Percutaneous ablation procedures in cirrhotic patients with hepatocellular carcinoma submitted to liver transplantation: Assessment of efficacy at explant analysis and of safety for tumor recurrence

Abstract

O rthotopic liver transplantation (OLT) is the ideal treatment for hepatocellular carcinoma (HCC) emerging in liver cirrhosis since both the tumor and the underlying cirrhosis can be cured. 1 According to Mazzaferro et al., 2 OLT should be restricted to patients with single HCC lower than 5 cm or with no more than 3 nodules, each smaller than 3 cm, in order to achieve an acceptable rate of tumor recurrence. Several studies confirmed a 5-year survival of 57 to 74% if these selection criteria are taken into account. 3 -8 However, progressive tumor enlargement, occurrence of new nodules or of vascular invasion may take place precluding transplantation in HCC patients awaiting for OLT. Adjuvant treatments such as transarterial chemoembolization (TACE), percutaneous ethanol injection (PEI), and radiofrequency ablation (RFA) have been used to prevent tumor progression in HCC patients listed for OLT, but a clear confirmation of their usefulness is still lacking. 1 The efficacy evaluation of percutaneous ablation techniques is usually made using imaging techniques such as multiphasic computed tomography (CT) and magnetic resonance imaging, assessing the presence of residual arterial vascularization within the nodule. Based upon imaging techniques, the rate of short-term complete necrosis of small HCCs lower than 3 cm has been shown to be 70 to 80% after PEI 9,10 and 90 to 93% after RFA. 10,11 The model of the explanted liver provides an unique opportunity to validate the ablation techniques allowing to evaluate their efficacy result from a pathological point of view. However, there are

Actual therapeutic efficacy of pre-transplant treatment on hepatocellular carcinoma and its impact on survival after salvage living donor liver transplantation

“…Previously, Kim et al 19 reported that a viable tumor volume ratio greater than 10% after preLT therapy was a significant prognostic factor. Pompili et al 20 also reported that 58.7% of HCC had partial necrosis after percutaneous ablation procedures and the effect depended on the size of HCCs. Also, Wong et al reported that fifteen nodules in five patients had <75% necrosis and these were due to local/non-local recurrences or perhaps suboptimal treatment with RFA, TACE or cisplatin gel injection.…”

Bridge Treatments for HCC in the Waiting List for Liver Transplantation

“…These studies show that complete tumor necrosis (evaluated on the explanted liver) may be achieved in 47-75% of the cases with a mean value of 58% [25][26][27][28][29]. A clear different effectiveness can be demonstrated analysing tumors of different size.…”

“…A clear different effectiveness can be demonstrated analysing tumors of different size. In fact, the rate of complete necrosis ranges between 50% and 78% in tumors up to 3 cm and between 13% and 43% in larger tumors [25][26][27]29]. Furthermore, a tumor size exceeding 3 cm resulted the only risk factor for HCC persistence after treatment in two studies [25,27].…”

“…Indeed, the mean rate of major complications was as high as 7%, including one case of death due to peritoneal bleeding, two cases of acute peritonitis/cholecystitis, and one case each of severe liver failure treated by urgent transplantation, severe persistent liver failure, biliary stenosis, arterial hemorrage and small bowel perforation [25][26][27][28]. Additionally, the risk of tumor seeding along the needle track through the abdominal wall appears to be low since only one case has been reported in literature [30]; HCC recurrence after LT has been shown to be rare (3% on average) ( Table 3).…”

Radiofrequency Ablation Must Be Assessed by Pathological Methods

“…This view is also in accordance with the fact that molecular analysis of the nontumorous liver parenchyma is predictive of such recurrences conversely to molecular analysis of the removed tumor. 6 In such a setting, it is clear that only transplantation could be called "curative", but in the numerous patients who are not eligible for such a procedure, the advantages of RFA over surgery are impressive: (1) RFA has lesser morbidity and mortality and is more comfortable for HEPATOLOGY, Vol. 51, No.…”