Preoperative embolization in spinal and pelvic metastases

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.

Management of metastatic bone disease of the pelvis: current concepts

PURPOSE

Metastatic disease of the pelvis is frequently associated with severe pain and impaired ambulatory function. Depending on the patient's characteristics, primary tumor, and metastatic pelvic disease, the treatment choice may be varied. This study aims to report on the current management options of metastatic pelvic disease.

METHODS

We comprehensively researched multiple databases and evaluated essential studies about current concepts of managing a metastatic bone disease of the pelvis, focusing on specific indications as well as on the result of treatment.

RESULTS

Pelvic metastases not in the periacetabular region can be managed with modification of weight-bearing, analgesics, bisphosphonates, chemotherapy and/or radiotherapy. Minimally invasive approaches include radiofrequency ablation, cryoablation, embolization, percutaneous osteoplasty, and percutaneous screw placement. Pathological or impending periacetabular fracture, excessive periacetabular bone defect, radioresistant tumor, and persistent debilitating pain despite non-surgical treatment and/or minimally invasive procedures can be managed with different surgical techniques. Overall, treatment can be divided into nonoperative, minimally invasive, and operative based on specific indications, the expectations of the patient and the lesion.

CONCLUSION

Different treatment modalities exist to manage metastatic pelvic bone disease. Decision-making for the most appropriate treatment should be made with a multidisciplinary approach based on a case-by-case basis.

The Role of Preoperative Embolization in the Management of Aneurysmal Bone Cyst: A Comparative Analysis

Introduction

The aim of this study was to evaluate the role of preoperative embolization in the management of aneurysmal bone cysts.

Methods

In this study, the data of a total of 19 patients, 11 females and 8 males, with a mean age of 19.6 (range 5-46 years), who were operated on in our hospital with the diagnosis of ABC between January 2015 and January 2021 were retrospectively analyzed. In the specified date range, there were 10 patients with a diagnosis of ABC who were operated on within 48 h after preoperative embolization. For statistical comparison, 9 patients who were operated on without embolization in the same date range were included as the control group.

Results

The mean age of the study group was 16.7 (between 5 and 27 years), while the mean age of the control group was 22.6 (between 16 and 46 years). In the embolization group (group I), the mean intraoperative blood loss was 550 mL (100-1200 mL), the mean intraoperative blood transfusion was 270 mL (0-900 mL), and the mean surgical time was 85 min. In the non-embolization group (group II), the mean intraoperative blood loss was 1250 mL (600-2200 mL), the mean intraoperative blood transfusion was 450 mL (450-1800 mL), and the mean surgical time was 90 min. In comparison, a statistically significant difference was found between the embolization group and the non-embolization group in terms of blood loss and blood transfusion requirement (p = 0.011 and p = 0.017, respectively). The mean surgery time was slightly shorter in the embolized group, and there was no significant difference in surgical time between the two groups (p = 0.821).

Conclusion

Evidence suggests that preoperative embolization of an aneurysmal bone cyst, performed 0-48 h before surgery, can result in a reduction in intraoperative blood loss and intraoperative blood transfusion volume.

Preoperative Embolization of Vertebral Metastasis: Comprehensive Review of the Literature

The aim of this review is to determine the safety and efficacy of pre-operative spinal metastases embolization procedures. Two reviewers independently conducted the literature search (on MEDLINE databases), including in the review of all the studies that used pre-operative TAE to treat spinal metastases. Twelve articles on pre-operative spinal metastases embolization were selected. Most of the studies demonstrated the low complication rate of pre-operative embolization. The most important study strength is that there are very few reviews in the literature with the setting on pre-operative vertebral metastases embolization. A limitation of the review is that the studies included were predominately retrospective case-control studies, increasing the risk of bias in the primary data. Plus, divergent surgical and embolization procedures were performed in the studies, causing a potential risk of bias in the pooled results. We can conclude that preoperative arterial embolization of vertebral metastases is a safe, well-tolerated technique that reduces surgical blood loss and facilitates surgical tumor resection.

Preoperative embolization of renal cell carcinoma metastases to the bone prior to stabilization procedures does not result in reduction in intraoperative blood loss

PURPOSE

The effect of preoperative embolization of bone metastases prior to stabilization procedures in reducing intraoperative blood loss remains controversial. This study aimed to analyze the effect of preoperative embolization on orthopedic stabilization procedures of the extremities and spine in cases with bone metastases from renal cell carcinomas. In particular, do these patients suffer less blood loss during the operation and do they need lesser fluid replacements or packed red cell bags intra- and perioperatively? Does preoperative embolization reduce the duration of surgery?

METHODS

We retrospectively reviewed stabilization procedures of the spine and extremities at our institution between 2011 and 2021 for group differences (embolization vs. no embolization) in terms of blood loss, fluid substitution, need for packed red cell transfusions, tumor size, and duration of surgery.

RESULTS

We reviewed 79 stabilization procedures of the spine (n = 36) and extremities (n = 43), of which 30 included preoperative embolization procedures. Surprisingly, the embolization group showed a statistically significant increase in blood loss, the need for fluid substitution, and red cell transfusions. Subgroup analysis revealed a significant negative effect of preoperative embolization on stabilization procedures of the extremities.

CONCLUSION

Based on our data, preoperative embolization of renal cell carcinoma metastases of the extremities had a negative effect on intraoperative blood loss and the need for fluid substitution and should therefore be avoided. Our data did not show an effect on stabilization procedures of the spine.

Preoperative embolization in surgical treatment of spinal metastases originating from non-hypervascular primary tumors: a propensity score matched study using 495 patients

BACKGROUND CONTEXT

Preoperative embolization (PE) reduces intraoperative blood loss during surgery for spinal metastases of hypervascular primary tumors such as thyroid and renal cell tumors. However, most spinal metastases originate from primary breast, prostate, and lung tumors and it remains unclear whether these and other spinal metastases benefit from PE.

PURPOSE

To assess the (1) efficacy of PE on the amount of intraoperative blood loss and safety in patients with spinal metastases originating from non-hypervascular primary tumors, and (2) secondary outcomes including perioperative allogeneic blood transfusion, anesthesia time, hospitalization, postoperative complication within 30 days, reoperation, 90-day mortality, and 1-year mortality.

STUDY DESIGN

Retrospective propensity-score matched, case-control study at 2 academic tertiary medical centers.

PATIENT SAMPLE

Patients 18 years of age or older undergoing surgery for spinal metastases originating from primary non-thyroid, non-renal cell, and non-hepatocellular tumors between January 1, 2002 and December 31, 2016 were included.

OUTCOME MEASURES

The primary outcomes were estimated amount of intraoperative blood loss and complications attributable to PE, such as neurologic injury, wound infection, thrombosis, or dissection. The secondary outcomes included perioperative allogeneic blood transfusion, anesthesia time, hospitalization, postoperative complication within 30 days, reoperation, 90-day mortality, and 1-year mortality.

METHODS

In total, 495 patients were identified, of which 54 (11%) underwent PE. After propensity score matching on 21 variables, including primary tumor, number of spinal levels, and surgical treatment, 53 non-PE patients were matched to 53 PE patients. Matching was adequate measured by comparing the matched variables, testing the standardized mean differences (<0.25), and inspecting Kernel density plots. The degree of embolization was noted to be complete, until stasis, or successful in 43 (80%) patients.

RESULTS

Intraoperative blood loss did not differ between both groups with a median blood loss in liters of 0.6 (IQR, 0.4-1.2) for non-PE patients and 0.9 (IQR, 0.6-1.2) for PE patients (p=.32). No complications occurred during embolization or the time between embolization and surgery. No differences were found in terms of the secondary outcomes.

CONCLUSIONS

Our data suggest that, although no complications occurred and the embolization procedure can be considered safe, patients with non-hypervascular spinal metastases might not benefit from PE. A larger, prospective study could confirm or refute these study findings and aid in elucidating a subset of spinal metastases that might benefit from PE.

Preoperative arterial embolization and wound complications after resection of malignant bone tumor in the pelvis: a nationwide database study

BACKGROUND

Massive intraoperative blood loss is common in pelvic malignant bone tumor surgery, and preoperative arterial embolization may be used in selected cases. Preoperative arterial embolization reportedly increases wound complications in pelvic fracture surgery, but little evidence is available regarding pelvic bone tumor surgery.

METHODS

Using a Japanese nationwide database (Diagnosis Procedure Combination database), we searched for patients who underwent pelvic malignant bone tumor surgery between July 2010 and March 2018. The primary endpoint was wound complications, defined as any wound requiring re-operation, negative pressure wound therapy or both. Univariate analyses (the chi-squared test for categorical variables, the unpaired t-test for continuous variables) and multivariate logistic regression analyses were performed to examine the association between preoperative arterial embolization and wound complications.

RESULTS

Among the 266 eligible patients, 43 (16%, 43/266) underwent embolization and 69 (26%, 69/266) developed wound complications. In the univariate analyses, preoperative arterial embolization (P < 0.001), duration of anesthesia (P < 0.001), the volume of blood transfusion (P < 0.001) and duration of indwelling drain tube (P < 0.001) were associated with wound complications. In the multivariate logistic regression analysis, preoperative arterial embolization was significantly associated with wound complications (odds ratio, 3.92; 95% confidence interval, 1.80-8.56; P = 0.001).

CONCLUSIONS

Preoperative arterial embolization may be associated with increased wound complications after pelvic malignant tumor surgery.

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

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

Preoperative Embolization of Spinal Metastatic Tumor: The Use of Selective Computed Tomography Angiography for the Detection of Radiculomedullary Arteries

Introduction

Preoperative embolization for metastatic spinal cord compression (MSCC) has a risk of spinal ischemia. This study aimed to assess the efficacy and safety of preoperative embolization in patients with MSCC and evaluate the use of computed tomography (CT) angiography for the detection of the radiculomedullary arteries (RMA).

Methods

This retrospective study included 20 patients (12 men and 8 women; median age, 66 years), who underwent preoperative embolization before a decompression surgery, which corresponded to 22 embolization procedures. The detection ability of RMA was evaluated using angiography and selective CT angiography. Surgical data including intraoperative blood loss and transfusion were also evaluated.

Results

Six RMAs were identified at the levels of affected vertebrae and one level above and below in the diagnostic spinal angiography. In addition to spinal angiography, adjunctive selective CT angiography allowed visualization of another five RMAs. Overall, 11 RMAs were identified in 9 patients. Preoperative embolization was successfully achieved in all patients. As regards complications related to embolization procedure, palsy exacerbated in one patient (4.5%), which improved postoperatively. During the surgical procedure, the mean intraoperative blood loss was 353.4±254.2 mL without intraoperative transfusion in all patients.

Conclusions

The present study showed small amounts of intraoperative blood loss without any severe complications related to preoperative embolization. Selective CT angiography was a useful technique to detect RMAs and contributed to the safety of preoperative embolization.

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.

Perioperative blood loss after embolization of hypervascular musculoskeletal tumors outside of the spine: A single-center ten year experience and systematic review of the literature

PURPOSE

To evaluate outcomes following trans-arterial embolization of hypervascular appendicular bony tumors in patients undergoing orthopedic resection by performing a systematic review including data from the authors' institution.

MATERIALS AND METHODS

From April 2008 to August 2018, 73 patients (59 males, mean age 58.1 years) with musculoskeletal tumors presented for embolization for preoperative devascularization prior to orthopedic surgery. A retrospective chart review was performed to identify demographic, procedural and surgical data. A systematic review of the Pubmed, Medline, and Web of Science databases was performed to identify studies in which pre-operative embolization was performed of appendicular MSK tumors, and with measurements of estimated blood loss. All the variables listed above were recorded. A patient level analysis was performed to determine average estimated blood loss.

RESULTS

58 patients (47 men, 11 women, range 21-84 years) were included in our institutional analysis. The median EBL was 500 mL (range 100-3000). There was no difference in EBL between RCC (719.6 ± 626.1) and non-RCC groups (855.6 ± 657.5); p = 0.44. The median intra-operative transfusion requirement was 1.0 unit (range 0-8 ± 2.06). From 1984 to 2015, 9 studies were identified that provided data for a total of 118 patients (46 males, 42 females, range 10-82 years). The mean and median post-surgical EBL across all patients was 976.9 ± 78.5 (SE) and 725 mL (range 10-7000), respectively. There were no complications related to non-target embolization.

CONCLUSION

Preoperative trans-arterial embolization of hypervascular MSK neoplasms appears to be safe and effective in minimizing peri- and post-operative bleeding while keeping transfusion requirements low.

Prolonged balloon occlusion of the lower abdominal aorta during pelvic or sacral tumor resection

Background

To explore the efficacy of lower abdominal aorta balloon occlusion technology in pelvis and sacral tumor surgery and to assess the safety of prolonged balloon occlusion.

Methods

From January 2008 to January 2017, 81 patients were diagnosed with sacrum or pelvic tumor and underwent surgery in our institution. Balloon catheters were placed through the femoral artery to occlude the abdominal aorta of the pelvic tumor and sacrum region undergoing tumor resection. These patients were divided into two group based on single balloon blocking time. Group A had a balloon blocking time of 60 minutes or less, and group B had a balloon occlusion time greater than 60 minutes. The patients in the two groups were compared with regards to operation time, intraoperative blood loss, blood transfusion volume, average length of hospital stay, and postoperative complications.

Results

No balloon displacement or leakage of the abdominal aorta occurred during the operations. The difference in operation time between the two groups was statistically significant (P≤0.05), and the differences in intraoperative blood loss, blood transfusion volume, and average hospital stay between groups A and B were not significant (P>0.05). The incidence of postoperative complications was 12% in group A, and 22.6% in group B, with no statistically significant differences (P>0.05).

Conclusions

Prolonged balloon occlusion was safe and effective in the surgical treatment of complicated pelvic and sacral tumors. It did not increase the incidence of postoperative complications such as distal limb paralysis, arterial thrombosis, or ischemic necrosis.

Total hip arthroplasty with reconstruction of acetabulum through direct anterior approach for metastatic bone disease of acetabulum combined with pathological proximal femoral neck fracture: A case report

Most surgical treatment options for metastatic acetabular lesions involve variants of total hip arthroplasty (THA). However, these are technically complex reconstructions performed in very frail patients, and previous reports indicate complications such as dislocation, deep infection, aseptic loosening, and intraoperative death. A 73-year-old man presented to the emergency department at our hospital with right hip pain following a fall. He had undergone nephrectomy for the treatment of right kidney cancer at the age of 68 years. Four years after the nephrectomy, multiple lung metastases, pelvic bone metastases, and right femoral head and neck bone metastases were found. A radiograph of the hip joint showed a pathological proximal femoral fracture with a radiolucent lesion of the acetabulum. THA with acetabular reconstruction using a Kerboull-type (KT) plate through the direct anterior approach (DAA) was performed. After removal of the femoral head, curettage of the metastatic acetabular dome lesion was carefully performed under fluoroscopic guidance. After the KT plate was placed, cementation of the metastatic acetabular dome lesion was performed, and an optimally sized polyethylene liner was fixed with cement. A cemented stem was inserted after confirming the hip joint stability. At the 14-month follow-up, he could walk steadily without any complications and his modified Harris hip score was 100. The DAA conserves soft tissue because it is an intermuscular approach. Accordingly, postoperative recovery is fast and thus associated with a low dislocation rate and effective pain reduction. The acetabulum with metastatic disease was reconstructed using a KT plate for hip joint stability. Bone with metastatic disease that appears adequate at the time of THA may become incompetent after a few years. THA with acetabular reconstruction using a KT plate through the DAA was an effective treatment for metastatic bone disease of the acetabulum combined with pathological proximal femoral neck fracture.

A clinical calculator for predicting intraoperative blood loss and transfusion risk in spine tumor patients

BACKGROUND CONTEXT

Surgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death.

PURPOSE

To develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors.

STUDY DESIGN/SETTING

Retrospective, single-center study.

PATIENT SAMPLE

Consecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer center OUTCOME MEASURES: IOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused.

METHODS

We identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression.

RESULTS

Mean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (β=25.43 per point; p<0.001), and preoperative albumin (β=-244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/).

CONCLUSIONS

Here we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion.

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.

Transcatheter Arterial Embolization Using Microspheres for Palliating Pain from Bone Metastasis in a Patient with Cholangiocellular Carcinoma

A 72-year-old man with intractable left shoulder pain due to bone metastasis from cholangiocellular carcinoma was admitted to our hospital. Computed tomography showed an osteoblastic metastatic lesion of the left scapula. Since the pain persisted even after the administration of opioids and external irradiation, microspheres were injected through a catheter; the catheter tip was placed at the arteries feeding the metastatic lesion. After the intervention, the shoulder pain was alleviated without any procedure-related complications, leading to a reduction in the opioid dose. This case suggests the efficacy of transcatheter arterial embolization using microspheres for palliating pain from bone metastasis.

Electrochemotherapy and Simultaneous Photodynamic Bone Stabilization of Upper Limbs in Metastatic Renal Cancer Disease: Case Report and Literature Review

Introduction

Metastatic bone disease represents a systemic pathology that heavily affects the quality of life of oncologic patients causing pain and functional disability. Methodology. We present the case of a patient with a history of renal cell cancer presenting pathologic fractures of both humeri and proximal right radius.

Results

After a careful multidisciplinary approach, an adjuvant anticancer therapy and a photodynamic bone stabilization procedure were performed with a minimally invasive technique aiming to minimize pain and local disease progression, while restoring functional autonomy and improving the patient's quality of life. Electrochemotherapy was delivered on the lytic bone lesions with extraskeletal involvement of the proximal left humerus and the proximal right radius, and then polymeric bone stabilization was performed on both humeri. At two months of follow-up, the patient presented satisfactory functional scores (MSTS score: 12/30 bilaterally; DASH scores: 46.7/100 for the right side and 48.3/100 for the left one), and pain was well controlled with opioid analgesics. Radiographs showed good results in terms of ossification of lytic bone lesions and durability of polymeric stabilization. At four months of follow-up, the patient reported a stable clinical scenario. Six months after surgery, due to extremely poor prognosis after the progression of primary disease, the patient was referred to palliative care and died shortly thereafter.

Conclusion

Over the last decade, the management of metastatic bone disease has changed. Low-toxicity and minimally invasive procedures such as electrochemotherapy and polymeric bone stabilization might be performed concomitantly in selected patients, as an alternative to radiation therapy and to more demanding surgical procedures such as plating and adjuvant cementing.

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.

Update on Preoperative Embolization of Bone Metastases

Management of patients with bone metastasis is complex and should include different specialties. Goals of therapy should be identified for each individual patient prior to the start of treatment. Preoperative embolization has generally been considered a safe and effective means of reducing intraoperative blood loss with recent studies and advances in technique reported. Update on indications, contraindications, technique, and efficacy, as well as prognostic factors and complications of preoperative embolization of bone metastases will be reviewed. New trends such as transradial arterial access and usage of liquid embolic agents will be discussed. Large tumor size, increased preprocedural tumor vascularity, longer embolization-to-surgery interval, and radical surgical procedures are associated with greater intraoperative blood loss and prolonged operative time. An accurate, noninvasive method to evaluate tumor vascularity prior to angiography is needed to identify patients who are most likely to benefit from preoperative embolization. Particular attention will be paid to skeletal metastases and spinal metastases as each has its own set of complexity.

The evolution of pre-operative spine tumour embolization

Pre-operative spine tumour embolization is a useful adjunct to minimize operative complications and blood loss during complex resections. While the efficacy of this procedure has been well studied, relatively little is documented regarding how to optimize technical parameters for tumour characteristics. This pictorial case series seeks to review our centre's experience over the last decade in using a range of embolization techniques. As experience with this procedure has matured, we propose an approach based on the patient's vascular anatomy and tumour angioarchitecture. This includes the use of coils as protective barriers rather than primary embolics; particle embolization to permeate fine capillary networks; consideration for liquid embolic agents in the presence of large caliber tumour vessels with associated arteriovenous shunting; and percutaneous intralesional embolization when endovascular access is insufficient to achieve the desired outcome. In many cases, a combination of these methods is needed, and close communication with the surgeon ensures the best outcome. Despite these advances, continued work is needed to determine how to optimize complete devascularization, and thus surgical benefit, while safely sparing critical neuroanatomical structures.

Clinical Significance of Preoperative Embolization for Non-Hypervascular Metastatic Spine Tumors

OBJECTIVE

The efficacy of preoperative embolization for hypervascular metastatic spine disease (MSD) such as renal cell and thyroid cancers has been reported. However, the debate on the efficacy of preoperative embolization for non-hypervascular MSD still remains unsettled. The purpose of this study is to determine whether preoperative embolization for non-hypervascular MSD decreases perioperative blood loss.

METHODS

A total of 79 patients (36 cases of preoperative embolization and 43 cases of non-embolization) who underwent surgery for metastatic spine lesions were included. Representative hypervascular tumors such as renal cell and thyroid cancers were excluded. Intraoperative and perioperative estimated blood losses (EBL), total number of transfusion and calibrated EBL were recorded in the embolization and non-embolization groups. The differences in EBL were also compared along with the type of surgery. In addition, the incidence of Adamkiewicz artery and complications of embolization were assessed.

RESULTS

The average age of 50 males and 29 females was 57.6±13.5 years. Lung (30), hepatocellular (14), gastrointestinal (nine) and others (26) were the primary cancers. The demographic data was not significantly different between the embolization and the non-embolization groups. There were no significant differences in intraoperative EBL, perioperative EBL, total transfusion and calibrated EBL between two groups. However, intraoperative EBL and total transfusion in patients with preoperative embolization were significantly lower than in non-embolization in the corpectomy group (1645.5 vs. 892.6 mL, p=0.017 for intraoperative EBL and 6.1 vs. 3.9, p=0.018 for number of transfusion). In addition, the presence of Adamkiewicz artery at the index level was noted in two patients. Disruption of this major feeder artery resulted in significant changes in intraoperative neuromonitoring.

CONCLUSION

Preoperative embolization for non-hypervascular MSD did not reduce perioperative blood loss. However, the embolization significantly reduced intraoperative bleeding and total transfusion in corpectomy group. Moreover, the procedure provided insights into the anatomy of tumor and spinal cord vasculature.

Which is the better timing between embolization and surgery for hypervascular spinal tumors, the same day or the next day?: A retrospective comparative study

Previous series presented the timing between embolization and surgery in a wide range on the basis of their experience rather than supportive data. And comparative studies were limited to small samples. In addition, there is no study publishing the timing by considering both safety and efficacy of embolization. The aim of this study was to determine the better timing (the same day or the next day) between embolization and surgery for hypervascular spinal tumors by assessing the safety and efficacy of embolization.One hundred twenty-five embolizations with subsequent 120 operations for hypervascular spinal tumors between January 2010 and April 2013 were retrospectively reviewed. The time between embolization and surgery was mainly determined by interventional radiologist schedules and operating room available. Major complications of embolization were documented. The efficacy of embolization was compared between the same day and the next day group.Of the 125 embolizations, there were 4 major complications, all of which occurred on the same day of procedure. Of the 120 operations, 36 cases were operated on the same day of embolization, 74 on the next day, and 10 on the second day. When comparing the efficacy of embolization between the same day and the next day group, intraoperative blood loss (1483 ± 1475 vs 1548 ± 1099 mL, P = .80), intraoperative transfusion requirement (1011 ± 1200 vs 1112 ± 890 mL, P = .62), and postoperative blood loss (1146 ± 933 vs 1031 ± 777 mL, P = .50) were not significantly different.Embolization carries certain risks (4/125, 3.2%) for major complications, which may occur within the time window of 1 day. Two patient groups showed no difference on the efficacy of embolization. Operation should be scheduled on the next day of embolization if possible.

Not All Patients Undergoing Stabilization of Impending Pathologic Fractures for Renal Cell Carcinoma Metastases to the Femur Need Preoperative Embolization

BACKGROUND

Preoperative transarterial embolization has been utilized in the surgical treatment of metastatic renal cell carcinoma of the femur to decrease perioperative blood loss. However, few studies have documented its efficacy in decreasing the proportion of patients receiving transfusions in the setting of prophylactic treatment of impending pathologic femur fractures.

QUESTIONS/PURPOSES

In a population of patients with metastatic renal cell carcinoma of the femur who underwent prophylactic fixation, the purpose of this study was to quantify and compare the proportion of patients who received at least one transfused unit of blood between a group treated with preoperative embolization and a group without preoperative embolization.

METHODS

A retrospective study was performed using a Medicare claims-based database. International Classification of Diseases, 9 Revision and Current Procedural Terminology codes were used to identify 1285 patients with metastatic renal cell carcinoma of the femur who underwent prophylactic fixation. The proportion of patients who received one or more blood transfusions was compared between 135 patients who underwent preoperative embolization and a group of 1150 concurrent control patients who did not undergo preoperative embolization. The control group was older than the embolization group, with 44% of these patients > 75 years old and 33% of the embolization group > 75 years. There was no difference in the female:male ratio between groups. Statistical comparisons of outcomes related to transfusion percentages were performed using Pearson chi square analysis with p < 0.05 considered significant. With the numbers available, we had 80% power to detect a difference in the percentage of patients transfused of 11% between the study groups at α = 0.05.

RESULTS

No difference in transfusion percentage was observed between preoperative transarterial embolization (41 of 135 [30%]) and the control group (359 of 1150 [31%]; relative risk, 0.973; 95% confidence interval, 0.743-1.274; p = 0.84). The percentage of all patients who received a transfusion was 31% (400 of 1285).

CONCLUSIONS

Preoperative embolization may not be mandatory in the prophylactic treatment of metastatic renal cell carcinoma of the femur, as demonstrated by the 69% of patients who received zero units of blood despite not receiving embolization. However, assessment of the efficacy of embolization in decreasing blood loss in the current study is limited as a result of biases associated with the database design of the study; the decision of whether to send a patient for embolization should be made on a case-by-case basis. The current study does not identify specific risk factors that should factor into this decision and underscores the need for further research in this regard. A plausible future research design to account for the low numbers and selection bias that limited the current study as well as the existing studies might be a multicenter, retrospective case-control study.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Systematic review and meta-analysis of effectiveness of preoperative embolization in surgery for metastatic spine disease

Background

Preoperative embolization (PE) may decrease intraoperative blood loss (IBL) in decompressive surgery of hypervascular spinal metastases. However, no consensus has been found in other metastases and no meta-analysis which reviewed the benefit of PE in spinal metastases has been conducted.

Objective

To assess IBL in spinal metastases surgery in a randomized controlled trial (RCT) and cohort studies comparing PE and a control group of non-embolized patients.

Methods

A systematic search of relevant publications in PubMed and EMBASE was undertaken. Inclusion criteria were RCTs and observational studies in patients with spinal metastases who underwent spine surgery and reported IBL. Meta-analysis was performed using standardized mean difference (SMD) and mean difference (MD) of IBL. Heterogeneity was assessed using the I2 statistic.

Results

A total of 265 abstracts (126 from PubMed and 139 from Embase) were identified through database searching. The reviewers selected six studies for qualitative synthesis and meta-analysis. The pooled SMD of the included studies was 0.58 (95% CI −0.10 to 1.25, p=0.09). Sensitivity analysis revealed that, if the study by Rehak et al was omitted, the pooled SMD was significantly changed to 0.88 (95% CI 0.39 to 1.36, p<0.001) and PE reduced the IBL significantly. The pooled MD was 708.3 mL (95% CI −224.4 to 1640.9 mL, p=0.14). If the results of the Rehak et al study were omitted, the pooled MD was significantly changed to 1226.9 mL (95% CI 345.8 to 2108.1 mL, p=0.006).

Conclusions

PE can be effective in reducing IBL in spinal metastases surgery in both renal cell carcinoma and mixed primary tumor groups.

Successful selective arterial embolizations for bone metastases in renal cell carcinoma integrated with systemic therapies: A case report

Herein is described the case of a 64-year-old patient affected by metastatic clear-cell carcinoma, with exclusive bone disease, subjected after the initial cytoreductive nephrectomy to 3 successive lines of medical treatment (sunitinib, everolimus, and sorafenib) and multiple locoregional treatments (spinal surgery, radiation therapy, and selective arterial embolization), resulting in a surprisingly long survival of over 75 months. In the era of target therapy, integration strategies, including additional locoregional treatment to medical therapy, are essential to optimize the clinical benefit, to maximize treatment duration overcoming focal progressive disease, and to improve the quality of life. In this context, we would highlight that selective transcatheter embolization of bone metastases from renal cell carcinoma should be considered as an effective and safe option in the palliative setting for patients with bone metastasis, especially for pain relief.

Current orthopaedic management of bony metastases in the proximal third of the femur

Patients presenting with skeletal metastatic lesions requiring surgery are increasing, this is due to an ageing population and improved oncological survival following advances in medical management. Furthermore, patients are living longer with skeletal metastatic disease. The majority of bone metastases occur in the proximal femur. Robust diagnosis (Biopsy) and treatment is required to ensure that patients can mobilise fully weight bearing immediately post-surgery and that the construct should outlive the patients expected survival. We review the changing management of metastatic disease in the proximal femur.

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.

Surgery of non-spinal skeletal metastases in renal cell carcinoma: No effect of preoperative embolization?

BACKGROUND AND PURPOSE

Surgery for metastases of renal cell carcinoma has increased in the last decade. It carries a risk of massive blood loss, as tumors are hypervascular and the surgery is often extensive. Preoperative embolization is believed to facilitate surgery. We evaluated the effect of preoperative embolization and resection margin on intraoperative blood loss, operation time, and survival in non-spinal skeletal metastases of renal cell carcinoma.

PATIENTS AND METHODS

This retrospective study involved 144 patients, 56 of which were treated preoperatively with embolization. The primary outcome was intraoperative blood loss. We also identified factors affecting operating time and survival.

RESULTS

We did not find statistically significant effects on intraoperative blood loss of preoperative embolization of skeletal non-spinal metastases. Pelvic localization and large tumor size increased intraoperative blood loss. Marginal resection compared to intralesional resection, nephrectomy, level of hemoglobin, and solitary metastases were associated with better survival.

INTERPRETATION

Tumor size, but not embolization, was an independent factor for intraoperative blood loss. Marginal resection rather than intralesional resection should be the gold standard treatment for skeletal metastases in non-spinal renal cell carcinoma, especially in the case of a solitary lesion, as this improved the overall survival.

Spinal interventions

We review the state of the art in imaging-guided percutaneous interventional procedures used to diagnose and/or treat the diverse causes of back pain. These procedures can be used for diagnosis, treatment, or both. They are focused on the vertebral bodies, the facet joints, the intervertebral discs, and the nerve structures.

Preoperative arterial embolization facilitates multivisceral transplantation for portomesenteric thrombosis

Multivisceral transplantation (MvTx) for diffuse venous portomesenteric thrombosis is a surgically and anesthesiologically challenging procedure, partly because of the risk of massive bleeding during visceral exenteration. Preoperative visceral artery embolization might reduce this risk. In three consecutive MvTx, the celiac trunk (CT) and superior mesenteric artery (SMA) were embolized immediately pretransplant. We analyzed demographics, serum D-lactate, pH, base excess, hemoglobin, blood pressure, transfused packed cell (PC) units, intervention time and outcome. Results are reported as median (range). All recipients were male (43, 22, 47 years old). Portomesenteric thrombosis followed antiphospholipid syndrome, neuroendocrine tumor and liver cirrhosis. A peritransplant D-lactate peak of 6.1 (5.1-7.6) mmol/L, lowest pH of 7.24 (7.18-7.36) and lowest base excess level of -9.5 (-7.6 to -11.5) were observed. Values normalized within 3 h posttransplant. Embolization and exenteration times were 80 (70-90) min and 140 (130-165) min, respectively, during which blood pressure remained stable, lowest hemoglobin was 6.1 (6.1-7.6) g/dL and three (2-4) PC were administered. All procedures were uneventful. Follow-up was 7 (4-9) months. The first patient died 4 months post-MvTx after an intracranial bleeding; the other patients are doing well. Our experience suggests that preoperative embolization of CT and SMA facilitates native organ resection in MvTx.

The efficacy and risks of preoperative embolization of spinal tumors

Background

The goal of preoperative embolization of spinal tumors is to improve surgical outcomes by diminishing the vascular supply to the tumor to reduce intraoperative blood loss and operative time.

Objective

To report our institutional experience with spinal tumor embolization and review the present literature.

Methods

Clinical records from January 1, 2001 to December 31, 2012 were reviewed and analyzed. Angiograms were used to calculate the percentage reduction in tumor vascularity, and relevant clinical and operative data were collected and analyzed.

Results

Thirty-seven patients underwent preoperative spinal tumor embolization (24 metastatic and 13 primary lesions) and were included in the study. One complication resulted in transient lower extremity weakness and was attributed to post-embolization swelling, which fully resolved after surgical resection. The transient neurological complication rate was 1/37 (3%) and the permanent rate was 0/37 (0%). The average surgical estimated blood loss (EBL) was 1946 mL (100–7000 mL) and the average operative time was 330 min (range 164–841 min). After embolization, tumor blush was reduced by 83% on average. Average pre- and postoperative modified Rankin Scale scores were 2.10 and 1.36, respectively (p=0.03). Cases in which tumor blush was decreased by ≥90% (classes 1 or 2) after embolization had significantly less operative blood loss than those cases in which <90% (classes 3 or 4) was achieved (mean EBL 1391 vs 2296 mL, respectively, p=0.05).

Conclusions

Spinal tumor embolization is a safe procedure, is associated with few complications, and may improve surgical outcomes by limiting intraoperative blood loss and reducing operative time.

Embolization of hypervascular bone metastases reduces intraoperative blood loss: a case-control study

BACKGROUND

Small case series suggest that preoperative transcatheter arterial embolization minimizes bleeding and facilitates surgery for hypervascular metastatic bone tumors. However, control groups would make our confidence in clinical recommendations stronger, but small patient numbers make prospective trials difficult to conduct on this topic.

QUESTIONS/PURPOSES

In this case-control study, we asked whether (1) patients who undergo embolization have less estimated blood loss and/or shorter operative time than patients who do not have embolization; (2) larger tumor size, greater initial tumor vascularity, and longer interval from embolization to surgery are associated with greater estimated blood loss and packed red blood cell transfusion volume; and (3) embolization does not affect renal function in patients with normal preoperative renal function.

METHODS

We retrospectively reviewed records of patients with hypervascular bone metastases treated at our institution between 1998 and 2008. Twenty-seven patients with renal cell carcinoma and 12 with thyroid carcinoma who underwent embolization before 41 surgical procedures were matched to 41 patients who did not have embolization with respect to age, diagnosis, tumor size and potential vascularity, and procedure type; matching was performed without knowledge of outcomes. In univariate and multivariate analyses, age, tumor size, use of embolization, surgery type and risk, embolization-to-surgery interval, and degree of devascularization were evaluated for correlations with estimated blood loss, packed red blood cell transfusion volume, operative time, and postembolization renal function.

RESULTS

Overall, patients who had embolization had less mean estimated blood loss (0.90 versus 1.77 L; p = 0.002), packed red blood cell transfusion volume (2.15 versus 3.56 U; p = 0.020), and operative time (3.13 versus 3.91 hours; p < 0.001). Larger tumor size correlated with greater estimated blood loss (r = 0.451; p = 0.003), packed red blood cell transfusion volume (r = 0.50; p = 0.002), and operative time (r = 0.595; p < 0.001). Neither the interval for embolization to surgery nor the degree of devascularization correlated with estimated blood loss or transfusion volume. In open rodding with intralesional curettage, transcatheter arterial embolization was associated with reduced estimated blood loss, transfusion volume, and operative time. Packed red blood cell transfusion volume was not reduced by embolization in intramedullary nailing procedures with the patient numbers available. Among patients with normal preoperative renal function who had embolization, creatinine levels remained normal. Mild transient, reversible renal function change occurred in one patient with preoperatively abnormal renal function.

CONCLUSIONS

This study suggests that preoperative embolization probably reduces estimated blood loss, particularly for large tumors and during open femoral procedures.

Dynamic contrast-enhanced magnetic resonance perfusion compared with digital subtraction angiography for the evaluation of extradural spinal metastases: a pilot study

STUDY DESIGN

This was a retrospective study comparing dynamic contrast-enhanced magnetic resonance (DCE-MR) perfusion with digital subtraction angiography (DSA) in determining the vascularity of spinal tumors.

OBJECTIVE

To report on the efficacy of DCE-MR perfusion as a potential noninvasive surrogate for measuring vascularity and thus determine the need for preoperative embolization.

SUMMARY OF BACKGROUND DATA

Although primary spinal tumors are rare, spine metastases are relatively common and symptomatic in approximately 14% of patients. Symptomatic patients require palliation with radiotherapy and/or surgery, with possible preoperative endovascular embolization of the tumor.

METHODS

A retrospective review revealed 10 patients with 11 diseased vertebral bodies who had received spine DCE-MR perfusion studies and subsequently underwent spinal DSA. Processed MR data were used to calculate a blood flow ratio comparing blood flow with a diseased and an adjacent normal vertebral body. Spinal tumor vascularity was graded on the basis of angiographic tumor blush from 0 (decreased enhancement compared with a normal vertebral body) to 4 (marked tumor blush with early arteriovenous shunting).

RESULTS

Eight vertebral bodies demonstrated increased vascularity on DSA with blood flow ratios of greater than 1.8, 2 vertebral bodies demonstrated normal enhancement on DSA with cerebral blood flow (CBF) ratio of 0.55 to 1.14, and 1 vertebral body level had decreased enhancement on DSA, with a CBF ratio of 0.43. There was a strong correlation between CBF ratio and DSA score, with Spearman ρ = 0.87 (P = 0.00012).

CONCLUSION

These data show a statistically significant correlation between CBF ratio and DSA and suggest that DCE-MR perfusion can serve as a surrogate to DSA for determining tumor vascularity in patients with extramedullary spinal metastases.

Evaluation and treatment of spinal metastatic disease

With the increased survival of oncologic patients, evaluation and management of patients with spinal metastasis is crucial to reducing morbidity and maximizing function. In this chapter, we present some guidelines for the initial systematic evaluation of patients with spinal lesions, as well as the risks, benefits, and alternatives to nonoperative and operative management of metastatic spinal disease, and the overall survival of these patients.

MRI Characterization of Vascular Spinal Tumors

STUDY DESIGN

Randomized trial.

OBJECTIVE

This study described practical magnetic resonance imaging (MRI) characteristics to assist in the identification of these tumors including the corresponding statistics.

SUMMARY OF BACKGROUND DATA

Identification of vascular spinal tumors using MRI allows the opportunity for angiography and preoperative embolization (PE) to improve outcomes and decrease hemorrhage. The MRI characterization reliability of these tumors has not been described.

MATERIALS AND METHODS

A retrospective comparison of 40 patients, at a single institution, with known spinal tumors was conducted with 20 vascular versus 20 nonvascular cases (based on postoperative pathology). Randomized MRI T1 precontrast/postcontrast and T2 images of these tumors were blinded and reviewed by 7 spine surgeons and 5 musculoskeletal radiologists. Four criteria were reviewed: T2 hyperintensity, contrast enhancement, flow voids, and feeding vessels. The clinical relevance was evaluated by asking if the reviewer recommended PE.

RESULTS

The specificity, sensitivity, and accuracy of each characteristic for surgeons were: T2 hyperintensity (65%, 85%, 75%), contrast enhancement (84%, 38%, 61%), flow voids (42%, 86%, 64%), and feeding vessels (35%, 90%, 63%). The results for the radiologists were: T2 hyperintensity (83%, 61%, 72%), contrast enhancement (87%, 32%, 60%), flow voids (44%, 93%, 69%), and feeding vessels (33%, 93%, 63%). Both the groups had low κ and intraclass correlation values. Review of angiography/PE recommendation showed that both surgeons and radiologists had a false-negative rate of 33%.

CONCLUSIONS

Surgeons and radiologists have similar moderate accuracy of MRI vascularity identification. Radiologists have a higher sensitivity, but lower specificity. Even with simplified, straightforward criteria, the MRI characterization of vascular spinal tumors has low interobserver/intraobserver reliability with a false-negative rate for angiography/PE recommendation of 33%. Angiography may become more standard in the workup of spine tumors.

Management of metastatic bone disease of the acetabulum

Metastatic acetabular disease can be severely painful and may result in loss of mobility. Initial management may consist of diphosphonates, narcotic analgesics, radiation therapy, protected weight bearing, cementoplasty, and radiofrequency ablation. Patients with disease affecting large weight-bearing regions of the acetabulum and with impending failure of the hip joint are unlikely to gain much relief from nonsurgical treatment and interventional procedures. The profound osteopenia of the acetabulum, limited healing potential of the fracture, and projected patient life span and function necessitate surgical techniques that provide immediate stable fixation to reduce pain and restore ambulatory function. Current reconstructive procedures, including cemented total hip arthroplasty, the saddle or periacetabular endoprosthesis, and porous tantalum implants, are based on the quality of remaining acetabular bone as well as the patient's level of function and general health. Well-executed acetabular reconstructions can provide durable hip joints with good pain relief and function.

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 evaluation for lower abdominal aorta balloon occluding in the pelvic and sacral tumor resection

OBJECTIVE

To investigate the values of clinical application of lower abdominal aorta balloon occluding in the pelvic and sacral tumor resection.

METHOD

From January 2004 to January 2010, 137 patients were diagnosed as sacral or pelvic tumors and underwent surgery in our institution. Forty-five patients underwent resection combined with lower abdominal aorta balloon occluding to control hemorrhage (balloon occluding group), the remaining 92 patients underwent conventional resection (conventional therapy group). We compared operative time, intraoperative hemorrhage, the amount of blood transfusion, postoperative complications, mean hospital stay as well as rates of tumor recurrence or metastasis at 3 years.

RESULTS

En-bloc resection was performed in 93.3% (42/45) patients in balloon occluding group while the conventional therapy group was 78.2% (79/92). The balloon occluding group showed significantly shorter mean operating time, lower blood loss, lower blood transfusion, and lower postoperative drainage volume than did the conventional therapy group. The two treatment groups showed no significant difference in mean hospital stay, frequency of postoperative complications or rates of tumor recurrence or metastasis at 3 years.

CONCLUSION

The application of lower abdominal aorta balloon occluding to control hemorrhage during the surgery contributes to a more clear operation field, less operation time as well as less blood loss and blood transfusion. Moderate prolong of the occluding duration can improve the safety of the surgery and contribute to more radical resection of the tumor without increase of the risks for complications.

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.

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.

Preoperative and therapeutic embolization of extremities of bone and soft tissue tumors

Embolization of bone and soft tissue tumors has a broad range of indications, from curative treatment to palliation. The main purpose of embolization is to occlude as much of the tumor blood supply as possible. The outcome ranges from complete tumor devascularization and necrosis to degrees of ischemia and hypovascularity. Thus, the tumor will shrink, bleeding will be reduced, borders between the tumor and surrounding tissue will become clear, and resection will be easier. The purpose of this study was to correlate the effectiveness of preoperative embolization with the blood loss and transfusion requirement during surgery for bone or soft tissue tumors.