Radio-Frequency Ablation of Focal Tumors
I. Overview
Radio-frequency ablation is a minimally invasive treatment for focal cancers (cancers limited to one area of the body). Radio-frequency ablation destroys tumors with localized heat from electrical energy. After the patient has been sedated, the physician inserts a special needle through the skin. (Unlike a catheter, the instrument does not travel through a blood vessel.) Using CT or ultrasound imaging technology, he or she maneuvers this instrument into the tumor and activates an electrical circuit that generates intense but localized heat. Because the heat is generated within the tumor, surrounding healthy tissue is mostly spared.
This procedure can be performed under local anesthesia but is usually performed under general anesthesia, to eliminate the possibility of pain during treatment. Patients generally stay in the hospital overnight, but many go home the same day. They can usually return to work in one or two days. Side effects include soreness at the site of the puncture. Rarely, the puncture site can bleed. If heat is released near the diaphragm (which divides the stomach from the chest cavity), the treatment can occasionally cause hiccupping that lasts several weeks.
II. Medications
General anesthesia is administered during the procedure. Pain medications may be given afterward.
III. Considerations
Patients with focal tumors who are not eligible for surgical resection (removal of the tumors) should consider this treatment. Very large tumors (those greater than 4 centimeters in diameter) can be difficult to treat fully with this technique. Determining which treatment is right for an individual patient is a complex process requiring consultation with many different specialists.
IV. Effectiveness
The efficacy of radio-frequency ablation varies with tumor type, size, and location. The technique has outcomes similar to those of surgical resection for appropriately selected tumors. In one study of radio-frequency ablation for liver tumors, 94 percent of primary tumors (those originating from within the cancerous organ) had not grown back 10 months after being destroyed by the treatment. Radio-frequency ablation can be used in combination with chemoembolization for liver tumors, which may further improve the outcome. (Radio-frequency ablation can penetrate to the center of tumors, while chemoembolization is most effective on the outside of tumors.) One study showed only a 2 percent recurrence of primary liver tumors one year after such a combination therapy. For background on liver cancer and the range of treatments available, see the E-Health article on chemoembolization, as well as this article about the multidisciplinary Liver Tumor Clinic at UW Medical Center. (Radio-frequency ablation is also used to treat cancers in organs other than the liver.)
V. Risks of Treatment
In addition to the rare side effects mentioned above (bleeding and hiccupping), there is a small risk in undergoing general anesthesia.
VI. Risks of No Treatment
Focal tumors that receive no treatment are likely to grow and spread. Depending upon tumor type and location, such progression can lead to significant complications or death. With treatment, the risk of progression may be reduced.
VII. Urgency
Cancer should be treated as soon as possible.
