Combined reading of Contrast Enhanced and Diffusion Weighted Magnetic Resonance Imaging by using a simple sum score

To improve specificity of breast MRI by integrating Apparent Diffusion Coefficient (ADC) values with contrast enhanced MRI (CE-MRI) using a simple sum score. Retrospective analysis of a consecutive series of patients referred to breast MRI at 1.5 T for further workup of breast lesions. Reading results of CE-MRI were dichotomized into score 1 (suspicious) or 0 (benign). Lesion's ADC-values (in *10-3 mm2/s) were assigned two different scores: ADC(2): likely malignant (score +1, ADC a parts per thousand currency signaEuro parts per thousand 1), indeterminate (score 0, ADC > 1- a parts per thousand currency signaEuro parts per thousand 1.4) and likely benign (score -1, ADC > 1.4) and ADC(1): indeterminate (score 0, ADC a parts per thousand currency signaEuro parts per thousand 1.4) and likely benign (score -1, ADC > 1.4). Final added CE-MRI and ADC scores > 0 were considered suspicious. Reference standard was histology and imaging follow-up of > 24 months. Diagnostic parameters were compared using McNemar tests. A total of 150 lesions (73 malignant) were investigated. Reading of CE-MRI showed a sensitivity of 100 % (73/73) and a specificity of 81.8 % (63/77). Additional integration of ADC scores increased specificity (ADC2/ADC1, P = 0.008/0.001) without causing false negative results. Using a simple sum score, ADC-values can be integrated with CE-MRI of the breast, improving specificity. The best approach is using one threshold to exclude cancer. aEuro cent ADC is used to assign levels of suspicion to breast lesions. aEuro cent ADC values > 1.4 *10 (-3) mm (2) /s are likely benign and effectively rule out malignancy. aEuro cent ADC values below a parts per thousand currency sign1*10 (-3) mm (2) /s) are likely malignant but may be false positive. aEuro cent CE-MRI (+1: suspicious, 0: benign) and ADC (0: indeterminate, -1: benign) scores are added. aEuro cent Sum scores > 0 should be biopsied.