Diffusion-weighted and Dynamic Contrast-enhanced MRI of Metastatic Bone Tumors: Correlation of the Apparent Diffusion Coefficient, K(trans) and ve values

ABSTRACT

PURPOSE: To investigate whether quantitative parameters derived from Diffusion-weighted magnetic resonance imaging (DW-MRI) correlate with those of Dynamic contrast-enhanced MRI (DCE-MRI). MATERIALS AND METHODS: Thirteen patients with pathologically or clinically proven bony metastasis who had undergone MRI prior to treatment were included. The voxel size was 1.367 x 1.367 x 5 mm. A dominant tumor was selected and the apparent diffusion coefficient (ADC) value and DCE-MRI parameters were obtained by matching voxels. DCE-MRI data were analyzed yielding estimates of K(trans) (volume transfer constant) and ve. (extravascular extracellular volume fraction). Statistical analysis of ADC, K(trans), and ve value was conducted using Pearson correlation analyses. RESULTS: Fifteen lesions in pelvic bones were evaluated. Of these, 11 showed a statistically significant correlation (P < 0.05) between ADC and K(trans). The ADC and K(trans) were inversely related in 7 lesions and positively related in 4 lesions. This did not depend on the primary cancer or site of metastasis. The ADC and ve of 9 lesions correlated significantly. Of these, 4 lesions were inversely related and 5 lesions were positively related. CONCLUSION: Unlike our theoretic hypothesis, there was no consistent correlation between ADC values and K(trans) or between ADC values and ve in metastatic bone tumors.