Small hepatocellular carcinoma keeping hypodense during dual phase helical CT scan and correlative pathology

Rationale and Objectives: To evaluate the dual-phase helical computed tomography (CT) appearance of small hepato- cellular carcinoma (SHCC) with hypodense and to evaluate its correlation with pathology. Materials and Methods: The helical CT dual-phase appearance of 33 lesions with keeping hypodense was retrospectively analyzed, all lesions were confirmed as SHCC by histopathology. CT appearance included border, inner density. Results: In 33 lesions, which were confirmed as SHCC by pathology, keeping hypodense during hepatic arterial phase and portal venous phase, 19 lesions are ill-defined borders and 14 lesions are well-defined borders, 22 lesions show homogenous hypodense and 11 lesions show heterogeneous hypodense in non-enhancing CT scan; however, only 9 lesions are ill-defined borders and the other 24 lesions are well-defined borders with slightly irregular contours, only 9 lesions show homogenous hypodense and the other 24 lesions show heterogenous hypodense with flecks of more hypodense in enhancing CT scan. Conclusion: SHCC with hypodense prefers to have a well-defined border with slightly irregular contour, and flecks of more hypodense in the lesion in dual-phase enhancing helical CT scan.