Hepatocellular Carcinoma with Internal Extensive Coagulation Necrosis: Carefulness of Preoperative Imaging Diagnosis and Comparison with Surgical Specimen

Shin, Myong Ho; Chang, Jay Chun; Rho, Byeung Hak; Cho, Jae Ho; Hwang, Mi Soo; Park, Bok Hwan

Abstract

PURPOSE: The aim of this study is to correlate the non-characteristic dual-phase CT imaging findings of hepato-cellular carcinoma with the observed characteristics of surgical specimens.
MATERIALS AND METHODS
We studied four cases in which homogeneous low attenuation was observed during the arterial and delayed phases of dynamic CT scanning and in which hepatocellular carcinoma with coagulation necrosis above 95% was pathologically confirmed. We compared the findings of dual phase CT scanning, ultrasonography, angiography and Lipiodol CT scanning with the observed features of surgical specimens.
RESULTS
Nodules were 30-50 (mean, 41) mm in size, and were round in three cases and oval in one. In all four cases, a low density lesion was observed during the arterial and delayed phases of dual-phase CT scanning. Ultrasonography demonstrated internal echo and the presence of a hypoechoic halo, implying that in all cases a capsule was present. At angiography and LiCT, minimal peripheral and central tumor staining or lipiodol up-take was observed. In all surgical specimens a complete capsule was visible, and histologic structures were mainly of the trabecular type, Edmondson grade II or III was recorded, and the mass had undergone extensive coagulation necrosis (above 95%).
CONCLUSION
In cirrhotic liver which is hepatitis B-antigen positive, clear sonographic findings of internal echo and a capsule, rather than a simple cyst, indicate the possibility of hepatocellular carcinoma with extensive coagulation necrosis. This is so even if the arterial and delayed phases of dual-phase CT scanning indicate the presence of a low-density lesion, and in such cases additional work-up is therefore required.