Percutaneous Image-guided Radiofrequency Ablation Research Articles

Image-guided radiofrequency ablation of renal cell carcinoma

The incidence of renal cell carcinoma is rising with the increased number of incidental detection of small tumours. During the past few years, percutaneous imaging-guided radiofrequency ablation has evolved as a minimally invasive treatment of small unresectable renal tumours offering reduced patient morbidity and overall health care costs. In radiofrequency ablation, thermal energy is deposited into a targeted tumour by means of a radiofrequency applicator. In recent studies, radiofrequency ablation was shown to be an effective and safe modality for local destruction of renal cell carcinoma. Radiofrequency applicator navigation can be performed via ultrasound, computed tomography or magnetic resonance guidance; however, ultrasound seems less favourable because of the absence of monitoring capabilities during ablation. On-line monitoring of treatment outcome can only be performed with magnetic resonance imaging giving the possibility of eventual applicator repositioning to ablate visible residual tumour tissue. Long-term follow-up is crucial to assess completeness of tumour ablation. New developments in ablation technology and radiological equipment will further increase the indication field for radiofrequency ablation of renal cell carcinoma. Altogether, radiofrequency ablation seems to be a promising new modality for the minimally invasive treatment of renal cell carcinoma, which was demonstrated to exhibit high short-term effectiveness.

Renal Tumors: Technical Success and Early Clinical Experience with Radiofrequency Ablation of 18 Tumors

To evaluate the feasibility, safety, and technical efficacy of image-guided radiofrequency ablation (RFA) for the treatment of small peripheral renal tumors and to report our early results with this treatment modality. Twenty-two RFA sessions for 18 tumors were performed in 11 patients with renal tumors. Indications included coexistent morbidity, high surgical or anesthetic risk, solitary kidney, and hereditary predisposition to renal cell carcinoma. Ten patients had CT-guided percutaneous RFA performed on an outpatient basis. One patient had open intraoperative ultrasound-guided RFA. Technical success was defined as elimination of areas that enhanced at imaging within the entire tumor. With the exception of one patient with renal insufficiency who required gadolinium-enhanced MRI, the remaining patients underwent contrast-enhanced CT for post-treatment follow-up assessment. Follow-up was performed after 2-4 weeks and then at 3, 6, 12 months, and every 12 months thereafter. Fourteen (78%) of 18 tumors were successfully ablated with one session. Three of the remaining four tumors required two sessions for successful ablation. One tumor will require a third session for areas of persistent enhancement. Mean patient age was 72.82 +/- 10.43 years. Mean tumor size was 1.95 +/- 0.79 cm. Mean follow-up time was 10.91 months. All procedures were performed without any major complications. Our early experience with percutaneous image-guided radiofrequency ablation demonstrates it to be a feasible, safe, noninvasive, and effective treatment of small peripheral renal tumors.

Image-guided Percutaneous Radiofrequency Ablation and Incidence of Post–Radiofrequency Ablation Syndrome: Prospective Survey

To evaluate prospectively the incidence of post-radiofrequency (RF) ablation syndrome and determine its impact on the quality of life in the 10 days after percutaneous RF ablation. This study was approved by the institutional review board and was HIPAA compliant. Informed consent was obtained for this survey in all patients by the interventional nurse coordinators. Thirty-six patients (20 men, 16 women; mean age, 69.3 years; range, 40-88 years) underwent RF ablation for 26 liver tumors and 17 renal tumors. Twenty control patients (11 men, nine women; mean age, 60.8 years; range, 35-76 years) underwent biopsy of focal liver lesions or renal lesions. With a standardized questionnaire, a telephone survey was conducted on days 1, 3, 5, and 10 after RF ablation or biopsy. The symptoms and interference with lifestyle were documented prospectively with a numeric intensity scale by using grades 0-10. Statistical analysis with Fisher exact test and analysis of variance was performed. After RF ablation, 15 (42%) patients developed low-grade fever (P < .001), 29 (81%) had flulike symptoms (P < .001), and four were asymptomatic. Symptoms peaked on day 3 and mainly resolved by day 10. Twelve (33%) patients had complete post-RF ablation syndrome: fever and flulike symptoms (P = .005). Flulike symptoms were more prolonged when they were accompanied with fever, peaked on day 5, and resolved more quickly for patients with renal lesions than they did for patients with liver lesions. Four patients had persistent fever caused by pneumonia (n = 2), pleural effusion and atelectasis (n = 1), or liver abscess (n = 1). No control patients developed both fever and flulike symptoms. Post-RF ablation patients with symptoms experienced significantly greater pain and interference with general and work activities, which peaked on day 1, than did control patients (P = .01 [pain], P < .001 [general and work activities]). Complete post-RF ablation syndrome occurs in approximately one-third of patients but is self-limiting within 10 days after the procedure. Persistent or late-onset fever may indicate concurrent infection elsewhere or possible abscess formation. radiology.rsnajnls.org/cgi/content/full/237/3/1097/DC1

Radiofrequency ablation of lymphoma

6710 Background: The role of radiofrequency ablation (RFA) for the treatment of lymphoma is undocumented. We present three patients in whom RFA was used, for three different indications, to treat residual lymphomatous lesions unresponsive to conventional treatment. Methods: Three patients with isolated lymphoma masses were treated with percutaneous image-guided RFA. The first patient had a residual hepatic mass after EPOCH and rituximab chemotherapy for polymorphic post-transplant lymphoproliferative disorder. The second patient had a progressively enlarging follicular lymphoma adjacent to the bladder wall following prior maximum radiation therapy and CHOP chemotherapy and was treated with RFA for pain palliation. In the third case, the patient had a rapidly enlarging B-cell lymphoma of the right neck causing impending airway compromise. The water-cooled Radionics generator ablation system was used with a cluster needle probe in all cases. Impedence, temperature, power, current, and time were monitored closely. Patients were followed both clinically and with CT, MRI, or PET to evaluate for treatment response and/or recurrence of their lesions. Results: Following RFA, the first patient had complete radiological resolution of the hepatic masses and remains disease free at four years post-treatment. The second patient achieved a partial response to the pelvic mass, requiring a second ablation treatment for recurrent urinary symptoms. He remained with improved symptoms at most recent follow-up. Although the third patient had short-term relief of his neck pain and respiratory compromise post-ablation, he expired five weeks later from his lymphoma. Conclusions: These cases of chemoresistance, pain palliation, and pending airway compromise illustrate settings in which RFA may be a preferable treatment to radiation or surgery, producing potentially less morbidity than standard treatments. Previous studies have shown that RFA produces a robust inflammatory response and could lead to a boost in the immune response against lymphoma, especially when performed with costimulatory agents like vaccines or other immunostimulation. This study exemplifies ways in which RFA may help manage patients with lymphoma and few alternative therapies. No significant financial relationships to disclose.

CT-guided radiofrequency ablation of pediatric Wilms tumor in a solitary kidney

Although recent results of percutaneous imaging-guided radiofrequency ablation (RFA) of various tumors in adults are promising, RFA of tumors in children has been performed in only a small number of cases. We describe the treatment of Wilms tumor in a solitary kidney in a 5-year-old girl using percutaneous CT-guided RFA. The procedure provided short-term palliation in this child for whom partial or total nephrectomy carried high risk and low likelihood of success. Although it might only be useful ultimately as a temporizing measure, oncologists and surgeons might wish to consider RFA in children who would otherwise require dialysis and renal transplantation or who are poor surgical candidates. Various specific technical issues differentiate pediatric from adult tumor ablation, including the amount of intra-abdominal fat, need for smaller grounding pads, and potential systemic effects of tissue heating.

Combination treatment of vertebral metastases using image-guided percutaneous radiofrequency ablation and vertebroplasty: a case report

Background We describe a case of vertebral metastases treated with a combination of percutaneous radiofrequency ablation (RFA) and vertebroplasty in a single session. Case Description A 45-year-old female with recently diagnosed metastatic non-small cell lung cancer was referred for consideration of vertebroplasty after having several weeks of back pain. Computed tomography and magnetic resonance imaging scans of the thoracic spine revealed metastatic lesions at the T9 and T12 bodies. Radiofrequency ablation was performed using a starburst array electrode (Rita Medical Systems, Mountain View, Calif). The metastatic lesion in the T9 vertebral body measured 1.5 × 1.5 cm and was heated to 100°C for 5 minutes. Vertebroplasty was then performed on this lesion as well as a lesion at T12 with no complications. The patient was discharged home the same day without complaints. Conclusion Radiofrequency ablation and vertebroplasty are minimally invasive procedures that can be used in combination to treat spinal metastases. The pain relief from these treatments is often immediate. RFA can also be used to minimize procedure-related complications during the vertebroplasty. In properly selected patients, RFA may also increase the duration of local spinal stabilization afforded by the vertebroplasty alone. Long-term studies are warranted to assess the efficacy and durability of this unique approach.

Percutaneous Radiofrequency Ablation of Renal Cell Carcinoma

Preliminary data regarding the use of percutaneous radiofrequency ablation (RFA) for the treatment of renal cell carcinoma (RCC) are encouraging, and show the technique to be associated with minimal morbidity. Thus, the current study was designed to evaluate the clinical applications, treatment efficacy, and complications of percutaneous RFA in RCC. From February 2003 to February 2004, 12 consecutive patients with histopathologically proven RCC underwent imaging-guided percutaneous RFA. The mean age of the patients (8 men and 4 women) was 76 years (range, 56-87 years), and mean tumor diameter was 3.7 cm (range, 2.2-8.0 cm). The efficacy of RFA was evaluated with contrast-enhanced, dynamic computed tomography (CT) performed 1 month after treatment, and then every 3 months. A Radionics device with an internally cooled electrode was used in 7 patients, and a radiofrequency interstitial tissue ablation (RITA) device with an expandable needle electrode was used in 5. Complete necrosis was defined as a lack of contrast enhancement in the treated region on follow-up CT studies. Overall, 16 sessions of RFA were performed for 12 solitary renal tumors in 12 patients: 8 patients underwent a single RFA session, whereas 4 had 2 sessions. Dynamic CT after RFA showed complete necrosis in 9 of 12 tumors. In 3 patients with tumors of 4.5-8.0 cm in diameter, enhancement of residual tissue was observed after RFA treatment, thus indicating residual tumor. Complete tumor necrosis was seen in all 5 tumors (100%) of diameter < or = 3.0 cm; 3 of 4 tumors (75%) of diameter 3.1-5.0 cm; and 1 of 3 tumors (33%) of diameter > 5.0 cm. A big subcapsular hematoma, which was found in 1 patient after RFA, resolved completely within 10 months without treatment; no serious complications occurred in the other 11 patients. Percutaneous RFA is effective in the treatment of RCC. It is most successful for tumors not larger than 3 cm in diameter, and has a satisfactory success rate in tumors of 3-5 cm in diameter. The rate of serious complications of RFA is low. Further studies are necessary to determine the long-term efficacy of RFA in RCC.

Radiofrequency Ablation of Thoracic Lesions: Part 2, Initial Clinical Experience—Technical and Multidisciplinary Considerations in 30 Patients

The purpose of our study was to report our initial experience with patients who underwent percutaneous imaging-guided radiofrequency ablation of thoracic lesions, and to emphasize technical and multidisciplinary issues and adjunctive procedures specific to thoracic tumor ablation. Our cohort consisted of 30 patients with a spectrum of primary (n=18) and secondary (n=11) lung tumors, mesothelioma (n=1), and five secondarily eroded, painful ribs who underwent ablation of 36 total lesions (one patient had two ablations). Patients either were nonsurgical candidates because of medical comorbidities or extent of disease, or had exhausted chemotherapy and radiation therapy options, or had refused surgery or undergone unsuccessful surgery. Patients were treated with radiofrequency ablation after agreement among oncologists, thoracic surgeons, and interventional radiologists. An array-style electrode under impedance control was used to treat 29 thoracic tumors and the adjacent rib metastases (n=5). A cool-tip radiofrequency probe was used for two patients. CT guidance and general anesthetic were used for all but one patient. Sonographic guidance and IV conscious sedation were used in one patient. Pain (n=11) and tumor cure or control (n=19) were the primary indications for the procedures. Adjunctive procedures to the radiofrequency ablations included the creation of saline or water windows (n=3); establishment of transosseous and transchondral routes (n=4); use of intercostal and paravertebral nerve blocks (n=15); and use of an intraprocedural catheter (n=1), needle (n=1), or sheath (n=3) for treatment of pneumothoraces. Follow-up was from 2 to 26 months. All ablations were technically successful. No periprocedural mortality occurred. Necrosis of tumor was greater than 90% in 26 of 30 lesions based on short-term follow-up imaging (CT, PET, MRI). In the 11 patients who underwent ablation for pain, relief was complete in four and partial in the other seven. One patient developed a local skin burn, four patients had self-limited hemoptysis up to 4 days after ablation, one had transient atrial fibrillation, one developed hoarseness, and two patients were transiently reintubated after extubation. Eight pneumothoraces developed; one patient underwent placement of a chest tube. Four patients died within 1 year of ablation from extrathoracic spread of tumor. Radiofrequency ablation for a variety of thoracic tumors can be performed safely and with a high degree of efficacy for pain control and tumor killing. The effect of ablation can be assessed with CT, MRI, or PET. Various technical issues differentiate thoracic tumor ablation from standard abdominal ablations. Numerous other thoracic interventional radiology procedures are beneficial to assist the radiofrequency ablation. A multidisciplinary approach offers valuable expertise for patient care.

Early-Stage Hepatocellular Carcinoma in Patients with Cirrhosis: Long-term Results of Percutaneous Image-guided Radiofrequency Ablation

To perform a prospective, intention-to-treat clinical trial to determine the long-term survival rates of patients with hepatic cirrhosis and early-stage hepatocellular carcinoma (HCC) in whom percutaneous image-guided radiofrequency (RF) ablation was used as the sole first-line anticancer treatment. The study was performed with approval of the ethics committee, and written informed consent was obtained for all patients. From June 1, 1996, to January 1, 2003, 206 patients (143 men, 63 women; age range, 51-81 years; mean age, 67 years +/- 7) who were excluded from surgery and who had Child class A or B cirrhosis with either a single HCC less than or equal to 5 cm in diameter or multiple (as many as three) HCCs less than or equal to 3 cm in diameter each were enrolled. RF ablation was performed in 187 (91%) of 206 patients; 19 (9%) were excluded from RF treatment because of unfavorable tumor location. Follow-up ranged from 3 to 78 months (mean, 24 months +/- 21) and included measurement of alpha-fetoprotein level, ultrasonography at 3-month intervals, and spiral computed tomography at 6-month intervals. Patients were observed for recurrence of the treated tumor and for the emergence of new HCC tumors. Survival probabilities were estimated with the Kaplan-Meier method, and differences between survival curves were evaluated with the log-rank test. At the end of the study, 145 patients were alive, and 61 were dead. In the intention-to-treat analysis, overall survival rates were 97% at 1 year, 67% at 3 years, and 41% at 5 years. Median survival was 49 months. In the 187 patients treated with RF ablation, overall survival rates were 97% at 1 year, 71% at 3 years, and 48% at 5 years. Median survival was 57 months. The difference between the two survival curves was not statistically significant (P=.5094). Survival of patients treated with RF ablation was dependent on Child class (P=.0006) and tumor multiplicity (P=.0133). Patients who had Child class A cirrhosis with solitary HCC (n=116) had 1-, 3-, and 5-year survival rates of 100%, 89% and 61%; median survival was 65 months. The 1-, 3-, and 5-year recurrence rates were 14%, 49%, and 81% for the emergence of new tumors and 4%, 10%, and 10% for local tumor progression. RF ablation is an effective first-line treatment for cirrhotic patients with early-stage HCC who were excluded from surgery.

Percutaneous image-guided radiofrequency ablation in the therapeutic management of hepatocellular carcinoma

Owing to surveillance programs for detection of hepatocellular carcinoma (HCC) in patients with cirrhosis, more tumors are being detected at an early, asymptomatic stage. Percutaneous ablation is considered the best treatment option for patients with Child-Pugh class A or B cirrhosis and a single, nodular-type HCC smaller than 5 cm or as many as three HCC lesions, each smaller than 3 cm, when surgical resection or liver transplantation is not suitable. Radiofrequency ablation (RFA) has emerged as the most powerful method for percutaneous treatment of early-stage HCC. Recent studies have shown that RFA can achieve more effective local tumor control than ethanol injection and with fewer treatment sessions. In a randomized trial, local recurrence-free survival rates were significantly higher in patients who received RFA than in those treated by ethanol injection, and treatment allocation was confirmed as an independent prognostic factor by multivariate analysis. Due to advances in radiofrequency technology, RFA also has been used to treat patients with more advanced tumors. Preliminary reports have shown that RFA performed after balloon catheter occlusion of the hepatic artery, transarterial embolization, or chemoembolization results in increased volumes of coagulation necrosis, thus enabling successful destruction of large HCC lesions. This report reviews the current status of percutaneous, image-guided RFA in the therapeutic management of HCC.

Imaging-guided radiofrequency ablation of renal masses.

Substantial and growing evidence indicates that imaging-guided percutaneous radiofrequency ablation of small renal cell carcinomas (RCCs) is effective for complete tumor eradication. The rate of successful radiofrequency treatment of small RCCs ranges from 79% to 97%, with a 1% rate of serious complications. For patients who are considered high-risk candidates for nephrectomy, percutaneous radiofrequency ablation represents another treatment option. The article summarizes the published results for this technique and also describes the indications, techniques, procedural risks, and applications for percutaneous radiofrequency ablation of RCCs. The successful use of radiofrequency ablation for treatment of recurrent and metastatic RCCs is also described.

Percutaneous radiofrequency ablation of pulmonary metastases in patients with colorectal cancer.

This study aimed to assess the safety and efficacy of imaging-guided percutaneous radiofrequency ablation (RFA) for local control of lung metastases from colorectal cancer (CRC). Twenty patients with lung metastases from CRC were treated with a RITA Starburst XL electrode and RITA 1500 generator using temperature control and impedance monitoring. Patients received intravenous sedation and analgesia, or local anaesthetic, and stayed in hospital for at least 24 h after treatment. RFA was assessed with computed tomography (CT) at 1 week and 1 month, and then every 3 months. Forty-four CRC lung metastases in 19 patients were treated successfully at 25 treatment sessions. Five of 19 patients were retreated for new lesions. There were 13 pneumothoraces following the 25 treatments, and six patients required drainage. The median length of follow-up was 730 (range 148-924) days. Six months after treatment CT demonstrated that three lesions had progressed, 25 metastases were stable or smaller, and 11 were no longer visible. At 12 months five metastases had progressed, 11 were smaller or stable, and nine were not visible. Percutaneous imaging-guided RFA was associated with modest morbidity. RFA can achieve local control of CRC lung metastases: nine of 25 metastases were not visible on CT at 12 months after treatment.

Remote Thermometry to Avoid Complications in Radiofrequency Ablation

Percutaneous image-guided radiofrequency ablation (RFA) of tumors has the potential risk for thermal damage to nearby normal collateral tissues. Thus, the goal of creating a sufficient area of tumor necrosis must be weighed against the risk for injury to collateral tissues. In this study, remote thermistors were used to monitor temperatures near collateral structures during tumor RFA. Four unique cases are described. When temperature-sensitive structures are near the target lesion, remote thermometry could further increase the safety of this evolving minimally invasive procedure.

Imaging-guided percutaneous radiofrequency ablation of pulmonary metastatic nodules caused by hepatocellular carcinoma: preliminary experience.

The purpose of our study was to evaluate the efficacy of imaging-guided percutaneous radiofrequency ablation of metastatic pulmonary nodules caused by hepatocellular carcinoma. Percutaneous radiofrequency ablation is feasible and can be a promising method for the local control of metastatic pulmonary nodules caused by hepatocellular carcinoma, especially when they are limited in number.

Imaging-guided percutaneous radiofrequency ablation of solid renal masses: techniques and outcomes of 38 treatment sessions in 32 consecutive patients.

The purpose of this study was to describe the treatment techniques and results of 38 consecutive imaging-guided percutaneous radiofrequency ablations of solid renal masses performed in 32 patients. Solid renal masses in 32 patients underwent 38 treatment sessions using imaging-guided percutaneous radiofrequency ablation. During 36 sessions, radiofrequency ablation was performed using CT guidance, and two, using sonographic guidance. The average patient age was 76 years (range, 52-87 years), and the average renal mass size was 2.6 cm (range, 1-5 cm). The average number of radiofrequency treatments per solid mass at each session was 2.4 (range, 1-6 treatments), and the average time per treatment was 9.2 min (range, 3-14 min). A single electrode was used in 12 sessions, and a cluster electrode was used in 26 sessions. The average follow-up time was 9 months (range, 1-36 months). Twenty-six of 32 patients had successful treatment of the solid renal mass using percutaneous imaging-guided radiofrequency ablation after one treatment session. Successful treatment was defined as lack of enhancement of the treated region on follow-up CT. Six of 32 patients had residual enhancing tissue after the first treatment session and returned for a second session. Five of these six retreatments were successful. Masses requiring a second treatment session were significantly larger than masses treated in a single session (3.5 vs 2.4 cm, respectively; p = 0.0013). Two patients had perinephric hematomas (which did not require transfusion), and one patient developed a 5-mm skin metastasis at the electrode insertion site, which was resected without recurrence. Percutaneous imaging-guided radiofrequency ablation shows promise in the treatment of solid renal malignancies.

Early experience with percutaneous radiofrequency ablation of small solid renal masses.

Incidental small renal-cell masses are often seen in elderly patients with significant comorbidity who are unfit to undergo major surgery. This study was conducted to determine the safety and efficacy of percutaneous imaging-guided radiofrequency ablation in the management of small solid renal masses, almost all of which are renal cell cancers. Early experience suggests that radiofrequency ablation is a safe, well-tolerated, and minimally invasive therapy for patients with solid renal masses. In the era of nephron-sparing surgery, radiofrequency ablation may have a role in the management of small problematic renal masses.

Image-guided Percutaneous Radiofrequency Ablation for Osteoid Osteomas

The authors present a retrospective analysis of the technical and clinical successes, complications, and clinical follow-up of image-guided percutaneous radiofrequency (RF) ablation of osteoid osteomas. Nine patients with osteoid osteomas underwent image-guided localization of osteoid osteomas. Outpatient percutaneous therapy (13 procedures) was performed under general anesthesia after image-guided localization of the nidus. Initial technical success was achieved in seven of nine patients. Two initial technical and clinical failures occurred early in this experience because of failure to adequately enter the nidus with use of fluoroscopic imaging alone. Clinical success was achieved in eight of nine patients. No major immediate or delayed complications were observed.

Renal cell carcinoma: clinical experience and technical success with radio-frequency ablation of 42 tumors.

To evaluate clinical experience with percutaneous image-guided radio-frequency (RF) ablation of renal cell carcinoma (RCC) and to assess factors that may influence technical success. Thirty-four patients who underwent RF ablation of 42 RCC tumors during a 3.5-year period were evaluated. Overlapping ablations were performed on the basis of tumor size and geometry. Technical success was defined as elimination of areas that enhanced at imaging within the entire tumor. With the exception of those patients with renal insufficiency, who were followed up with unenhanced and gadolinium-enhanced magnetic resonance imaging, patients were followed up with unenhanced and contrast material-enhanced computed tomography. Univariate analysis of the results was performed with the Fisher exact test to assess the effect of tumor size and location on technical success. P <or=.05 was considered to represent a significant difference. Complications and the management and outcomes of the complications were recorded. All 29 exophytic tumors (mean size, 3.2 cm; size range, 1.1-5.0 cm) were completely ablated, as were two parenchymal tumors. The remaining 11 tumors had a component in the renal sinus. For large (>3.0 cm) tumors, presence of a tumor component in the renal sinus was a significant negative predictor of technical success (P =.004); only five of these 11 tumors were completely treated, compared with 11 of 11 tumors without a renal sinus component. A similar analysis was not possible for small tumors because no small tumors involved the renal sinus. Four complications occurred in a total of 54 ablation sessions: one minor hemorrhage, two major hemorrhages, and one ureteral stricture. RF ablation of RCC can be successful in exophytic RCC tumors up to 5.0 cm in size. Tumors larger than 3.0 cm with a component in the renal sinus are more difficult to treat but can be ablated successfully.

Percutaneous Image-Guided Radiofrequency Ablation of Bone Tumors

Percutaneous Image-Guided Radiofrequency Ablation of Bone Tumors

Painful metastases involving bone: feasibility of percutaneous CT- and US-guided radio-frequency ablation.

To determine the safety and efficacy of radio-frequency (RF) ablation for pain reduction, quality of life improvement, and analgesics use reduction in patients with skeletal metastases. Over 10 months, 12 adult patients with a single painful osteolytic metastasis in whom radiation therapy or chemotherapy had failed and who reported severe pain (pain score > or = 4 [scale of 0-10]) over a 24-hour period were treated with percutaneous imaging-guided RF ablation with a multi-tined electrode while under general anesthesia. Patient pain was measured with a Brief Pain Inventory 1 day after the procedure, every week for 1 month, and thereafter every other week (total follow-up, 6 months). Patient analgesics use was also recorded at these follow-up intervals. Follow-up contrast material-enhanced computed tomography was performed 1 week after the procedure. Complications were monitored. Analysis of the primary end point was undertaken with paired comparison procedures. Lesion size was 1-11 cm. Before RF ablation, mean worst pain score in a 24-hour period in 12 patients was 8.0 (range, 6-10). At 4 weeks after treatment, mean worst pain decreased to 3.1 (P =.001). Mean pain before treatment was 6.5 and decreased to 1.8 (P <.001) 4 weeks after treatment. Mean pain interference in general activity decreased from 6.6 to 2.7 (P =.002) 4 weeks after treatment. Eight of 10 patients using analgesics reported reduced use at some time after RF ablation. No serious complications were observed. RF ablation of painful osteolytic metastases is safe, and the relief of pain is substantial.