Abstract
Objective The purpose of this study was to find out the incidence of typical and atypical radiological
imaging findings of hepatocellular carcinoma (HCC) on multiphase multidetector computed
tomography (MDCT) scans in histologically proven cases.
Materials and Methods A multiphase computed tomography study of 73 patients with histologically proven
HCC was evaluated by a radiologist. Our multiphasic protocol was composed of precontrast,
arterial, portal, and delayed venous phases. The reviewers analyzed the CT images
for tumor size, enhancement patterns of HCC in different phases, relative timing of
washout, internal cystic changes, and presence of dysmorphic intratumoral vessel aneurysms
or arteriovenous shunt.
Results Most of the cases (95.9%) showed typical enhancement patterns in MDCT, i.e., enhancements
in the arterial phase with the portal or delayed venous phase contrast washout. Three
cases (4.9%) out of 73 HCC showed enhancements in the portal phase and washout in
the delayed venous phase. Seven cases out of total 73 HCC (9.5%) patients showed heterogeneous
enhancements in both arterial and portal phases and contrast washout in the delayed
venous phase. Venous thrombosis was noted in about 44 cases (60%) out of total 73
patients, in which portal vein thrombosis was more common than hepatic veins/inferior
vena cava.
Conclusion Most of the HCC show typical enhancement patterns, i.e., heterogeneous enhancements
in the arterial phase and washout in the portal venous phase when we use MDCT. These
findings are higher than those described previously. However, in our study, the main
difference with MDCT was lower frequency of intratumoral pseudoaneurysm and bile duct
invasion, and intratumoral fat and calcification (atypical character of HCC) were
not found which were rare findings in previous study.
Keywords
HCC - Cystic changes - Multiphasic MDCT scan - Intratumoral pseudoaneurysm
