Iodine quantification to distinguish hepatic neuroendocrine tumor metastasis from hepatocellular carcinoma at dual-source dual-energy liver CT

• Published in: European journal of radiology Vol. 105; pp. 20 - 24
• Main Authors: Kaltenbach, Benjamin, Wichmann, Julian L., Pfeifer, Sophia, Albrecht, Moritz H., Booz, Christian, Lenga, Lukas, Hammerstingl, Renate, D’Angelo, Tommaso, Vogl, Thomas J., Martin, Simon S.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.08.2018
• Subjects: Dual-energy CT; Hepatocellular carcinoma; Iodine quantification; Liver imaging; Neuroendocrine tumors; Dual-energy CT; Hepatocellular carcinoma; Iodine quantification; Liver imaging; Neuroendocrine tumors
• ISSN: 0720-048X; 1872-7727
• DOI: 10.1016/j.ejrad.2018.05.019

•Contrast-enhanced DECT with iodine quantification improves the differentiation of hepatic NET metastasis and HCC.•Iodine uptake and NIU yielded a significantly better diagnostic performance compared to standard evaluation.•NIU showed the strongest diagnostic performance with 100% sensitivity and 90.2% specificity.•Unenhanced attenuation and fat fraction values showed no significant differences between hepatic NET metastases and HCC. To investigate the value of third-generation dual-source dual-energy computed tomography (DECT) iodine quantification to distinguish hepatic neuroendocrine tumor (NET) metastasis from hepatocellular carcinoma (HCC) in non-cirrhotic liver parenchyma. Forty-six patients (mean age, 64.9 ± 10.1 years; 28 male and 18 female) with either hepatic NET metastasis or HCC, who had undergone liver DECT, were included in this retrospective study. For each lesion, arterial-phase attenuation values and DECT quantitative parameters, including iodine uptake, fat fraction, normalized iodine uptake (NIU), and lesion-to-liver-parenchyma ratio (LPR) were evaluated. Available cumulative data from histopathology, MRI, PET/CT, or interval imaging follow-up served as the reference standard for all liver lesions. In addition, the diagnostic accuracy of contrast-enhanced and material decomposition analysis for the differentiation of hepatic NET metastasis and HCC was assessed using receiver operating characteristics (ROC) curve analysis. Hepatic NET metastasis and HCC showed significant differences in arterial attenuation (P = 0.003), iodine uptake (P < 0.001), NIU (P < 0.001), and LPR (P = 0.003). No significant differences were found for unenhanced attenuation and fat fraction values (P = 0.686 and P = 0.892, respectively). NIU showed superior sensitivity (100%; iodine uptake, 71%), while both iodine uptake and NIU revealed superior specificity (100% and 90%, respectively) compared to LPR (sensitivity, 96%; specificity, 80%) and arterial attenuation analysis (sensitivity, 79%; specificity, 80%) (P ≤ 0.016). Third-generation DECT with assessment of iodine uptake improves the differentiation of hepatic NET metastasis and HCC in non-cirrhotic liver, with NIU showing the strongest diagnostic performance.