Reuters Health Information (2011-11-18): Is radiofrequency ablation as good as surgery for HCC up to 4cm?
Is radiofrequency ablation as good as surgery for HCC up to 4cm?
Last Updated: 2011-11-18 17:50:22 -0400 (Reuters Health)
NEW YORK (Reuters Health) - Hepatocellular carcinoma patients who underwent radio frequency ablation (RFA) had a similar survival rate to those who had a surgical resection in a new study from China.
There was no difference in survival even for tumors up to 4cm in diameter, researchers reported November 7th at the annual meeting of the American Association for the Study of Liver Diseases in San Francisco.
The abstract was one of 10 that Dr. Jake Liang, president of the AASLD, singled out to present to the media from among 2300 abstracts at the conference. But at least one expert said the study can't definitively answer the question of whether ablation is as good as surgery for this kind of cancer.
The trial was headed by Dr. Ma Kuansheng at Southwest Hospital in Chongqing. The researchers randomly assigned 168 patients with early-stage hepatoma to either surgery or RFA. Each patient had no more than two tumors less than 4cm in diameter.
Survival rates were similar: 96% in the surgery group and 93.1% in the RFA group at one year, 87.6% with surgery and 83.2% with RFA at two years, and 74.8% and 67.6%, respectively, at three years.
Predictors of survival after ablation included multiple tumors (relative risk 3.85, p = 0.018) and preoperative indocyanine green clearance (RR 3.544, p = 0.002).
Dr. Yuman Fong, a hepatobiliary surgeon at Memorial Sloan-Kettering Cancer Center in New York City who was not involved in the research, pointed to a growing body of research suggesting that ablation compares to surgery for small carcinomas. In that context, the finding is not surprising, but welcome, he told Reuters Health.
"This is an important finding because most patients with HCC have cirrhosis and cannot have a liver resection," Dr. Fong said. "Ablation therefore becomes a life saving, safe and effective therapy for these patients."
But Dr. Myron Schwartz, a surgical oncologist at the Mount Sinai Hospital in New York City, warned of flaws in the study's design.
He told Reuters Health that as a reviewer for the AASLD he had read the abstract when it was first submitted. Among the study's problems, he said, is that it appears to contradict a larger body of evidence suggesting that the failure rate for ablation increases with the size of the tumor.
"It is well-documented that local failure of RFA increases rapidly with increasing tumor diameter," he wrote in an email. "Failure at 2cm is around 5%, whereas at 4cm it's as high as 40%."
Also, he suspects that some of the patients randomized to surgery may not have been good candidates for the procedure.
Resection patients should have normal liver function (including normal ICG clearance) and no portal hypertension, he said. "The fact that impaired ICG clearance was an independent risk factor for poor outcome in this study allows one to conclude that patients with impaired ICG clearance were allowed to enter the study."
Furthermore, according to Dr. Schwartz, patients with multiple tumors are not optimal resection candidates "since multiple tumors imply intrahepatic dissemination and a high likelihood of remote recurrence regardless of how the index tumors are treated."
"The bottom line is that this trial adds nothing," Dr. Schwartz said.
"The real question," he added, "which hasn't been answered directly by a randomized trial but on which a consensus seems to be building, is whether ablation is equivalent to resection even for optimal resection candidates when there is a solitary hepatocellular carcinoma of 2cm or less in diameter."
"The answer seems more and more to be, Yes," Dr. Schwartz said. He added that guidelines are starting to reflect that agreement, "and it's what we do these days."