Percutaneous electrochemotherapy in the treatment of portal vein tumor thrombosis at hepatic hilum in patients with hepatocellular carcinoma in cirrhosis: A feasibility study

AIM To treated with electrochemotherapy(ECT) a prospective case series of patients with liver cirrhosis and Vp3-Vp4- portal vein tumor thrombus(PVTT) from hepatocellular carcinoma(HCC), in order to evaluate the feasibility, safety and efficacy of this new non thermal ablative technique in those patients. METHODS Six patients(5 males and 1 female), aged 61-85 years(mean age, 70 years), four in Child-Pugh A and two in Child-Pugh B class, entered our study series. All patients were studied with three-phase computed tomography(CT), contrast enhanced ultrasound(CEUS) and ultrasound-guided percutaneous biopsy of the thrombus before ECT. All patients underwent ECT treatment(Cliniporator Vitae?, IGEA Sp A, Carpi, Modena, Italy) of Vp3-Vp4 PVTT in a single session. At the end of the procedure a post-treatment biopsy of the thrombus was performed. Scheduled follow-up in all patients entailed: CEUS within 24 h after treatment; triphasic contrastenhanced CT and CEUS at 3 mo after treatment and every six months thereafter.RESULTS Post-treatment CEUS showed complete absence of enhancement of the treated thrombus in all cases. Post-treatment biopsy showed apoptosis and necrosis of tumor cells in all cases. The follow-up ranged from 9 to 20 mo(median, 14 mo). In 2 patients, the followup CT and CEUS demonstrated complete patency of the treated portal vein. Other 3 patients showed a persistent avascular non-tumoral shrinked thrombus at CEUS and CT during follow-up. No local recurrence was observed at follow-up CT and CEUS in 5/6 patients. One patient was lost to follow-up because of death from gastrointestinal hemorrage 5 wk after ECT. CONCLUSION In patients with cirrhosis, ECT seems effective and safe for curative treatment of Vp3-Vp4 PVTT from HCC.

Contrast-enhanced ultrasound in differentiating malignant from benign portal vein thrombosis in hepatocellular carcinoma

Portal vein thrombosis(PVT) may occur in liver cirrhosis patients. Malignant PVT is a common complication in cirrhotic patients with concomitant hepatocellular carcinoma(HCC) and, in some cases, it may be even the initial sign of an undetected HCC. Detection of malignant PVT in a patient with liver cirrhosis heavily affects the therapeutic strategy. Gray-scale ultrasound(US) is widely unreliable for differentiating benign and malignant thrombi. Although effective for this differential diagnosis, fine-needle biopsy remains an invasive technique. Sensitivity of color-doppler US in detection of malignant thrombi is highly dependent on the size of the thrombus. Contrast-enhanced computed tomography(CT) and contrast-enhanced magnetic resonance(MRI) can be useful to assess the nature of portal thrombus, while limited data are currently available about the role of positron emission tomography(PET) and PET-CT. In contrast with CT, MRI, PET, and PET-CT, contrast-enhanced ultrasound(CEUS) is a fast, effective, well tolerated and cheap technique, that can be performed even in the same session in which the thrombus has been detected. CEUS can be performed bedside and can be available also in transplanted patients. Moreover, CT and MRI only yield a snapshot analysis during contrast diffusion, while CEUS allows for a continuous real-time imaging of the microcirculation that lasts several minutes, so that the whole arterial phase and the late parenchymal phase of the contrast diffusion can be analyzed continuously by real-time US scanning. Continuous real-time monitoring of contrast diffusion entails an easy detection of thrombus maximum enhancement. Moreover, continuous quantitative analyses of enhancement(wash in- wash out studies) by CEUS during contrast diffusion is nowadays available in most CEUS machines, thus giving a more sophisticated and accurate evaluation of the contrast distribution and an increased confidence in diagnosis in difficult cases. In conclusion, CEUS is avery reliable technique with a high intrinsic sensitivity for portal vein patency assessment. More expensive and sophisticated techniques(i.e., CT, MRI, PET, and PET-CT) should only be indicated in undetermined cases at CEUS.