Radiofrequency ablation alone or in combination with cementoplasty for local control and pain palliation of sacral metastases: preliminary results in 11 patients

Microwave ablation combined with percutaneous vertebroplasty for treating painful non-small cell lung cancer with spinal metastases under real-time temperature monitoring

PURPOSE

To retrospectively study the therapeutic effect and safety performance of the combination strategies of the computed tomography (CT)-guided microwave ablation (MWA) and percutaneous vertebroplasty (PVP) as a treatment for painful non-small cell lung cancer (NSCLC) with spinal metastases.

MATERIALS AND METHODS

A retrospective review included 71 patients with 109 vertebral metastases who underwent microwave ablation combined with percutaneous vertebroplasty by the image-guided and real-time temperature monitoring. Treatment efficacy was determined by comparing visual analog scale (VAS) scores, daily morphine equivalent opioid consumption, and Oswestry Disability Index (ODI) scores before treatment and during the follow-up period.

RESULTS

Technical success was achieved in all patients. The mean pre-procedure VAS score and morphine doses were 6.6 ± 1.8 (4-10) and 137.2 ± 38.7 (40-200) mg, respectively. The mean VAS scores and daily morphine doses at 24 h and 1, 4, 12, and 24 weeks postoperatively were 3.3 ± 1.9 and 73.5 ± 39.4 mg; 2.2 ± 1.5 and 40.2 ± 29.8 mg; 1.7 ± 1.2 and 31.3 ± 23.6 mg; 1.4 ± 1.1 and 27.3 ± 21.4 mg; and 1.3 ± 1.1 and 24.8 ± 21.0 mg, respectively (all P < 0.001). ODI scores significantly decreased (P < 0.05). Minor cement leakage occurred in 51 cases (46.8%), with one patient having a grade 3 neural injury. No local tumor progression was observed by follow-up imaging.

CONCLUSIONS

MWA combined with PVP can significantly relieve pain and improve patients' quality of life, which implied this is an effective treatment option for painful NSCLC with spinal metastases. Additionally, its efficacy should be further verified through the mid- and long-term studies.

Percutaneous Sacroplasty with or without Radiofrequency Ablation for Treatment of Painful Sacral Metastases

BACKGROUND AND PURPOSE

Percutaneous sacroplasty is a variation of percutaneous vertebroplasty that has gained attention as a therapeutic option for patients with painful sacral insufficiency fractures due to osteoporosis or metastases. Additionally, percutaneous sacroplasty can also be used to treat painful sacral metastases without a pathologic fracture. The purpose of this retrospective study was to compare the efficacy and safety of fluoroscopy-guided percutaneous sacroplasty alone versus percutaneous sacroplasty plus radiofrequency ablation for the treatment of painful sacral metastases.

MATERIALS AND METHODS

For this retrospective study, 126 patients (with a total of 162 painful sacral metastases) were enrolled from October 2012 to February 2021 and assigned to receive either percutaneous sacroplasty plus radiofrequency ablation (n = 51, group A) or percutaneous sacroplasty alone (n = 75, group B). Four different approaches were used for percutaneous sacroplasty: transiliac, interpedicular, anterior-oblique, and posterior. The Visual Analog Scale, Oswestry Disability Index, and Karnofsky Performance Scale were used to evaluate outcomes.

RESULTS

The Visual Analog Scale, Oswestry Disability Index, and Karnofsky Performance Scale scores showed significant improvement in both groups after treatment (P < .05). The overall pain relief rate was significantly better in group A than in group B (90% versus 76%, P = .032). There were no significant differences in the incidence of polymethylmethacrylate leakage between the 2 groups or among the 4 different approaches (P > .05).

CONCLUSIONS

Both percutaneous sacroplasty alone and the combination of percutaneous sacroplasty and radiofrequency ablation are safe and effective for treatment of painful sacral metastases. The combination of percutaneous sacroplasty and radiofrequency ablation appears to be more effective than percutaneous sacroplasty alone.

Interventional Radiology in the Management of Metastases and Bone Tumors

Interventional Radiology (IR) has experienced an exponential growth in recent years. Technological advances of the last decades have made it possible to use new treatments on a larger scale, with good results in terms of safety and effectiveness. In musculoskeletal field, painful bone metastases are the most common target of IR palliative treatments; however, in selected cases of bone metastases, IR may play a curative role, also in combination with other techniques (surgery, radiation and oncology therapies, etc.). Primary malignant bone tumors are extremely rare compared with secondary bone lesions: osteosarcoma, Ewing sarcoma, and chondrosarcoma are the most common; however, the role of interventional radiology in this fiels is marginal. In this review, the main techniques used in interventional radiology were examined, and advantages and limitations illustrated. Techniques of ablation (Radiofrequency, Microwaves, Cryoablation as also magnetic resonance imaging-guided high-intensity focused ultrasound), embolization, and Cementoplasty will be described. The techniques of ablation work by destruction of pathological tissue by thermal energy (by an increase of temperature up to 90 °C with the exception of the Cryoablation that works by freezing the tissue up to -40 °C). Embolization creates an ischemic necrosis by the occlusion of the arterial vessels that feed the tumor. Finally, cementoplasty has the aim of strengthening bone segment weakened by the growth of pathological tissue through the injection of cement. The results of the treatments performed so far were also assessed and presented focused the attention on the management of bone metastasis.

The Addition of Radiofrequency Tumor Ablation to Kyphoplasty May Reduce the Rate of Local Recurrence in Spinal Metastases Secondary to Breast Cancer

BACKGROUND

Approximately 10% of all cancer patients develop spinal metastases. When a symptomatic compression fracture occurs without associated deformity or neurologic deficit, it can be treated with kyphoplasty with or without radiofrequency ablation (RFA). Treatment with kyphoplasty is well established but does not address the underlying oncologic disease.

METHODS

Retrospective medical chart analysis of breast cancer patients (n = 23) with metastatic spinal fractures (n = 50 vertebral levels) who underwent RFA and kyphoplasty was undertaken. Key variables of interest included: fracture location, pain levels, and local recurrence. Local recurrence data were compared to published rates of recurrence in breast cancer-related metastatic spinal fractures treated with vertebroplasty or kyphoplasty alone. Data were analyzed using χ² and t test statistical analyses.

RESULTS

The mean preoperative pain level for this cohort was 6.9 on a 10-point visual analogue scale. Significant reductions in pain levels were observed postoperatively, at discharge (3.5; P < 0.05), at 1-month follow-up (2.8; P < 0.05), at 3-month follow-up (1.1; P < 0.05), and at 6-month follow-up (0.7 P < 0.05). Compared with published data of breast cancer patients with metastatic spinal fractures treated with vertebroplasty or kyphoplasty alone, the addition of RFA resulted in reduced local tumor recurrence (2% vs. 14%; P < 0.05). Average length of follow-up was 39 months.

CONCLUSIONS

The results suggest that the addition of RFA to kyphoplasty may reduce local tumor recurrence while providing similar pain relief benefits. The extrapolation of this added benefit to metastases from other primary cancers should be examined in future studies.

Management of Spinal Bone Metastases With Radiofrequency Ablation, Vertebral Reinforcement and Transpedicular Fixation: A Retrospective Single-Center Case Series

Spine is a frequent site of bone metastases, with a 8.5 months median survival time after diagnosis. In most cases treatment is only palliative. Several advanced techniques can ensure a better Quality of Life (QoL) and increase life expectancy. Radiofrequency ablation (RFA) uses alternating current to produce local heating and necrosis of the spinal lesion, preserving the healthy bone. RFA is supported by vertebral reinforcement through kyphoplasty and vertebroplasty in order to stabilize the fracture with polymethylmethacrylate (PMMA) injection, restoring vertebral body height and reducing the weakness of healthy bone. The aim of this study is to demonstrate the efficacy and advantages of RFA plus vertebral reinforcement through PMMA vertebroplasty and fixation in patients affected by bone spinal metastases. We retrospectively analyzed 54 patients with thoraco-lumbar metastatic vertebral fractures admitted to our Unit between January 2014 and June 2020. Each patient underwent RFA followed by PMMA vertebroplasty and transpedicle fixation. We evaluated pain relief through the Visual Analogue Scale (VAS) Score and PMMA vertebral filling based on the mean Saliou filling score. Analysis of variance (ANOVA) was used to test pain relief with statistical significance for p<0.05. A total of 54 patients (median age 63,44 years; range 34-86 years), with a total of 63 infiltrated vertebrae, were treated with RFA, PMMA vertebroplasty and transpedicular screw fixation; average operative time was 60.4 min (range 51–72). The preoperative average VAS score decreased significantly from 7.81 to 2.50 (p < 0.05) after 12 months. Based on Saliou filling score, filling was satisfactory (12–18) in 20 vertebrae (31,7%), mediocre (6–11) in 33 vertebrae (52,4%), inadequate (0–5) in 10 vertebrae (15,9%). A consistent PMMA filling of vertebral bodies was successfully achieved with significant pain relief. Concomitant RFA, PMMA vertebroplasty and pedicle screw fixation represent a safe and effective technique for the management of spinal metastases, improving clinical outcome and pain control.

Ablation Techniques in Cancer Pain

Painful bone metastases are a frequently encountered problem in oncology practice. The skeletal system is the third most common site of metastatic disease and up to 85% of patients with breast, prostate, and lung cancer may develop bone metastases during the course of their disease.

Computed tomography-guided microwave ablation combined with percutaneous vertebroplasty for treatment of painful high thoracic vertebral metastases

PURPOSE

To retrospectively evaluate the efficacy and safety of computed tomography (CT)-guided microwave ablation (MWA) combined with percutaneous vertebroplasty (PVP) as a treatment for painful high thoracic vertebral metastases (T1-T4).

MATERIALS AND METHODS

In this retrospective study, 23 adult patients (33 high thoracic vertebral metastases) with moderate to severe pain were treated with CT-guided MWA and PVP. The procedural effectiveness was evaluated using a Visual Analog Scale (VAS), daily morphine consumption, and the Oswestry Disability Index (ODI) before and immediately after the procedure and during follow-up.

RESULTS

Technical success was achieved in all patients. The mean pre-procedure VAS score and morphine doses were 6.7 ± 1.7 (5-10) and 105.2 ± 32.7 (30-150) mg, respectively. The mean VAS scores and daily morphine doses at 24 h and 1, 4, 12, and 24 weeks post-operatively were 3.2 ± 1.4 and 41.3 ± 9.6 mg; 1.8 ± 1.0 and 31.5 ± 12.2 mg; 1.4 ± 1.3 and 19.6 ± 12.4 mg; 1.1 ± 0.8 and 14.5 ± 9.6 mg; and 1.0 ± 0.7 and 13.9 ± 9.3 mg, respectively (all p < 0.001). ODI scores significantly decreased (p < 0.05). Minor cement leakage occurred in 10 patients (30.30%) with no symptoms. Follow-up imaging showed no local tumor progression.

CONCLUSIONS

Preliminary results suggest MWA combined with PVP is an effective and safe treatment for painful high thoracic vertebral metastases (T1-T4) and can significantly relieve pain and improve the quality of life of patients. However, its efficacy should be confirmed by mid- and long-term studies.

Surgical Treatment of Sacral Metastatic Tumors

Objective

This study intends to retrospectively analyze the data of patients with sacral metastases in our center, and analyze the treatment methods and therapeutic effects of sacral metastases.

Methods

73 patients with sacral metastases treated in our hospital from June 2013 to June 2019 were retrospectively analyzed. There were 54 cases of neurological symptoms, 42 cases of sacroiliac joint instability, 24 cases of lower limb muscle weakness and 19 cases of abnormal urination and defecation. Four patients with tumors below S3 underwent complete tumor resection, 23 patients with tumors above S3 and without sacroiliac joint instability underwent tumor curettage and nerve root lysis, 34 patients with tumors above S3 and sacroiliac joint instability underwent tumor curettage, nerve root release and screw rod reconstruction. 12 patients with multiple metastases underwent percutaneous radiofrequency ablation and sacroplasty. VAS was used to evaluate the preoperative and postoperative pain scores, and the postoperative pain relief, neurological function, bowel function, wound healing and complications were evaluated.

Results

There were no perioperative death, 8 cases of poor wound healing, 5 cases of nerve injury, postoperative sensory and motor loss of lower limbs. Cerebrospinal fluid (CSF) leak in 7 cases. The patients were followed up for 6-25 months (mean 12 months). The VAS scores of patients with pain symptoms were 7 points before operation and 1.44 points after operation, In 19 patients with abnormal urination and defecation function, 12 patients recovered to normal 3-6 months after operation, 5 cases had no significant change compared with preoperative, and 2 cases had aggravated symptoms; 17 cases of patients with lower limb muscle strength were significantly recovered after operation, and the average muscle strength was increased by 2 grades; 30 cases of patients with unstable sacroiliac joint got internal fixation had significantly pain relief. Pain symptoms of 9 patients were significantly relieved after percutaneous radiofrequency ablation.

Conclusion

the operation of sacral metastases mainly adopts a relatively conservative surgical method, which can effectively improve the quality of life of patients with sacral metastases by retaining the nerve function and relieving the pain of patients, combining with radiofrequency ablation, sacroplasty and targeted drugs.

Percutaneous thermal ablation of sacral metastases: Assessment of pain relief and local tumor control

PURPOSE

To retrospectively report on safety, pain relief and local tumor control achieved with percutaneous ablation of sacral bone metastases.

MATERIALS AND METHODS

From February 2009 to June 2020, 23 consecutive patients (12 women and 11 men; mean age, 60±8 [SD] years; median, 60; range: 48-80 years) with 23 sacral metastases underwent radiofrequency (RFA) or cryo-ablation (CA), with palliative or curative intent at our institution. Patients' demographics and data pertaining to treated metastases, procedure-related variables, safety, and clinical evolution following ablation were collected and analyzed. Pain was assessed with numerical pain rating scale (NPRS).

RESULTS

Sixteen (70%) patients were treated with palliative and 7 (30%) with curative intent. Mean tumor diameter was 38±19 (SD) mm (median, 36; range: 11-76). External radiation therapy had been performed on five metastases (5/23; 22%) prior to ablation. RFA was used in 9 (39%) metastases and CA in the remaining 14 (61%). Thermo-protective measures and adjuvant bone consolidation were used whilst treating 20 (87%) and 8 (35%) metastases, respectively. Five (22%) minor complications were recorded. At mean 31±21 (SD) (median, 32; range: 2-70) months follow-up mean NPRS was 2±2 (SD) (median, 1; range: 0-6) vs. 5±1 (median, 5; range: 4-8; P<0.001) at the baseline. Three metastases out of 7 (43%) undergoing curative ablation showed local progression at mean 4±4 (SD) (median, 2; range: 1-8) months follow-up.

CONCLUSION

Percutaneous ablation of sacral metastases is safe and results in significant long-lasting pain relief. Local tumor control seems sub-optimal; however, further investigations are needed to confirm these findings due to paucity of data.

Percutaneous thermal ablation alone or in combination with cementoplasty for renal cell carcinoma osseous metastases: Pain palliation and local tumour control

INTRODUCTION

To evaluate the safety and efficacy of minimally invasive percutaneous thermal ablation alone or in combination with cementoplasty for pain palliation and local tumour control of renal cell carcinoma osseous metastases.

METHODS

Imaging-guided thermal ablation was performed in 59 renal cell carcinoma osseous metastatic tumours in 23 patients (concomitant cementoplasty in 43 tumours) selected following multidisciplinary consultations to achieve local tumour control and pain palliation (75%, 44/59) or pain palliation alone (25%, 15/59) in this retrospective study. Tumour characteristics, procedural details and complications were documented. Pain palliation was assessed using pre- and post-procedural Numeric Rating Scale scores at 1-week, 1-month, 3-month and 6-month time intervals. Pre- and post-procedural cross-sectional imaging was reviewed to assess local tumour control rates at 3-month, 6-month, and 12-month post-treatment time intervals.

RESULTS

All procedures were technically successful and performed as pre-operatively planned. The median pre- and post-procedural Numeric Rating Scale scores were 8.0 and 3.0 (at all time intervals), respectively (P < 0.001). Local tumour control rates were 100% (40/40), 100% (36/36) and 85% (28/33) at ≥3 months, ≥6 months and ≥12 months post-procedural time intervals, respectively. There was 1 minor complication (1.7%, 1/59).

CONCLUSIONS

Percutaneous thermal ablation alone or in combination with cementoplasty is safe and effective for pain palliation and local tumour control of renal cell carcinoma osseous metastases.

Analgesia of percutaneous thermal ablation plus cementoplasty for cancer bone metastases

Background

The purpose of this study was to review recent research related to the analgesic effect of ablation therapy combined with cementoplasty, as well as to identify the duration of analgesic effect and risk for cement leaks.

Methods

A systematic literature search using PubMed, Web of Science, and annual meeting proceedings of the oncology society and other organizations were conducted.

Results

Twelve retrospective studies met the inclusion criteria. Four of the studies included in the review assessed the changes immediately after treatment. Five studies were subjected to analyses of analgesic effect of combined percutaneous thermal ablation and Cementoplasty at 24 weeks after treatment. Incidences of leakage of bone cement during surgery were detected in 4 out of 12 studies. The change of mean pain scores at 1 days, at 1 week, and at 4 weeks, 12 weeks, and 24 weeks after treatment were -3.90 (95% CI: -4.80 to -3.00), -4.55 (95% CI:-5.46 to -3.64), -4.78 (95% CI: -5.70 to -3.86), -5.16 (95% CI: -6.39 to -3.92), and -5.91 (95% CI: -6.63 to -5.19). The relative risk of cement leakage was 0.10 (95% CI: -6.63 to -5.19).

Conclusions

Our systematic review suggested that thermal ablation combined with cementoplasty could be a safe and effective intervention for the management of bone metastases-induced pain.

Sacral Fractures and Sacroplasty

Sacral fractures result from high-impact trauma or in the form of insufficiency or pathologic fractures, resulting from osteoporosis, radiation therapy, or malignancy. In the emergency setting, the escalating use of computed tomography has substantially increased diagnosis of sacral fractures, which are frequently occult on radiographs. Radiologists should be familiar with and create reports using the most current fracture classification systems, because this improves communication with the treatment team and optimizes patient care. Sacroplasty is a safe, minimally invasive treatment option for many types of sacral fractures. It provides rapid and durable pain relief, with a low incidence of complications.

Minimally Invasive Stabilization Using Screws and Cement for Pelvic Metastases: Technical Considerations for the Pelvic "Screw and Glue" Technique

Metastatic disease involving the pelvis is common, often resulting in significant pain and disability. Several percutaneous interventions for unstable pelvic metastatic disease have been described, including osteoplasty, ablation, and screw fixation, that when used alone or in combination can significantly reduce pain and disability from metastatic bone disease. While it is possible to make a significant impact in patient care with basic principles and techniques, certain advanced techniques can extend the application of percutaneous interventions while minimizing morbidity.

Multidisciplinary Management of Spinal Metastasis and Vertebral Instability: A Systematic Review

OBJECTIVE

The aim of this systematic literature review is to evaluate recent attempts in creating a standardized multidisciplinary approach combining tumor treatment with current vertebral stabilization techniques for palliative treatment of vertebral metastasis in patients who do not fall into the NOMS (neurologic, oncologic, mechanical, systemic) framework.

METHODS

We performed a systematic literature search for studies using a tumor modality in conjunction with kyphoplasty or vertebroplasty. In addition, the bibliographies of selected articles were examined for additional studies not viewed in database searches, which led to the use of additional search terms.

RESULTS

A total of 563 articles were found after our database search. Eighteen studies fulfilled our inclusion criteria. Articles were then divided into categories based on combinations of tumor modality. Multiple studies reported significant decreases in visual analog scale scores after combined procedures with very low rates of symptomatic complications. Studies that compared their combination with control treatment groups showed greater clinical efficacy.

CONCLUSIONS

Although multidisciplinary management of spinal metastasis using a combination of tumor ablation techniques with vertebral stabilization has been recommended in the previous literature, this review shows that no combination of treatment carried demonstrably different results in pain score reduction, reduced analgesic intake, or improved quality of life. In addition, there is no consensus of standardized variables to evaluate efficacy of treatment, limiting the efficacy of treatment results for the analyzed studies. Although not explicitly included in the initial NOMS framework, our results support the consideration of concomitant percutaneous kyphoplasty or vertebroplasty in these patients on a case-by-case basis.

CT fluoroscopy-guided percutaneous osteoplasty with or without radiofrequency ablation in the treatment of painful extraspinal and spinal bone metastases: technical outcome and complications in 29 patients

PURPOSE

We aimed to assess the safety and technical outcome of computed tomography (CT) fluoroscopy-guided osteoplasty with or without prior percutaneous radiofrequency ablation (RFA) in patients with painful osteolyses.

METHODS

We performed a retrospective analysis of 29 patients with painful extraspinal and spinal osteolyses (16 women, 13 men; 63.1±14.4 years) who underwent CT fluoroscopy-guided osteoplasty (10-20 mAs tube current) with or without RFA (26 and 14 lesions, respectively), in 33 consecutive procedures from 2002 to 2016. Technical success was defined as at least one complete RFA cycle and subsequent polymethyl metacrylate (PMMA) bone cement injection covering ≥75% of longest diameter of extraspinal osteolysis on axial plane or of distance between vertebral endplates. Procedure-related complications within 30 days and dose-length-product (DLP) were also evaluated.

RESULTS

Osteolyses were located in the pelvis (acetabulum, n=10; iliac bone, n=4), spine (thoracic, n=6; lumbar, n=5; sacral, n=8), long bones (femur, n=3; tibia, n=1), sternum (n=2) and glenoid (n=1). Mean size of the treated osteolysis was 4.0±1.2 cm (range, 1.9-6.9 cm). Of 40 osteolyses, 31 (77.5%) abutted neighboring risk structures (spinal canal or neuroforamen, n=18; neighboring joint, n=11; other, n=8). Mean number of RFA electrode positions and complete ablation cycles was 1.5±0.9 and 2.1±1.7, respectively. Mean PMMA filling volume was 7.7±5.7 mL (range, 2-30 mL). Small asymptomatic PMMA leakages were observed in 15 lesions (37.5%). Mean total DLP was 850±653 mGy*cm. Six minor complications were observed, without any major complications.

CONCLUSION

CT fluoroscopy-guided percutaneous osteoplasty with or without concomitant RFA for the treatment of painful extraspinal and spinal osteolyses can be performed with a low complication rate and high technical success.

Thermal effect of percutaneous radiofrequency ablation with a clustered electrode for vertebral tumors: In vitro and vivo experiments and clinical application

Purpose

To investigate effects and heat distribution of radiofrequency ablation (RFA) on vertebral tumors in vitro and in vivo swine experiments and its clinical application.

Materials and methods

RFA was performed on the swine spine in vitro and in vivo for 20 min at 90 °C at the electrode tip, and the temperature at the electrode tip and surrounding tissues were recorded. Clinical application of ablation combined with vertebroplasty was subsequently performed in 4 patients with spinal tumors.

Results

In the in vitro study, the mean temperature at the front and ventral wall of the spinal canal was 50.8 °C and 43.6 °C, respectively, at 20 mm significantly greater than 37.7 °C and 33.7 ± 1.7 °C, respectively, at 10 mm ablation depth. The coagulative necrosis area was significantly (P < 0.0001) greater at 20 mm depth than at 10 mm depth (mean 17.0 × 20.7 mm² vs. 14.2 × 16.6 mm²). In the in vivo experiment, the local temperature increased significantly (P < 0.05) from around 36 °C before ablation to over 41 °C at 20 min after ablation, with the temperature at the electrode tip (90.4 °C) and within the vertebral body (67.0 °C) significantly (P < 0.05) greater than at the posterior (41.9 °C) and lateral wall (41.8 °C). From 2 to 5 weeks, bone remodeling began. Clinically, all four patients had successful RFA and vertebroplasty, with no neurological deficits. The pain scores were significanlty (P < 0.05) improved before (4.5–10, mean 8.0) compared with at four weeks (0–1.8, mean 1.8).

Conclusion

The clustered electrode can be efficiently and safely applied in the treatment of spinal tumors without damaging the spinal cord and adjacent nerves by heat distribution.

Percutaneous Radiofrequency Ablation for Painful Spinal Metastases Resulting in Resolution of Epidural Disease: A Case Report

Percutaneous image-guided ablation is used for treatment of both benign and malignant osseous lesions often leading to substantial pain relief and local tumor control. Paired with vertebral augmentation of the affected vertebra, patients can often become functional and experience significant pain reduction. However, bone ablation must be paired with various modalities of treatment as it only provides pain relief and local tumor control and does not address systemic metastatic disease.

We describe a case of metastatic prostate cancer with epidural extension treated with percutaneous image-guided radiofrequency ablation and vertebral augmentation leading to substantial pain relief as well as resolution of the epidural disease as evidenced by short-term follow-up magnetic resonance imaging (MRI). To the best of our knowledge, the resolution of epidural disease has not been described before. This case highlights the potential of ablative therapy in metastatic bone disease, particularly in the presence of epidural disease.

Decision Making: Osteoplasty, Ablation, or Combined Therapy for Spinal Metastases

Metastatic disease involving the spine and pelvis is common, often resulting in significant pain and disability. Several percutaneous interventions have been described, including osteoplasty, ablation, and screw fixation, that when used alone or in combination can significantly reduce pain and disability from metastatic bone disease. Although it is possible to make a significant impact in patient care with basic principles and techniques, certain advanced techniques can extend the application of percutaneous interventions while minimizing morbidity.

Treatment of osseous metastases using the Spinal Tumor Ablation with Radiofrequency (STAR) system

INTRODUCTION

Percutaneous ablation is an emerging, minimally invasive therapy for patients with osseous metastases who have not responded or have contraindications to radiation therapy. Goals of therapy are pain relief, and in some cases, prevention of local tumor progression. Areas covered: The epidemiology, pathophysiology, natural history, and traditional management of metastatic bone disease are reviewed. Novel features of the Spinal Tumor Ablation with Radiofrequency (STAR) System (DFINE, San Jose, CA) that facilitate treatment of osseous metastases are described, including the bipolar electrode, extensible distal tip that can be curved up to 90°, and inclusion of thermocouples that enable real-time monitoring of the ablation zone volume. Lastly, research evaluating the safety and efficacy of using this device to treat musculoskeletal metastases is summarized. Expert commentary: Although evidence supporting the efficacy of RFA for the treatment of bone metastases is limited to case series, it is a reasonable therapy when other options have been exhausted, especially given the safety and minimal morbidity of the procedure. The STAR Tumor Ablation System has expanded the anatomic scope of bone metastases that can be safely and effectively treated with percutaneous ablation.