Radiofrequency Ablation Must Be Assessed by Pathological Methods
Authors: Gisele N'Kontchou, Michel Beaugrand, Olivier Seror
Journal: Hepatology (2009)

We fully agree with Dr. Rodriguez-Sanjùn et al.1 concerning the importance of pathological examination after radiofrequency ablation (RFA), and we recognize the importance of their work that confirms previous reports.2 Nevertheless, we cannot endorse their comment about our article3 which suggest that RFA is only a palliative method in terms of completeness of tumor ablation. RFA is a name that covers disparate methods of treatment. From this point of view, there are some similarities with surgery. The authors would easily recognize that surgical results are not similar after enucleation versus anatomic resection or according to the experience of the operator. The field of RFA is filled with even more heterogeneity and the need for technical excellence is comparable. Differences from case to case might involve not only the experience of the operator, the type of probe, the type of cooling system but also the method itself.4 The multiprobe multipolar technique that we have used since 2005 provides a larger and more focused and predictable volume of ablation, which allows treating larger tumors with a safety margin up to 1 cm.5 This point is essential for achieving a complete histologically proven response. Conversely to patients treated by RFA using a single electrode, the patients treated by multipolar multiprobe technique who have been secondarily transplanted in our series did not have any tumoral remnants detectable by a careful histological examination either inside the tumor or in its immediate vicinity (unpublished data). The goal of RFA must be similar to surgery in terms of managing a safety margin, and this goal is reachable by new RFA techniques. Local recurrences nevertheless are not the main concern in these patients. We observed local recurrences in patients who have been treated by monopolar techniques. These local recurrences were usually accessible to a new RFA procedure with a curative purpose, and this type of recurrence did not influence the overall survival, at least in a statistically significant way. This emphasizes the fact that small tumors (which are increasingly recognized by screening) are accessible to a local curative treatment irrespective of the treatment type, but unfortunately this does not mean the patients are cured and will survive. Survival and the quality of survival are the main goals of any treatment in medicine. In the particular case of small hepatocellular carcinomas developed in a cirrhotic liver, the main causes of death are distant recurrences and liver failure. The meaning of distant recurrences is debated, but most of these recurrences which deal with initially small tumors seem to result from the emergence of new tumors, as suggested by their annual incidence (around 10%-15%/year) almost steady over time during the first 5 years and comparable with that observed after liver resection. 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 the patient, (2) it is less costly, (3) it is less damaging to nontumorous liver parenchyma, (4) it allows treatment of recurrences in most cases, with the same curative purpose, and (5) most of all, it has very limited contraindications and widely increases the number of patients eligible for a locally curative therapy. Facts seem in accordance with these theoretical views. Patients do prefer RFA to surgery and the overall survival of patients eligible for surgery but submitted to RFA is at least as good as their surgical counterparts, even in the case where a monopolar electrode has been used, which is almost universal in the literature and which concerned around two-thirds of our patients. We are confidently waiting for even better results with the multiprobe multipolar technique, both in terms of complete (and histologically proven) ablation and in terms of survival. Gisele N'Kontchou*, Michel Beaugrand*, Olivier Seror , * Department of Hepatogastroenterology, Bondy, France, Department of Radiology, Hôpital Jean Verdier, (Assistance Publique-Hôpitaux de Paris), Bondy, France.