Aim: To define the prevalence of different multidetector-row computed tomography (MDCT) vascular patterns and their histopathological correlation with liver explants, and to evaluate the accuracy of MDCT for the diagnosis of hepatocellular carcinoma (HCC).
Methods: We retrospectively reviewed 125 cirrhotic patients imaged by MDCT before liver transplantation. Three main vascular patterns were identified: hypervascular lesion with washout (Hyper-L-Wo), hypervascular lesion without washout (Hyper-L) and non-hypervascular lesion (Hypo-L). Radiological findings were matched with histopathology of explants.
Results: Positive predictive value (PPV) and likelihood ratio (LR) were 95% and 18.66, respectively, for Hyper-L-Wo; 45% and 0.82 for Hyper-L; and 75% and 3 for Hypo-L of 20 mm or larger. Overall accuracy of MDCT for detection and characterisation of HCC was 89% and 43%, respectively. Sensitivity of MDCT for detection and characterisation was related to the lesion size, ranging from 78% (lesion smaller than 10 mm) to 98% (larger than 20 mm) and from 9% to 64%, respectively. MDCT established the accurate stage of disease in 46% of the patients, underestimated in 52% and overestimated in 2%.
Conclusion: In cirrhotic patients, any Hyper-L-Wo detected by MDCT can be confidently considered to be HCC. Hyper-L larger than 10 mm and Hypo-L of 20 mm or larger are at high risk of HCC. However, even using MDCT and the newest imaging protocols, imaging underestimated the diagnosis of small HCC.