My colleagues and I read with great interest the article by Livraghi et al., where the authors stated that radiofrequency ablation (RFA) could be considered the treatment of choice for patients with a singe hepatocellular carcinoma ≤ 2 cm, even when surgical treatment is possible.1 We agree with the main conclusion of the authors. As the authors have pointed out, RFA seems to be equivalent to surgery in terms of local disease control and survival.1 In addition, RFA is generally much less invasive than surgery and is associated with a lower complication rate.2 It is no longer unusual that RFA can be the treatment of choice for patients with a single small hepatocellular carcinoma nodule. The investigators must be congratulated for their difficult work.
However, we have a question concerning the statistical analysis. In the study, multivariate analysis demonstrated that the appearance of one or more new lesions was the only statistically significant factor. However, the appearance of any new lesion is a delayed phenomenon after RFA. We think that prognosis prediction based on a delayed phenomenon would be of little value in treatment planning and survival prediction at the initial stage of interventional management. We would like to know the results of multivariate analysis after exclusion of this factor. After the exclusion, other factors such as operability might become statistically significant as determined by multivariate analysis.