QUANTITATIVE CORRELATION OF BREAST-TISSUE PARAMETERS USING MAGNETIC-RESONANCE AND X-RAY MAMMOGRAPHY

Previous investigators have shown that there is a strong association b etween the fraction of fibroglandular tissue within the breast as dete rmined by X-ray mammography (per cent density) and breast cancer risk. In this study, the quantitative correlation between per cent density and two objective magnetic resonance (MR) parameters of breast tissue, relative water content and mean T2 relaxation time, as investigated f or 42 asymptomatic subjects. Using newly developed, rapid techniques M R measurements were performed on a volume-of-interest incorporating eq ual, representative portions of both breasts. X-ray mammograms of each subject were digitised and analysed semiautomatically to determine pe r cent density. Relative water content showed a strong positive correl ation with per cent density (Pearson correlation coefficient r(p) = 0. 79, P < 0.0001) and mean T2 value showed a strong negative correlation with per cent density (r(p) = -0.61, P < 0.0001). The MR and X-ray pa rameters were also associated with sociodemographic and anthropometric risk factors for breast cancer (P < 0.05). The potential use of MR pa rameters to assess risk of breast cancer and to provide a frequent, no n-hazardous monitor of breast parenchyma is discussed.