Intravoxel incoherent motion MRI for the differentiation of benign, intermediate, and malignant solid soft-tissue tumors

Abstract

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 (1.28 ± 0.31, 1.06 ± 0.23 [×10−3 mm2/sec]) were significantly lower than those of intermediate (1.49 ± 0.54, 1.30 ± 0.50 [×10−3 mm2/sec]), or benign soft-tissue tumors (1.62 ± 0.37, 1.36 ± 0.33 [×10−3 mm2/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 [×10−3 mm2/sec]) were significantly higher than those of benign tumors (124.96 ± 26.24 [×10−3 mm2/sec]) (P = 0.019). Conclusion: IVIM imaging may be helpful for differentiating benign, intermediate, and malignant solid soft-tissue tumors. Level of Evidence: 1. Technical Efficacy: Stage 2. J. Magn. Reson. Imaging 2017;46:1611–1618.