Angiographic Manifestations of Hepatocarcinoma After Radiofrequency Ablation Treatment

Objective To study the hepatic DSA manifestations of hepatocarcinoma after radiofrequency ablation (RFA) treatment, and to provide reference for evaluating RFA effect and selecting proper follow up imaging technique. Materials and Methods Eight male patients with primary liver cancer (n=7) or hepatic metastasis (n=1) were enrolled in this study. Solitary lesion was seen in 6 and double lesions in 2 cases. Tumor's diameter varied within 3～7.5 cm with a mean of 4.3 cm. Common hepatic arteriography or super selective angiography of suspicious tumor area were performed in all patients.Results On DSA, most ablated regions presented as round or ovoid low density areas with no stain. At the lesion's peripheral zone the following five signs could be found: (1) stain of localized granulation tissue; (2) arterio portal fistula; (3) hemorrhage; (4) recurrence; (5) no abnormal findings. Local or intrahepatic recurrence occurred in 7 cases.Conclusion Hepatic DSA has great value in detecting local recurrence of hepatic tumor after RFA treatment. (1) Granulation staining at the peripheral zone of treated region is a common finding, usually appeared in one month after RFA. (2) Arteriovenous shunt, as a complication of RFA, can cover local recurrence because of hepatic hypo perfusion and abnormal portal perfusion. (3) Marginal bleeding presents as patch stain in early arterial phase which lasts into portal phase, while marginal recurrence shows signs of nodular shadow which protrudes beyond the outline of the treated area. (4) No abnormal vascularity should be seen at tumor's border three months after RFA, otherwise, recurrence should be considered. DSA is superior to CT in detecting marginal or intrahepatic recurrent nodule below 1cm.