Reply: Assessment of Hepatocarcinoma Response to Radiofrequency

Abstract

We are grateful for the comments by Pompili et al. [1] concerning our work on hepatocellular carcinoma radiofrequency [2]. We found a low complete pathologic response rate of 46.7% and no significant difference between tumors with a diameter smaller or greater than 3 cm. Pompili et al. are disappointed by this fact since in their own experience [2] and that of others [3], nodes smaller than 3 cm have a higher pathologic response rate. It is logical to expect such correlation since the area of high temperature produced by the radiofrequency device can better pass over the boundaries of smaller tumors than those of larger nodes. However, that has not been our experience nor was it that of other investigators. Martin et al. [4] focused on this issue and they did not find any significant correlation between pathologic response and tumor size. Lu et al. [5] did not find clear differences when they stratified the nodes according to size and found only a marginal nonsignificant difference in tumors greater than 4 cm, with worse response. In other works there is no mention of any possible correlation between size and response [6, 7]. Concerning our own series, we can clarify that the aimed treatment volume was always greater than the lesion volume. Also, the procedure was performed with curative intent despite all the patients being candidates for transplant because of the uncertainty of how long they would be on the waiting list. The proportion of cases with tumors in the vicinity of large vessels was similar in patients with a tumor either smaller or larger than 3 cm in diameter. We have no explanation for this lack of correlation between pathologic response and node diameter, and we do not want to speculate. We admit, however, that a larger sample could show some difference, but for now we cannot change our conclusion that radiofrequency cannot be considered to be a radical or curative intent. This does not mean that radiofrequency is not useful, although it achieves only partial responses, because its use allows patients to stay on the transplant waiting list [8] and to reach long survival times without other therapies [9]. Finally, the American Association for the Study of Liver Disease recommendations [10] state that local ablation is safe and effective therapy for patients who cannot undergo resection is a bridge to transplantation. However, this statement does not imply that local ablation procedures can be considered as radical treatments.