Diffusion weighted imaging of the normal breast: reproducibility of apparent diffusion coefficient measurements and variation with menstrual cycle and menopausal status
- 542 Downloads
To establish the reproducibility of apparent diffusion coefficient (ADC) measurements in normal fibroglandular breast tissue and to assess variation in ADC values with phase of the menstrual cycle and menopausal status.
Thirty-one volunteers (13 premenopausal, 18 postmenopausal) underwent magnetic resonance twice (interval 11–22 days) using diffusion-weighted MRI. ADCtotal and a perfusion-insensitive ADChigh (omitting b = 0) were calculated. Reproducibility and inter-observer variability of mean ADC values were assessed. The difference in mean ADC values between the two phases of the menstrual cycle and the postmenopausal breast were evaluated.
ADCtotal and ADChigh showed good reproducibility (r% = 17.6, 22.4). ADChigh showed very good inter-observer agreement (kappa = 0.83). The intraclass correlation coefficients (ICC) were 0.93 and 0.91. Mean ADC values were significantly lower in the postmenopausal breast (ADCtotal 1.46 ± 0.3 × 10-3 mm2/s, ADChigh 1.33 ± 0.3 × 10-3 mm2/s) compared with the premenopausal breast (ADCtotal 1.84 ± 0.26 × 10-3 mm2/s, ADChigh 1.77 ± 0.26 × 10-3 mm2/s; both P < 0.001). No significant difference was seen in ADC values in relation to menstrual cycle (ADCtotal P = 0.2, ADChigh P = 0.24) or between postmenopausal women taking or not taking oestrogen supplements (ADCtotal P = 0.6, ADChigh P = 0.46).
ADC values in fibroglandular breast tissue are reproducible. Lower ADC values within the postmenopausal breast may reduce diffusion-weighted contrast and have implications for accurately detecting tumours.
• ADC values from fibroglandular breast tissue are measured reproducibly by multiple observers.
• Mean ADC values were significantly lower in postmenopausal than premenopausal breast tissue.
• Mean ADC values did not vary significantly with menstrual cycle.
• Low postmenopausal ADC values may hinder tumour detection on DW-MRI.
KeywordsDiffusion-weighted MRI Apparent diffusion coefficient Fibroglandular Breast
We would like to acknowledge the generous help of all of the volunteers for offering their time. We would also like to acknowledge Catherine Simpkin for her help with data acquisition and Maria Schmidt and Marco Borri for their support in setting up the imaging protocol. We would like to acknowledge the advice of David Collins during preparation of the manuscript and Rosy Grant for her secretarial assistance.
We acknowledge the support received from the CRUK and EPSRC Cancer Imaging Centre in association with the MRC and Department of Health (England) grant C1060/A10334, and NHS funding to the NIHR Biomedical Research Centre.
- 15.Rosen PP (2001) Anatomy and physiologic morphology. Rosen's breast pathology, 3rd edn. Lippincott Williams and Williams, Philadelphia, pp 1–21Google Scholar
- 22.Le BD, Breton E, Lallemand D, Aubin ML, Vignaud J, Laval-Jeantet M (1988) Separation of diffusion and perfusion in intravoxel incoherent motion MR imaging. Radiology 168:497–505Google Scholar
- 25.Bito T, Hirata S, Yamamoto E (1995) Optimal gradient factors for ADC measurements. Proceedings of the 3rd Annual Meeting of the ISMRM, p 913Google Scholar