Clinical Literature

Published Results

Published clinical data show that rapid and meaningful pain relief from metastatic spinal tumors is a reality for patients who receive t-RFA using the STAR System. 

Peer-reviewed journal articles include the following:
Treatment of Metastatic Spinal Lesions with a Navigational Bipolar Radiofrequency Ablation Device: A Multicenter Retrospective Study
Praveen R. Anchala, MD, Winston D. Irving, MD, Travis J. Hillen, MD, Michael V. Friedman, MD, Bassem A. Georgy, MD, Douglass, M. Coldwell, MD, PhD, Nam D. Tran, MD, PhD, Frank D. Vrionis MD, PhD, Allan Brook, MD, and Jack W. Jennings, MD, PhD

Article presented the reality of Fast and Lasting Relief from Painful Metastatic Lesions.

Pain Physician 2014; 17:317-327 • ISSN 1533-3159
Pubmed PMID: 25054391

Treatment of Metastatic Posterior Vertebral Body Osseous Tumors by Using a Targeted Bipolar Radiofrequency Ablation Device: Technical Note
Travis J. Hillen, MD, Praveen R. Anchala, MD, Michael V. Friedman, and Jack W. Jennings, MD, PhD

This article presented how Targeted Radiofrequency Ablation (t-RFA) with the STAR Tumor Ablation System can serve as a Minimally Invasive Solution to Safely and Effectively Treat Previously Inaccessible Spinal Lesions.
Hillen, et al., Radiology. 2014 Oct;273(1):261-7.
Pubmed PMID: 24927327

Presented abstracts include the following:
Management of cancer treatment-related painful bone lesions
Mounika Mandadi, Melissa Potts, Martin Sven Vyleta, Mahmoud Samman, Goetz H. Kloecker, Douglas M. Coldwell.
James Graham Brown Cancer Center, Louisville, KY
Background: The use of chemotherapy agents and general inactivity in cancer patients increases osteopenia with the resulting vertebral compression fractures and other bony lesions. Frequently these lesions are the site of pain that results in the decrease in mobility and quality of life. Local measures to treat these lesions have traditionally relied only on radiotherapy but the use of vertebral augmentation is an attractive alternate for those patients who are either refractory to radiotherapeutic options or have marrow eliminating response to chemotherapy for multiple myeloma.

Methods: A retrospective review of 37 patients (19 men, 18 women, mean age 64 years) who received vertebral augmentation was performed. There were two patients who had sterna fractures due to marrow elimination due to successful myeloma treatment, 8 sacral fractures and radio-resistant tumors, and the remainder of the patients had vertebral compression fractures at 46 levels in 27 patients. All patients received vertebral augmentation with polymethylmethacrylate cement after use of radiofrequency ablation of the tumor with a purpose designed bipolar needle (DFINE, Inc., San Jose, CA) had been performed.

Results: Prior to treatment the pain score (1-10) was a mean of 8.2 and 2 hours following treatment was 1.1 (p<0.05) and one week later was 1.0 (p<0.05). Complications included one case of foot drop that did not resolve after six months in a case of sacral augmentation.

Conclusions: Vertebral augmentation with radiofrequency ablation is an effective method to control bone pain due to localized lesions in cancer patients.

J Clin Oncol 32, 2014 (suppl; abstr e20543)

Targeted Radiofrequency Ablation (T-RFA) with Vertebral Augmentation for the Treatment of Symptomatic Metastatic Spinal Tumors: Safety and Efficacy of a Novel Single Treatment System

S. Dhand, J.A. Tepper, S.J. Smith, R.K. Ryu; Northwestern University, Chicago, IL, United States.

•    10 patients & 12 lesions treated
•    All patients failed conventional chemotherapy and radiation therapy
•    All patients reported significant pain relief
•    No complications


Treatment of spinal tumors is commonly a multidisciplinary approach, often with several separate therapies to treat the patient’s pain.  We aim to evaluate the safety and efficacy of targeted radiofrequency ablation (t-RFA) combined with vertebral augmentation in patients with symptomatic spinal tumors.


Patients with symptomatic vertebral body metastatic tumors who failed conventional chemotherapy and radiation therapy were prospectively enrolled in this study.  All patients underwent fluoroscopically guided vertebral tumor ablation using a single coaxial system (DFINE, San Jose, CA) to deliver a cooled curved ablation probe into the tumor substance, which was heated by RF energy with overlapping ablation zones.  Injection of ultra-high viscosity bone cement was then performed into the ablated tumor bed.  Pain relief was evaluated with the use of the visual analogue scale (VAS score), obtained before and after the procedure.  T-test was used for statistical analysis with the null hypothesis rejected at p<0.05.


A total of 12 lesions were treated in ten patients.  The procedures were all technically successful in all levels treated (12/12, 100%).  All patients reported a significant decrease in pain shortly after treatment: the mean VAS score before treatment was 8.8 (range (5-10) compared to 2.6 (range 0-6) at a mean of 3.8 days after treatment (range 0-10 days, P<0.01).  No treatment-related complications occurred during the follow up period.
Combined targeted RFA and vertebral augmentation using a single delivery system was safe and effective for the management of painful vertebral tumors. The procedure significantly reduced associated pain that was otherwise not responsive to traditional treatment methods. (emphasis added)

Dhand, et al., JVIR 2013.24(7): p. 1077-78.

Targeted radiofrequency ablation (t-RFA) of metastatic posterior vertebral body lesions in patients with soft tissue sarcomas
J. Ley, J. Jennings, J. Baker, T. Hillen, B. Van Tine; Washington University School of Medicine in St. Louis, St. Louis, MO, United States


•    Five patients with metastatic sarcoma with continued progression of lesion following radiation therapy
•    Post ablation lesion necrosis with no interruption of primary systemic therapy
•    All patients reported pain relief
•    No evidence of malignancy or tumor re-growth through 10 months post procedure


Metastatic spinal lesions can be debilitating with significant impact on patients quality of life. Concern for damage to adjacent neural elements during treatment exist due to high radiation doses required to treat certain radioresistant spinal lesions such as soft tissue sarcoma. Radiofrequency ablation (RFA) of metastatic lesions has been shown to be effective in bone. Spine anatomy presents challenges for minimally invasive (MI) treatment of posterior vertebral body lesions. Targeted RFA (t-RFA) using a novel tumor ablation system, designed for spinal anatomy is evaluated in patients with symptomatic posterior vertebral wall spinal lesions.


Five patients with metastatic leiomyosarcoma or liposarcoma and posterior vertebral body spine lesions, treated by prior radiation with continued progression of lesion size and pain received t-RFA, using a novel spinal tumor ablation system (STAR, DFINE), which contains an articulating bipolar, extensible electrode for navigation. Device thermocouples (TC) permit real time monitoring of the ablation zones to determine size. Sequential post-procedural pain scores, PET and contrast enhanced magnetic resonance imaging, and histopathology of treated area was performed.


No complications or thermal injury occurred. Intra-procedural imaging demonstrated the articulated, bipolar instrument was able to navigate to posterior lesions. Post-ablation MRI demonstrated lesion necrosis within a discrete ablation zone. No evidence of malignancy by PET or histopathology was noted through 10 months. All patients reported post procedural pain relief. Systemic therapy was not interrupted. (emphasis added)


Navigational t-RFA proved a safe and effective, non-ionizing palliative therapy alternative for radio-resistant lesions. Post-ablation imaging and histology confirmed metastatic lesions were necrotic and included in ablation zone with tumor control 10 mos post treatment. Ablation zone was very consistent with real time temperature readings. t-RFA permitted MI targeted treatment of lesions within close proximity of spinal cord, not controlled by systemic therapy. Prospective clinical trial is under preparation
J Clin Oncol 31, 2013 (suppll abstr 10585)