Use of preoperative vascular embolisation in spinal metastasis resection

Comparison of intraoperative blood loss and perioperative complications between preoperative embolization and nonembolization combined with spinal tumor surgeries: a systematic review and meta-analysis

PURPOSE

The present study aimed to comparatively evaluate intraoperative blood loss (IBL) and perioperative complications between preoperative embolization (PE) and nonembolization (NE) combined with spinal tumor surgeries as well as to determine the subgroup of spinal tumor surgeries suitable for PE.

METHODS

A systematic search in PubMed and EMBASE and an additional search by reference lists of the retrieved studies were undertaken by two reviewers. The mean IBL and perioperative complication rate were employed as the effect size in the general quantitative synthesis through direct calculation. Meta-analysis was performed using standardized mean difference (SMD) and weighted mean difference (WMD) of IBL and the odds ratio (OR) of complications. Heterogeneity was assessed using the I2 statistic.

RESULTS

The reviewers selected 17 published studies for the general quantitative synthesis and meta-analyses. The mean IBL of spinal tumor surgeries was 1786.3 mL in the NE group and 1716.4 mL in the PE group. The mean IBL between the two groups was similar. The pooled WMD and SMD of IBL in spinal tumor surgeries was 324.15 mL (95% CI 89.50-1640.9, p = 0.007) and 0.398 (95% CI 0.114-0.682, p = 0.006), respectively. The reduction of the PE group compared with the NE group for the rates of major complications and major hemorrhagic complications were 7.80% and 5.71%, respectively. The risk of PE-related complications in the PE group was only 1.53% more than in the PE group. The pooled OR of major complications in spinal tumor surgeries was 1.426 (95% CI 0.760-2.674; p = 0.269).

CONCLUSIONS

PE may be suitable for spinal tumor surgeries and some subgroups. From the perspective of complications, PE may also be a feasible option for spinal tumor surgeries.

Direct intralesional n-butyl-cyanoacrylate embolization for intractable vertebral hemangioma bleeding: a salvage technique. Illustrative case

BACKGROUND

Surgical resection of vertebral hemangiomas in the setting of cord compression can be technically difficult and has the potential for life-threatening hemorrhage. The authors report a case of intraoperative direct intralesional n-butyl-cyanoacrylate embolization for intractable vertebral hemangioma bleeding.

OBSERVATIONS

A 53-year-old woman presented for repeat surgery of a residual vertebral hemangioma after a previous debulking, laminectomy, and fixation that were without problems with bleeding. The second surgery was complicated by intractable hemorrhage. Bleeding was controlled with direct intralesional n-butyl-cyanoacrylate embolization after fluoroscopy without accompanying endovascular embolization.

LESSONS

Aggressive vertebral hemangiomas should ideally be managed in centers where transarterial embolization is available. If such centers are not available or there is still intractable intraoperative bleeding despite preoperative embolization, direct intralesional embolization may be considered as a potential salvage technique.

Does the anatomical region predict blood loss or neurological deficits in embolized renal cancer spine metastases? A single-center experience with 31 patients

Background

No comparison of a single hypervascular tumor entity in terms of major complications in different spinal regions has been performed. We aimed to evaluate post-embolic and post-operative outcomes in anatomic regions with renal cell carcinoma (RCC) metastases to the spine.

Methods

We retrospectively evaluated data from patients with confirmed, embolized, and surgically treated RCC spine metastases at a single-spine center between 2010 and 2020. Patients were divided into thoracic (TSM) and lumbar (LSM) spine metastasis groups.

Results

Seventeen patients had TSM and 14 had LSM. In all cases, embolization was performed preoperatively. The ΔHb value did not differ between the two groups pre- and postoperatively (p=0.3934). There was no significant difference in intraoperative blood loss between both groups either within 1 day or 2 days after embolization. Neurological deficits occurred in eight patients after embolization or surgery, with no significant difference between TSM (n=5) and LSM (n=3).

Conclusions

Embolization is the standard procedure for the preoperative treatment of hypervascular spinal metastases, possible up to 48 h before surgery, without the risk of higher intraoperative blood loss. Regardless of intraoperative complications, major complications can occur up to several hours after embolization. We recommend surgery the day after embolization to reliably detect neurologic complications from this procedure.

Effectiveness of Preoperative Embolization in Patients with Spinal Metastases: A Systematic Review and Meta-Analysis

OBJECTIVE

Debate on the effectiveness of preoperative embolization for spinal metastatic lesions, especially for nonhypervascular tumors, has persisted. The present study aimed to identify the effectiveness of preoperative embolization in patients who had undergone surgery for spinal metastasis.

METHODS

Two of us (Z.T. and Z.H.) independently searched the PubMed, Embase, and Cochrane Central Register of Controlled Trials databases to identify eligible clinical studies that had compared the outcomes of patients treated surgically for spinal metastatic disease with or without preoperative embolization. The primary outcomes included intraoperative blood loss, perioperative blood loss, and transfusion requirements. The secondary outcomes include the operative time, overall survival, and complication rates. Meta-analyses were performed for subgroups of hypervascular, nonhypervascular, and mixed tumors. A fixed effects model was applied when I² was <50%, and a random effects model was applied when I² was >50%.

RESULTS

A total of 12 studies (1 randomized controlled trial and 11 retrospective case-control studies), with 744 patients, were included. Significantly less intraoperative blood loss (mean difference [MD], -1171.49 mL; 95% confidence interval [CI], -2283.10 to -59.88; P = 0.039), fewer blood transfusions (MD, -3.13 U; 95% CI, -4.86 to -1.39; P < 0.001), and shorter operative times (MD, -33.91 minutes; 95% CI, -59.65 to -8.17; P = 0.010) were identified for the embolization group in the hypervascular subgroup. In the nonhypervascular and mixed tumor subgroups, no differences in effectiveness were identified in blood loss, transfusion requirement, or operative time when stratified by the use of embolization. The overall survival and complication rates were similar between the embolization and nonembolization groups in each subgroup.

CONCLUSIONS

The current data support the use of preoperative embolization for hypervascular metastatic tumors to the spine. However, little evidence is available to support the use of preoperative embolization for nonhypervascular metastatic tumors to the spine.

Only Tumors Angiographically Identified as Hypervascular Exhibit Lower Intraoperative Blood Loss Upon Selective Preoperative Embolization of Spinal Metastases: Systematic Review and Meta-Analysis

Background

The role of preoperative embolization (PE) in reducing intraoperative blood loss (IBL) during surgical treatment of spinal metastases remains controversial.

Methods

A systematic search was conducted for retrospective studies and randomized controlled trials (RCTs) comparing the IBL between an embolization group (EG) and non-embolization group (NEG) for spinal metastases. IBL data of both groups were synthesized and analyzed for all tumor types, hypervascular tumor types, and non-hypervascular tumor types.

Results

In total, 839 patients in 11 studies (one RCT and 10 retrospective studies) were included in the analysis. For all tumor types, the average IBL did not differ significantly between the EG and NEG in the RCT (P = 0.270), and there was no significant difference between the two groups in the retrospective studies (P = 0.05, standardized mean difference [SMD] = −0.51, 95% confidence interval [CI]: −1.03 to 0.00). For hypervascular tumors determined as such by consensus (n = 542), there was no significant difference between the two groups (P = 0.52, SMD = −0.25, 95% CI: −1.01 to 0.52). For those determined as such using angiographic evidence, the IBL was significantly lower in the EG than in the NEG group, in the RCT (P = 0.041) and in the retrospective studies (P = 0.004, SMD = −0.93, 95% CI: −1.55 to −.30). For IBL of non-hypervascular tumor types, both the retrospective study (P = 0.215) and RCT (P = 0.947) demonstrated no statistically significant differences in IBL between the groups.

Conclusions

Only tumors angiographically identified as hypervascular exhibited lower IBL upon PE in this study. Further exploration of non-invasive methods to identify the vascularity of tumors is warranted.

Neurologic Complications of Preoperative Embolization of Spinal Metastasis: A Systemic Review of the Literature Identifying Distinct Mechanisms of Injury

BACKGROUND

Preoperative embolization of spinal metastases may improve outcomes of resection by reducing surgical blood loss and operative time. Neurologic complications are rarely reported and the mechanisms leading to injury are poorly described.

METHODS

We present 2 illustrative cases of embolization-related neurologic injury from distinct mechanisms and the findings of a systemic literature review of similar complications according to the PRISMA guidelines.

RESULTS

A 77-year-old man with a history of renal cell carcinoma presented with gait dyscoordination and arm pain/weakness. Magnetic resonance imaging showed a C7/T1 mass causing severe compression of the C7/T1 roots and spinal cord. After embolization and tumor resection/fusion, lethargy prompted imaging showing multiple posterior circulation infarcts believed to be secondary to reflux of embolic particles. A 75-year-old man with renal cell carcinoma presented with L1 level metastasis causing conus compression and experienced paraplegia after superselective particle embolization presumed to be secondary to flow disruption of the artery of Adamkiewicz. Analysis of the literature yielded 6 articles reporting instances of cranial infarction/ischemia occurring in 10 patients, 12 articles reporting spinal cord ischemia/infarction occurring in 17 patients, and 5 articles reporting symptomatic postembolization tumoral swelling in 5 patients.

CONCLUSIONS

Neurologic injury is a risk of preoperative embolization of spinal metastasis from either compromise of spinal cord vascular supply or cranial stroke from reflux of embolic particles. Postprocedural tumor swelling rarely leads to clinical deficit. Awareness of these complications and the presumed mechanisms of injury may aid clinicians in implementing interventions and in counseling patients before treatment.

Surgical Therapy of Vertebral Metastases. Are there Predictive Parameters for Intraoperative Excessive Blood Loss despite Preoperative Embolization?

Aims and background

Preoperative embolization of vertebral metastases has been shown to lower intraoperative blood loss. Nevertheless, excessive up to life-threatening blood loss can occur despite embolization. We therefore decided to evaluate possible parameters for predicting significant blood loss in a surgically homogeneous group of patients with vertebral metastases.

Methods

Patients with vertebral metastases of the thoracic and thoracolumbar spine who underwent preoperative embolization were included. All patients had existing or impending neurological deficit as the main indication for direct metastasis reduction. The parameters evaluated were the technical feasibility of embolization, vascularization grade of metastasis, success of embolization, tumor type in relation to blood loss, and interval between embolization and surgery.

Results

Twenty-seven patients fullfilled the inclusion criteria. Technically complete embolization was feasible in 14 patients (52%) and fully successful embolization was obtained in 10 patients (37%). Eighty-three percent of the renal cell carcinomas were hypervascularized, but also 67% of the breast carcinoma patients had hypervascularized tumors. No permanent complications occurred during embolization, but two patients had pain and another two experienced a transient burning sensation. A significant difference in intraoperative blood loss was only found between patients achieving partially or fully successful embolization in the subgroup of hypervascularized grade III metastases.

Conclusions

The success of embolization in the group of hypervascularized grade III metastases was the only predictor for the extent of blood loss in our study. Due to the inaccuracy of predicting high blood loss in general all possible precautions for excessive blood loss should be taken despite preoperative embolization. Further randomized studies to determine the indications and results of embolization seem desirable. Free full text available at www.tumorionline.it

Preoperative Embolization and Complete Tumoral Resection of a Cervical Aggressive Epithelioid Osteoblastoma

BACKGROUND

Epithelioid "aggressive" osteoblastoma (EOB) is a rare and more aggressive subtype of osteoblastoma (OB) with a higher recurrence rate, greater risk of malignant transformation, larger size, and greater intraoperative blood loss. The present case report illustrates that preoperative angioembolization of an EOB can be safely performed with low intraoperative blood loss.

CASE DESCRIPTION

A 21-year-old male patient presented to our institution with a 4-month history of neck discomfort, radicular pain in the proximal right arm, and mild weakness of the right biceps and triceps muscles. Imaging was suggestive of EOB, and computed tomography-guided biopsy confirmed the diagnosis. The patient underwent same-day preoperative angioembolization of the major feeding vessels and subsequent complete tumor resection. During the procedure, he experienced minimal blood loss and did not require blood transfusion.

CONCLUSIONS

EOB is a highly vascular primary bony lesion. To minimize intraoperative blood loss, preoperative angioembolization should be considered in the treatment of cervical spine EOB.

Preoperative embolization in spinal tumour surgery: Enhancing its effectiveness

We conducted a retrospective review of 221 patients, who underwent spinal oncologic surgery at a tertiary university hospital between 2005 and 2014; in order to identify and validate factors that influence the impact of preoperative embolization of spinal tumours on outcome measures of blood loss and transfusion requirements in spinal oncologic surgery. We also focused on primary tumour type and type of spinal surgery performed. Patients' electronic and physical records were reviewed to provide demographic data, tumour characteristics, embolization techniques and surgical procedure details. These data were analysed against recorded outcome measures of blood loss (absolute volume and haemoglobin reduction) and transfusion requirements. Forty eight patients who received preoperative embolization were compared against 173 patients who did not. There was a tendency towards reduced blood loss and transfusion requirements in embolized spinal metastases from HCC and thyroid; as well as primary spine tumours, though the differences were not significant. Total embolization of arterial supply to spinal tumours resulted in significantly less blood loss as compared to partial or subtotal embolization. In addition, median blood loss was lower in patients receiving a more proximal embolization and in patients who underwent surgery between 13 and 24h post-embolization despite the insignificant difference. To conclude, preoperative spinal tumour embolization is likely to be effective in reducing blood loss if a total embolization is performed 13-24h prior to the surgery. Similarly, the impact of embolization is likely to be more profound in metastases from HCC, thyroid and primary spine tumours.

Unusual Metastasis of Papillary Thyroid Cancer to the Thoracic Spine: A Case Report, New Surgical Management Proposal, and Review of the Literature

Papillary thyroid carcinoma (PTC) is significantly more common than follicular thyroid carcinoma (FTC), yet FTC has a much higher tendency to metastasize to the spinal column. We present a rare case of a metastatic thoracic spinal column lesion originating from the PTC. Thyroid carcinoma is known to be highly vascular with a significant tendency to hemorrhage during surgical resection. This increased tendency to hemorrhage leads to unanticipated intraoperative risks when the type of cancer is not diagnosed before surgical resection. Complications related to intraoperative bleeding can be prevented by visualization using angiography and preoperative embolization. The type of cancer is ideally diagnosed before tumor resection either by the standard metastatic workup or histologically after the biopsy. However, limitations exist in these methods, therefore, hypervascular tumors such as metastatic thyroid cancer can go undiagnosed until after surgical resection. In addition to our case report, we present a review of the literature regarding diagnostic and treatment strategies for hypervascular thyroid tumors and propose a new algorithm for the surgical management of spinal tumors with an unknown origin for optimization of preoperative and perioperative care.

Modern Palliative Treatments for Metastatic Bone Disease: Awareness of Advantages, Disadvantages, and Guidance

BACKGROUND

Metastatic disease is the most common malignancy of the bone. Prostate, breast, lung, kidney, and thyroid cancer account for 80% of skeletal metastases. Bone metastases are associated with significant skeletal morbidity including severe bone pain, pathologic fractures, spinal cord or nerve roots compression, and malignant hypercalcemia. These events compromise greatly the quality of life of the patients. The treatment of cancer patients with bone metastases is mostly aimed at palliation.

OBJECTIVE

This article aims to present these palliative treatments for the patients with bone metastases, summarize the clinical applications, and review the techniques and results.

METHODS

It gives an extensive overview of the possibilities of palliation in patients with metastatic cancer to the bone.

RESULTS AND DISCUSSION

Currently, modern treatments are available for the palliative management of patients with metastatic bone disease. These include modern radiation therapy, chemotherapy, embolization, electrochemotherapy, radiofrequency ablation, and high-intensity focused ultrasound. As such it is of interest for all physicians with no experience with these developments to make palliative procedures safer and more reliable.

Benign Tumors of the Spine: Has New Chemotherapy and Interventional Radiology Changed the Treatment Paradigm?

STUDY DESIGN

Clinically based systematic review.

OBJECTIVE

To determine the role of (A) medical treatment and (B) interventional radiology as either adjuvant or stand-alone treatment in primary benign bone tumors of the spine.

METHODS

A multidisciplinary panel of spine surgeons, radiation oncologists, and medical oncologists elaborated specific focused questions regarding aneurysmal bone cyst, giant cell tumor, and osteoid osteoma. Denosumab, bisphosphonate, interferon, bone marrow aspirate, doxycycline, thermal ablation, and selective arterial embolization were identified as areas of interest for the article. A systematic review was performed through MEDLINE and EMBASE. Recommendations based on the literature review and clinical expertise were issued using the GRADE system.

RESULTS

The overall quality of the literature is very low with few multicenter prospective studies. For giant cell tumor, combination with Denosumab identified 14 pertinent articles with four multicenter prospective studies. Nine studies were found on bisphosphonates and six for selective arterial embolization. The search on aneurysmal bone cyst and selective arterial embolization revealed 12 articles. Combination with Denosumab, Doxycycline, and bone marrow aspirate identified four, two, and three relevant articles respectively. Eleven focused articles were selected on the role of thermal ablation in osteoid osteoma.

CONCLUSION

Alternative and adjuvant therapy for primary benign bone tumors have emerged. Their ability to complement or replace surgery is now being scrutinized and they may impact significantly the algorithm of treatment of these tumors. Most of the data are still emerging and further research is desirable. Close collaboration between the different specialists managing these pathologies is crucial.

LEVEL OF EVIDENCE

N/A.

Preoperative embolization of primary bone tumors: A case control study

AIM: To study the safety and effectiveness of preoperative embolization of primary bone tumors in relation to intraoperative blood loss, intraoperative blood transfusion volume and surgical time.

METHODS: Thirty-three patients underwent preoperative embolization of primary tumors of extremities, hip or vertebrae before resection and stabilization. The primary osseous tumors included giant cell tumors, aneurysmal bone cyst, osteoblastoma, chondroblastoma and chondrosarcoma. Twenty-six patients were included for the statistical analysis (embolization group) as they were operated within 0-48 h within preoperative embolization. A control group (non-embolization group, n = 28) with bone tumor having similar histological diagnosis and operated without embolization was retrieved from hospital record for statistical comparison.

RESULTS: The mean intraoperative blood loss was 1300 mL (250-2900 mL), the mean intraoperative blood transfusion was 700 mL (0-1400 mL) and the mean surgical time was 221 ± 76.7 min for embolization group (group I, n = 26). Non-embolization group (group II, n = 28), the mean intraoperative blood loss was 1800 mL (800-6000 mL), the mean intraoperative blood transfusion was 1400 mL (700-8400 mL) and the mean surgical time was 250 ± 69.7 min. On comparison, statistically significant (P < 0.001) difference was found between embolisation group and non-embolisation group for the amount of blood loss and requirement of blood transfusion. There was no statistical difference between the two groups for the surgical time. No patients developed any angiography or embolization related complications.

CONCLUSION: Preoperative embolization of bone tumors is a safe and effective adjunct to the surgical management of primary bone tumors that leads to reduction in intraoperative blood loss and blood transfusion volume.

[Operative therapy of spinal metastases from urological tumors]

The treatment of bone metastases from urological tumors represents a palliative form of therapy, apart from the resection of solitary metastases from renal cell carcinomas. Due to the high incidence of spinal metastases this can result in clinically significant symptoms and possible complications for patients, such as pain, spinal instability and compression of the spinal canal with corresponding neurological deficits. By the use of targeted diagnostics and induction of radiotherapeutic and/or surgical treatment, for the majority of patients an immediate reduction in pain as well as early mobilization and sometimes even regression of existing neurological deficits and therefore an improved quality of life can be achieved.

Current treatment modalities for spinal metastases secondary to thyroid carcinoma

BACKGROUND

The spine is the most common site of bone metastases due to thyroid cancer, which develop in more than 3% of patients with well-differentiated thyroid cancer. Nearly half of patients with bone metastases from thyroid cancer develop vertebral metastases. Spinal metastases are associated with significantly reduced quality of life due to pain, neurological deficit, and increased mortality.

SUMMARY

Treatment options for patients with thyroid spinal metastases include radioiodine therapy, pharmacologic therapy, and surgical treatments, with recent advances in radiosurgery and minimally invasive spinal surgery as well. Therapeutic interventions require a multidisciplinary approach and aim to control pain, preserve or improve neurologic function, optimize local tumor control, and improve quality of life. We have proposed a three-tiered approach to the management and practical algorithms for patients with spinal metastases from thyroid carcinoma.

CONCLUSIONS

The introduction of novel and improved techniques for the treatment of spinal metastases has created the opportunity to significantly improve control of metastatic tumor growth and the quality of life for the patients with spinal metastases from thyroid cancer. In order for these options to be effectively used, a multidisciplinary approach must be applied in the management of the patients with thyroid spinal metastases.

Optimal schedule of preoperative embolization for spinal metastasis surgery

STUDY DESIGN

A retrospective study.

OBJECTIVE

To investigate the relationship between intraoperative blood loss during spinal metastasis surgery and the surgical delay after preoperative embolization.

SUMMARY OF BACKGROUND DATA

Delaying surgery after embolization is thought to diminish its effectiveness because of revascularization, but there has been no scientific study that supports this hypothesis.

METHODS

We reviewed data from 66 consecutive posterior palliative decompression surgical procedures for spinal metastasis from thyroid and renal cell carcinoma (39 thyroid and 27 renal) in 58 patients between 2004 and 2012. All patients underwent preoperative angiography. The timing of preoperative embolization was determined on the basis of the operating room and interventional radiologist schedules. Excluding one case who did not receive embolization due to lack of hypervascularity, we analyzed 65 cases to compare intraoperative blood loss according to the completeness of embolization and the time lapse between embolization and surgery.

RESULTS

Surgical procedures were performed on the same day of embolization in 21 cases (same day-group), and on the next day after embolization in 39 cases (next-day group). Five surgical procedures were performed 2 days later. The intraoperative blood loss was significantly lesser with complete embolization than with partial embolization (mean ± standard deviation: 809 ± 835 vs. 1210 ± 904 mL, P = 0.03). Among those with complete embolization, the intraoperative blood loss as well as the perioperative transfusion requirement was significantly lesser in the same-day group than in the next-day group (mean ± standard deviation: blood loss: 433 ± 376 vs. 1012 ± 974 mL, P = 0.01; transfusion requirement: 1.5 ± 1.7 vs. 4.2 ± 4.1 units, P = 0.04).

CONCLUSION

Preoperative embolization showed greater effectiveness in reducing intraoperative blood loss when surgery for spinal metastasis was performed on the same day than when surgery was delayed. Surgery should be performed on the same day of embolization if possible.

LEVEL OF EVIDENCE

4.

Clinical characteristics and treatment options for two types of osteoblastoma in the mobile spine: a retrospective study of 32 cases and outcomes

PURPOSE

A retrospective study of 32 patients with osteoblastoma (OBL) in the mobile spine was performed to analyze the clinical characteristics of two types of spinal OBL. We also aimed to find influential factors for OBL in the mobile spine.

METHODS

Between 2002 and 2011, 32 patients with either conventional osteoblastoma (CO) or aggressive osteoblastoma (AO) in the mobile spine were treated in our center. All patients were treated with either total excision or subtotal excision + postoperative radiotherapy. The mean follow-up was 45.8 (18-128) months. Clinical data and surgery efficacy were analyzed to search for clinical characteristics of two subtypes of spinal OBL and discuss the possible factors influencing relapse.

RESULTS

There is significant difference between CO and AO in tumor size (p < 0.0005), preoperative alkaline phosphatase (ALP, p < 0.0005) and intraoperative blood loss (p = 0.013). Multivariate logistic regression was used to find the influential factors for relapse and the results were: preoperative ALP, b = 0.023, p = 0.029; surgery protocol, b = -7.597, p = 0.007; tumor size, ≥3/<3, b = 24.805, p < 0.0005; age, b = 0.054, p = 0.632; and pathology type, b = 1.998, p = 0.34.

CONCLUSIONS

Tumor size, preoperative ALP and CT images were helpful for distinguishing AO from CO. The difference in intraoperative blood loss between CO and AO is mainly attributed to the size of the lesion. Preoperative ALP, surgery protocol and tumor size (≥3/<3) were considered to significantly influence relapse of spinal OBL.

Preoperative embolization of spinal tumors: variables affecting intraoperative blood loss after embolization

BACKGROUND

Preoperative embolization of spinal tumors is often used to reduce blood loss from surgery. Intraoperative blood loss, even in patients who undergo embolization, is potentially multifactorial; embolization techniques, surgical procedures or tumor characteristics may affect intraoperative blood loss.

PURPOSE

To retrospectively analyze factors affecting intraoperative blood loss in patients who had undergone spinal tumor embolization; and to assess the safety of the procedure.

MATERIAL AND METHODS

Sixty-two patients (median age, 60 years) with a tumor involving the thoracic (n = 42) or lumbar (n = 20) spine underwent preoperative tumor embolization with particles. Multiple variables, including patient characteristics, tumor characteristics, embolization techniques, and surgical procedures, were evaluated with respect to intraoperative blood loss and transfusion requirement. Complications related to the embolization procedures were also recorded. Univariate and multivariate analysis were performed to analyze the variables affecting the intraoperative blood loss and transfusion requirement.

RESULTS

Complete or near-complete tumor embolization was achieved in 47 patients. The average estimated blood loss (EBL) and packed red blood cells units transfused during surgery were 2554 mL (range, 250-11,000 mL) and 7 units (range, 0-28 units), respectively. Univariate analysis indicated tumor volume, surgical approach, and invasiveness of the spinal surgery to be significant variables affecting EBL. Tumor histology and extent, tumor vascularity, degree of embolization, and size of embolic particle did not affect operative blood loss. On multivariate analysis, invasiveness of the surgery was the only variable that influenced EBL. Two patients developed irreversible neurologic deficits following embolization.

CONCLUSION

Embolization technique or completeness has a limited effect on operative blood loss after preoperative spinal tumor embolization. Operative blood loss from spinal surgery is dependent primarily on the invasiveness of the surgery. Although preoperative embolization is a relatively safe procedure, there remains a risk of cord ischemia.

Is preoperative embolization a prerequisite for spinal metastases surgical management?

BACKGROUND

Preoperative embolization decreases the intraoperative risk of hemorrhage in spinal decompression surgery of hypervascular metastases such as renal cell carcinoma. There is no consensus concerning embolization in other metastases. The purpose of this study was to compare the intraoperative amount of blood loss in embolized versus non-embolized patients, seeking for differences depending on the primary tumor and the extent of surgery.

PATIENTS AND METHODS

Ninety-three patients, average age 60.5 years, were operated. The origins of metastases were: 28 breast cancer (30.1%), 19 pulmonary carcinoma (20.4%), 16 renal cell carcinoma (17.2%), 30 other cancers (32.3%). Surgical procedures were: 52 thoracolumbar laminectomies with instrumentation, 29 thoracolumbar corpectomies or vertebrectomies, 12 cervical corpectomies. A preoperative microsphere embolization was performed in 35 patients. Blood loss was evaluated by: blood volume in surgical aspiration devices, number of transfused packed red blood cells units and hemoglobin variation during surgery.

RESULTS

Renal metastases were systematically embolized. In the breast group, there was no significant difference (P>0.05) in blood loss between embolization versus non-embolization. In the pulmonary group and in other metastases, no difference was found either. The extent of surgery (corpectomy/vertebrectomy versus thoracolumbar instrumentation and cervical corpectomy) increased bleeding: breast 1775ml versus 778ml and 600ml respectively (P=0.048), pulmonary 2500ml versus 430ml and 180ml (P=0.020), renal 3346ml versus 1175ml and 780ml (P=0.036) and others 1550ml versus 474ml and 400ml (P=0.020).

CONCLUSIONS

Embolization decreases the risk of hemorrhage in highly vascularized metastases such as renal cell carcinoma. A benefit of embolization was not found for metastases of breast or pulmonary tumors. As far as other metastases, thyroid carcinoma should be analyzed on a greater cohort. The extent of surgery remains an important risk factor for intraoperative bleeding. A preoperative angiogram should be carried out in all types of metastases prior to a thoracolumbar corpectomy or vertebrectomy to perform an embolization if the tumor is hypervascular.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Preoperative embolization significantly decreases intraoperative blood loss during palliative surgery for spinal metastasis

Several studies have evaluated the efficacy of preoperative embolization in devascularizing tumors. However, no study has measured intraoperative blood loss in a single palliative surgery compared with a control group without preoperative embolization. The purpose of this retrospective study was to evaluate the efficacy of preoperative embolization on intraoperative blood loss in palliative decompression and instrumented surgery using a posterior approach for spinal metastasis. Between 2000 and 2010, forty-six patients underwent palliative decompression and instrumented surgery using a posterior approach for spinal metastasis in the thoracic and lumbar spine. Preoperative embolization was performed in 23 patients (embolization group), and surgery was performed within 3 days after embolization. The embolic materials used were polyvinyl alcohol particles, gelatin sponge, and metallic coils. Twenty-three patients did not undergo embolization (no embolization group). Pain and neurologic symptoms in all 46 patients were relieved postoperatively. Average intraoperative blood loss was 520 mL (range, 140-1380 mL) in the embolization group and 1128 mL (range, 100-3260 mL) in the no embolization group (P<.05). In the embolization group, intraoperative blood loss was not correlated with the degree of tumor vascularization, completeness of embolization, or time between embolization and surgery. Intraoperative blood loss after preoperative embolization was less than half that after no preoperative embolization.

Management of metastatic sacral tumours

PURPOSE

Metastatic involvement of the sacrum is rare and there is a paucity of studies which deal with the management of these tumours since most papers refer to primary sacral tumours. This study aims to review the available literature in the management of sacral metastatic tumours as reflected in the current literature.

METHODS

A systematic review of the English language literature was undertaken for relevant articles published over the last 11 years (1999-2010). The PubMed electronic database and reference lists of key articles were searched to identify relevant studies using the terms "sacral metastases" and "metastatic sacral tumours". Studies involving primary sacral tumours only were excluded. For the assessment of the level of evidence quality, the CEBM (Oxford Centre of Evidence Based Medicine) grading system was utilised.

RESULTS

The initial search revealed 479 articles. After screening, 16 articles identified meeting our inclusion criteria [1 prospective cohort study on radiosurgery (level II); 2 case series (level III); 4 retrospective case series (level IV) and 9 case reports (level IV)].

CONCLUSION

The mainstay of management for sacral metastatic tumours is palliation. Preoperative angioembolisation is shown to be of value in cases of highly vascularised tumours. Radiotherapy is used as the primary treatment in cases of inoperable tumours without spinal instability where pain relief and neurological improvement are attainable. Minimal invasive procedures such as sacroplasties were shown to offer immediate pain relief and improvement with ambulation, whereas more aggressive surgery, involving decompression and sacral reconstruction, is utilised mainly for the treatment of local advanced tumours which compromise the stability of the spine or threaten neurological status. Adjuvant cryosurgery and radiosurgery have demonstrated promising results (if no neurological compromise or instability) with local disease control.

Embolisation of bone metastases from renal cancer

PURPOSE

This study was done to evaluate embolisation for palliative and/or adjuvant treatment of bone metastases from renal cell carcinoma and discuss the clinical and imaging results.

MATERIALS AND METHODS

We retrospectively studied 107 patients with bone metastases from renal cell carcinoma treated from December 2002 to January 2011 with 163 embolisations using N-2-butyl cyanoacrylate (NBCA). Mean tumour diameter before embolisation was 8.8 cm and mean follow-up 4 years. Clinical and imaging effects of treatment were evaluated at follow-up examinations with a pain score scale, analgesic use, hypoattenuating areas, tumour size and ossification.

RESULTS

A clinical response was achieved in 157 (96%) and no response in six embolisations of sacroiliac metastases. Mean duration of clinical response was 10 (range 1-12) months. Hypoattenuating areas resembling tumour necrosis were observed in all patients. Variable ossification appeared in 41 patients. Mean maximal tumour diameter after embolisation was 4.0 cm. One patient had intraprocedural tear of the left L3 artery and iliopsoas haemorrhage and was treated with occlusion of the bleeding vessel with NBCA. All patients had variable ischaemic pain that recovered completely within 2-4 days. Postembolisation syndrome was diagnosed after 15 embolisations (9.2%). Transient paraesthesias in the lower extremities were observed after 25 embolisations (25%) of pelvis and sacrum metastatic lesions.

CONCLUSIONS

Embolisation with NBCA is recommended as primary or palliative treatment of bone metastases from renal cell carcinoma. Strict adherence to the principles of transcatheter embolisation is important to avoid complications.

Selective embolization with N-butyl cyanoacrylate for metastatic bone disease

PURPOSE

To evaluate the clinical and imaging effect of selective embolization using N-butyl cyanoacrylate (NBCA) as palliation for bone metastases.

MATERIALS AND METHODS

The procedures and effect of 309 embolizations performed in 243 patients were retrospectively analyzed; 56 patients had repeat embolization at the same location at 1-3 months; 197 patients had embolization for progressive bone metastases after radiation therapy. The mean tumor diameter before embolization was 7.8 cm (range 5-30 cm). In all patients, embolizations were performed under local anesthesia through transfemoral catheterization using NBCA in 33% ethiodized oil. The technical success of embolization was evaluated by angiography after completion of the procedure. The clinical and imaging effect was evaluated at follow-up examinations with a pain score scale and use of analgesics, hypoattenuating areas, tumor size, and ossification.

RESULTS

In all 309 embolizations, postprocedural angiography showed complete occlusion of metastatic blood supply and greater than 80% devascularization of the lesions. Greater than 50% reduction of pain score and analgesic doses was achieved in 97% of procedures. The mean duration of pain relief was 8.1 months (range 1-12 months). The mean maximal tumor diameter after embolization was 5.5 cm (range 2-20 cm). Variable ossification appeared in 65 patients. Postembolization syndrome, ischemic pain at the site of embolization, paresthesias, skin breakdown, and subcutaneous necrosis were observed in 87 patients.

CONCLUSIONS

Selective embolization with NBCA is a safe and effective palliative treatment for metastatic bone lesions of various primary cancers; pain relief is temporary.

The treatment of spinal metastases

BACKGROUND

The rising life expectancy of cancer patients has led to a greater need for treatment of spinal metastases. Interdisciplinary collaboration is important so that each patient's treatment can be properly tailored to the overall prognosis. The main factors to be considered are the histology of the primary tumor, potential spinal instability, and compression of neural structures.

METHODS

We discuss the treatment options for spinal metastases on the basis of a selective literature review and our own extensive experience in an interdisciplinary tumor center.

RESULTS

For spinal canal compression or impending spinal instability, the treatment of choice is decompression and stabilization, by either a dorsal approach (lumbar and thoracic spine) or a ventral approach (cervical spine). Radical ventral tumor resection is indicated only for solitary metastases in patients with a favorable long-range prognosis. If the tumor is radiosensitive, radiotherapy is given either as adjuvant treatment after surgery or as the primary treatment for multiple spinal metastases in the absence of an acute neurological deficit. Various fractionation schemes with different total radiation doses are used. Bisphosphonate treatment is an integral component of the overall treatment strategy.

CONCLUSION

The treatment of spinal metastases requires interdisciplinary collaboration and must be tailored to each patient's overall prognosis.

Interventional management of hypervascular osseous metastasis: role of embolotherapy before orthopedic tumor resection and bone stabilization

OBJECTIVE

The purpose of this study was to evaluate, in relation to intraoperative estimated blood loss (EBL), the effectiveness of preoperative transcatheter arterial embolization of hypervascular osseous metastatic lesions before orthopedic resection and stabilization.

MATERIALS AND METHODS

Between June 1987 and November 2007, 22 patients underwent transcatheter arterial embolization of tumors of the long bone, hip, or vertebrae before resection and stabilization. Osseous metastatic lesions from renal cell carcinoma, malignant melanoma, leiomyosarcoma, and prostate cancer were embolized. All patients were treated with a coaxial catheter technique with polyvinyl alcohol (PVA) particles alone or a combination of PVA particles and coils. After embolization, each tumor was angiographically graded according to devascularization (grades 1-3) based on tumor blush after contrast injection into the main tumor-feeding arteries.

RESULTS

In patients with complete devascularization (grade 1), mean EBL was calculated to be 1,119 mL, whereas in patients with partial embolization (grades 2 and 3) EBL was 1,788 mL and 2,500 mL. With respect to intraoperative EBL, no significant difference between devascularization grades was found (p > 0.05). Moderate correlation (r = 0.51, p = 0.019) was observed between intraoperative EBL and tumor size before embolization. Only low correlation (r = 0.44, p = 0.046) was found between intraoperative EBL and operating time. Major complications included transient palsy of the sciatic nerve and gluteal abscess in one patient.

CONCLUSION

The results of this study support the concept that there is no statistically significant difference among amounts of intraoperative EBL with varying degrees of embolization.

Bone sarcoma of the spine

Primary malignant bone tumors of the vertebral column, i.e., bone sarcomas of the spine, are inherently rare entities. Vertebral osteosarcomas and chordomas represent the largest groups, followed by the incidence of chondro-, fibro-, and Ewing's sarcomas. Detailed clinical and neurological examination, complete radiographic imaging [radiographs, computed tomography (CT), magnetic resonance imaging (MRI)], and biopsy are the decisive diagnostic steps. Oncosurgical staging for spinal tumors can serve as a decision-guidance system for an individual's oncological and surgical treatment. Subsequent treatment decisions are part of an integrated, multimodal oncological concept. Surgical options comprise minimally invasive surgery, palliative stabilization procedures, and curative, wide excisions with complex reconstructions to attain wide or at least marginal resections. The most aggressive mode of surgical resection for primary vertebral column tumors is the total en bloc vertebrectomy, i.e., single- or multilevel en bloc spondylectomy. En bloc spondylectomy involves a posterior or combined anterior/posterior approach, followed by en bloc laminectomy, circumferential (360 degrees) vertebral dissection, and blunt ventral release of the large vessels, intervertebral discectomy and rotation/ en bloc removal of the vertebra along its longitudinal axis. Due to the complex interdisciplinary approach and the challenging surgical resection techniques involved, management of vertebral bone sarcomas is recommended to be performed in specific musculoskeletal tumor centers.

The role of embolization in radical surgery of renal cell carcinoma spinal metastases

BACKGROUND

Radical surgery of renal cell carcinoma spinal metastases carries a high risk due to potentially life-threatening extreme blood loss. Radical preoperative embolization of renal cell carcinoma metastases alone is not necessarily a guarantee of extreme blood loss not occurring during operation.

METHODS

A retrospective analysis of 15 patients following radical surgery for a spinal metastases of a renal cell carcinoma was performed. Eight patients were embolized preoperatively and 7 were not. We analysed features influencing peroperative blood loss: size and extent of tumour, complexity of surgical approaches and radicality of embolization.

RESULTS

The embolized and non embolized groups were not comparable before treatment. They differed markedly in size of tumour as well as the complexity of approach. In the embolized group the size of the tumour was, on average, twice as large as that in non embolized patients and more complex approaches were used twice as frequently. Despite findings suggesting that embolization was effective, blood loss was greater in the embolized group of 8 patients (4750 ml), compared to the non-embolized group of 7 patients (1786 ml).

CONCLUSION

Metastasis size, extent of tumour, technical complexity of surgery and the completeness of preoperative embolization had an important effect on the amount of peroperative blood loss. The evaluation of the benefits of preoperative embolization only on the basis of blood loss is not an adequate method.

Treatment of osteoblastoma at C7: a multidisciplinary approach. A case report and review of the literature

Osteoblastoma is a rare benign bone tumor that presents with back pain and occurs in the spine approximately 40% of the time. The time from onset of symptoms to diagnosis is typically several months because it is a rare entity and radiographic studies are often negative early in the course of the disease. These highly vascular and locally aggressive tumors require complete and precise resection. The patient presented is a 15-year-old boy with a 14-month history of right-sided neck and shoulder pain. Computerized tomography and magnetic resonance imaging demonstrated a lesion in the posterior elements of C7 which extended through the pedicle and into the body. Preoperative angiography confirmed a hypervascular lesion which was successfully embolized. He subsequently underwent piecemeal tumor resection and instrumented fusion. Immediate postoperative imaging demonstrated complete resection. At 18 months follow up the patient has maintained resolution of preoperative symptoms and demonstrates evidence of solid fusion on CT. This multidisciplinary approach markedly decreased blood loss and improved visualization to help achieve complete surgical resection and resolution of clinical symptoms.

Chirurgisches Management von Wirbelsäulenmetastasen

The spine is the most frequent site of skeletal metastases. Among all spinal malignancies metastatic disease is most frequent and indicative of disseminating tumor disease. Depending on primary tumor entity, estimated survival time, general health status of the patient, presence of spinal instability and neurological deficits an oncological useful and patient-specific therapeutic intervention should be performed. New anterior approaches, resections and reconstruction techniques are making surgery a preferred method over radiation therapy. For differential indication of the multiple surgical treatment modalities prognostic scores are available to assist individual decision making. Indications for surgery include survival prognosis of minimum 3 months, intractable pain, progress of myelon compression and/or neurological deficits under radiochemotherapy, spinal instability and necessity for histological diagnosis. Resulting quality of life depends on efficient decompression of the spinal cord and restoration of spinal stability. To achieve these ultimate goals there are different anterior and posterior approaches, instrumentations and vertebral body replacement implants available. Preoperative embolization should be performed in hypervascular tumors, e.g., renal cell cancer. Vertebro-/Kyphoplasty as a percutaneous intervention should be considered for painful multisegmental disease and symptomatic osteolysis without epidural tumor compression to reach analgesia and stability. A multidisciplinary approach in patient selection, decision making and management is an essential precondition for complication avoidance and acceptable quality of life.

Postembolization paralysis in a man with a thoracolumbar giant cell tumor

Giant cell tumors are hypervascular tumors that represent approximately 5% of all primary bone neoplasms. Vertebral tumors often require surgery to maintain spinal stability or to relieve spinal cord and nerve root compression. However, surgical resection of hypervascular tumors like giant cell tumors can be hazardous because of the risk of excessive intraoperative hemorrhage. Preoperative embolization can be useful to decrease perioperative blood loss in primary and metastatic vertebral tumors, and preoperative embolization for vertebral tumor surgery is relatively safe. We report a patient who had the unusual but serious complications of paralysis and paresthesia at the T12 vertebra and below as a result of preoperative embolization. At 6 months followup, the patient was disease-free but without neurologic function from T12 and below. Therefore, it is imperative physicians be aware of the possible preoperative embolization complication of cord infarction and the safety measures proposed in this article to avoid this complication.

Preoperative embolization of hypervascular spinal metastases using percutaneous direct injection with n-butyl cyanoacrylate: technical case report

OBJECTIVE

Intraoperative blood loss constitutes a major cause of perioperative morbidity in surgical decompression and reconstruction of highly vascular spinal metastatic tumors. We propose a technique for embolization of highly vascular vertebral metastases using percutaneous direct injection using n-butyl cyanoacrylate (NBCA) instead of polymethylmethacrylate to complement preoperative transarterial embolization and to minimize operative blood loss.

METHODS

Five patients with renal cell carcinoma metastases to the spine (one cervical, one thoracic, and three lumbar) underwent embolization by percutaneous direct injection of the affected vertebrae with a mixture of NBCA and iodized oil to supplement transarterial embolization with polyvinyl alcohol particles and fibered platinum coils. This was achieved via a transpedicular approach in four cases and by direct vertebral body puncture in one case.

RESULTS

The percutaneous NBCA direct injection procedure was technically successful in all cases and was not associated with neurological or medical complications. All patients underwent subsequent vertebrectomy and spinal instrumentation. Surgical resection was performed with lower than expected blood loss and with a subjective improvement in tumor tissue handling and dissection.

CONCLUSION

The extent of tumor devascularization can be improved by supplementing transarterial embolization with NBCA direct injection to decrease operative blood loss and increase the safety of surgical resection and stabilization of highly vascular spinal metastases.

Influence on spinal cord blood flow and function by interruption of bilateral segmental arteries at up to three levels: experimental study in dogs

STUDY DESIGN

Segmental arteries were interrupted bilaterally at up to three levels to study the influence on spinal cord blood flow (SCBF) and function in dogs.

OBJECTIVES

Considering the need to limit blood loss during surgery for spinal tumors, such as total en bloc spondylectomy, we studied the SCBF and function after experimental interruption of segmental arteries at up to three levels.

SUMMARY OF BACKGROUND DATA

Interruption of bilateral segmental arteries at three consecutive levels (T11, T12, and T13) has reduced blood flow to the vertebral body of T12 by one fourth of the control flow, but effects on the spinal cord have not been determined.

METHODS

SCBF was measured in spinal cord gray matter at T12 using a hydrogen clearance method after ligation of bilateral segmental arteries at 1 to three levels (T11, T12, and T13) in 6 dogs. Spinal cord function was evaluated by spinal cord evoked potentials, motor-evoked potentials, and neurologic assessment in 6 dogs.

RESULTS

SCBF at T12 decreased to 92.4%, 87.8%, and 84.6% of control flow after ligation of bilateral segmental arteries at T12, T11 plus T12, and T11-T13, respectively. Spinal cord evoked potentials and motor-evoked potentials showed no significant changes in any dog after ligation at three levels. No neurologic degradation was observed in any dog.

CONCLUSIONS

Interruption of bilateral segmental arteries at three levels did not damage spinal cord function in dogs, suggesting that in patients, preoperative embolization at three levels to reduce blood loss during surgery for spinal tumors would not compromise spinal cord function.

Preoperative embolization in spinal and pelvic metastases

The role of preoperative embolization should be evaluated for the surgical treatment of spinal and pelvic metastases. Selective embolization was performed in 32 patients (19 men, 13 women; mean age 63.4 years) before surgery by anterior resection of spinal metastases (n = 21) or pelvic metastases (n = 11). Evaluation parameters consisted of the intraoperative blood loss, the need for blood replacement, and the operating time. There was a significant difference in blood loss and transfusion requirements in the spinal group (P = 0.02) as well as in the pelvic group (P = 0.05) compared to a nonembolized control group of spinal (n = 20) and pelvic (n = 10) metastases. The operating time in the embolized group was shorter, but the difference was not significant. Surgical revision was required in two cases in the embolized spinal group owing to necrosis of the psoas muscle. No neurological deficit was observed that could be attributed to the embolization procedure. Preoperative embolization is thus a suitable method for reducing intraoperative blood loss and transfusion requirements in hypervascularized spinal and pelvic metastases.

Embolization of metastatic spinal tumors

Embolization is a safe and valuable primary and adjunctive treatment option for metastatic spinal tumors. Close consultation between the neurosurgeon, the oncologist, the radiation oncologist, and the interventionalist should lead to more applications of embolization techniques,thereby enhancing the treatment of metastatic spinal lesions. The development of newer embolic agents with chemotherapeutic properties should add to the efficacy of embolization for metastatic spinal disease.

Embolization of sacral tumors

The management of sacral tumors is challenging because of difficulties in accessing the lesion, the high rate of local recurrence, extensive vascularity causing significant intraoperative blood loss, resistance to radiation therapy, and risk of malignant transformation. Although surgery is the main treatment for many sacral tumors, embolization is a valuable primary and adjunctive therapy. Patients with benign lesions, including aneurysmal bone cysts and giant cell tumors, have responded to embolization with resolution of their symptoms and with ossification of their lesions. Embolization is used as a primary therapy for metastatic lesions and results in neurological improvement, reduced tumor size, and decreased spinal canal compromise. It is also used as an adjuvant therapy to reduce intraoperative blood loss and to aid in the resection of benign, malignant, and metastatic sacral lesions. It is important to note that embolization techniques are a valuable resource in the treatment of sacral tumors, and, overall, embolization should always be considered in patients with sacral tumors.

Arterial embolization of a secondary aneurysmatic bone cyst of the thoracic spine prior to surgical excision in a 15-year-old girl

We report on a 15-year-old girl with a secondary aneurysmatic bone cyst of the thoracic spine with extension into the spinal canal on the basis of an osteoblastoma. Surgical treatment was facilitated by preoperative embolization of the highly-vascular tumor. Excision of the tumor was performed without extensive intraoperative blood loss. Following excision, transpedicular-stabilization of the spinal column was achieved using a fixateur intern. We conclude that superselective embolization of benign lesions of the spinal column constitutes a feasible means of reducing intraoperative bleeding complications, thus enhancing resectability.

Evaluation and treatment of spinal metastases: an overview

Metastases to the spine are a common and somber manifestation of systemic neoplasia. The incidence of spinal metastases continues to increase, likely a result of increasing survival times for patients with cancer. Historically, surgery for spinal metastases has consisted of simple decompressive laminectomy. Results obtained in retrospective case series, however, have shown that this treatment provides little benefit to the patient. With the advent of better patient-related selection practices, in conjunction with new surgical techniques and improved postoperative care, the ability of surgical therapy to play an important and beneficial role in the multidisciplinary care of cancer patients with spinal disease has improved significantly. Controversy remains, however, with respect to the relative merits of surgery, radiotherapy, chemotherapy, or a combination of these treatments.

In this topic review, the literature on spinal column and spinal cord metastases is collated to provide a description of the presentation, investigations, indications for surgical therapy, and the role of adjuvant cancer therapies for patients with spinal metastases. In addition, the authors discuss the different surgical strategies available in the armamentarium of the neurosurgeon treating patients with spinal metastasis.

Embolization for vertebral metastases of follicular thyroid carcinoma

The technique of selective embolization has been applied for years in the treatment of vascular anomalies, severe hemorrhage and benign or malignant tumors, notably vertebral metastases of renal cell carcinoma. Because this technique is relatively easy to perform and offers immediate relief of symptoms, it is an attractive option for patients with vertebral metastases of thyroid carcinoma with signs of spinal cord compression. In these patients, other treatment modalities like radioactive iodine, external irradiation, or surgery are more cumbersome or less effective in the short term. We describe four patients with metastasized follicular thyroid carcinoma, presenting with neurological symptoms due to vertebral metastases. All patients had undergone total thyroidectomy, ranging from 1 month to 4 yr before embolization. Embolization was combined with iodine-131 therapy when appropriate. Selective catheterization of the arteries feeding the metastases was performed, followed by infusion of polyvinyl alcohol particles (Ivalon). The procedure was technically successful in all patients without adverse effects. In the patients described, embolization resulted in rapid resolution of neurological symptoms, sometimes within hours. The therapeutic effect lasted from months to years. We conclude that embolization of vertebral metastases of follicular thyroid carcinoma is an attractive palliative therapeutic option that may offer rapid relief of symptoms.