Clinical radiology 2017 03 1872(7) 552-559 pii S0009-9260(17)30082-X
To evaluate and compare the diagnostic performance of quantitative parameters derived from diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in differentiating benign and malignant bone tumours.
MATERIALS AND METHODS
Fifty-five patients (age range, 21-82 years; mean age, 55 years) underwent pretreatment MRI. Apparent diffusion coefficient (ADC) values were calculated by DWI. The DCE-MRI data were analysed for the volume transfer constant (K(trans)), extravascular extracellular volume fraction (Ve), and volume rate constant (Kep), and K(trans)/ADC ratio. Each parameter’s performance was evaluated using the area under the receiver operating characteristic (ROC) curv (AUC), and their AUCs were compared. ROC curves were analysed and each parameter’s optimal cut-off value was determined, from which each parameter was evaluated for sensitivity, specificity, accuracy, and positive and negative predictive values. The odds ratio (OR) with 95% confidence interval for detecting malignant bone lesions after adjusting the age factor of each parameter was estimated.
All parameter values (except Ve) were significantly different between benign and malignant bone tumours (p<0.05). The K(trans) had a significantly greater AUC than Ve (p=0.03). The K(trans)/ADC and Kep had the best sensitivity (0.917) and specificity (0.632), respectively. The Kep and K(trans)/ADC had the best positive (0.811) and negative (0.769) predictive values, respectively. The OR was highest for K(trans)/ADC (17.38; p=0.0013). CONCLUSION
The K(trans), Kep, ADC, and K(trans)/ADC could help to detect malignant lesions from bone tumours and K(trans)/ADC appears to be the superior variable among them.