Initial institutional experience of uncooled single-antenna microwave ablation for large hepatocellular carcinoma.
OBJECTIVE
To evaluate the safety, efficacy, and feasibility of a novel microwave generator, designed to deliver automatically adjusted energy by tissue permittivity feedback control into the tumour via an uncooled antenna, in patients with larger hepatocellular carcinoma (HCC).


METHODS
Fourteen patients with HCC >5 cm in diameter received surgical or percutaneous microwave ablation with more than 12 months of follow-up. Microwave ablation was performed using a 902-928 MHz generator at 28 W; a single 14 G antenna without water-cooled system was used. The patients were followed up with contrast-enhanced CT and serum alpha-foetoprotein to monitor for tumour recurrence at 1 month and then every 3 months after tumour ablation.


RESULTS
The follow-up duration for the 11 male and three female patients (mean tumour size 5.77 cm, range 5-7 cm; mean age 63.8 years) was 15.8 months. The mean ablation time was 2025 s (range 900-3600 s), and the mean ablation session was 2.5 (range 1-4). The complete ablation rate was 85% (17 of 20). Local recurrence rate was 5.8% (1 of 17). All patients survived and the morbidity and mortality rate was 21.4% and 0%, respectively.


CONCLUSIONS
Microwave tissue ablation using this novel system with tissue permittivity feedback control and a single uncooled antenna has a high complete ablation rate and lower morbidity. It proved to be a fast, easy, and effective option for ablation of large (>5 cm) tumours.
Department of Medical Imaging, National Taiwan University Hospital, Taiwan; Institute of Biomedical Engineering, National Taiwan University, Taiwan.
P-C
PC
Liang
Department of Surgery, National Taiwan University Hospital, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taiwan.
H-S
HS
Lai
Department of Medical Imaging, National Taiwan University Hospital, Taiwan.
T T-F
TT
Shih
Department of Medical Imaging, National Taiwan University Hospital, Taiwan.
C-H
CH
Wu
Department of Surgery, National Taiwan University Hospital, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taiwan; Hepatitis Research Center, National Taiwan University Hospital, Taiwan. Electronic address: skywing@ntuh.gov.tw.
K-W
KW
Huang
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008872:Microwaves / Q000627:therapeutic use*; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D003287:Contrast Media