Ablation for Hepatocellular Carcinoma: Where Do We Stand?
We thank Drs Li and Wen for their comments on the article we recently published in Annals of Surgery.1 They pointed out several issues that could be incorporated into our article, and we would like to specifically address these points.
The diagnosis of hepatocellular carcinoma (HCC) for patients receiving radio frequency ablation (RFA) was confirmed by biopsy sample obtained during RFA procedure or according to the HCC consensus guidelines put forward by the European Association for the Study of the Liver and American Association for the Study of Liver Diseases. Therefore, we did not have tissue samples for all of the RFA patients, and the impact of pathological features on patients’ survival could not be performed. Aside from tumoral factors, cirrhosis is another important risk factor for HCC recurrence. Indeed, a variable proportion of patients with HCC do not actually have cirrhosis. However, the Child-Turcotte-Pugh (CTP) classification system initially designed for predicting prognosis in patients with cirrhosis is still widely implemented in HCC staging systems. In this study, 181 patients were CTP class A5, whereas 56 patients were CTP class A6. Recently, the albumin-bilirubin (ALBI) grade was proposed to assess the degree of liver dysfunction for patients with HCC.2 According to the ALBI grade, 133 patients in the study were ALBI grade 1, whereas 104 patients were classified as ALBI grade 2. There are no significant differences between distribution of CTP class A5/A6 or ALBI grade 1/2 in patients receiving SR or RFA, both in all patient analysis, and in patients selected in the propensity model.
Local recurrence was defined as local tumor progression at or adjacent to the ablation site after single RFA session in this study. It should be noted that the definitions of local recurrence varied between studies. In a recently published real-world study, patients who had contrast enhancement after initial ablation were considered as those with incomplete ablation rather than local recurrence.3 These different definitions regarding incomplete treatment and local recurrence, and diverse treatment strategies for patients with incomplete treatment, should be taken into consideration when comparing RFA results from different study groups.
The ablative technique employed in the current study was percutaneous RFA. Open surgical or laparoscopic ablation seems to be promising therapeutic for patients with HCC. Open surgical ablation may achieve similar survival rates while offering better cost benefits and risk profiles than surgical resection.4 Laparoscopic tumor ablation was also reported as being safe and feasible with excellent therapeutic efficacy.5 Indeed, both surgical procedures and ablative techniques have witnessed enormous advancements. Microwave ablation, cryoablation, and laser ablation are emerging tools for local control of HCC.6 Meanwhile, clinical trials providing pairwise comparison between conventional surgical resection and various types of ablation are still lacking. Hopefully, these improvements can eventually translate into better long-term survival for patients with HCC.