Intravoxel Incoherent Motion MRI for the Differentiation of Benign, Intermediate, and Malignant Solid Soft-Tissue Tumors

Purpose: To determine the diagnostic potential of apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM)-derived parameters for the differentiation of benign, intermediate, and malignant solid soft-tissue tumors. Materials and Methods: The Institutional Review Board approved this prospective study, and informed consent was obtained. IVIM imaging was performed in 64 patients including 44 benign, 6 intermediate, and 14 malignant solid soft-tissue tumors at 1.5T. The IVIM parameters of the soft-tissue tumors were assessed using the Kruskal-Wallis test. The diagnostic performance of the parameters was evaluated using receiver operating characteristic (ROC) analysis. Results: The ADC and true diffusion coefficient (D) values of malignancies (1.280.31, 1.060.23 [x10(-3) mm(2)/sec]) were significantly lower than those of intermediate (1.490.54, 1.300.50 [x10(-3) mm(2)/sec]), or benign soft-tissue tumors (1.62 +/- 0.37, 1.36 +/- 0.33 [x10(-3) mm(2)/sec]) (P=0.007 and P=0.009, respectively). In the differential diagnosis of malignancies from benign tumors, ADC demonstrated the highest area under the curve (Az) value (Az=0.793). The perfusion fraction (f) values of intermediate soft-tissue tumors (8.41 +/- 2.73) were significantly different from those of benign and malignant tumors (14.70 +/- 5.37 [P=0.002]; 14.44 +/- 5.31 [P=0.021]). f showed the highest Az value in differentiating intermediate from benign, and malignant soft-tissue tumors (Az=0.90, and Az=0.833, respectively). The pseudodiffusion coefficient (D*) values of malignant soft-tissue tumors (144.40 +/- 24.88 [x10(-3) mm(2)/sec]) were significantly higher than those of benign tumors (124.96 +/- 26.24 [x10(-3) mm(2)/sec]) (P=0.019). Conclusion: IVIM imaging may be helpful for differentiating benign, intermediate, and malignant solid soft-tissue tumors.