Abdullah Emre YILDIRIM, Feyza GELEBEK YILMAZ

Relative Contribution of Apparent Diffusion Coefficient (ADC) Values and ADC Ratios of Focal Hepatic Lesions in the Characterization of Benign and Malignant Lesions

Objective: The aim of the present study was to compare relative contribution of apparent diffusion coefficient (ADC) values andADC ratios (ADC of the lesion/ADC of the neighboring hepatic parenchyma) in the differential diagnosis of benign and malignantfocal hepatic lesions.Methods: A total of 80 patients with 94 focal hepatic mass lesions (mean size, 5.3 cm; range, 1–12 cm) were evaluated retrospectivelyusing 3 Tesla magnetic resonance imaging (MRI). The ADC values and ADC ratios were compared for different types of lesionsto obtain ideal cut-off values.Results: Mean ADC values (±SD) were 0.93±0.15, 0.95±0.48, 1.44±0.39, 1.88±0.50, and 2.94±0.75×10−3 mm2/sec respectively forhepatocellular carcinoma (HCC), metastasis, focal nodular hyperplasia (FNH), hemangioma, and cysts with a mean ADC value of1.97±0.68 for benign lesions and 0.94±0.29×10−3 mm2/sec for malignant lesions. The ADC ratios of benign and malignant lesionswere 1.50±0.53 and 0.80±0.20×10−3 mm2/sec, respectively, and the ADC values and ratios were found to differ significantly betweenbenign and malignant lesions. Assuming a cut-off ADC value of 1.26×10−3 mm2/sec for discrimination of benign and malignantlesions provided 94% sensitivity and 92% specificity. Sensitivity of 85% and specificity of 92% were found when a cut-off ADC ratio of 0.90×10−3 mm2/sec was used for discrimination of benign and malignant lesions. Compared to ADC values, ADC ratios werefound to have lower sensitivity and higher specificity for discriminating between benign and malignant lesions.Conclusion: Diffusion weighted imaging is used in combination with conventional MRI, and it enhances the diagnostic accuracy of MRI in the characterization of benign and malignant lesions.

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Koh D, Collins D. Diffusion Weighted MRI in the Body: Applications and Challenges in Oncology. Am J Roentgenol 2007; 188: 1622-35.
Reimer P, Saini S, Hahn PF, Brady TJ, Cohen MS. Clinical application of abominal echoplanar imaging (EPI):optimization using a retrofitted EPI system. J Comput Asist Tomogr 1994; 18: 673-9.
Stejskal EO, Taner JE. Spin diffusion measurements: spin-echo in the presence of a time dependent field gradient. J Chem Phys 1965; 42: 288-92.
Galea N, Cantisani V, Taouli B. Liver lesion detection and characterization: role of diffusion-weighted imaging. J Magn Reson Imaging 2013; 37: 1260-76.
Taouli B, Koh DM. Diffusion-weighted MR imaging of the liver. Radiology 2010; 254: 47-66.
Taouli B, Vilgrain V, Dumont E, Daire JL, Fan B, Menu Y. Evaluation of liver diffusion isotropy and characterization of focal hepatic lesions with two single-shot echo-planar MR imaging sequences: prospective study in 66 patients. Radiology 2003; 226: 71-8.
Koh DM, Padhani AR. Diffusion-weighted MRI: a new functional clinical technique for tumour imaging. Br J Radiol 2006; 79: 633-5.
Papanikolaou N, Gourtsoyianni S, Yarmenitis S, Maris T, Gourtsoyiannis N. Comparison between two-point and four-point methods for quantification of apparent diffusion coefficient of normal liver parenchyma and focal lesions. Value of normalization with spleen. Eur J Radiol 2010; 73: 305-9.
Goshima S, Kanematsu M, Kondo H, Yokoyama R, Kajita K, Tsuge Y, et al. Diffusion-weighted imaging of the liver: optimizing b value for the detection and characterization of benign and malignant hepatic lesions. J Magn Reson Imaging 2008; 28: 691-7.
Chen ZG, Xu L, Zhang SW, Huang Y, Pan RH. Lesion discrimination with breath-hold hepatic diffusion-weighted imaging: a meta-analysis. World J Gastroenterol 2015; 21: 1621-7.
Zech CJ, Grazioli L, Breuer J, Reiser M, Schoenberg SO. Diagnostic performance and description of morphological features of focal nodular hyperplasia in Gd-EOB-DTPA-enhanced liver magnetic resonance imaging: results of a multicenter trial. Investig Radiol 2008; 43: 504-11.
Sandrasegaran K, Akisik FM, Lin C, Tahir B, Rajan J, Aisen AM. The value of diffusion-weighted imaging in characterizing focal liver masses. Acad Radiol 2009; 16: 1208-14.
Hennedige TP, Hallinan JT, Leung FP, Teo LL, Iyer S, Wang G, et al. Comparison of magnetic resonance elastography and diffusion-weighted imaging for differentiating benign and malignant liver lesions. Eur Radiol 2016; 26: 398-406.
Wei C, Tan J, Xu L, Juan L, Zhang SW, Wang L, et al. Differential diagnosis between hepatic metastases and benign focal lesions using DWI with parallel acquisition technique: a meta-analysis. Tumour Biol 2015; 36: 983-90.
Bruix J, Sherman M. American Association for the Study of Liver Diseases. Management of hepatocellular carcinoma: an update. Hepatology 2011; 53: 1020-2.
Kanematsu M, Goshima S, Watanabe H, Kondo H, Kawada H, Noda Y, et al. Detection and characterization of focal hepatic lesions with diffusion-weighted MR imaging: a pictorial review. Abdom Imaging 2013; 38: 297-308.
Schmid-Tannwald C, Thomas S, Ivancevic MK, Dahi F, Rist C, Sethi I, et al. Diffusion-weighted MRI of metastatic liver lesions: is there a difference between hypervascular and hypovascular metastases? Acta Radiol 2014; 55: 515-23.
Lebovici A, Sfrangeu SA, Feier D, Caraiani C, Lucan C, Suciu M, et al. Evaluation of the normal- to-diseased apparent diffusion coefficient ratio as an indicator of prostate cancer aggressiveness. BMC Med Imaging 2014; 14: 15.
Caraiani C, Chiorean L, Fenesan DI, Lebovici A, Feier D, Gersak M. Diffusion Weighted Magnetic Resonance Imaging for the Classification of Focal Liver Lesions as Benign or Malignant. J Gastrointestin Liver Dis 2015; 24: 309-17.