Dynamic Contrast-Enhanced Ultrasound (DCE-US) for Easy and Rapid Evaluation of Hepatocellular Carcinoma Compared to Dynamic Contrast-Enhanced Computed Tomography (DCE-CT) – A Pilot Study

Abstract

Purpose: To check the feasibility of the easy quantification of tumor vascularization derived from dynamic contrast-enhanced ultrasound (DCE-US) in comparison to dynamic contrast-enhanced computed tomography (DCE-CT) in patients with hepatocellular carcinoma (HCC).

Materials and Methods: 19 patients with cirrhosis and histologically proven HCC prospectively underwent CEUS (SonoVue) and CT (Imeron400). Following CEUS, the software ImageJ was used for the easy quantification of the echogenicity in HCC lesions and tumor-free liver parenchyma. For DCE-CT we used the software Hepacare and created arterial enhancement fraction color maps of the whole liver and HCC lesions.

Results: Unifocal/multifocal HCCs were detected in 12/7 (US) and 10/9 patients (CT) and biopsied nodules were defined as a reference lesion with a median of 40 mm (US) and 42 mm (CT). CEUS showed HCC-typical hyper-/hypoenhancement in the arterial/late phase in 16/19 reference lesions, while all reference lesions showed an HCC-typical vascular pattern in CT. With DCE-US, quantitative assessment could not be performed in 3/19 patients due to respiratory motion or insufficient image quality. 13/16 reference lesions showed an HCC-typical vascular pattern. Quantitative assessment was possible with DCE-CT in all patients and all reference nodules showed HCC-typical values of the arterial enhancement fraction. There was no statistical difference between CEUS, DCE-US and DCE-CT in the quantitative assessment of contrast enhancement.

Conclusion: The quantitative evaluation of DCE-US was feasible in HCC without a statistical difference with respect to DCE-CT. Further studies with a larger study population including small nodules ≤ 2 cm are needed to assess whether this technique is helpful in routine ultrasound.

Zusammenfassung

Ziel: Vergleich der Durchführbarkeit einer einfachen Quantifizierung der Vaskularisation von hepatozellulärem Karzinom (HCC) mittels dynamisch kontrastmittelverstärktem Ultraschall (DCE-US) versus dynamisch kontrastmittelverstärkter Computertomografie (DCE-CT).

Material und Methoden: 19 Patienten mit Leberzirrhose und histologisch bestätigtem HCC wurden mit CEUS und CT untersucht. Im Anschluss an CEUS wurde mittels der Software ImageJ die Echogenität von HCC-Läsionen sowie Leberparenchym errechnet. Für DCE-CT wurden mittels der Software Hepacare AEF-Farbtafeln für die gesamte Leber und HCC-Herde erstellt.

Ergebnisse: Unifokale/multifokale HCCs zeigten sich bei 12/7 (US) und 10/9 Patienten (CT). Es wurde bei mehreren Läsionen der biopsierte Herd als Referenzläsion mit einem Median von 40 mm (US) und 42 mm (CT) bestimmt. Mittels CEUS zeigten 16/19 Referenzläsionen HCC-typische Hyper-/Hypovaskularisierung in der arteriellen/Spätphase, während alle Referenzläsionen in der CT ein HCC-typisches Vaskularisationsmuster zeigten. Bei 3/19 der Patienten konnte durch Atembewegungen oder unzureichende Bildqualität kein DCE-US erhoben werden; bei 13/16 Patienten konnten HCC-typische Vaskularisationsbefunde erhoben werden. In der DCE-CT zeigten sich bei allen Referenzläsionen HCC-typische AEF-Werte. Es bestand kein statistisch signifikanter Unterschied zwischen den Ergebnissen von CEUS, DCE-US und DCE-CT.

Schlussfolgerung: Mittels DCE-US war die Erhebung quantitativer Daten in der Mehrzahl der Patienten ohne statistischen Unterschied zur DCE-CT möglich. Studien mit größeren Fallzahlen inklusive Läsionen ≤ 2 cm sind erforderlich, um den Nutzen dieser einfach durchführbaren Methode im klinischen Alltag zu überprüfen.

Key words

abdomen - ultrasound computed tomography (US/CT) - technology assessment

• References

• 1 Kim KW, Lee JM, Klotz E et al. Quantitative CT color mapping of the arterial enhancement fraction of the liver to detect hepatocellular carcinoma. Radiology 2009; 250: 425-434
• 2 Platt JF, Francis IR, Ellis JH et al. Liver metastases: early detection based on abnormal contrast material enhancement at dual-phase helical CT. Radiology 1997; 205: 49-53
• 3 Platt JF, Francis IR, Ellis JH et al. Difference in global hepatic enhancement assessed by dynamic CT in normal subjects and patients with hepatic metastases. J Comput Assist Tomogr 1997; 21: 348-354
• 4 Claudon M, Cosgrove D, Albrecht T et al. Guidelines and good clinical practice recommendations for contrast enhanced ultrasound (CEUS) – update 2008. Ultraschall in Med 2008; 29: 28-44
• 5 Dietrich CF, Averkiou MA, Correas JM et al. An EFSUMB Introduction into Dynamic Contrast-Enhanced Ultrasound (DCE-US) for Quantification of Tumour Perfusion. Ultraschall in Med 2012; 33: 344-351
• 6 Strobel D, Seitz K, Blank W et al. Contrast-enhanced ultrasound for the characterization of focal liver lesions – diagnostic accuracy in clinical practice (DEGUM multicenter trial). Ultraschall in Med 2008; 29: 499-505
• 7 Soder RB, Baldisserotto M, Duval da Silva V. Computer-assisted ultrasound analysis of liver echogenicity in obese and normal-weight children. Am J Roentgenol Am J Roentgenol 2009; 192: W201-205
• 8 Ayyappan AP, Jhaveri KS. CT and MRI of hepatocellular carcinoma: an update. Expert Rev Anticancer Ther 2010; 10: 507-519
• 9 Strobel D, Bernatik T, Blank W et al. Diagnostic accuracy of CEUS in the differential diagnosis of small (</= 20 mm) and subcentimetric (</= 10 mm) focal liver lesions in comparison with histology. Results of the DEGUM multicenter trial. Ultraschall in Med 2011; 32: 593-597
• 10 Seitz K, Greis C, Schuler A et al. Frequency of tumor entities among liver tumors of unclear etiology initially detected by sonography in the noncirrhotic or cirrhotic livers of 1349 patients. Results of the DEGUM multicenter study. Ultraschall in Med 2011; 32: 598-603
• 11 SonoVue (sulphur hexafluoride microbubbles) – contrast agent for contrast-enhanced ultrasound imaging of the liver. 2012 http://www.nice.org.uk/nicemedia/live/13888/60721/60721.pdf
• 12 Strobel D, Seitz K, Blank W et al. Tumor-specific vascularization pattern of liver metastasis, hepatocellular carcinoma, hemangioma and focal nodular hyperplasia in the differential diagnosis of 1,349 liver lesions in contrast-enhanced ultrasound (CEUS). Ultraschall in Med 2009; 30: 376-382
• 13 Colombo M. Screening and diagnosis of hepatocellular carcinoma. Liver Int 2009; 29 (Suppl. 01) 143-147
• 14 Takayasu K, Muramatsu Y, Furukawa H et al. Early hepatocellular carcinoma: appearance at CT during arterial portography and CT arteriography with pathologic correlation. Radiology 1995; 194: 101-105
• 15 Gaiani S, Celli N, Piscaglia F et al. Usefulness of contrast-enhanced perfusional sonography in the assessment of hepatocellular carcinoma hypervascular at spiral computed tomography. J Hepatol 2004; 41: 421-426
• 16 Goertz RS, Bernatik T, Strobel D et al. Software-based quantification of contrast-enhanced ultrasound in focal liver lesions – a feasibility study. Eur J Radiol 2010; 75: e22-26
• 17 Quaia E, Palumbo A, Rossi S et al. Comparison of visual and quantitative analysis for characterization of insonated liver tumors after microbubble contrast injection. Am J Roentgenol Am J Roentgenol 2006; 186: 1560-1570
• 18 Wilson SR, Kim TK, Jang HJ et al. Enhancement patterns of focal liver masses: discordance between contrast-enhanced sonography and contrast-enhanced CT and MRI. Am J Roentgenol Am J Roentgenol 2007; 189: W7-W12