Clinical features and natural history of portal vein thrombosis after radiofrequency ablation for hepatocellular carcinoma in Japan.

PURPOSE: Little is known about portal vein thrombosis (PVT) after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). We aimed to determine the incidence, background, and natural history of RFA-related PVT.

METHODS

This is a retrospective study of 317 patients (219 males and 98 females) with HCC treated by RFA. Clinical data were compared between patients with and without PVT detected by ultrasound/CT. The median follow-up period after RFA was 15.8 months.

RESULTS

PVT was detected in 6 (1.9 %) of 317 patients, 6 (0.8 %) of 802 treatments for HCC, and 6 (0.6 %) of 964 sessions of RFA. Body mass index was significantly higher in patients with PVT (26.9 ± 3.1 kg/m(2)) than in those without (22.9 ± 3.5 kg/m(2), p = 0.0075). PVT was significantly more frequent in RFA for the left lobe of the liver (2.7 %) than for the other sites (0 %, p < 0.0001). Five of the six patients received no treatment for PVT, with natural outcomes of disappearance in one patient, improvement in one patient, and unchanged appearance in three patients. Anticoagulation was applied in the one remaining patient and resulted in a successful recanalization. In the six patients, there was no significant difference in hepatic functional reserve between baseline and time of detection of PVT.

CONCLUSIONS

These results indicated that a high body mass index and RFA for HCC in the left lobe might be significant risk factors for PVT and that RFA-related PVT was rarely progressive with little influence on liver function.