and prognostic factors, including tumor size, axillaiy node status, nuclear grade, histologic grade, estrogen receptor (ER) expression, progesterone receptor (PR) expression, Ki-67, human epidermal growth factor receptor 2 (HER-2) expression, epidermal growth factor receptor (EGFR) expression, bcl-2, CK5/6 and subtypes categorized as luminal (ER or PR positive), triple negative (ER or PR negative, HER-2 negative) and HER2 (ER and PR negative with HER-2 overexpression) were analyzed. Results: BPE was significantly correlated with EGFR expression (p = 0.040). BEC was significantly higher in tumors larger than 2 cm than in tumors smaller than 2 cm (p = 0.001). The vessel numbers in ipsilateral breasts were higher in tumors larger than 2 cm than in tumors smaller than 2 cm (p = 0.034), with higher nuclear grades (grade 3) than with lower nuclear grades (grade 1,2) (p = 0.001) and with PR-negative rather than with PR-positive (p = 0.010) results. The mean K-trans was higher in Ki-67-positive tumors than Ki-67 negative tumors (P = 0.002). The mean k(ep) was higher in 10-67-positive tumors than in Ki-67-negative tumors (p = 0.005) and in CK5/6-positive tumors than in CK5/6-negative tumors (p = 0.015). The mean K-trans was lower in the ipsilateral breast parenchyma with HER-2-positive tumors compared to HER-2-negative tumors (p = 0.012). Conclusion: BPE, BEC and ipsilateral whole-breast vascularity, higher K-trans and k(ep) of the cancer and lower K-trans and (j)ADC of ipsilateral breast parenchyma may serve as additional predictors of a poor breast cancer prognosis. (C) 2014 Elsevier Inc. All rights reserved.