CT상 단일 종괴로 나타난 간전이의 간농양과의 감별에 있어서의 함정

Abstract

OBJECTIVE: During the follow-up period of extrahepatic malignancy, one may encounter a solitary hepaticmetastasis on CT scan which may be difficult to differentiate from hepatic abscess in an ambiguous clinicalsetting.It was our intention to copmare the radiological similarities and differences between two disease entitiesfrom which differentiation can be attempted. MATERIALS AND METHOD: Thirty-six cases of solitary heaptic meastesisand 23 cases of liver abscess were included in this study. Two radiologists interpreted the CT wihout knowledge ofthe clinical information. CT pattern was categorized and the frequency of various findings were compared betweenthe two groups. CT findings of the mass were analysed in misinterpreted cases. RESULTS: Without the clinicalinformations, the diagnostic accuracy of the mass ws 72-76% without pattern analysis. Homogeneous masses were seenin both groups, but all masses larger than 4cm were metastases. In heterogeneous masses, metatases more frequentlyaccompained high attenuation in central or peripheral portion of the mass and showed thick intermediate zone,Irregular trabecular pattern or septations were more frequently observed in abscesses. Biliary dilatation orstone, pleural effusion, air in mass or biliary tree were more frequently seen in abscesses. The false diagnosiswas encountered most frequently when the mass possessed any of the followinngs ; homogeneous attenuation, mosaicpattern in the mass with inhomogeneous attenuation and thin intermediate attenuation area. CONCLUSION: Patternanalysis of the various CT character will be helpful to differentiate hepatic abscess and solitary hepaticmetastasis in the equivocal clinical settings. However, similar pattern can be seen in both entities; in thiscases, corrdination of CT pattern and secondary findings is needed for better differentiation.