Percutaneous ablation of bone tumors

Selective Effects of Cold Atmospheric Plasma on Bone Sarcoma Cells and Human Osteoblasts

BACKGROUND

The use of cold atmospheric plasma (CAP) in oncology has been intensively investigated over the past 15 years as it inhibits the growth of many tumor cells. It is known that reactive oxidative species (ROS) produced in CAP are responsible for this effect. However, to translate the use of CAP into medical practice, it is essential to know how CAP treatment affects non-malignant cells. Thus, the current in vitro study deals with the effect of CAP on human bone cancer cells and human osteoblasts. Here, identical CAP treatment regimens were applied to the malignant and non-malignant bone cells and their impact was compared.

METHODS

Two different human bone cancer cell types, U2-OS (osteosarcoma) and A673 (Ewing's sarcoma), and non-malignant primary osteoblasts (HOB) were used. The CAP treatment was performed with the clinically approved kINPen MED. After CAP treatment, growth kinetics and a viability assay were performed. For detecting apoptosis, a caspase-3/7 assay and a TUNEL assay were used. Accumulated ROS was measured in cell culture medium and intracellular. To investigate the influence of CAP on cell motility, a scratch assay was carried out.

RESULTS

The CAP treatment showed strong inhibition of cell growth and viability in bone cancer cells. Apoptotic processes were enhanced in the malignant cells. Osteoblasts showed a higher potential for ROS resistance in comparison to malignant cells. There was no difference in cell motility between benign and malignant cells following CAP treatment.

CONCLUSIONS

Osteoblasts show better tolerance to CAP treatment, indicated by less affected viability compared to CAP-treated bone cancer cells. This points toward the selective effect of CAP on sarcoma cells and represents a further step toward the clinical application of CAP.

Radiofrequency Ablation of Spine Metastases: A Clinical and Technical Approach

Percutaneous radiofrequency ablation (RFA) is an integral component of the multidisciplinary treatment algorithm for both local tumor control and palliation of painful spine metastases. This minimally invasive therapy complements additional treatment strategies, such as pain medications, systemic chemotherapy, surgical resection, and radiotherapy. The location and size of the metastatic lesion dictate preprocedure planning and the technical approach. For example, ablation of lesions along the spinal canal, within the posterior vertebral elements, or with paraspinal soft tissue extension are associated with a higher risk of injury to adjacent spinal nerves. Additional interventions may be indicated in conjunction with RFA. For example, ablation of vertebral body lesions can precipitate new, or exacerbate existing, pathologic vertebral compression fractures that can be prevented with vertebral augmentation. This article reviews the indications, clinical work-up, and technical approach for RFA of spine metastases.

Percutaneous cryoablation of benign bony tumours of the mandible

Treatment of bony tumours of the oral and maxillofacial area usually involve resection. However, access to certain areas may be difficult because of the size or site of the tumour. A poor view of the lesion during operation is another limiting factor, which can lead to incomplete resection in difficult cases. Percutaneous cryoablation is a common procedure for treating benign and malignant bony lesions outside the oral and maxillofacial area, but has to our knowledge never been used as a stand-alone treatment as we describe here. In 2016, three patients with benign bony tumours of the mandible (one a keratocyst, one an angiofibroma, and one a giant cell granuloma) were treated with one session of percutaneous cryoablation. Outcomes were monitored with computed tomography or magnetic resonance imaging at one year. No patient had a procedure-related complication, and there were no other complications. Radiological controls showed complete recovery. Percutaneous cryoablation seems to be an interesting and valuable alternative to resection for bony lesions with its limited access and high operative morbidity.

Thermal-ablation of vertebral metastases prevents adverse events in patients with differentiated thyroid carcinoma

PURPOSE

To evaluate a strategy that used thermal-ablation of vertebral metastases (VM) to prevent vertebral related events (VRE) in patients with differentiated thyroid cancer (DTC).

METHODS

This single center study retrospectively reviewed records and post-operative imaging of all DTC patients treated with thermal-ablation for asymptomatic VMs. Rate of local tumor control at first post-operative imaging, 12 and 24 months after thermal-ablation and rate of VREs at 12 and 24 months among the treated VMs were reported. New VMs that occurred during the follow-up and were not considered for additional thermal-ablation were moniroted and VREs were reported.

RESULTS

Thermal-ablation was used to achieve local control of 41 VMs in 28 patients. Median post-treatment follow-up was 22 months [range: 12-80] and the mean delay for first post-operative imaging was 2 months [range: 0.6-7.5]. Local control at first post-operative imaging, 12 and 24 months was achieved in 87.8%, 82.9% and 75.6%, respectively. Among the treated VMs the rates of VRE was 7.3% at 2 years, significantly lower if local control was achieved at first post-operative imaging than if it was not (0% vs 30%, p = 0.011, OR = 0.184 [95%CI = 0.094-0.360]). After thermal-ablation procedures, 19 news VMs occurred in 11 patients (39.2%) with a median interval of 8 months [range 1-26] and remained untreated. Among these untreated VMs, the rate of VREs at 2 years was significantly higher compared to the treated VMs: (36.8% vs. 7.3%, p = 0.008, OR = 0.135, [95%CI = 0.030-0.607]).

CONCLUSION

local tumor control of VMs using thermal-ablation decreases the risk of VREs in DTC patients.

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.

Successful treatment with cryoablation in a patient with bone metastasis in the mid-shaft femur: a case report

Background: Treatment of metastatic bone tumors is challenging due to the morbidity associated with patients with metastasis. The present case report described a patient with successful treatment of bone metastasis using cryoablation with plate and cementation to prevent fracture for bone metastasis of leiomyosarcoma in the mid-shaft of the femur.

Case report: The metastatic tumor was located at intramedullary lesion of the femur. At first, cryoablation was performed under local anesthesia. After one week after cryoablation, curettage and fixation with plate and cementation were performed to prevent fracture. Tumor cells were not observed in the histopathological findings of the curettage tissue. Four years after cryoablation, there was no recurrence and the patient could walk without any support.

Conclusion: We suggest that a tumor with limited cancellous bone and of a small size may undergo cryoablation. The prevention of fracture after cryoablation should be considered.

Thermal Ablation of Bone Metastases

Image-guided, minimally invasive, percutaneous thermal ablation of bone metastases has unique advantages compared with surgery or radiation therapy. Thermal ablation of osseous metastases may result in significant pain palliation, prevention of skeletal-related events, and durable local tumor control. This article will describe current thermal ablation techniques utilized to treat bone metastases, summarize contemporary evidence supporting such thermal ablation treatments, and outline an approach to percutaneous ablative treatment.

Integrated CT-Fluoroscopy Equipment: Improving the Interventional Radiology Approach and Patient Experience for Treatment of Musculoskeletal Malignancies

Integrated CT-fluoroscopy equipment augments the comprehensive approach to the treatment of musculoskeletal (MSK) malignancy by interventional radiology techniques. As the role of minimally invasive treatment expands to meet the highly variable presentation of MSK malignancy, creative solutions to treatment challenges are required to improve locoregional tumor control and durability of pain palliation. Challenges to effective treatment can often be attributed to a combination of aggressive tumor biology, large size, forbidding location, and adverse vascularity. In these cases, a tailored treatment approach may necessitate the application of multiple interventional radiology (IR) techniques that require different image guidance capabilities. Integrated CT-fluoroscopy equipment provides the means to leverage both imaging modalities within the same procedural setting to facilitate the simultaneous application of multiple synergistic treatments and protective measures. This article examines the potential role of hybrid units in the IR treatment of challenging MSK malignancies as a means to empower a paradigm transition for a more comprehensive and patient-tailored approach.

Case-report: Metastases in a low-stage middle-graded HCC in cleared HCV infection, non-cirrhotic liver: Surgical therapy

INTRODUCTION

Hepatocellular carcinoma (HCC) is rare in non-cirrhotic liver. Achievement of sustained virological response (SVR) reduces even more the risk.

PRESENTATION OF CASE

Liver resection for small HCC was performed in cleared HCV infection non-cirrhotic 62-year-old man. Methacronous oligometastatic recurrences in intolerant to Nexavar® side-effects patient, were treated by multiple innovative microinvasive approaches: bilateral laparoscopic adrenalectomy, thoracic wall resection, laparoscopic sacrum cryoablation combined with hadron-therapy.

DISCUSSION

Therapies allowed the patient to lead 6 years satisfying QoL with only a small residual presacral disease stable at 8 months.

CONCLUSION

Microinvasive surgery may be a valid resource of therapy in indolent HCC limited distant recurrences.

Prevention of serious skeletal-related events by interventional radiology techniques in patients with malignant paraganglioma and pheochromocytoma

PURPOSE

Bone metastases (BM) and skeletal-related events (SRE) are frequent in patients with malignant pheochromocytoma and paraganglioma (PPM) and the best modality of prevention unknown. The role of interventional radiology (IR) techniques for the prevention of SRE in the multidisciplinary management of malignant PPM has not been evaluated in that setting.

METHODS

Single referral center retrospective review of all patients with malignant PPM with BM from 2000 to 2016. The primary endpoint was the time to first serious SRE (TTSRE). At time of inclusion, patients with high bone tumor burden disease were defined as those having more than five BM with the biggest exceeding 2 cm (Group A) and patients with moderate bone tumor burden disease were defined as those having five or less BM or no BM exceeding 2 cm (Group B).

RESULTS

A total of 28 patients were included in this study. Thirteen were treated by IR techniques for prevention of first serious SRE. After a median follow-up of 48.2 months, the median TTSRE was not reached in patients treated by IR techniques and was 26.0 months in patients without IR procedures (p = .058). When comparing patients in group B, TTSRE was significantly higher in patients treated by IR (10 patients) when compared to patients without IR procedures (12 patients) (p = .021).

CONCLUSIONS

IR techniques may help to delay the occurrence of first serious SRE in patients with malignant PPM with moderate bone tumor burden disease. Prospective studies are expected to confirm these results.

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.

Chemotherapy and tyrosine-kinase inhibitors for medullary thyroid cancer

Medullary thyroid cancer (MTC) represents 3% of all clinical thyroid cancers and arises from thyroid C cells that produce calcitonin. Locally advanced or metastatic MTC requires a careful work-up including measurement of serum calcitonin and carcinoembryonic antigen, determination of their doubling time and comprehensive imaging to determine the extent of the disease, its aggressiveness, and the need for treatment. Cytotoxic chemotherapy can control tumor burden in some patients with response rates of around 20% in old series. For the last 10 years, systemic therapy for MTC patients with large tumor burden and documented progression of the disease has involved the use of tyrosine kinase inhibitors targeting VEGFR and ret. Progression-free survival benefits have been demonstrated for both vandetanib and cabozantinib, as compared to placebo. Although these molecules are effective, they also have specific toxicity profiles which require a thorough clinical management in specialized centers. In the present review, we describe the work-up and treatment modalities of patients with advanced or metastatic medullary thyroid cancer with a focus on chemotherapy and targeted therapy results.

Thermal Conductivity of Human Bone in Cryoprobe Freezing as Related to Density

Cryoprobes create localized cell destruction through freezing. Bone is resistant to temperature flow but is susceptible to freezing necrosis at warmer temperatures than tumor cells. Few studies have determined the thermal conductivity of human bone. No studies have examined conductivity as related to density. The study goal was to examine thermal conductivity in human bone while comparing differences between cancellous and cortical bone. An additional goal was to establish a relationship between bone density and thermal conductivity. Six knee joints from 5 cadavers were obtained. The epiphyseal region was sliced in half coronally prior to inserting an argon-circulating cryoprobe directed away from the joint line. Thermistor thermometers were placed perpendicularly at measured increments, and the freezing cycle was recorded until steady-state conditions were achieved. For 2 cortical samples, the probe was placed intramedullary in metaphyseal samples and measurements were performed radially from the central axis of each sample. Conductivity was calculated using Fournier's Law and then plotted against measured density of each sample. Across samples, density of cancellous bone ranged from 0.86 to 1.38 g/mL and average thermal conductivity ranged between 0.404 and 0.55 W/mK. Comparatively, cortical bone had a density of 1.70 to 1.86 g/mL and thermal conductivity of 0.0742 to 0.109 W/mK. A strong 2-degree polynomial correlation was seen (R²=0.8226, P<.001). Bone is highly resistant to temperature flow. This resistance varies and inversely correlates strongly with density. This information is clinically relevant to maximize tumor ablation while minimizing morbidity through unnecessary bone loss and damage to surrounding structures. [Orthopedics. 2017; 40(2):90-94.].

Prospective pilot study of CT-guided microwave ablation in the treatment of osteoid osteomas

PURPOSE

The aims of this work were to assess the feasibility and efficacy of CT-guided microwave ablation (MWA) in the treatment of osteoid osteomas (OOs).

MATERIALS AND METHODS

Thirteen consecutive patients (range 11-31 years old) presenting with OO were prospectively included and treated by CT-guided MWA. Power and duration of MWA were both recorded. The patient's pain was assessed using a numeric pain rating scale (NRS), and side effects were recorded during procedures, after 1 day, 7 days and 1 month. The nidus vascularization and the volume of necrosis induced by MWA were assessed using contrast-enhanced MRI. Success was defined as the complete relief of the patient's pain 1 month after the first procedure, associated with necrosis of the nidus on follow-up MRI.

RESULTS

The success rate was up to 92.3% (12/13). At 1 day, 7 days and 1 month, the median NRSs were respectively 5 [interquartile range (IQR) 2-5], 0 (IQR 0-1) and 0 (IQR 0-0). Side effects observed were one partial and self-resolving lesion of a sensory branch of the radial nerve and two skin burns. The median power of the MWA used was 60 W (IQR 50-60) with a 1.5-min duration (IQR 1-2), leading to MWA-induced necrosis measuring on average 23 × 15 × 16 mm.

CONCLUSION

CT-guided MWA of OO has a success rate that appears to be almost similar to that of laser or radiofrequency ablation, but care must be taken to prevent nerve or skin lesions.

Percutaneous low-pressure bone stenting to control cement deposition in extensive lytic lesions

OBJECTIVE

To evaluate low-pressure bone stenting combined with cementoplasty in extensive lytic lesions.

METHODS

A single-centre study involving four consecutive patients (four women) with extensive lytic tumours was performed. The average age was 65 years. Surgical treatment was not indicated or not wished for by the patients. Institutional review board approval and informed consent were obtained. Percutaneous consolidation was performed by an interventional radiologist under fluoroscopy guidance. Follow-up was assessed using the visual analogue scale (VAS).

RESULTS

Under general (n = 2) or local (n = 2) anaesthesia, five 11-gauge bone biopsy needles were advanced in four lesions. Five auto-expandable uncovered stents (10-14 mm diameter and 40-60 mm long) were inserted. In all cases, bone cement was successfully placed into the tumours. The volume of cement that was injected through the cannulas into the stents was 5-10 mL. Using VAS, pain decreased from more than 9/10 preoperatively to less than 2/10 after the procedure for all patients (p < 0.05). No complications occurred during the follow-up (8-19 months).

CONCLUSION

This study suggests that cementoplasty combined with low-pressure bone stenting could allow effective bone stabilization resulting in pain relief.

KEY POINTS

• Low-pressure bone stenting is possible. • This technique improves cement injection control. • The procedure allows effective bone stabilization resulting in pain relief.

Management of advanced medullary thyroid cancer

Medullary thyroid cancer arises from calcitonin-producing C-cells and accounts for 3-5% of all thyroid cancers. The discovery of a locally advanced medullary thyroid cancer that is not amenable to surgery or of distant metastases needs careful work-up, including measurement of serum calcitonin and carcinoembryonic antigen (and their doubling times), in addition to comprehensive imaging to determine the extent of the disease, its aggressiveness, and the need for any treatment. In the past, cytotoxic chemotherapy was used for treatment but produced little benefit. For the past 10 years, tyrosine kinase inhibitors targeting vascular endothelial growth factor receptors and RET (rearranged during transfection) have been used when a systemic therapy is indicated for large tumour burden and documented disease progression. Vandetanib and cabozantinib have shown benefits on progression-free survival compared with placebo in this setting, but their toxic effect profiles need thorough clinical management in specialised centres. This Review describes the management and treatment of patients with advanced medullary thyroid cancer with emphasis on current targeted therapies and perspectives to improve patient care. Most treatment responses are transient, emphasising that mechanisms of resistance need to be better understood and that the efficacy of treatment approaches should be improved with combination therapies or other drugs that might be more potent or target other pathways, including immunotherapy.

The Effect of Irreversible Electroporation on the Femur: Experimental Study in a Rabbit Model

Irreversible electroporation (IRE) is a novel ablation method that has been tested in humans with lung, prostate, kidney, liver, lymph node and presacral cancers. As a new non-thermal treatment, the use of IRE to ablate tumors in the musculoskeletal system might reduce the incidence of fractures. We aimed to determine the ablation threshold of cortical bone and to evaluate the medium- and long-term healing process and mechanical properties of the femur in a rabbit model post-IRE ablation. The ablation threshold of cortical bone was between 1090 V/cm and 1310 V/cm (120 pulses). IRE-ablated femurs displayed no detectable fracture but did exhibit signs of recovery, including osteoblast regeneration, angiogenesis and bone remodeling. In the ablation area, revascularization appeared at 4 weeks post-IRE. Osteogenic activity peaked 8 weeks post-IRE and remained high at 12 weeks. The mechanical strength decreased briefly 4 weeks post-IRE but returned to normal levels within 8 weeks. Our experiment revealed that IRE ablation preserved the structural integrity of the bone cortex, and the ablated bone was able to regenerate rapidly. IRE may hold unique promise for in situ bone tissue ablation because rapid revascularization and active osteogenesis in the IRE ablation area are possible.