Radiofrequency ablation, a minimally invasive treatment that applies heat directly to the tumor causing cancer cell death with minimal associated injury to the surrounding healthy liver, contributes to the prolongation of patients' lives by nearly three years, according to a study presented at the Society of Interventional Radiology's (SIR) 35th annual scientific meeting in Tampa, Fla. this week.
"Patients who have recurrent colon cancer in their liver after surgery can be treated with radiofrequency ablation, and avoid repeated liver surgery," said Constantinos T. Sofocleous, MD, PhD, an interventional radiologist at Memorial Sloan-Kettering Cancer Center in New York City.
“Radiofrequency ablation kills target cancer tissue with heat, while sparing the healthy tissue. This is particularly important for patients who develop new colon cancer in the liver after prior surgery. In general, these patients have a smaller amount of liver tissue; another surgery is usually not possible or very difficult and associated with higher risk," added Sofocleous.
Sofocleous and colleagues treated 56 patients with 71 hepatic colorectal metastases using CT guided radiofrequency ablation between December 2002 and December 2008 and the median overall survival was found to be 31 months. One-, two- and three-year overall survival rates were 91 percent, 66 percent and 41 percent respectively.
“More importantly, these survival rates—or life extensions—are in addition to the patients' survival rates after surgery," added Sofocleous.
A modified clinical risk score was used by the researchers to analyze the correlation with survival and local tumor progression according to nodal status of the primary cancer, interval from primary to liver metastases and number of tumors and size of the largest tumor ablated. Patients with tumor characteristics having two or less of these risks factors had the best outcomes. Researchers also evaluated the influence of hepatic artery infusion chemotherapy on local disease and overall survival.
Fifty-one percent of the lesions progressed within one to 27 months after ablation, according to Sofocleous and colleagues. The group that received pump chemotherapy did not reach the median survival, while the group with no prior pump treatment had a median survival of 25 months. Median time for local tumor progression was 14 months in pump group and 10 months in no pump group, according to researchers.
Radiofrequency ablation can be successfully used to treat colorectal cancer liver metastases and salvage surgical recurrences. Good patient selection (low clinical risk score) and arterial chemotherapy are associated with best clinical outcomes, concluded Sofocleous.