The Relation of Apparent Diffusion Coefficient (ADC) Measurements in Normal Glandular Breast Tissue to Menstrual Cycle & Menopausal State at 3.0T Diffusion-Weighted Imaging.

Elizabeth Anne Maxine O'Flynn¹, Marco Borri¹, Maria Schmidt¹, Veronica Morgan¹, Sharon Giles¹, Catherine Parry-Jones¹, Nandita M. de Souza¹

ADC values during the secretory phase (days 15-28) of the menstrual cycle are known to be slightly higher and less restricted due to the increased water content within the breast. We have demonstrated significant differences in mean ADC values relating to menopausal state, with the ADC value being higher in premenopausal volunteers in the secretory phase (days 15-28) compared to postmenopausal volunteers (p=0.008) due to the effects of increased serum oestradiol and progesterone. This can have implications in the detection of tumours and increased false positives in dynamic contrast-enhanced breast MRI due to the high background parenchymal enhancement.