Saline-linked surface radiofrequency ablation: a safe and effective method of surface ablation of hepatic metastatic colorectal cancer.
OBJECTIVE
To determine the safety and efficacy of saline-linked surface radiofrequency ablation (SLSRFA) in a clinical setting.


BACKGROUND
We have previously identified safe and effective parameters for use of SLSRFA in a porcine model.


METHODS
An initial study was conducted to determine if parameters defined in the porcine model were safe and effective in human livers. In 16 patients undergoing liver resection, normal areas of liver were treated with SLSRFA using various power/diameter combinations (10 W/1 cm; 15 W/2 cm; 45 W/4 cm) for 9 minutes with and without inflow occlusion. In a second study, superficial hepatic colorectal cancer (CRC) metastases were treated at 45 W/4 cm for 9 minutes without inflow occlusion in 11 patients. Ablation depth was measured and samples were examined for cell viability by nicotine adenine dinucleotide stain. This study was registered in the ClinicalTrials.gov database and has the following ID number, NCT00869843.


RESULTS
Ablation depth in normal liver varied from 3 to 20 mm. Depth was significantly dependent on power, lesion size, and inflow occlusion. Nicotine adenine dinucleotide stains showed total cell necrosis to the full depth of ablation. In the second study, large hepatic CRC metastases showed total cell necrosis to a mean depth of 12 mm. Two tumors less than 7 mm in depth showed complete necrosis. Metastases were more susceptible to SLSRFA than normal liver.


CONCLUSIONS
SLSRFA completely and safely ablates normal liver to a depth of at least 4 mm at 45 W/4 cm treatment parameters. Remarkably, it is even more effective in ablating metastatic CRC. SLSRFA is an effective tool for extending resection margins and for ablating superficial small tumors or superficial parts of large tumors.
Gnerlich
Jennifer L
JL
Section of Hepatobiliary-Pancreatic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, Missouri, USA.
Ritter
Jon H
JH
Linehan
David C
DC
Hawkins
William G
WG
Strasberg
Steven M
SM
D000818:Animals; D017115:Catheter Ablation / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology*; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D008099:Liver / Q000473:pathology / Q000601:surgery; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary / Q000601:surgery*; D023421:Models, Animal; D012965:Sodium Chloride / Q000008:administration & dosage; D013552:Swine; D016896:Treatment Outcome
D012965:Sodium Chloride