In Vivo Conductivity of Normal Fibroglandular Tissue Using MR Electrical Properties Tomography: A Comparison With Apparent Diffusion Coefficient

Abstract

Purpose: This study aims to evaluate the conductivity of normal breast parenchyma according to the menstrual cycle or menopausal status compared with the apparent diffusion coefficient (ADC), and to determine whether the conductivity of normal breast parenchyma is affected by other clinicopathological variables in patients with breast cancer. Materials and Methods: This study included 100 patients with breast cancer who had information available regarding menstruation and underwent breast magnetic resonance imaging (MRI) for preoperative evaluation of breast cancer between July 2013 and December 2017. The conductivity and ADCs of contralateral normal glandular tissue were measured and compared according to menopausal status (premenopausal vs. postmenopausal women) and menstrual cycle (weeks 1 to 4). Results: Unlike parenchymal enhancement, which differed depending on menopausal status, no significant differences were observed in ADCs and conductivity of contralateral normal glandular tissue between premenopausal and postmenopausal women (p = 0.510, p = 0.076, respectively) or among the four menstrual weeks in premenopausal women (p = 0.502, p = 0.767, respectively). In multivariate analysis, mammographic density was an independent factor associated with ADC and conductivity of the contralateral normal breast parenchyma (p = 0.001). Conclusion: There were no significant differences in ADCs and conductivity of the contralateral normal breast parenchyma based on menopausal status and menstrual cycle, suggesting that MRI can be performed at any time, regardless of the menstrual cycle. ADC and conductivity of normal breast parenchyma were not affected by clinicopathological factors other than breast density.