MR imaging of hepatocellular carcinoma: Relationship between lesion size and imaging findings, including signal intensity and dynamic enhancement patterns

✍ Scribed by Indra C. van den Bos; Shahid M. Hussain; Roy S. Dwarkasing; Wim C.J. Hop; Pieter E. Zondervan; Robert A. de Man; Jan N.M. IJzermans; Craig W. Walker; Gabriel P. Krestin

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 873 KB
• Volume: 26
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.21046

✦ Synopsis

Abstract

Purpose

To assess the relationship between lesion size and MR imaging findings of pathologically‐proven hepatocellular carcinoma (HCC).

Materials and Methods

In a retrospective, single‐center study, 37 consecutive patients were identified between 1999 and 2005 that underwent preoperative MRI and surgical resection of HCC. A total of 47 lesions (mean size = 6.85 cm, range = 1–25 cm) were assessed for signal intensity (SI), enhancement patterns, and secondary morphologic features. Interobserver rating, percentage enhancement, and contrast‐to‐noise‐ratio (CNR) were determined. Lesions were assessed for combinations of typical MRI features. Regression analysis was used to assess relations between MRI findings and tumor size.

Results

On fat‐suppressed T2‐weighted (T2w) fast‐spin‐echo, smaller lesions had lower SI compared to larger lesions (P < 0.05). In the arterial phase, smaller lesions showed significantly higher percentage enhancement compared to larger lesions (P < 0.05). In the delayed phase, smaller lesions showed less pronounced washout (P < 0.05). Heterogeneity of the lesions, including fatty infiltration, internal nodules, or mosaic pattern, was observed significantly more frequently in larger lesions (P < 0.001). The classic combination of high T2w signal, strong arterial enhancement, and delayed phase washout was present in 23 of 44 lesions (52%).

Conclusion

Smaller HCC often showed lower SI on T2w, more intense arterial enhancement, and less pronounced delayed washout compared to larger HCC. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.