Validation of an extension of the international non-invasive criteria for the diagnosis of hepatocellular carcinoma to the characterization of macroscopic portal vein thrombosis.

BACKGROUND AND AIM

We aimed to validate the non-invasive criteria for the characterization of portal vein thrombosis (PVT) in patients with cirrhosis and hepatocellular carcinoma (HCC). In a prospective study, we examined the impact of arterial hypervascularity, as established by the European Association for the Study of the Liver and the American Association for the Study of Liver Diseases recommendations for the non-invasive diagnosis of HCC, as a criterion for characterizing macroscopic PVT (EASL/AASLD extension criteria).

METHODS

A total of 96 cases of PVT detected using ultrasonography in patients with cirrhosis and HCC were included in the study. When coincidental arterial hypervascularity was detected by contrast perfusional ultrasonography and helical computed tomography, the thrombus was considered malignant according to our EASL/AASLD extension criteria. In all cases, an ultrasound-guided biopsy examination of the thrombus was performed.

RESULTS

Coincidental hypervascularity was found in 54 of 96 nodules (56.2%), and all were malignant upon biopsy (100% positive predictive value). Twenty-four (25%) had negative results with both techniques (non-vascular thrombus). Biopsies showed HCC in five non-vascular thrombi (5.3% of all thrombi) and in 13 of 18 thrombi with a hypervascularity result from only one technique.

CONCLUSIONS

The EASL/AASLD extension criteria for non-invasive diagnosis of malignant thrombosis were satisfied in 75.2% of malignant thrombi; thus, a biopsy is frequently required in this setting. However, in the presence of coincidental hypervascularity of a thrombus with both techniques, a biopsy is not required (absolute positive predictive value for malignancy). Relying on imaging techniques in thrombi could miss the diagnosis of malignant portal invasion in up to 24.9% of cases.