Abstract
Objectives
To investigate the diagnostic value of dual-energy computed tomography (DECT) in differentiating between low- and high-risk thymomas and thymic carcinomas.
Materials
Our institutional review board approved this study, and patients provided informed consent. We prospectively enrolled 37 patients (20 males, mean age: 55.6 years) with thymic epithelial tumour. All patients underwent DECT. For quantitative analysis, two reviewers measured the following tumour parameters: CT attenuation value in contrast Hounsfield units (CHU), iodine-related HU and iodine concentration (mg/ml). Pathological results confirmed the final diagnosis.
Results
Of the 37 thymic tumours, 23 (62.2 %) were low-risk thymomas, five (13.5 %) were high-risk thymomas and nine (24.3 %) were thymic carcinomas. According to quantitative analysis, iodine-related HU and iodine concentration were significantly different among low-risk thymomas, high-risk thymomas and thymic carcinomas (median: 29.78 HU vs. 14.55 HU vs. 19.95 HU, p = 0.001 and 1.92 mg/ml vs. 0.99 mg/ml vs. 1.18 mg/ml, p < 0.001, respectively).
Conclusion
DECT using a quantitative analytical method based on iodine concentration measurement can be used to differentiate among thymic epithelial tumours using single-phase scanning.
Key Points
• IHU and IC were lower in high-risk thymomas/carcinomas than in low-risk thymomas
• IHU and IC were lower in advanced-stage thymomas than in early-stage thymomas
• Dual-energy CT helps differentiate among thymic epithelial tumours.
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Abbreviations
- CHU:
-
Contrast Hounsfield unit
- DECT:
-
Dual-energy computed tomography
- HU:
-
Hounsfield unit
- IC:
-
Iodine concentration
- IHU:
-
Iodine-related Hounsfield unit
- VOI:
-
Volume of interest
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Acknowledgments
The scientific guarantor of this publication is Jin Hur, MD, PhD. The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. This study was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012-R1A1A1013152). One of the authors has significant statistical expertise. Dr. Kyunghwa Han (Severance Hospital, Yonsei University College of Medicine) provided statistical advice in this study. Institutional Review Board approval was obtained. Written informed consent was obtained from all patients in this study. Methodology: prospective, diagnostic or prognostic study, performed at one institution.
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Chang, S., Hur, J., Im, D.J. et al. Volume-based quantification using dual-energy computed tomography in the differentiation of thymic epithelial tumours: an initial experience. Eur Radiol 27, 1992–2001 (2017). https://doi.org/10.1007/s00330-016-4542-9
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DOI: https://doi.org/10.1007/s00330-016-4542-9