COTM – October 2026

Discussion

The liver lesion, associated with portal vein thrombosis and hilar lymphadenopathy, raises a differential diagnosis that includes the following entities:

Hepatocellular carcinoma (HCC): HCC is characteristic of steatotic or cirrhotic liver and may occur even in the absence of hepatotropic viral infection, particularly in the context of metabolic syndrome. On CEUS, HCC typically shows rapid arterial wash-in followed by mild wash-out in the portal venous phase, becoming more pronounced in the late phase (>3 minutes). The presence of a portal vein thrombus with the same contrast-enhancement pattern as the liver lesion is highly suggestive of neoplastic invasion (tumour thrombus), rather than benign thrombosis.

Intrahepatic cholangiocarcinoma (ICC): ICC typically shows arterial-phase hyperenhancement, often with a rim-like or heterogeneous pattern, followed by early and marked wash-out (<60 seconds), a key feature distinguishing it from HCC. Unlike HCC, ICC is not typically associated with cirrhosis or steatosis, although it may occur in these settings.

Metastasis: Metastasis is possible in patients with a known primary tumour; however, in this case, the absence of a known primary malignancy and the presence of steatosis make this diagnosis less likely. Portal vein invasion is uncommon in liver metastases, but when present, the tumour thrombus typically shows the same contrast-enhancement pattern as the primary lesion, with arterial enhancement followed by wash-out.

Hepatic adenoma: Hepatic adenoma is rare, occurs most commonly in women of childbearing age, and is usually smaller than 5 cm. Portal vein thrombosis is not a typical complication.

The presence of enlarged hilar lymph nodes is compatible with a malignant liver neoplasm with nodal spread. Among these entities, the combination of a hypervascular lesion with wash-out and a portal vein thrombus with a superimposable contrast-enhancement pattern strongly favours a primary liver malignancy, particularly HCC in the context of metabolic syndrome. However, in a non-cirrhotic patient, the diagnosis cannot be established on imaging alone, and further diagnostic work-up is required.

Additional images

Following CEUS characterisation, the diagnostic work-up was completed with contrast-enhanced abdominal CT and staging chest CT to confirm the imaging findings and assess disease extent.

Image 7. Contrast-enhanced abdominal CT, arterial phase.

A large lesion is seen in the right hepatic lobe, appearing hypodense relative to the surrounding liver parenchyma. A peripheral hypervascular component is evident, corresponding to the area of arterial enhancement observed on CEUS. Within the portal vein, a thrombus is identified, showing peripheral arterial enhancement consistent with the enhancement pattern observed on CEUS.

Image 8. Contrast-enhanced abdominal CT, portal venous phase.

The liver lesion appears hypodense relative to the surrounding liver parenchyma, consistent with wash-out. The portal vein thrombus is confirmed as a filling defect within the vessel lumen, with peripheral enhancement. These findings correspond to those observed on CEUS.

Image 9. Contrast-enhanced abdominal CT, delayed phase.

The liver lesion appears markedly hypodense relative to the surrounding liver parenchyma, consistent with persistent wash-out. The portal vein thrombus is confirmed as a filling defect within the vessel lumen.

Additional discussion

In this case, the patient had no history of cirrhosis, chronic HBV infection, or previous HCC. According to current EASL guidelines, non-invasive diagnostic criteria for HCC cannot be formally applied in this setting, and histological confirmation would usually be required (1).

However, given the highly suggestive CEUS pattern—rapid arterial wash-in followed by late wash-out—and the presence of a portal vein thrombus with a superimposable contrast-enhancement pattern, serum alpha-fetoprotein (AFP) was measured. The AFP level was 24,219 ng/mL, markedly exceeding the 400 ng/mL threshold, which has a specificity of >95% for HCC in patients with an identifiable liver mass (2).

In the presence of markedly elevated AFP and characteristic imaging findings, the multidisciplinary team considered the diagnosis of HCC sufficiently certain. The risk of biopsy-related complications, including neoplastic seeding along the needle tract, estimated at approximately 0.6–1% (3), was weighed against the expected diagnostic benefit. The team therefore decided to proceed directly to staging and treatment planning without histological confirmation.

It is important to emphasise that this decision was made on a case-by-case basis by the multidisciplinary team and was not based on formal non-invasive diagnostic criteria, which do not apply to non-cirrhotic patients. In this specific clinical context, the combination of typical imaging findings, tumour thrombus, and markedly elevated AFP was considered sufficient to establish the diagnosis.
Staging chest CT excluded pulmonary metastases. The patient was referred for Y90-TARE after pre-procedural angioscintigraphy confirmed technical feasibility.

Conclusion

The final diagnosis was hepatocellular carcinoma (HCC) arising in a steatotic liver in a patient with metabolic syndrome, with neoplastic portal vein invasion (tumour thrombus) and metastatic hilar lymphadenopathy.

The diagnosis was based on the characteristic CEUS pattern, the presence of tumour thrombus, and markedly elevated AFP (24,219 ng/mL) in a non-cirrhotic patient. Although current guidelines state that non-invasive criteria do not formally apply in this population, the multidisciplinary team considered the combined imaging and biochemical findings sufficiently diagnostic.

The patient was not considered a candidate for surgical resection or other locoregional therapies, including thermal ablation and TACE, because of portal vein invasion, but was eligible for Y90-TARE (transarterial radioembolization). Pre-Y90 angioscintigraphy confirmed technical feasibility, and the patient was referred for interventional treatment.

Key Learning Points

1. CEUS is a first-line imaging modality for characterising focal liver lesions, particularly when portal vein thrombosis is present.
2. Portal vein invasion showing the same contrast-enhancement pattern as the primary lesion is strongly suggestive of tumour thrombus.
3. In non-cirrhotic patients, non-invasive diagnostic criteria for HCC do not formally apply; however, markedly elevated AFP (>400 ng/mL), together with typical imaging findings, may support a diagnosis without biopsy on a case-by-case basis.
4. Y90-TARE is a valid therapeutic option for patients with advanced HCC and portal vein invasion (BCLC C), provided extrahepatic metastases are absent.

Conflicts of Interest:

The authors declare no conflict of interest.

References

1. European Association for the Study of the Liver. EASL Clinical Practice Guidelines on the management of hepatocellular carcinoma. J Hepatol. 2025;82(2):315-374
2. Chernyak V, Fowler KJ, Kamaya A, et al. Liver Imaging Reporting and Data System (LI-RADS) version 2018: imaging of hepatocellular carcinoma in at-risk patients. Radiology. 2018;289(3):816-830.
3. Van der Pol CB, McInnes MDF, Salameh JP, et al. CT/MRI and CEUS LI-RADS Major Features Association with Hepatocellular Carcinoma: Individual Patient Data Meta-Analysis. Radiology. 2022;302(2):326-335.