Percutaneous microwave ablation of exophytic tumours in hepatocellular carcinoma patients: Safe or not?

Background & Aims To explore the long-term outcomes and safety of ultrasound-guided percutaneous microwave ablation ( MWA) of exophytic tumours in hepatocellular carcinoma ( HCC) patients. Methods One hundred and thirty-two patients with subcapsular HCC were enrolled in this retrospective study. These patients were divided into the exophytic group (n=71) and non-exophytic group (n=61) according to the location of the tumour(s). A special technology of puncture and ablation was performed to treat the exophytic tumours. The local tumour progression ( LTP), progression free survival ( PFS) and overall survival ( OS) were analysed using Kaplan-Meier and Log-rank tests. Results Sixty-nine of 71 exophytic tumours and 60 of 61 subcapsular tumours were completely ablated. The complete ablation rates were 97.2% and 98.4% respectively. The follow-up periods ranged from 6 to 62 months with a median of 31 months in the exophytic group, and ranged from 5 to 61 months, with a median of 27 months in the non-exophytic group. The 1-, 3- and 5-year cumulative LTP rates were 2.4%, 12.3%, 18.4% and 5.1%, 12.0%, 17.8% in the exophytic and non-exophytic groups respectively ( P=.733). The 1-, 3- and 5-year OS rates were 100%, 75.7%, 52.9% and 95.0%, 73.8%, 61.5% in the exophytic group and non-exophytic group respectively ( P=.980). There was no procedure-related mortality or major complication. Conclusion Ultrasound-guided percutaneous MWA is safe and effective for exophytic tumours in HCC patients. Treated by MWA, the HCC patients with exophytic tumours can get the similar local response and long-term outcome to those with non-exophytic subcapsular tumours. [ABSTRACT FROM AUTHOR]