Contrast enhancement kinetics of normal breast parenchyma in dynamic MR mammography: Effects of menopausal status, oral contraceptives, and postmenopausal hormone therapy

摘要

Objectives: To investigate effects of menopausal status, oral contraceptives (OC), and postmenopausal hormone therapy (HT) on normal breast parenchymal contrast enhancement (CE) and non-mass-like enhancing areas in magnetic resonance mammography (MRM). Methods: A total of 459 female volunteers (mean age 49.1± 12.5 years) underwent T1-weighted 3D MRM 1-5 min after bolus injection of gadobutrol. Quantitative analysis was performed in normal breast parenchyma by manually tracing regions of interest and calculating percentage CE. Semiquantitative analysis was performed in non-mass-like enhancing areas, and signal intensity changes were characterised by five predefined kinetic curve types. The influence ofOC(n=69) and HT (n=24) on CE was studied using random effects models. Results: Breast parenchymal enhancement was significantly higher in premenopausal than in postmenopausal women (P<0.001). CE decreased significantly with the use of OC (P=0.01), while HT had negligible effects (P=0.52). Prevalence of kinetic curve types of non-mass-like enhancement differed strongly between pre- and postmenopausal women (P<0.0001), but was similar in OC users and non-OC users (P=0.61) as well as HT users and non-HT users (P=0.77). Conclusions: Normal breast parenchymal enhancement and non-mass-like enhancing areas were strongly affected by menopausal status, while they were not affected by HT use and only moderately by OC use. Key Points: ? Breast parenchymal enhancement at MR mammography is stronger in premenopausal than postmenopausal women. ? The prevalence of strong enhancing non-mass-like areas is greater before menopause. ? Such enhancing non-mass-like areas may impair lesion detection in premenopausal women. ?Breast parenchymal enhancement is only marginally affected by hormone use. ? Discontinuation of hormone use before MR mammography may be unnecessary.