Musculoskeletal Oncologic Interventions: Proceedings from the Society of Interventional Radiology and Society of Interventional Oncology Research Consensus Panel

Directional microwave ablation in spine: experimental assessment of computational modeling

BACKGROUND

Despite the theoretical advantages of treating metastatic bone disease with microwave ablation (MWA), there are few reports characterizing microwave absorption and bioheat transfer in bone. This report describes a computational modeling-based approach to simulate directional microwave ablation (dMWA) in spine, supported by ex vivo and pilot in vivo experiments in porcine vertebral bodies.

MATERIALS AND METHODS

A 3D computational model of microwave ablation within porcine vertebral bodies was developed. Ex vivo porcine vertebra experiments using a dMWA applicator measured temperatures approximately 10.1 mm radially from the applicator in the direction of MW radiation (T1) and approximately 2.4 mm in the contra-lateral direction (T2). Histologic assessment of ablated ex vivo tissue was conducted and experimental results compared to simulations. Pilot in vivo experiments in porcine vertebral bodies assessed ablation zones histologically and with CT and MRI.

RESULTS

Experimental T1 and T2 temperatures were within 3-7% and 11-33% of simulated temperature values. Visible ablation zones, as indicated by grayed tissue, were smaller than those typical in other soft tissues. Posthumous MRI images of in vivo ablations showed hyperintensity. In vivo experiments illustrated the technical feasibility of creating directional microwave ablation zones in porcine vertebral body.

CONCLUSION

Computational models and experimental studies illustrate the feasibility of controlled dMWA in bone tissue.

Current role and future applications of image-guided interventional procedures in musculoskeletal oncology - A narrative review

Background

Musculoskeletal (MSK) image-guided interventional procedures have been increasingly used in and remain crucial in the diagnosis and treatment of musculoskeletal tumours.

Aims

In this article, we aim to describe commonly performed interventional procedures in the subspeciality of MSK oncology drawing experience from our tertiary referral centre. Recent advances, emerging techniques and future applications of image-guided interventional procedures in the field of MSK oncology are highlighted.

Material and methods

A retrospective search using the keyword 'musculoskeletal system', 'neoplasms', 'biopsy', and 'interventional radiology' was performed at our tertiary care oncology orthopaedic referral centre radiology database. The radiology images were collected from our Picture Archiving and Communication System (PACS) and Radiology Information System (RIS). Electronic Patient Records, histopathology laboratory records and patient characteristics were collaborated to generate this narrative experience at our centre.

Results

Image-guided interventional procedures have been utilised in a spectrum of primary and secondary MSK tumours. Current applications include diagnosis of bone and soft tissue MSK neoplastic lesions with biopsies, thermal, cryotherapy and Radiofrequency ablations and augmentation procedures.

Conclusion

Musculoskeletal (MSK) image-guided interventions have increasing applications in the diagnosis, management, treatment and monitoring of patients with MSK tumours. The emergence of newer imaging technologies with enhanced skills of interventional radiologists will allow a range of therapeutic MSK interventions in both effective control of primary lesions and palliative care of metastatic lesions.

Management of giant cell tumors of the distal radius

Background

The distal radius is the most common location for giant cell tumors (GCT) in the upper extremity. Treatment should balance the goals of maximizing function and minimizing recurrence and other complications. Given the complexity in surgical treatment, various techniques have been described without clear standards of treatment.

Objectives

The purpose of this review is to provide an overview of evaluation of patients presenting with GCT of the distal radius, discuss management, and provide an updated summary on outcomes of treatment options.

Conclusion

Surgical treatment should consider tumor Grade, involvement of the articular surface, and patient-specific factors. Options include intralesional curettage and en bloc resection with reconstruction. Within reconstruction techniques, radiocarpal joint preserving and sparing procedures can be considered. Campanacci Grade 1 tumors can be successfully treated with joint preserving procedures, whereas for Campanacci Grade 3 tumors consideration should be given to joint resection to prevent recurrence. Treatment of Campanacci Grade 2 tumors is debated in the literature. Intralesional curettage and adjuvants can successfully treat cases where the articular surface can be preserved, while en-bloc resection should be used in cases where the articular surface cannot undergo aggressive curettage. A variety of reconstructive techniques are used for cases needing resection, with no clear gold standard. Joint sparing procedures preserve motion at the wrist joint, whereas joint sacrificing procedures preserve grip strength. Choice of reconstructive procedure should be made based on patient-specific factors, considering relative functional outcomes, complications, and recurrence rates.

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.

Embolization in Pediatric Patients: A Comprehensive Review of Indications, Procedures, and Clinical Outcomes

Embolization in pediatric patients encompasses a large spectrum of indications, ranging from the elective treatment of congenital diseases of the cardiovascular system to the urgent management of acute hemorrhagic conditions. In particular, the endovascular treatment of central and peripheral vascular malformations and hypervascular tumors represents a wide chapter for both congenital and acquired situations. Thanks to the progressive availability of low-profile endovascular devices and new embolic materials, the mini-invasive approach has gradually overtaken surgery. In this review, the main embolization procedures will be illustrated and discussed, with a focus on clinical indications and expected outcomes. The most recent mini-invasive techniques will be described, with hints on the cutting-edge devices and embolic materials.

Feasibility and safety of percutaneous image-guided cryoablation of abdominal wall endometriosis

PURPOSE

To evaluate the feasibility and safety of percutaneous image-guided cryoablation of abdominal wall endometriosis (AWE).

MATERIALS AND METHODS

A retrospective review of percutaneous cryoablation (CT or MR) of AWE was performed from January 2018 to December 2020. Eighteen patients were identified from an internal percutaneous ablation database. Technical success, complications, and outcomes were analyzed according to standard nomenclature.

RESULTS

Patients comprised 18 females (mean age 36.9 years) who underwent 18 cryoablation procedures to treat 23 AWE deposits. Three of the 18 cases were performed under MR guidance, while the remaining 15 employed CT guidance. Technical success was achieved in all 18 cases (100%). Fifteen of 18 patients (83%) had biopsy proven AWE deposits prior to treatment. Hydrodisplacement was used to displace adjacent bowel, bladder, or neurovascular structures in 13/18 cases (72%). The mean number of probes used per case was 3. Sixteen of 23 (70%) of AWE deposits had imaging follow-up (median 85 days). Of the 16 lesions with imaging follow-up, 15 (94%) demonstrated no residual enhancement or T1 hyperintensity at the treatment site and 1 lesion (6%) demonstrated residual/progressive disease. At clinical follow-up, 13 of 14 (93%) patients reported improvement in AWE-related symptoms. Eleven patients had clinically documented pain scores before and after ablation and all demonstrated substantial symptomatic improvement. No society of interventional radiology (SIR) major complications were observed.

CONCLUSIONS

Percutaneous cryoablation of AWE is feasible with a favorable safety profile. Further longitudinal studies are needed to document durable response over time.

Percutaneous cryoablation for desmoid fibromatosis: initial experience at a UK centre

AIM

To report the first UK experience of cryoablation in desmoid fibromatosis (DF) with particular focus on technique, safety, and efficacy.

MATERIALS AND METHODS

Patients were selected at multidisciplinary tumour board meetings at a specialist cancer hospital. Radiation dose, procedure duration, and number of cryoprobes were compared for small versus large tumours (>10 cm long axis). Response at magnetic resonance imaging (MRI) was evaluated using different criteria, and percentage agreement with clinical response as assessed in oncology clinic calculated.

RESULTS

Thirteen procedures were performed in 10 patients (eight women, median age 51 years, IQR 42-69 years) between February 2019 and August 2021. Procedures for large tumours had higher radiation dose (2,012 ± 1,012 versus 1,076 ± 519 mGy·cm, p=0.048) used more cryoprobes (13 ± 7 versus 4 ± 2, p=0.009), and were more likely to have residual unablated tumour (38 ± 37% versus 7.5 ± 10%, p=0.045). Adverse events were minor apart from one transient radial nerve palsy. Eight of 10 patients had symptomatic benefit at clinical follow-up (median 353 days, IQR 86-796 days), and three started systemic therapy mean 393 days later. All patients who had complete ablation demonstrated symptomatic response, with no instances of repeat treatment, recurrence, or need for systemic therapy during the study period. All progression occurred outside ablation zones.

CONCLUSION

Cryoablation for symptomatic DF is a reproducible technique with low, transient toxicity, where one or two treatments can achieve a meaningful response. Where possible, the ablation ice ball should fully cover DF tumours.