To analyze the learning curve of hepatocellular carcinoma ablation assisted by a real-time image virtual navigation system (RVS).

Sixty patients with hepatocellular carcinoma who underwent tumor ablation assisted by a RVS by the same physician, who had 5 years of experience in ablation, at Hangzhou Xixi Hospital Affiliated to Zhejiang Chinese Medicine University from October 2018 to September 2019 were analyzed retrospectively. According to the treatment order, the patients were divided into groups A, B, and C, with 20 cases in each group. The difference in preoperative RVS fusion time and tumor ablation time among groups was compared by ANOVA, and pairwise comparisons between groups were performed by LSD-t test; Fisher's exact probability method was used to analyze the difference in the success rate of one-time tumor ablation and the complete tumor inactivation rate one month after surgery between the patient groups. RVS preopreative fusion time curve was plotted to assist liver cancer ablation.

The preoperative fusion time and tumor ablation time of RVS in group A were significantly longer than that in group B and group C [(20.9±6.7) min vs (9.7±1.2) min vs (9.6±2.7) min, t=7.4, P＜0.001; (23.1±7.9) min vs (19.6±5.0) min vs (19.2±3.7) min, t=1.9, P=0.035]); there were no statistically significant difference between group B and group C (P＞0.05). The success rate of one-time tumor ablation in group A [74.1% (20/27)] was significantly lower than those of group B [96.4% (27/28)] and group C [96.4% (27/28)] (P=0.025), although there was no statistically significant difference between group B and group C (P＞0.05). There was no significant difference in the complete tumor inactivation rate one month after tumor ablation among the three groups [92.6% (25/27) vs 92.9% (26/28) vs 92.9% (26/28), P＞0.05]. After the operator accumulated about 20 patients, the pre-operative fusion time tended to stabilize and the learning entered the platform period.

For interventional physicians who are expected to be proficient in hepatocellular carcinoma ablation assisted by a RVS, the accumulated number of patients treated by the operator is about 20, in order to significantly shorten the preoperative fusion time and tumor ablation time, improve the fusion accuracy, team fit, and the success rate of one-time tumor ablation, and make the learning curve enter the plateau stage.