Korean J Radiol.  2008 Aug;9(4):325-332. 10.3348/kjr.2008.9.4.325.

Early Hepatocellular Carcinoma: Three-Phase Helical CT Features of 16 Patients

• Lee J
• Lee WJ
• Lim HK
• Lim JH
• Choi N
• Park MH
• Kim SW
• Park CK

• KMID: 1076458
• DOI: http://doi.org/10.3348/kjr.2008.9.4.325

Abstract

OBJECTIVE
To evaluate the three-phase helical CT features of early hepatocellular carcinomas, based on the new Japanese classification. MATERIALS AND METHODS: Over the course of an eight-year period, we collected 16 pathologically proven early hepatocellular carcinomas from 16 patients having undergone a three-phase helical CT prior to surgery. The three-phase CT images were acquired at 20-35 sec (arterial phase), 70 sec (portal phase), and 180 sec (equilibrium phase) from the begining of intravenous injection of contrast material. All the CT images were retrospectively analyzed by two radiologists in consensus, based on their description of morphologic (size, margin, fibrous capsule and mosaic pattern) and enhancement patterns of tumors. RESULTS: Only seven (44%) of the 16 early hepatocellular carcinomas having undergone a CT were described (mean diameter, 1.2 cm; range, 0.4-2.5 cm). All the tumors had an ill-defined margin with no fibrous capsule. The mosaic pattern was found in only one tumor. Only three (43%) of the seven tumors detected on CT were hyperattenuating during the arterial phase. The four remaining tumors (25%) were hypoattenuating throughout the three phases. CONCLUSION: Despite the higher resolution provided by the three phase scans, the contrast-enhanced CT provides only limited detection of the variable morphologic and enhancement features of early hepatocellular carcinomas.

Keyword

Hepatocellular carcinoma; Liver neoplasms; Computed tomography (CT)

MeSH Terms

Adult
Carcinoma, Hepatocellular/pathology/*radiography
Female
Humans
Liver Neoplasms/pathology/*radiography
Male
Middle Aged
Retrospective Studies
*Tomography, Spiral Computed

Figure

• 

  Fig. 1 62-year-old man with early hepatocellular carcinoma located in right hepatic lobe. A. Photograph of resected gross specimen shows 2.2-cm, slightly yellowish nodule (arrows) with indistinct margin. B. Photomicrograph of same specimen shows tumor cells of well-differentiated hepatocellular carcinoma in lower half of field (below arrows). Note that tumor cells appear to replace normal hepatocytes without clear demarcation (i.e. replacement growth - Hematoxylin & Eosin staining, ×100).

• 

  Fig. 2 48-year-old man with early hepatocellular carcinoma of so called "nodule in nodule lesion" (i.e. early advanced hepatocellular carcinoma) located in right hepatic lobe. A. Axial helical CT scan of liver during arterial phase shows 1.8-cm, hypoattenuating nodule with indistinct margin (arrows) located in segment VI of right hepatic lobe. Note faintly enhancing portion (arrowheads) within hypoattenuating nodule, representing mosaic pattern (nodule-in-nodule pattern). B, C. Corresponding portal (B) and equilibrium (C) phase CT scans show same hypoattenuating nodule (arrows). Faintly enhancing portion observed in arterial phase image becomes isoattenuating during later phases. D. Photograph of Hematoxylin and Eosin stained resected specimen shows same nodule (arrows) with indistinct margin and uneven fatty change. Note small nodule (arrowheads) in its upper part (i.e. mosaic pattern - nodule-in-nodule pattern), which corresponds to faintly enhancing portion observed in arterial phase CT image. Histopathologic findings revealed that whole nodule was composed of tumor cells of well-differentiated hepatocellular carcinoma, while small nodule was composed of moderately differentiated hepatocellular carcinoma.

• 

  Fig. 3 54-year-old man with early hepatocellular carcinoma located in right hepatic lobe. A. Three-phase helical CT image obtained during arterial phase shows 0.8cm, faintly hyperattenuating nodule with indistinct margin (arrows) in segment VI of right hepatic lobe. B, C. Corresponding portal (B) and equilibrium (C) phase CT scans show that hyperattenuating nodule observed in arterial phase becomes isoattenuating during portal and equilibrium phases (arrows).

• 

  Fig. 4 51-year-old woman with early hepatocellular carcinoma located in right hepatic lobe. A. Three-phase helical CT image obtained during arterial phase shows 1.3-cm, hypoattenuating nodule with indistinct margin (arrows) in segment V of right hepatic lobe. B, C. Corresponding portal (B) and equilibrium (C) phase CT scans show same hypoattenuating nodule (arrows) in segment V of right hepatic lobe.

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