Thermal ablation effective in early-stage lung cancer

Thermal ablation conferred OS rates comparable to those of stereotactic radiation therapy among patients with inoperable, stage I non-small cell lung cancer, according to study results.

Stereotactic radiotherapy is a common treatment option for patients with lung cancer who are unable to undergo surgery. However, radiation can harm healthy tissue and is associated with risk for toxicities.

“Thermal ablation is most often a one-time treatment, unlike stereotactic radiotherapy, which requires multiple visits,” Hyun S. “Kevin” Kim, MD, professor of radiology and medical oncology at Yale Cancer Center at Yale School of Medicine, chief of interventional radiology at Yale New Haven Hospital, and program leader of interventional oncology at Smilow Cancer Hospital, said in a press release. “In addition, thermal ablation delivers highly accurate and precise localized treatment targeted to cancer cells, minimizing the effects to surrounding tissue and keeping toxicities low.”

Kim and colleagues conducted a retrospective study of 28,834 patients with inoperable, stage I NSCLC included in the National Cancer Database between 2004 and 2013. Patients underwent thermal ablation (n = 1,102) or stereotactic radiation therapy (n = 27,732) and were one-to-one propensity matched to undergo thermal ablation.

OS and unplanned hospital readmission within 30 days after treatment served as primary endpoints.

After mean follow-up of 52.4 months, researchers observed no significant differences in OS between the two treatment groups. However, unplanned hospital readmission rates were higher among patients who underwent thermal ablation (3.7% vs. 0.2%).

HemOnc Today spoke with Kim about the need for alternative treatment strategies for patients with early-stage lung cancer who are not candidates for surgery, how the study was conducted, and whether more research is needed to confirm the role of thermal ablation for this patient population.

Question: Can you explain the need for alternative treatment strategies for patients with early-stage lung cancer who are not candidates for surgery?

Answer: There are so many patients who are diagnosed with lung cancer. Although mortality rates have improved due to smoking cessation, early screening programs and excellent treatment options, the sheer number of deaths remains staggering in the United States. Not every patient can undergo surgery due to many factors, including lung function, age or other comorbidities. At the present time, there are two treatment strategies offered for these patients — radiotherapy and thermal ablation. However, there are benefits and downsides to both.

Q: What did you find?

A: After comparing OS rates between patients assigned radiotherapy and thermal ablation, the short-, mid- and long-term survival rates were similar. The Kaplan-Meier curves were quite similar, if not almost identical. At 1 year, OS was 85.4% with thermal ablation vs. 86.3% with stereotactic radiation therapy; 2-year OS was 65.2% with thermal ablation vs. 64.5% with stereotactic radiation therapy; and 3-year OS was 47.8% with thermal ablation vs. 45.9% with stereotactic radiation therapy.

Q: How might patients benefit from these findings ?

A: Both therapies are not necessarily offered at every hospital in the United States, and patients, based on personal circumstances or needs, may prefer one therapy over another. It is very helpful to know that both treatments are equally effective.

Q: What are the potential advantages of thermal ablation therapy?

A: One of the benefits of thermal ablation treatment is access to the tissue. A small probe, under image guidance, is placed directly into the cancer. We typically do the biopsy at the same time as ablation; therefore, it reduces the number of treatment encounters as well as the number of times a patient has to travel to the hospital. This reduces costs and is more convenient for the patient, as the diagnosis and treatment all occur at the same time.

Q: Is more research needed to confirm the role of thermal ablation for this patient population , or should this approach be adopted immediately as a viable treatment strategy?

A: Thermal ablation is available in many hospitals across the country for multiple applications, including liver cancer, spine tumors or bone tumors. However, there has not been a large-scale randomized trial in a head-to-head comparison to assess this approach. Still, both are effective therapies for these patients, and this study adds more data to confirm this.

Q: Is there anything else that you would like to mention?

A: Thermal ablation could potentially benefit a lot of patients, as well as health care in general, in the United States. In addition, there is huge potential for thermal ablation modulating a positive immune response when used with immunotherapies. In the future, treatment strategies that incorporate local therapy — such as thermal ablation — with systemic therapies may be effective in later-stage lung cancer, as well. – by Jennifer Southall

Reference:

Uhlig J, et al. Radiology. 2018;doi:10.1148/radiol.2018180979.

For more information:

Hyun S. “Kevin” Kim, MD, can be reached at Yale School of Medicine, 333 Cedar St., P.O. Box 208042, New Haven, CT 06520-8028; email: kevin.kim@yale.edu.

Disclosure: Kim reports no relevant financial disclosures.