Radiofrequency ablation (RFA) has emerged as a promising therapy for patients with small lung tumors and is becoming another option for patients unable to undergo surgical resection or who have not responded to other therapies. It can also be used as a complementary treatment with chemotherapy and radiation therapy.
A minimally invasive technique, RFA (see CURE, Spring 2005) has fewer side effects and a quicker recovery time than chemotherapy or resection surgery. RFA was initially used for patients with tumors that had spread to the liver, but it is now also being used for lung tumors as well as tumors in the adrenal glands and other sites.
During the procedure, a small incision is made to allow the surgeon to insert a needle that is guided by CT or ultrasound. Once the needle reaches the tumor, the tip expands to an umbrella shape to reach more surface area of the tumor (see illustration). Radiofrequency waves cause heating of the tissue’s molecules and raises its temperature to as high as the boiling point of water. This heat causes the cells around the radiofrequency probe to die.
As the needle is withdrawn after the procedure, low-energy radiofrequency waves are used along the needle track to minimize the risk of bleeding. Because the heating process can be painful, patients are treated under light sedation or monitored anesthesia. Patients may need pain medication for a couple of days after the surgery. Side effects can include bleeding, infection and, on rare occasions, air leakage from the lungs, which can cause collapsing of the lung tissue.
RFA has mainly been used in lung cancer patients with small lesions located in the periphery of the lung, but it also being studied in breast, prostate and kidney cancers. Early clinical studies with RFA for small lung tumors (less than 4 cm) have shown a high rate of complete response—encouraging news for a cancer that claims over 160,000 lives a year. However, since this therapy is relatively new for lung cancer, little follow-up data exists regarding long-term survival and recurrence.
Researchers hope to conduct a clinical trial soon that will directly compare RFA with other treatments to better understand how well RFA works against traditional therapies.