Safety and an Evolving Role in Treatment
Dr. Doppelt believes the team’s findings give radiologists and multidisciplinary teams a strong, contemporary safety reference when discussing curative therapy for small malignant liver neoplasms.
“For patients, the message is important: In modern practice, percutaneous thermal ablation is a minimally invasive treatment with a very low risk of major complications and extremely low procedure-related mortality,” he said.
Still, questions remain about how ablation fits into the broader treatment landscape. Evidence from prospective randomized trials on colorectal metastases and hepatocellular carcinoma suggests that thermal ablation can achieve outcomes comparable to surgery in select patients, particularly for small lesions. Michael A. Bettmann, MD, professor of radiology emeritus at Wake Forest University School of Medicine in Winston-Salem, NC, said the curative ability of the treatment remains unclear.
In a related editorial, Dr. Bettmann stated that surgery is the only therapeutic approach to hepatocellular carcinoma that may be considered curative. He added that the prognosis for both primary and metastatic liver cancer is poor overall, and that even surgery that involves resection or transplant yields a five-year survival rate of less than 50%.
“Thermal ablation is most logical, theoretically, for use with a limited number of lesions that originate in the target organ—in this case, the liver,” Dr. Bettmann explained. “If lesions are metastatic, ablation can be combined with other treatments, such as systemic medication.”
Further Clinical Trials Needed to Determine Best Use
Dr. Bettmann said that future research will almost certainly include a comparison of different methods: radiofrequency ablation, cryoablation, microwave ablation and US ablation.
“All have shown considerable efficacy, but there are so many variables that it is very hard to reach firm conclusions,” Dr. Bettman said. “Further, ablation is rarely used alone. Determining how to best use it in conjunction with radiation, arterial embolization techniques or—most importantly—targeted systemic therapy will be the major focus of clinical research.”
Dr. Doppelt agrees that future clinical trials need to examine how radiologists can combine ablation with systemic therapies such as immunotherapy.
“If we know the baseline safety profile of ablation itself, it becomes much easier to interpret adverse events in combination studies and to design future trials more rigorously,” he concluded.
For More Information
Access the Radiology study, “The Safety Standards for Liver Percutaneous Thermal Ablation: A Meta-Analysis of Adverse Events over 15 Years,” and the related editorial, “Ablation of Liver Malignancies Is Safe: Does This Fully Define Its Role?”
Read previous RSNA News articles on thermal ablation: