Image-guided percutaneous ablation of bone and soft tissue tumors

Magnetic resonance-guided focused ultrasound versus percutaneous thermal ablation in local control of bone oligometastases: a systematic review and meta-analysis

BACKGROUND

The percutaneous thermal ablation techniques (pTA) are radiofrequency ablation, cryoablation, and microwave ablation, suitable for the treatment of bone oligometastases. Magnetic resonance-guided focused ultrasound (MRgFUS) is a noninvasive ablation technique.

OBJECTIVES

To compare the effectiveness and safety of MRgFUS and pTA for treating bone oligometastases and their complications.

METHODS

Studies were selected with a PICO/PRISMA protocol: pTA or MRgFUS in patients with bone oligometastases; non-exclusive curative treatment. Exclusion criteria were: primary bone tumor; concurrent radiation therapy; palliative therapy; and absence of imaging at follow-up. PubMed, BioMed Central, and Scopus were searched. The modified Newcastle-Ottawa Scale assessed articles quality. For each treatment (pTA and MRgFUS), we conducted two separate random-effects meta-analyses to estimate the pooled effectiveness and safety. The effectiveness was assessed by combining the proportions of treated lesions achieving local tumor control (LTC); the safety by combining the complications rates of treated patients. Meta-regression analyses were performed to identify any outcome predictor.

RESULTS

A total of 24 articles were included. Pooled LTC rate for MRgFUS was 84% (N = 7, 95% CI 66-97%, I2 = 74.7%) compared to 65% of pTA (N = 17, 95% CI 51-78%, I2 = 89.3%). Pooled complications rate was similar, respectively, 13% (95% CI 1-32%, I2 = 81.0%) for MRgFUS and 12% (95% CI 8-18%, I2 = 39.9%) for pTA, but major complications were recorded with pTA only. The meta-regression analyses, including technique type, study design, tumor, and follow-up, found no significant predictors.

DISCUSSION

The effectiveness and safety of the two techniques were found comparable, even though MRgFUS is a noninvasive treatment that did not cause any major complication. Limited data availability on MRgFUS and the lack of direct comparisons with pTA may affect these findings.

CONCLUSIONS

MRgFUS can be a valid, safe, and noninvasive treatment for bone oligometastases. Direct comparison studies are needed to confirm its promising benefits.

Resolution of Pain after Percutaneous Image-Guided Cryoablation of Extraperitoneal Endometriosis

PURPOSE

To retrospectively evaluate the relief of pain after percutaneous image-guided cryoablation of symptomatic extraperitoneal endometriosis (EE).

MATERIAL AND METHODS

From 2017 to 2022, cryoablation of EE was performed at a single institution on a total of 47 lesions in 42 consecutive patients (median age, 37 years; interquartile range [IQR], 33-39.5 years). Patient and procedural characteristics were reviewed retrospectively. Tolerance and outcomes in terms of pain and patient satisfaction were evaluated.

RESULTS

The median follow-up duration was 13.5 months (IQR, 1.1-37.7 months) after cryoablation. The median pain-free survival rate was 93.8% (95% confidence interval [CI], 77.3-98.4) at 6 months and 82.7% (95% CI, 58.8-93.5) after 12 months. Pain decreased from a median of 8/10 (IQR, 7-9) on the visual analog scale to 0/10 (IQR, 0-1) at the last follow-up (P < .0001). The median Patient Global Impression of Change score recorded at the last follow-up was 1/7 (IQR, 1-2). The efficacy rate of cryoablation to avoid secondary surgery was 92.8% (39/42) per patient and 93.6% (44/47) per nodule treated. Four patients (9.5%, 4/42) experienced an adverse event in the days following the procedure, and 1 patient (2%) experienced a severe adverse event.

CONCLUSIONS

Percutaneous cryoablation is safe and effective in significantly reducing pain and obtaining local control of EE.

Transarterial Embolization and Percutaneous Ablation of Primary and Metastatic Soft Tissue Tumors

Soft tissue tumors (STTs) include a range of benign and malignant tumors originating from soft tissues. Transarterial and percutaneous therapies are image-guided and minimally invasive approaches for managing primary and metastatic STTs. The objective of this review is to discuss transarterial and percutaneous therapies by examining the current literature, including indications, patient selection, safety, and effectiveness. Transarterial therapies (e.g., transarterial bland embolization and transarterial chemoembolization) involve the delivery of either embolic or chemotherapeutic particles using a catheter into arteries feeding the tumor, resulting in localized tumor destruction. Percutaneous therapies (e.g., radiofrequency ablation, cryoablation, irreversible electroporation, laser ablation, and magnetic resonance-guided high-intensity focused ultrasound) involve the delivery of either hot or cold temperatures, electrical current, laser, or ultrasound to specifically target tumor cells. Both therapies have been shown to be safe and effective for reducing morbidity and local control of STTs, specifically in patients who are surgically inoperable or who are unresponsive to conventional therapies. Accurate diagnosis, staging, and histological subtype identification are crucial for treatment selection. A multidisciplinary approach, a thorough understanding of tissue anatomy and surrounding structures, as well as individualized strategies based on assessment are essential for optimal patient care.

Role of interventional radiology in pain management in oncology patients

This article reviews the current evidence of interventional radiology procedures for patients suffering with debilitating cancer pain, refractory to conventional therapies. Cancer pain is notoriously difficult to treat. Up to 90% of cancer patients experience pain with 56-82% of cancer pain controlled inadequately. Cancer pain influences a patient's ability to perform normal daily activities, causes higher risk of depression, and reduces quality of life. Pain-free status has been universally voted as a "good death". Alternative minimally invasive options include nerve blocks, neurolysis, bone ablation, spine and peripheral musculoskeletal augmentation techniques, embolisation, and cordotomy with evidence highlighting improved pain control, reduced analgesic requirements, and improved quality of life. Unfortunately, awareness and availability of these procedures is limited, potentially leaving patients suffering during their remaining life. The purpose of this review is to describe the basic concepts of interventional radiology techniques for pain palliation in oncology patients. In addition, emphasis will be given upon the need for an individually tailored approach aiming to augment efficacy and safety.

Sensitivity, Specificity, and Predictive Values of Tru-Cut® Biopsy in Grading Primary Localized Myxoid Liposarcomas of the Extremities

(1) Background: Histological diagnosis and tumor grading are major prognostic and predictive factors in soft tissue sarcomas (STS), as they dictate the treatment strategies with a direct impact on patient survival. This study aims to investigate the grading accuracy, sensitivity, and specificity of Tru-Cut^® biopsy (TCB) in primary localized myxoid liposarcomas (MLs) of the extremities and its impact on patient prognosis. (2) Methods: Patients with ML undergoing TCB and a subsequent tumor resection between 2007 and 2021 were evaluated. Concordance between the preoperative assessment and definitive histology was calculated with a weighted Cohen's kappa coefficient. Sensitivity, specificity, and diagnostic accuracy were calculated. (3) Results: Of 144 biopsies, the histological grade concordance rate was 63% (Kappa 0.2819). Neoadjuvant chemotherapy and/or radiotherapy impacted concordance with a downgrading effect in high-grade tumors. Among forty patients not treated in neoadjuvant settings, the sensitivity of TCB was 57%, the specificity was 100%, and the overall predictive values of positive and negative TCB were 100% and 50%, respectively. Misdiagnosis did not impact overall survival. (4) Conclusions: TCB may underestimate ML grading due to tumor heterogeneity. Neoadjuvant ChT and/or radiotherapy are associated with pathological downgrading; however, discordance in diagnosis does not modify patient prognosis because systemic treatment decision-making also includes other variables.

Minimally Invasive Interventional Procedures for Metastatic Bone Disease: A Comprehensive Review

Metastases are the main type of malignancy involving bone, which is the third most frequent site of metastatic carcinoma, after lung and liver. Skeletal-related events such as intractable pain, spinal cord compression, and pathologic fractures pose a serious burden on patients’ quality of life. For this reason, mini-invasive treatments for the management of bone metastases were developed with the goal of pain relief and functional status improvement. These techniques include embolization, thermal ablation, electrochemotherapy, cementoplasty, and MRI-guided high-intensity focused ultrasound. In order to achieve durable pain palliation and disease control, mini-invasive procedures are combined with chemotherapy, radiation therapy, surgery, or analgesics. The purpose of this review is to summarize the recently published literature regarding interventional radiology procedures in the treatment of cancer patients with bone metastases, focusing on the efficacy, complications, local disease control and recurrence rate.

Current updates in image-guided musculoskeletal interventions

Image-guided musculoskeletal interventions are frequently done in clinical practice. Even then, the literature regarding their effectiveness is relatively scarce. Image guidance adds value over the conventional landmark-based approach and should be preferred. We hereby try to list the commonly performed procedures along with the current practice guidelines regarding their clinical indications and periprocedural care.

Percutaneous management of bone metastases: State of the art

Interventional radiology is playing an increasingly important role in the local treatment of bone metastases; this treatment is usually done with palliative intent, although in selected patients it can be done with curative intent. Two main groups of techniques are available. The first group, centered on bone consolidation, includes osteoplasty/vertebroplasty, in which polymethyl methacrylate (PMMA) is injected to reinforce the bone and relieve pain, and percutaneous osteosynthesis, in which fractures with nondisplaced or minimally bone fragments are fixed in place with screws. The second group centers on tumor ablation. tumor ablation refers to the destruction of tumor tissue by the instillation of alcohol or by other means. Thermoablation is the preferred technique in musculoskeletal tumors because it allows for greater control of ablation. Thermoablation can be done with radiofrequency, in which the application of a high frequency (450 Hz-600 Hz) alternating wave to the tumor-bone interface achieves high temperatures, resulting in coagulative necrosis. Another thermoablation technique uses microwaves, applying electromagnetic waves in an approximate range of 900 MHz-2450 MHz through an antenna that is placed directly in the core of the tumor, stimulating the movement of molecules to generate heat and thus resulting in coagulative necrosis. Cryoablation destroys tumor tissue by applying extreme cold. A more recent, noninvasive technique, magnetic resonance-guided focused ultrasound surgery (MRgFUS), focuses an ultrasound beam from a transducer placed on the patient's skin on the target lesion, where the waves' mechanical energy is converted into thermal energy (65 °C-85 °C). Treatment should be planned by a multidisciplinary team. Treatment can be done with curative or palliative intent. Once the patient is selected, a preprocedural workup should be done to determine the most appropriate technique based on a series of factors. During the procedure, protective measures must be taken and the patient must be closely monitored. After the procedure, patients must be followed up.

Percutaneous image-guided thermal ablation of bone metastases: a retrospective propensity study comparing the safety profile of radio-frequency ablation and cryo-ablation

OBJECTIVES

To retrospectively compare the safety profile of percutaneous image-guided radiofrequency ablation (RFA) and cryoablation (CA) of bone metastases (BM) with and without a propensity score analysis.

METHODS

Between January 2008 and April 2018, 274 consecutive patients (mean age 61.6 ± 12.1 years) with BM were treated at our Institution with RFA (53 patients; 66 BM) or CA (221 patients; 301 BM) and included in this study. Complications were assessed according to the type of ablation modality before and after applying a 1:1 propensity score method taking into account patient's demographics, BM features, procedural details and follow-up findings.

RESULTS

In the whole 9 BM (2.5%) reported major complications without significant difference between RFA (1/66; 1.5%) and CA (8/301; 2.7%; p = 1); 40 BM (10.9%) showed minor complications, which were more common with RFA (22/66; 33.3%) than with CA (18/301; 6.0%, p<.001) mainly due to post-procedural pain occurring more frequently with RFA than CA (20/66; 30.3% vs. 7/301; 2.3%, p<.001). Following 1:1 matching, similar results were obtained, since there were similar rates of major complications with RFA and CA (1/66 [1.5%] and 0/66 [0.0%], respectively; p = 1); and higher rates of minor complications with RFA compared to CA [33.3% (22/66) vs. 2/66 (3%); p<.001] due to preponderant postprocedural pain (90.9% [20/22] minor complications with RFA).

CONCLUSIONS

Similar low rates of major complications are expected with RFA and CA of BM. In the post-operative period, RFA appears more painful than CA, thus warranting for adoption of dedicated analgesic protocols for patients undergoing RFA.

Evolving role of minimally invasive techniques in the management of symptomatic bone metastases

PURPOSE OF REVIEW

Bone metastases are responsible for considerable morbidity, which can significantly limit a patient's quality of life. This article aims to review minimally invasive, image-guided locoregional treatments for symptomatic bone metastases as an adjunct to conventional treatment modalities.

RECENT FINDINGS

Conservative therapy and radiation therapy (RT) can be effective at addressing pain, however, they require time to achieve optimal efficacy and do not address the instability and progressive collapse of pathological fractures. Vertebral and pelvic augmentation with cement enhances structural stability and can prevent progressive collapse and deformity. Ablative therapies, including radiofrequency ablation (RFA), cryoablation, and photodynamic therapy (PDT), induce cellular destruction of tumor tissue. RFA and PDT can be combined with cement augmentation in a single sitting.

SUMMARY

Minimally invasive image-guided treatments can provide rapid pain relief, enhance mechanical stability, and improve quality of life. These treatments are associated with low complication rates and are suitable for frail patients. They can be used as companion procedures to conventional treatments, or function as an alternative for patients with radioresistant biologies or those with dose limitations from prior RT sessions.

Percutaneous management of bone metastases: state of the art

Interventional radiology is playing an increasingly important role in the local treatment of bone metastases; this treatment is usually done with palliative intent, although in selected patients it can be done with curative intent. Two main groups of techniques are available. The first group, centered on bone consolidation, includes osteoplasty / vertebroplasty, in which polymethyl methacrylate (PMMA) is injected to reinforce the bone and relieve pain, and percutaneous osteosynthesis, in which fractures with nondisplaced or minimally bone fragments are fixed in place with screws. The second group centers on tumor ablation. Tumor ablation refers to the destruction of tumor tissue by the instillation of alcohol or by other means. Thermoablation is the preferred technique in musculoskeletal tumors because it allows for greater control of ablation. Thermoablation can be done with radiofrequency, in which the application of a high frequency (450 Hz-600Hz) alternating wave to the tumor-bone interface achieves high temperatures, resulting in coagulative necrosis. Another thermoablation technique uses microwaves, applying electromagnetic waves in an approximate range of 900MHz to 2450MHz through an antenna that is placed directly in the core of the tumor, stimulating the movement of molecules to generate heat and thus resulting in coagulative necrosis. Cryoablation destroys tumor tissue by applying extreme cold. A more recent, noninvasive technique, magnetic resonance-guided focused ultrasound surgery (MRgFUS), focuses an ultrasound beam from a transducer placed on the patient's skin on the target lesion, where the waves' mechanical energy is converted into thermal energy (65°C-85°C). Treatment should be planned by a multidisciplinary team. Treatment can be done with curative or palliative intent. Once the patient is selected, a preprocedural workup should be done to determine the most appropriate technique based on a series of factors. During the procedure, protective measures must be taken and the patient must be closely monitored. After the procedure, patients must be followed up.

Polymer-assisted intratumoral delivery of ethanol: Preclinical investigation of safety and efficacy in a murine breast cancer model

Focal tumor ablation with ethanol could provide benefits in low-resource settings because of its low overall cost, minimal imaging technology requirements, and acceptable clinical outcomes. Unfortunately, ethanol ablation is not commonly utilized because of a lack of predictability of the ablation zone, caused by inefficient retention of ethanol at the injection site. To create a predictable zone of ablation, we have developed a polymer-assisted ablation method using ethyl cellulose (EC) mixed with ethanol. EC is ethanol-soluble and water-insoluble, allowing for EC-ethanol to be injected as a liquid and precipitate into a solid, occluding the leakage of ethanol upon contact with tissue. The aims of this study were to compare the 1) safety, 2) release kinetics, 3) spatial distribution, 4) necrotic volume, and 5) overall survival of EC-ethanol to conventional ethanol ablation in a murine breast tumor model. Non-target tissue damage was monitored through localized adverse events recording, ethanol release kinetics with Raman spectroscopy, injectate distribution with in vivo imaging, target-tissue necrosis with NADH-diaphorase staining, and overall survival by proxy of tumor growth. EC-ethanol exhibited decreased localized adverse events, a slowing of the release rate of ethanol, more compact injection zones, 5-fold increase in target-tissue necrosis, and longer overall survival rates compared to the same volume of pure ethanol. A single 150 μL dose of 6% EC-ethanol achieved a similar survival probability rates to six daily 50 μL doses of pure ethanol used to simulate a slow-release of ethanol over 6 days. Taken together, these results demonstrate that EC-ethanol is safer and more effective than ethanol alone for ablating tumors.

Management of aggressive fibromatosis

Aggressive fibromatosis or desmoid tumor is a rare disease resulting from fibroblasts which do not metastasize. However, desmoid tumors belong to low-grade malignant tumors since they have high potential to infiltrate surrounding tissues, causing high local recurrence rates and may affect surrounding organs, threatening life quality and expectancy. Although surgery, watch and wait, radiotherapy, chemotherapy, high intensity focused ultrasound, ablation techniques or several agents have all been frequently investigated for the treatment of this type of disease, none are deemed as standard therapy for high recurrence rates that have been supported by any data. The present review retrieved literature on treatment options for desmoids to summarize the latest treatment modalities and refine their efficacy, as well as their side effects, in order to provide a more comprehensive treatment reference for clinicians.

Feasibility of Controlling Metastatic Osseous Pain Using Three Kinds of Image-Guided Procedures for Thermal Microwave Ablation: A Retrospective Study

Objectives

To evaluate the feasibility and safety of treating painful osseous metastases using image‐guided percutaneous thermal microwave ablation.

Methods

This is a retrospective study of patients treated from December 2016 to December 2019 in one institute. A total of 50 patients (35 men, 15 women; mean age 55.24 ± 11.03 years) with 56 osseous metastatic lesions underwent image‐guided percutaneous microwave ablation. There were 7 patients with multiple and 43 patients with single metastases. The numbers of patients with primary cancer were as follows: lung, 13; liver, 17; kidney, 10; prostate, 1; breast, 3; osteosarcoma, 1; and thyroid, 5. Seventeen patients had cancer combined with soft tissue masses. The radiological images for the ablative procedures were obtained by CT, fluoroscopy with ultrasound, and fluoroscopy alone in 16, 11, and 23 patients, respectively. Pain severity was estimated using the visual analogue scale before and after treatment (1 week, 1 month, and 3 months after treatment). Radiological evaluations were performed at baseline and 3 months after the procedure.

Results

In all patients, pain reduction occurred from the first day after treatment. Pain did not recur during the 3 months of follow up. The mean total ablation time per microwave electrode was 3.99 ± 2.48 min (range, 1–15 min). The mean power of the microwave electrode was 66.40 ± 12.08 W. The average volume of bone (load‐bearing bone, such as vertebra and acetabulum) cement after ablation was 2.82 ± 0.81 mL. There were no significant differences in visual analogue scale pain scores for different imaging techniques or ablation energies. No procedure‐related complications occurred.

Conclusion

Image‐guided percutaneous thermal microwave ablation of osseous metastases relieves pain and improves mobility. CT remains the first choice for percutaneous ablation. Fluoroscopy combined with ultrasound is effective for cases with soft tissue masses; fluoroscopy is also suitable for combination with vertebroplasty. However, further investigations are required.

(A) Microwave ablation probe. (B) Temperature probe in the vertebral body and in the vertebral pedicle (parallel to the posterior margin). (C) Metastatic tumor. The thick white line of the ablation probe tip represents the source of microwave needle emission. The orange region represents the heating range of the microwave.

Image-guided percutaneous cryoablation of unresectable sacrococcygeal chordoma: Feasibility and outcome in a selected group of patients with long term follow-up

BACKGROUND

Chordoma is a rare malignant tumor of the axial skeleton. Percutaneous cryoablation (PCA) is a minimally invasive technique that allows freezing of tumors under imaging control. The purpose of our retrospective study was to investigate the outcome of PCA in a selected cohort of patients with sacrococcygeal chordoma, with a minimum of 5 years follow-up.

MATERIALS AND METHODS

Four patients were treated in 10 sessions. The mean follow-up was 57.3 months. We evaluated the feasibility, the procedure-related complications, the impact on pain control and oncological outcomes.

RESULTS

Freezing of 100% of the tumor volume was possible in 60%. Pain control was not reliably evaluable. Local recurrence occurred in 90% of the treated lesions; the mean time to progression was 8.1 months (range 1.5-16). At last follow-up, one patient had died of the disease, one of another cause and one was receiving the best supportive care. The only patient alive without the disease had received additional carbon-ion radiotherapy. The 5-year survival rate after index PCA was 50%.

CONCLUSION

Complete freezing of the tumor was technically challenging, mainly due to the complex local anatomy. Recurrence occurred in 90% of the lesions treated. PCA should be considered with caution in the curative management of sacrococcygeal chordoma.

Systematic optimization of ultrasound grayscale imaging presets and its application in abdominal scanning

Purpose

Ultrasound grayscale imaging preset optimization has often been qualitative and dependent upon vendor application specialists. This study aimed to propose a systematic approach for grayscale imaging preset optimization and apply the approach in a clinical abdominal scan setting.

Methods

A six‐step approach was detailed including identification of clinical task, adjustment of basic parameters, fine‐tuning of advanced parameters, image performance metrics confirmation, clinical evaluation and data analysis, and implementation of new presets and monitoring of clinical usage. Its application in an abdominal scanning task was described for each step with phantoms, volunteers, and software tools.

Results

Clinical image data analytics facilitated the understanding of the imaging task, relevant transducers, and target characteristics, in addition to specific requests from radiologists. Quantitative measurements were made on global image contrast and gray map function. In addition, clinically relevant phantoms and volunteer scans without and with acoustic distortion layers were involved to determine the new presets. Furthermore, phantom signal to noise ratio study and clinical evaluation using volunteers with different body habitus were utilized to confirm the superiority of the new presets. Quantitative clinical usage monitoring demonstrated successful implementation of the new presets.

Conclusions

A systematic approach for grayscale imaging preset optimization has been proposed and successfully applied for a specific clinical task. This approach was designed to be generalizable and relatively flexible, which would facilitate movement away from previous qualitative and subjective approaches.

The Role of Minimal Access Surgery in the Treatment of Spinal Metastatic Tumors

STUDY DESIGN

Literature review.

OBJECTIVE

To provide an overview of the recent advances in minimal access surgery (MAS) for spinal metastases.

METHODS

Literature review.

RESULTS

Experience gained from MAS in the trauma, degenerative and deformity settings has paved the road for MAS techniques for spinal cancer. Current MAS techniques for the treatment of spinal metastases include percutaneous instrumentation, mini-open approaches for decompression and tumor resection with or without tubular/expandable retractors and thoracoscopy/endoscopy. Cancer care requires a multidisciplinary effort and adherence to treatment algorithms facilitates decision making, ultimately improving patient outcomes. Specific algorithms exist to help guide decisions for MAS for extradural spinal metastases. One major paradigm shift has been the implementation of percutaneous stabilization for treatment of neoplastic spinal instability. Percutaneous stabilization can be enhanced with cement augmentation for increased durability and pain palliation. Unlike osteoporotic fractures, kyphoplasty and vertebroplasty are known to be effective therapies for symptomatic pathologic compression fractures as supported by high level evidence. The integration of systemic body radiation therapy for spinal metastases has eliminated the need for aggressive tumor resection allowing implementation of MAS epidural tumor decompression via tubular or expandable retractors and preliminary data exist regarding laser interstitial thermal therapy and radiofrequency ablation for tumor control. Neuronavigation and robotic systems offer increased precision, facilitating the role of MAS for spinal metastases.

CONCLUSIONS

MAS has a significant role in the treatment of spinal metastases. This review highlights the current utilization of minimally invasive surgical strategies for treatment of spinal metastases.

Anesthesia for Percutaneous Radiofrequency Tumor Ablation (PRFA): A Review of Current Practice and Techniques

Percutaneous radiofrequency ablation (PRFA) of solid tumors is a minimally invasive procedure used to treat primary or metastatic cancer lesions via needle targeted thermal energy transfer. Some of the most common tumor lesions treated using PRFA include those within the liver, lungs and kidneys. Additionally, bone, thyroid, and breast lesions can also be treated. In most cases, this procedure is performed outside of the operating room in a specialized radiology suite. As a result, the clinician must adapt in many cases to the specific environmental issues attendant to providing anesthesia outside the operating room, including the lack of availability of an anesthesia machine in some cases, and frequently a lack of adequate scavenging and other specialized monitoring and equipment. At this time, routine practice and anesthetic prescriptions for PRFA can vary widely, ranging from patients receiving local anesthesia alone, to monitored anesthesia care, to regional anesthesia, to combined regional and general anesthesia. The choice of anesthetic technique will depend on tumor location and practitioner experience. This review aims to summarize the current state of the art in terms of anesthetic techniques for patients undergoing PRFA of solid tumors.

Thermal ablation to relieve pain from metastatic bone disease: a systematic review

OBJECTIVE

To review the efficacy of percutaneous thermal ablation (TA) of bone metastases (radiofrequency ablation [RFA], microwave ablation [MWA], cryoablation [CA], and MR-guided focused ultrasound [MRgFUS]) in reducing pain in patients with advanced stage cancer.

MATERIALS AND METHODS

We searched MEDLINE/PubMed, MEDLINE In-Process, BIDS ISI, Embase, CINAHL, and the Cochrane database using the keywords "ablation," "painful," "bone," and "metastases" combined in multiple algorithms. Inclusion criteria were: original clinical studies published between 2001 and 2018; performance of RFA, MWA, CA or MRgFUS; and quantitative pain assessment before/after TA of bone metastasis.

RESULTS

Eleven papers (3 on RFA, 1 on MWA, 2 on CA, and 5 on MRgFUS) involving 364 patients were reviewed. A technical success rate of 96-100% was reported, with follow-up for up to 6 months. At baseline, pain scores ranged from 5.4 to 8, at 1-4 weeks from 0.5 to 5, and at 12 weeks from 0.3 to 4.5. Mean pain reduction compared with baseline ranged from 26 to 91% at 4 weeks and from 16% to 95% at 12 weeks. MWA treatments caused no complications, whereas MRgFUS showed the highest complication rate. The number of minor complications observed ranged from 0 to 59 (complication ratio 0-1.17), whereas the number of significant adverse effects ranged from 0 to 4 (complication ratio 0-0.04).

CONCLUSION

All techniques achieved pain relief after 1 and 3 months, in up to 91% and 95% of patients respectively. MWA showed a negligible complication rate, whereas MRgFUS is associated with a noteworthy rate of adverse events. Future studies should adopt a standardized pain reporting scale to allow for meta-analysis.

Image guidance in spine tumor surgery

Beginning with basic stereotactic operative methods in neurosurgery, intraoperative navigation and image guidance systems have since become the norm in that field. Following the introduction of image guidance into spinal surgery, there has been a dramatic increase in its utilization across disciplines and pathologies. Spine tumor surgery encompasses a wide range of complex surgical techniques and treatment strategies. Similarly to deformity correction and trauma surgery, spine navigation holds potential to improve outcomes and optimize surgical technique for spinal tumors. Recent data demonstrate the applicability of neuro-navigation in the field of spinal oncology, particularly for spinal stabilization, maximizing extent of resection and integration of minimally invasive therapies. The rapid introduction of new, less invasive, and ablative surgical techniques in spine oncology coupled with the rising incidence of spinal metastatic disease make it imperative for spine surgeons to be familiar with the indications for and limitations of imaging guidance. Herein, we provide a practical, current concepts narrative review on the use of spinal navigation in three areas of spinal oncology: (a) extent of tumor resection, (b) spinal column stabilization, and (c) focal ablation techniques.

A practical guide for planning pelvic bone percutaneous interventions (biopsy, tumour ablation and cementoplasty)

Percutaneous approaches for pelvic bone procedures (bone biopsies, tumour ablation and cementoplasty) are multiple and less well systematised than for the spine or extremities. Among the different imaging techniques that can be used for guidance, computed tomography (CT) scan is the modality of choice because of the complex pelvic anatomy. In specific cases, such as cementoplasty where real-time evaluation is a determinant, a combination of CT and fluoroscopy is highly recommended. The objective of this article is to propose a systematic approach for image-guided pelvic bone procedures, as well as to provide some technical tips. We illustrate the article with multiple examples, and diagrams of the approaches and important structures to avoid to perform these procedures safely.

TEACHING POINTS

• Pelvic bone procedures are safe to perform if anatomical landmarks are recognised. • The safest approach varies depending on the pelvic level. • CT is the modality of choice for guiding pelvic percutaneous procedures. • Fluoroscopy is recommended when real-time monitoring is mandatory. • MRI can also be used for guiding pelvic percutaneous procedures.

Percutaneous Image-Guided Ablation in the Treatment of Osseous Metastases from Non-small Cell Lung Cancer

INTRODUCTION

Percutaneous image-guided ablation is an emerging minimally invasive therapy for patients with metastatic bone disease for whom radiation therapy is ineffective or contraindicated. The purpose of this study was to examine the safety and efficacy of percutaneous ablation in achieving pain palliation and local tumor control of osseous metastases from non-small cell lung cancer (NSCLC).

METHODS

A retrospective review was performed of 76 musculoskeletal metastases in 45 patients treated with percutaneous ablation. 63% (48/76) were treated with radiofrequency ablation (RFA), 35% (27/76) with cryoablation, and 1.3% (1/76) with microwave ablation (MWA). In 70% (53/76) of cases, associated cementoplasty was performed. Primary outcomes measured were pre- and post-procedure pain scores 4 weeks after treatment and local tumor control at 3-, 6-, and 12-month follow-up.

RESULTS

Mean age of the cohort was 63.6 ± 9.5 years. Median tumor diameter was 3.60 cm (range 1.0-10.0 cm). Mean and median pain scores before treatment were 7.5 ± 2.3 and 8.0, respectively. Post-procedure, patients reported significantly decreased pain scores at 4 weeks (mean, 3.7 ± 3.5; median, 3.0; p < 0.00001). Radiographic local tumor control rates were 83% (35/42) at 3 months, 77% (23/30) at 6 months, and 68% (17/25) at 12 months after treatment. The overall complication rate was 2.6% (2/76).

CONCLUSION

Percutaneous tumor ablation is a well-tolerated, minimally invasive procedure associated with improving pain palliation and achieving local tumor control of osseous metastases from NSCLC.

LEVEL OF EVIDENCE

Level 4, case series.

How I do it-optimizing radiofrequency ablation in spinal metastases using iCT and navigation

BACKGROUND

Exact positioning of the radiofrequency ablation (RFA) probe for tumor treatment under fluoroscopic guidance can be difficult because of potentially small inaccessible lesions and the radiation dose to the medical staff in RFA. In addition, vertebroplasty (VP) can be significantly high.

METHOD

Description and workflow of RFA in spinal metastasis using iCT (intraoperative computed tomography) and 3D-navigation-based probe placement followed by VP.

CONCLUSION

RFA and VP can be successfully combined with iCT-based navigation, which leads to a reduction of radiation to the staff and optimal probe positioning due to 3D navigation.

Percutaneous Image-Guided Cryoablation in Vascular Anomalies

Understanding and management of vascular anomalies has always been intriguing. These disorders exhibit an expected pattern of clinical presentation and progression, and characteristic imaging findings. Significant progress in understanding and treating patients with vascular anomalies has been made in the past quarter century. Newer multidisciplinary domains for treating these disorders with medical drugs and less invasive image-guided or surgical procedures are constantly evolving. Vascular anomalies can exhibit aggressive tumor-like behavior resulting in recurrence or persistent symptoms after treatment. Thermal ablation has been widely used in tumor treatment. This has generated interest on using thermal ablation for treating vascular anomalies. Percutaneous image-guided cryoablation is increasingly used for this purpose as compared with other ablation technologies. Availability of small caliber cryoprobes and the ability to monitor the freeze zone in real time have made this an attractive option to interventional radiologists. These experiences are relatively new and limited. It is helpful to understand the emerging role of this technology in the treatment of vascular anomalies.

Mid-term outcomes after percutaneous cryoablation of symptomatic abdominal wall endometriosis: comparison with surgery alone in a single institution

OBJECTIVES

To compare the outcomes of percutaneous image-guided cryoablation of symptomatic abdominal wall endometriosis (AWE) versus surgery alone.

METHODS

From 2004 to 2016, cryoablation or surgery alone was performed under local (n = 5) or general anaesthesia (n = 15) for AWE in a single institution in 7 (mean age, 36.1 years) and 13 (mean age, 31.9 years) patients, respectively. Fifteen lesions were treated by cryoablation (mean size, 2.3 cm; range, 0.5-7 cm) and 16 by surgery (2.5 cm; 1.1-3.4 cm). Tolerance, efficacy and patient and procedural characteristics were compared.

RESULTS

Median follow-up was 22.5 (range, 6-42) months after cryoablation and 54 (14-149) after surgery. The median procedure and hospitalisation durations were 41.5 min (24-66) and 0.8 days (0-1) after cryoablation, and 73.5 min (35-160) and 2.8 days (1-12 days) after surgery (both P = 0.01). Three patients (23.1%) had severe complications and nine aesthetic sequels (69.2%) after surgery, none after cryoablation (P = 0.05). The median 12- and 24-month symptom free-survival rates were 100% and 66.7% (95% CI, 5.4; 94.5) after cryoablation and 92% (55.3; 98.9) after surgery at both time points (P = 0.45).

CONCLUSIONS

Cryoablation presents similar effectiveness to surgery alone for local control of AWE while reducing hospitalisation duration and complications. Any aesthetic sequels were associated with the cryoablation treatment.

KEY POINTS

• Hospitalisation is shorter after cryoablation than after surgery of abdominal wall endometriosis. • A significantly lower rate of complications is observed after cryoablation compared to surgery. • Cryoablation of abdominal wall endometriosis presents similar effectiveness to surgery alone. • A significant reduction of pain is observed 6 months after treatment. • A significant reduction of abdominal wall endometriosis is observed at 6 months.

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.

Image-Guided Spinal Ablation: A Review

The image-guided thermal ablation procedures can be used to treat a variety of benign and malignant spinal tumours. Small size osteoid osteoma can be treated with laser or radiofrequency. Larger tumours (osteoblastoma, aneurysmal bone cyst and metastasis) can be addressed with radiofrequency or cryoablation. Results on the literature of spinal microwave ablation are scarce, and thus it should be used with caution. A distinct advantage of cryoablation is the ability to monitor the ice-ball by intermittent CT or MRI. The different thermal insulation, temperature and electrophysiological monitoring techniques should be applied. Cautious pre-procedural planning and intermittent intra-procedural monitoring of the ablation zone can help reduce neural complications. Tumour histology, patient clinical-functional status and life-expectancy should define the most efficient and least disabling treatment option.

Pneumodissection for skin protection in image-guided cryoablation of superficial musculoskeletal tumours

PURPOSE

Pneumodissection is described as a simple method for preventing skin injury during cryoablation of superficial musculoskeletal tumours.

METHODS

Superficial tumour cryoablations performed from 2009 to 2015 were retrospectively reviewed. Pneumodissection was performed in 13 patients when the shortest tumour-skin distance was less than 25 mm. Indications were pain palliation (n = 9) and local tumour control (n = 4). Patients, target tumours, technical characteristics and complications up to 60 days post ablation were reviewed. The ice ball-skin distances with and without pneumodissection were compared by a paired t-test and further assessed for association with covariates using ANCOVA.

RESULTS

Technical success for ablation was 12 of 13. The mean shortest tumour-skin distance was 15.0 mm (3.2-24.5 mm). The mean thickness of pneumodissection was 9.6 mm (5.2-16.6 mm) resulting in mean elevation of skin of 3.4 mm (1.2-5.3 mm). Mean shortest ice ball-skin distance after pneumodissection was 10.5 mm (4.2-19.7 mm). No infection or systemic air embolism was noted. No intraprocedural frostbite was observed.

CONCLUSION

Pneumodissection is feasible, effective and safe in protecting the skin during image-guided cryoablation of superficial tumours.

KEY POINTS

• Frostbite during image-guided cryoablation of superficial tumours is commonly under-reported. • Frostbites are painful and may introduce infection into the superficial ablation zone. • Warm compress, saline and CO ₂ have shortcomings in protecting the skin. • Pneumodissection is free, readily available, easy to use and safe and effective.

Features and Role of Minimally Invasive Palliative Procedures for Pain Management in Malignant Pelvic Diseases: A Review

Pain is a common and debilitating symptom in pelvic cancer diseases. Failure in controlling this pain through pharmacological approaches calls for employing multimodal management and invasive techniques. Various strategies are commonly used for this purpose, including palliative radiotherapy, epidural medications and intrathecal administration of analgesic and local anesthetic drugs with pumps, and neural or plexus blockade. This review focuses on the features of minimally invasive palliative procedures (MIPPs), such as radiofrequency ablation, laser-induced thermotherapy, cryoablation, irreversible electroporation, electrochemotherapy, microwave ablation, and cementoplasty as well as their role in palliation of cancer pelvic pain. Despite the evidence of effectiveness and safety of these interventions, there are still many barriers to accessing MIPPs, including the availability of trained staff, the lack of precise criteria of indication, and the high costs.

Percutaneous tumor ablation tools: microwave, radiofrequency, or cryoablation--what should you use and why?

Image-guided thermal ablation is an evolving and growing treatment option for patients with malignant disease of multiple organ systems. Treatment indications have been expanding to include benign tumors as well. Specifically, the most prevalent indications to date have been in the liver (primary and metastatic disease, as well as benign tumors such as hemangiomas and adenomas), kidney (primarily renal cell carcinoma, but also benign tumors such as angiomyolipomas and oncocytomas), lung (primary and metastatic disease), and soft tissue and/or bone (primarily metastatic disease and osteoid osteomas). Each organ system has different underlying tissue characteristics, which can have profound effects on the resulting thermal changes and ablation zone. Understanding these issues is important for optimizing clinical results. In addition, thermal ablation technology has evolved rapidly during the past several decades, with substantial technical and procedural improvements that can help improve clinical outcomes and safety profiles. Staying up to date on these developments is challenging but critical because the physical properties underlying the different ablation modalities and the appropriate use of adjuncts will have a tremendous effect on treatment results. Ultimately, combining an understanding of the physical properties of the ablation modalities with an understanding of the thermal kinetics in tissue and using the most appropriate ablation modality for each patient are key to optimizing clinical outcomes. Suggested algorithms are described that will help physicians choose among the various ablation modalities for individual patients.

Percutaneous tumor ablation tools: microwave, radiofrequency, or cryoablation--what should you use and why?

Image-guided thermal ablation is an evolving and growing treatment option for patients with malignant disease of multiple organ systems. Treatment indications have been expanding to include benign tumors as well. Specifically, the most prevalent indications to date have been in the liver (primary and metastatic disease, as well as benign tumors such as hemangiomas and adenomas), kidney (primarily renal cell carcinoma, but also benign tumors such as angiomyolipomas and oncocytomas), lung (primary and metastatic disease), and soft tissue and/or bone (primarily metastatic disease and osteoid osteomas). Each organ system has different underlying tissue characteristics, which can have profound effects on the resulting thermal changes and ablation zone. Understanding these issues is important for optimizing clinical results. In addition, thermal ablation technology has evolved rapidly during the past several decades, with substantial technical and procedural improvements that can help improve clinical outcomes and safety profiles. Staying up to date on these developments is challenging but critical because the physical properties underlying the different ablation modalities and the appropriate use of adjuncts will have a tremendous effect on treatment results. Ultimately, combining an understanding of the physical properties of the ablation modalities with an understanding of the thermal kinetics in tissue and using the most appropriate ablation modality for each patient are key to optimizing clinical outcomes. Suggested algorithms are described that will help physicians choose among the various ablation modalities for individual patients.

Image-guided cryoablation for the treatment of painful musculoskeletal metastatic disease: a single-center experience

PURPOSE

The role of image-guided thermal ablation techniques for the nonoperative local management of painful osseous metastatic disease has expanded during recent years, and several advantages of cryoablation in this setting have emerged. The purpose of this study is to retrospectively evaluate and report a single-center experience of CT-guided percutaneous cryoablation in the setting of painful musculoskeletal metastatic disease.

METHODS

This study was approved by the institutional review board and is compliant with the Health Insurance Portability and Accountability Act. Electronic medical records of all patients who underwent percutaneous image-guided palliative cryoablation at our institution were reviewed (n = 61). An intent-to-treat analysis was performed. Records were reviewed for demographic data and anatomical data, primary tumor type, procedure details, and outcome-including change in analgesic requirements (expressed as morphine equivalent dosages), pain scores (utilizing the clinically implemented visual analog scale), subsequent therapies (including radiation and/or surgery), and complications during the 24 h following the procedure and at 3 months. Patients were excluded (n = 7) if data were not retrospectively identifiable at the defined time points.

RESULTS

Fifty-four tumors were ablated in 50 patients. There were statistically significant decreases in the median VAS score and narcotic usage at both 24 h and 3 months (p < 0.000). Six patients (11%) incurred complications related to their therapy. Two patients had no relief at 24 h, of which both reported worsened pain at 3 months. One patient had initial relief but symptom recurrence at 3 months. Four patients went on to have radiation therapy of the ablation site at some point following the procedure.

CONCLUSIONS

CT-guided cryoablation is a safe, effective, reproducible procedural option for the nonoperative local treatment of painful musculoskeletal metastatic disease.

Bone and soft tissue ablation

Bone and soft tissue tumor ablation has reached widespread acceptance in the locoregional treatment of various benign and malignant musculoskeletal (MSK) lesions. Many principles of ablation learned elsewhere in the body are easily adapted to the MSK system, particularly the various technical aspects of probe/antenna design, tumoricidal effects, selection of image guidance, and methods to reduce complications. Despite the common use of thermal and chemical ablation procedures in bone and soft tissues, there are few large clinical series that show longitudinal benefit and cost-effectiveness compared with conventional methods, namely, surgery, external beam radiation, and chemotherapy. Percutaneous radiofrequency ablation of osteoid osteomas has been evaluated the most and is considered a first-line treatment choice for many lesions. Palliation of painful metastatic bone disease with thermal ablation is considered safe and has been shown to reduce pain and analgesic use while improving quality of life for cancer patients. Procedure-related complications are rare and are typically easily managed. Similar to all interventional procedures, bone and soft tissue lesions require an integrated approach to disease management to determine the optimum type of and timing for ablation techniques within the context of the patient care plan.

Percutaneous bone lesion ablation

Benign tumors and metastatic bone lesions can be treated by ablation techniques performed either alone or in combination with other percutaneous techniques. Ablation techniques include ethanol or acetic acid injection and thermal ablation by means of energy deposition [including laser, radiofrequency, microwave, cryoablation, radiofrequency ionization and magnetic resonance (MR)-guided high-intensity focused ultrasound (HIFU)]. Goal definition of the therapy is crucial: ablation techniques can be proposed as curative treatments in benign bone tumors or oligometastatic disease (<3 lesions). Alternatively, these techniques can be proposed as palliative treatments aiming at reduction of pain, local control of the disease and tumor decompression. Depending on the lesion's location ablation can be combined with cementation with or without further metallic augmentation; local tumor control can be enhanced by combining ablation with transarterial bland embolization or chemoembolization. Thermal ablation of bone and soft tissues is characterized by high success and relatively low rates of potential complications, mainly iatrogenic thermal damage of surrounding sensitive structures. Successful thermal ablation requires a sufficient ablation volume and thermal protection of the surrounding vulnerable structures. This article will describe the general principles governing ablation and the mechanism of action for each technique and in addition will review the literature about safety and effectiveness of percutaneous imaging-guided ablation for benign and malignant (primary and metastatic) lesions.

Percutaneous image-guided ablation of bone and soft tissue tumours: a review of available techniques and protective measures

Background

Primary or metastatic osseous and soft tissue lesions can be treated by ablation techniques.

Methods

These techniques are classified into chemical ablation (including ethanol or acetic acid injection) and thermal ablation (including laser, radiofrequency, microwave, cryoablation, radiofrequency ionisation and MR-guided HIFU). Ablation can be performed either alone or in combination with surgical or other percutaneous techniques.

Results

In most cases, ablation provides curative treatment for benign lesions and malignant lesions up to 3 cm. Furthermore, it can be a palliative treatment providing pain reduction and local control of the disease, diminishing the tumour burden and mass effect on organs. Ablation may result in bone weakening; therefore, whenever stabilisation is undermined, bone augmentation should follow ablation depending on the lesion size and location.

Conclusion

Thermal ablation of bone and soft tissues demonstrates high success and relatively low complication rates. However, the most common complication is the iatrogenic thermal damage of surrounding sensitive structures. Nervous structures are very sensitive to extremely high and low temperatures with resultant transient or permanent neurological damage. Thermal damage can cause normal bone osteonecrosis in the lesion’s periphery, surrounding muscular atrophy and scarring, and skin burns. Successful thermal ablation requires a sufficient ablation volume and thermal protection of the surrounding vulnerable structures.

Teaching points

• Percutaneous ablations constitute a safe and efficacious therapy for treatment of osteoid osteoma.

• Ablation techniques can treat painful malignant MSK lesions and provide local tumour control.

• Thermal ablation of bone and soft tissues demonstrates high success and low complication rates.

• Nerves, cartilage and skin are sensitive to extremely high and low temperatures.

• Successful thermal ablation occasionally requires thermal protection of the surrounding structures.