Percutaneous Vertebral Augmentation and Thermal Ablation in Patients with Spinal Metastases.

Vertebral augmentation and thermal ablation offer radiologists a robust minimally invasive option for treatment of patients with spinal metastases. Such interventions are commonly combined and have proved safe and effective in the management of selected patients with vertebral metastases with durable treatment effects. Special attention to procedure techniques including choice of vertebral augmentation technique, choice of ablation modality, and thermal protection is essential for improved patient outcomes. This article provides a review of the most recent advances in vertebral augmentation and thermal ablation for the treatment of spinal metastases.

Risk of adjacent level fracture after percutaneous vertebroplasty and kyphoplasty vs natural history for the management of osteoporotic vertebral compression fractures: a network meta-analysis of randomized controlled trials.

OBJECTIVES: Percutaneous vertebroplasty and kyphoplasty are common interventions for osteoporotic vertebral compression fractures. However, there is concern about an increased risk of adjacent-level fractures after treatment. This study aimed to compare the risk of adjacent-level fractures after vertebroplasty and kyphoplasty with the natural history after osteoporotic vertebral compression fractures. MATERIALS AND METHODS: A network meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate the risk of adjacent-level fractures after vertebroplasty and kyphoplasty compared to the natural history after osteoporotic vertebral compression fractures. Frequentist network meta-analysis was conducted using the "netmeta" package, and heterogeneity was assessed using Q statistics. The pooled risk ratio (RR) and 95% confidence intervals (CI) were calculated using random effects. RESULTS: Twenty-three RCTs with a total of 2838 patients were included in the analysis. The network meta-analysis showed comparable risks of adjacent-level fractures between vertebroplasty, kyphoplasty, and natural history after osteoporotic vertebral compression fractures with a mean follow-up of 21.2 (range: 3-49.4 months). The pooled RR for adjacent-level fractures after kyphoplasty compared to natural history was 1.35 (95% CI, 0.78-2.34, p = 0.23) and for vertebroplasty compared to natural history was 1.16 (95% CI, 0.62-2.14) p = 0.51. The risk of bias assessment showed a low to moderate risk of bias among included RCTs. CONCLUSION: There was no difference in the risk of adjacent-level fractures after vertebroplasty and kyphoplasty compared to natural history after osteoporotic vertebral compression fractures. The inclusion of a large patient number and network meta-analysis of RCTs serve evidence-based clinical practice. CLINICAL RELEVANCE STATEMENT: The risk of adjacent-level fracture following percutaneous vertebroplasty or kyphoplasty is similar to that observed in the natural history after osteoporotic vertebral compression fractures. KEY POINTS: RCTs have examined the risk of adjacent-level fracture after intervention for osteoporotic vertebral compression fractures. There was no difference between vertebroplasty and kyphoplasty patients compared to the natural disease history for adjacent compression fractures. This is strong evidence that interventional treatments for these fractures do not increase the risk of adjacent fractures.

Diagnostic efficacy and clinical impact of image-guided core needle biopsy of suspected vertebral osteomyelitis.

OBJECTIVES: The diagnostic yield and clinical impact of image-guided core needle biopsy (ICNB) of suspected vertebral osteomyelitis in adults is heterogenous in published studies owing to small sample sizes, indicating the need for large cohort studies. METHODS: A retrospective analysis of ICNBs was performed from 2010 to 2021 for patients with imaging findings consistent with vertebral osteomyelitis. For each biopsy, a series of factors were analyzed, as well as if histopathology was diagnostic of osteomyelitis and if microbiological cultures were positive. In addition, it was recorded in what way biopsy influenced clinical management regarding antimicrobial treatment. A multivariate statistical analysis was performed to evaluate the factors associated with yield. RESULTS: A total of 570 biopsies performed on 527 patients were included. A histopathologic diagnosis of osteomyelitis was made in 68.4% (359 of 525) of biopsies, and microbiological cultures were positive in 29.6% (169 of 570). Elevated erythrocyte sedimentation rate was positively associated with a histopathologic diagnosis of osteomyelitis (odds ratio [OR] =1.96, P = 0.007) and positive cultures from bone cores (OR = 1.02, P ≤0.001) and aspirate (OR = 1.02, P ≤0.001). Increased total core length was positively associated with a histopathologic diagnosis of osteomyelitis (OR = 1.81, P = 0.013) and positive cultures from bone cores (OR = 1.65, P = 0.049). Clinical management was affected by ICNB in 37.5% (214 of 570) of cases. CONCLUSIONS: In this large cohort, ICNB yielded approximately 30% positive cultures and changed clinical management in over one-third of the patients.

Diagnostic efficacy of image-guided core needle biopsy of suspected malignant osseous lesions: a retrospective cohort study from a single academic institution.

OBJECTIVES: To evaluate diagnostic yield and accuracy of image-guided core needle biopsy (ICNB) of suspected malignant osseous lesions in a large cohort of adults, evaluate what factors influence these measures, and offer technical recommendations to optimize yield. METHODS: A retrospective analysis of 2321 ICNBs performed from 2010 to 2021 was completed. The diagnostic yield and accuracy of the biopsies as well as a series of patient, lesion-related, and technical factors were retrospectively analyzed. Multivariate statistical analysis was performed to evaluate what factors were associated with yield and accuracy. Different cutoff values of total core length and core number were then tested to determine threshold values in relation to increased diagnostic yield. RESULTS: Diagnostic yield was 98.2% (2279/2321) and accuracy was 97.6% (120/123). Increased total core length (odds ratio [OR] = 2.34, 95% confidence interval [CI] (1.41-3.90), p = 0.001), core number (OR = 1.51, 95% CI (1.06-2.16), p = 0.02) and presence of primary malignancy (OR = 2.81, 95% CI (1.40-5.62), p = 0.004) were associated with improved yield. Lesion location in an extremity (OR = 0.27, 95% CI (0.11-0.68), p = 0.006) and using fluoroscopic imaging guidance (OR = 0.33, 95% CI (0.12-0.90), p = 0.03) were associated with lower yield. Cutoff thresholds in relation to increased diagnostic yield were found to be 20 mm total core length (marginal OR = 4.16, 95% CI = (2.09-9.03), p < 0.001), and three total cores obtained (marginal OR = 2.78, 95% CI (1.34-6.54), p = 0.005). None of the analyzed factors influenced diagnostic accuracy. CONCLUSIONS: ICNB has a high rate of diagnostic yield and accuracy. Several factors influence diagnostic yield; 20 mm core length and three total cores optimize yield. CLINICAL RELEVANCE STATEMENT: Image-guided core needle biopsy of suspected malignant osseous lesions is a safe procedure with a very high rate of diagnostic yield and accuracy. Obtaining 20 mm total core length and three total cores optimizes diagnostic yield. KEY POINTS: • In a retrospective cohort study, image-guided core needle biopsy of suspected osseous malignant lesions in adults was found to have very high rates of diagnostic yield and accuracy. • Increased total core length and core number of biopsies were each associated with increased diagnostic yield, and these relationships reached thresholds at 20 mm total core length and three total cores obtained. • The presence of a known primary malignancy was also associated with increased yield while using fluoroscopic imaging guidance and lesion location in an extremity were associated with decreased yield.

Essentials of Spinal Tumor Ablation.

Recent advances in percutaneous minimally invasive thermal ablation and vertebral augmentation provide radiologists with important arsenal for treatment of selected patients with spinal metastases. These interventions have proven to be safe, effective, and durable in treatment of selected patients with vertebral metastases. Attention to procedure techniques, including choice of ablation modality, vertebral augmentation technique, and thermal protection, is essential for improved patient outcomes. A detailed knowledge of such interventions and implementation of procedural safety measures will further heighten radiologists' role in the management of patients with spinal metastases.

Beyond Average: α-Particle Distribution and Dose Heterogeneity in Bone Metastatic Prostate Cancer.

α-particle emitters are emerging as a potent modality for disseminated cancer therapy because of their high linear energy transfer and localized absorbed dose profile. Despite great interest and pharmaceutical development, there is scant information on the distribution of these agents at the scale of the α-particle pathlength. We sought to determine the distribution of clinically approved [223Ra]RaCl2 in bone metastatic castration-resistant prostate cancer at this resolution, for the first time to our knowledge, to inform activity distribution and dose at the near-cell scale. Methods: Biopsy specimens and blood were collected from 7 patients 24 h after administration. 223Ra activity in each sample was recorded, and the microstructure of biopsy specimens was analyzed by micro-CT. Quantitative autoradiography and histopathology were segmented and registered with an automated procedure. Activity distributions by tissue compartment and dosimetry calculations based on the MIRD formalism were performed. Results: We revealed the activity distribution differences across and within patient samples at the macro- and microscopic scales. Microdistribution analysis confirmed localized high-activity regions in a background of low-activity tissue. We evaluated heterogeneous α-particle emission distribution concentrated at bone-tissue interfaces and calculated spatially nonuniform absorbed-dose profiles. Conclusion: Primary patient data of radiopharmaceutical therapy distribution at the small scale revealed that 223Ra uptake is nonuniform. Dose estimates present both opportunities and challenges to enhance patient outcomes and are a first step toward personalized treatment approaches and improved understanding of α-particle radiopharmaceutical therapies.

Benign Bone Tumors Beyond Osteoid Osteoma: Percutaneous Minimally Invasive Image-Guided Interventions.

Painful benign bone tumors often adversely influence quality of life primarily due to skeletal-related events such as unremittable pain, pathologic fracture, neurologic deficit, as well as skeletal growth disturbance. Substantial advances in percutaneous minimally invasive interventions for treatment of painful benign bone tumors beyond osteoid osteoma have been established as safe, efficacious, and durable treatments to achieve definitive cure. This article details the available armamentarium and most recent advances in minimally invasive percutaneous interventions and the role of radiologists for the management of patients with benign bone tumors beyond osteoid osteoma.

Percutaneous Treatment of Spinal Metastases.

Percutaneous image-guided minimally invasive thermal ablation and vertebral augmentation are robust techniques, part of the available armamentarium used by radiologists for the management of patients with spinal metastases. Such interventions have been established to be safe and effective in treatment of selected patients with vertebral metastases. Special attention to procedure techniques including choice of ablation modality, vertebral augmentation technique, and thermal protection is essential for improved patient outcomes.

Spine metastases: thermal ablation and augmentation.

Substantial advances in percutaneous minimally invasive musculoskeletal oncologic interventions including thermal ablation and vertebral augmentation offer a robust armamentarium for interventional radiologists for management of patients with spinal metastases. Such interventions have proved safe and effective in management of selected patients with vertebral metastases. Special attention to procedure techniques including choice of ablation modality, vertebral augmentation technique, and thermal protection is essential for improved patient outcomes. Familiarity with the described interventions and implementation of procedural safety measures will further enhance the role of radiologists in the management of patients with spinal metastases. This article provides a review of the most recent advances in thermal ablation and vertebral augmentation as well as the role of radiologists for treatment of spinal metastases.

ACR Appropriateness Criteria® Management of Vertebral Compression Fractures: 2022 Update.

Vertebral compression fractures (VCFs) can have a variety of etiologies, including trauma, osteoporosis, or neoplastic infiltration. Osteoporosis related fractures are the most common cause of VCFs and have a high prevalence among all postmenopausal women with increasing incidence in similarly aged men. Trauma is the most common etiology in those >50 years of age. However, many cancers, such as breast, prostate, thyroid, and lung, have a propensity to metastasize to bone, which can lead to malignant VCFs. Indeed, the spine is third most common site of metastases after lung and liver. In addition, primary tumors of bone and lymphoproliferative diseases such as lymphoma and multiple myeloma can be the cause of malignant VCFs. Although patient clinical history could help raising suspicion for a particular disorder, the characterization of VCFs is usually referred to diagnostic imaging. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Intraosseous hibernoma: clinicopathologic and imaging analysis of 18 cases.

AIMS: Intraosseous hibernomas are rarely reported tumours with brown adipocytic differentiation of unknown aetiology, with only 38 cases documented in the literature. We sought to further characterise the clinicopathologic, imaging and molecular features of these tumours. METHODS AND RESULT: Eighteen cases were identified occurring in eight females and 10 males (median age = 65 years, range = 7-75). Imaging indication was cancer surveillance/staging in 11 patients and clinical concern for a metastasis was raised in 13 patients. The innominate bone (7), sacrum (5), mobile spine (4), humerus (1) and femur (1) were involved. Median tumour size was 1.5 cm (range = 0.8-3.8). Tumours were sclerotic (11), mixed sclerotic and lytic (4) or occult (1). Microscopically, tumours were composed of large polygonal cells with distinct cell membranes, finely vacuolated cytoplasm, central or paracentral small bland nuclei with prominent scalloping. Growth around trabecular bone was observed. Tumour cells were immunoreactive for S100 protein (15/15) and adipophilin (5/5), while negative for keratin AE1/AE3(/PCK26) (0/14) and brachyury (0/2). Chromosomal microarray analysis, performed on four cases, did not show clinically significant copy number variation across the genome or on 11q, the site of AIP and MEN1. CONCLUSION: Analysis of 18 cases of intraosseous hibernoma, to our knowledge, the largest series to date, revealed that these tumours are most often detected in the spine and pelvis of older adults. Tumours were generally small, sclerotic and frequently found incidentally and can raise concern for metastasis. Whether or not these tumours are related to soft tissue hibernomas is uncertain.

Benign Bone Tumors: State of the Art in Minimally Invasive Percutaneous Interventions.

Painful benign bone tumors most commonly affect pediatric patients and young adults. They may be associated with skeletal-related events such as intractable pain, pathologic fracture, neurologic deficit as a consequence of nerve or spinal cord compression, as well as growth disturbance. Consequently, they often result in diminished activity and adversely affect quality of life. There have been substantial recent advances in percutaneous minimally invasive image-guided interventions for treatment of painful benign bone tumors including thermal ablation (radiofrequency ablation, cryoablation, microwave ablation, laser photocoagulation, and high-intensity focused US ablation), chemical (alcohol) ablation, cementoplasty, and intralesional injections. The safety, efficacy, and durability of such interventions have been established in the recent literature and as such, the role of musculoskeletal interventional radiologists in the care of patients with benign bone lesions has substantially expanded. The treatment goal of minimally invasive musculoskeletal interventions in patients with benign bone tumors is to achieve definitive cure. The authors detail the most recent advances and available armamentarium in minimally invasive image-guided percutaneous interventions with curative intent for the management of benign bone tumors. © RSNA, 2022.

Comprehensive Palliative Musculoskeletal Interventional Radiology Care for Patients with Cancer.

Substantial advances in percutaneous image-guided minimally invasive musculoskeletal oncologic interventions offer a robust armamentarium for interventional radiologists for management of cancer. The authors outline the most recent advances in such interventions and the role of interventional radiologists in managing cancer in modern-era practice. Percutaneous minimally invasive musculoskeletal interventions including thermal ablation, cementation with or without osseous reinforcement by implants, osteosynthesis, neurolysis, and embolization, as well as palliative injections, have been successfully used by interventional radiologists to achieve durable, timely, safe, effective palliation in a multidisciplinary setting and have been progressively incorporated into the management paradigm for patients with cancer with musculoskeletal involvement. Familiarity with the described interventions and implementation of procedural safety measures, combined with integration of these procedures into clinical practice with the support of the National Comprehensive Cancer Network and the American College of Radiology, as well as continued technologic advances in procedural equipment design, will further enhance the role of interventional radiologists in cancer management. ©RSNA, 2022.

Interventional Palliation of Painful Extraspinal Musculoskeletal Metastases.

The musculoskeletal system is commonly involved by metastases, and skeletal-related events such as intractable pain due to direct osseous tumor involvement, pathologic fracture, and neurologic deficits as a result of nerve compression often adversely affect patient's quality of life. There have been substantial advances in percutaneous minimally invasive musculoskeletal oncologic interventions for the management of patients with musculoskeletal metastases including thermal ablations, cementation with or without osseous reinforcement via implants, osteosynthesis, neurolysis, and palliative injections which are progressively incorporated in clinical practice. These interventions are performed, in conjunction with or supplemented by adjuvant radiation therapy, systemic therapy, surgery, or analgesics, to achieve durable pain palliation, local tumor control, or cure. This article reviews minimally invasive percutaneous image-guided musculoskeletal oncologic interventions for the management of patients with extraspinal musculoskeletal metastases.