Treatment Of Metastatic Spine Disease Research Articles

Gender and Sex Differences in Health-related Quality of Life, Clinical Outcomes and Survival after Treatment of Metastatic Spine Disease.

Retrospective review of prospective, multicenter and international cohort study. To describe the effect of gender on HRQoL, clinical outcomes and survival for patients with spinal metastases treated with either surgery and/or radiation. Gender differences in health-related outcomes are demonstrated in numerous studies, with women experiencing worse outcomes and receiving lower standards of care than men, however, the influence that gender has on low health-related quality of life (HRQoL) and clinical outcomes after spine surgery remains unclear. Patient demographic data, overall survival, treatment details, perioperative complications, and HRQoL measures including EQ-5D, pain NRS, the short form 36 version 2 (SF-36v2) and the Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0) were reviewed. Patients were stratified by sex, and a separate sensitivity analysis that excluded gender-specific cancers (i.e., breast, prostate, etc.) was performed. The study cohort included 207 female and 183 male patients, with age, smoking status, and site of primary cancer being significantly different between the two cohorts (P<0.001). Both males and females experienced significantly improved SOSGOQ2.0, EQ-5D, and pain NRS scores at all study time points from baseline (P<0.001). Upon sensitivity analysis, (gender-specific cancers removed from analysis), the significant improvement in SOSGOQ physical, mental, and social subdomains and on SF-36 domains disappeared for females. Males experienced higher rates of postoperative complications. Kaplan-Meier survival analysis of both the overall and sensitivity analysis cohorts showed females lived longer than males after treatment (P=0.001 and 0.043, respectively). Both males and females experienced significantly improved HRQoL scores after treatment, but females demonstrated longer survival and a lower complication rate. This study suggests that gender may be a prognostic factor in survival and clinical outcomes for patients undergoing treatment for spine metastases and should be taken into consideration when counseling patients accordingly.

NCMP-09. THE CURRENT LANDSCAPE OF SPINE ONCOLOGY SURGICAL TRIALS AND FUTURE OPPORTUNITIES

Abstract BACKGROUND Clinical trials have allowed the discovery of successful therapeutic intervention for cancer patients. The current number of cancer patients in the US has increased with an incidence of 442/100,000 population and yet with decreased yearly mortality rate. Spine metastatic disease occurs in approximately 90% of patients with cancer. The aim of this study is to analyze the current landscape of spine oncology trials to identify future opportunities. METHODS To assess active and ongoing clinical trials in the treatment of metastatic spinal disease, the authors queried https://clinicaltrials.gov/ under the searches “Spine Metastases” and “Spine Tumor.” Only clinical trials designated as “Recruiting” were included. Parametric and non-parametric statistical analysis was performed. RESULTS Our initial search yielded to 100 total studies; 18 clinical trials met entry criteria. Trial type was 16/18 therapeutic, 2/18 observational and trial design 6/18 (33%) randomized. All 18 trials were single center. Trials were were based in the United States (90%) and British Columbia, Canada. Across US geographical quadrants, a significant higher number of therapeutic trials was found in the South quadrant (12/16) compared to the other quadrants, (p&amp;lt; 0.001; Midwest: N=3/16, Northeast: N=1). The most common therapeutic focus included radiosurgery, followed by vertebral body augmentation and/or radiofrequency ablation, and laser interstitial thermal therapy (LITT). CONCLUSION Clinical trials are a cornerstone for the advancement oncological treatment. Our study shows that currently there is an ample opportunity to design clinical trials for our growing population of metastatic spine disease patients. Successful strategies to enhance the needed portfolio of spinal oncology trials, include focusing on including all US geographic quadrants. As new trials are designed, continued efforts devoted to data entry in national registry remains important.

Local Recurrence and Development of Spinal Cord Syndrome during Follow-Up after Surgical Treatment of Metastatic Spine Disease.

Surgical decompression (SD), with or without posterior stabilization followed by radiotherapy, is an established treatment for patients with metastatic spinal disease with epidural spinal cord compression (ESCC). This study aims to identify risk factors for occurrence of neurological compromise resulting from local recurrence. All patients who received surgical treatment for metastatic spinal disease at our center between 2011 and 2022 were included in this study. Cases were evaluated for tumor entity, surgical technique for decompression (decompression, hemilaminectomy, laminectomy, corpectomy) neurological deficits, grade of ESCC, time interval to radiotherapy, and perioperative complications. A total of 747 patients were included in the final analysis, with a follow-up of 296.8 days (95% CI (263.5, 330.1)). During the follow-up period, 7.5% of the patients developed spinal cord/cauda syndrome (SCS). Multivariate analysis revealed prolonged time (>35 d) to radiation therapy as a solitary risk factor (p < 0.001) for occurrence of SCS during follow-up. Surgical treatment of spinal metastatic disease improves patients' quality of life and Frankel grade, but radiation therapy needs to be scheduled within a time frame of a few weeks in order to reduce the risk of tumor-induced neurological compromise.

Treatment of Metastatic Spinal Disease; what the Radiologist needs to know.

Advancements in technology and multidisciplinary management have revolutionized the treatment of spinal metastases. Imaging plays a pivotal role in determining the treatment course for spinal metastases. This article aims to review the relevant imaging findings in spinal metastases from the perspective of the treating clinician, describe the various treatment options, and discuss factors influencing choice for each available treatment option. Cases that once required radical surgical resection or low-dose conventional external beam radiation therapy, or both, are now being managed with separation surgery, spine stereotactic radiosurgery/stereotactic body radiation therapy, or both, with decreased morbidity, improved local control, and more durable pain control. The primary focus in determining treatment choice is now on tumor control outcomes, treatment-related morbidity, and quality of life.

The Utility of 'Minimal Access and Separation Surgery' in the Management of Metastatic Spine Disease.

Retrospective cohort study. To compare outcomes of percutaneous pedicle screw fixation (PPSF) to open posterior stabilization (OPS) in spinal instability patients and minimal access separation surgery (MASS) to open posterior stabilization and decompression (OPSD) in metastatic spinal cord compression (MSCC) patients. We analysed patients who underwent surgery for thoracolumbar metastatic spine disease (MSD) from Jan 2011 to Oct 2017. Patients were divided into minimally invasive spine surgery (MISS) and open spine surgery (OSS) groups. Spinal instability patients were treated with PPSF/OPS with pedicle screws. MSCC patients were treated with MASS/OPSD. Outcomes measured included intraoperative blood loss, operative time, duration of hospital stay and ASIA-score improvement. Time to initiate radiotherapy and perioperative surgical/non-surgical complications was recorded. Propensity scoring adjustment analysis was utilised to address heterogenicity of histological tumour subtypes. Of 200 eligible patients, 61 underwent MISS and 139 underwent OSS for MSD. There was no significant difference in baseline characteristics between MISS and OSS groups. In the MISS group, 28 (45.9%) patients were treated for spinal instability and 33 (54.1%) patients were treated for MSCC. In the OSS group, 15 (10.8%) patients were treated for spinal instability alone and 124 (89.2%) were treated for MSCC. Patients who underwent PPSF had significantly lower blood loss (95mL vs 564mL; P < .001) and surgical complication rates(P < .05) with shorter length of stay approaching significance (6 vs 19days; P = .100) when compared to the OPS group. Patients who underwent MASS had significantly lower blood loss (602mL vs 1008mL) and shorter length of stay (10 vs 18days; P = .098) vs the OPSD group. This study demonstrates the benefits of PPSF and MASS over OPS and OPSD for the treatment of MSD with spinal instability and MSCC, respectively.

Percutaneous fixation for the treatment of metastatic spinal disease provides effective symptom palliation with low rates of hardware failure.

Background: The incidence of survival from metastatic spinal disease (MSD) continues to rise. However, open surgery for MSD is associated with significant perioperative morbidity, while minimally invasive percutaneous pedicle screw fixation (MIPPSF) offers reduced tissue trauma, less blood loss, and a reduction in complications. Lytic bone disease plus perioperative radiation further increase risk for instrument failure, especially in long construct MIPPSF. Here, we compared 6 short construct and 14 long construct outcomes for MIPPSF performed in MSD patients, including multiple myeloma (MM).Methods: For 20 patients undergoing MIPPSF for MSD, we evaluated disease type, location, the extent of surgery, outcomes, and survival rates. Statistical comparisons were performed between long-segment construct and short-segment construct patients utilizing Kaplan–Meier survival curves, Mann–Whitney U, and Chi-squared tests.Results: No instrument failure and comparable symptomatic relief were observed for both short and long MIPPSF constructs. However, long construct patients experienced; a higher incidence of postoperative complications, including screw loosening, but exhibited longer overall survivals (likely related to underlying type of MSD, with MM patients making up the largest portion of long construct patients).Conclusion: Long construct MIPPSF in MSD did not have increased risk of construct failure and offered effective symptomatic relief, including for MM patients, without introducing a greater risk construct instability.

168. Factors associated with the failure to meet 90-day estimated survival after the surgical treatment of spinal metastases

BACKGROUND CONTEXT Many prognostic scoring systems have been developed and provide estimated prognosis for surgical decision making in the treatment of vertebral metastatic disease. External validation studies have confirmed the diagnostic ability of these scoring systems to discriminate between various disease states and relative survival. However, analysis of the individual patient factors associated with misprognostication has not been completed and provides important insight into the failure of patients to meet an estimated prognosis. PURPOSE N/A STUDY DESIGN/SETTING N/A PATIENT SAMPLE N/A OUTCOME MEASURES N/A METHODS Preoperative prognostic scores were calculated for 90 patients undergoing operative treatment of metastatic spine disease using nine prevalent scoring systems including the Skeletal Oncology Research Group (SORG) Classic Algorithm, SORG Nomogram, original Tokuhashi, revised Tokuhashi, Tomita, original Bauer, modified Bauer, Katagiri, and van der Linden. The diagnostic accuracy of each scoring system at 90 days was evaluated using a receiver operating characteristic (ROC) model and the scoring system that demonstrated the highest accuracy was used to calculate an estimated 90-day survival for each individual patient. The actual survival of each patient was compared to estimated survival and the accuracy of each individual prognosis estimation was evaluated for correctness using a cutoff point of 0.5, which represents a 50% probability of survival at 90 days. The factors associated with incorrect estimated prognosis were then identified using a binary logistic regression model. RESULTS Among all scoring systems, the SORG nomogram demonstrated the highest accuracy at predicting 90-day survival with an AUC of 0.702. In 13 records, 90-day survival was overestimated (incorrectly classified records from probability 0.5-1.0) in which patients lived less than the estimated 90 days. Most misclassifications were optimistic, with a median estimated probability of 0.75 (total range 0.46-0.85). Both postoperative Karnofsky Performance Scale Index (KPS) and return to preoperative KPS level at 30 days post-operatively were found to be significant predictors of failure to meet 90-day predicted survival with an odds ratio of 51.3 (95% CI: 10.0-262.1, p: CONCLUSIONS Prognostic scoring systems provide clinicians with a preoperative estimation of a patients expected survival at various time points. It is shown here that failure to reach a functional status that allows for basic selfcare within 30 days of surgery, as evidenced by a KPS level greater than 40, is a significant predictor of failure to meet estimated survival. Clinicians should be aware of this and resources should be directed at maximizing physical rehabilitation and function specifically within the first 30 days after surgery, patients should be counseled accordingly, and further treatment decisions should also take this into account. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Surgical treatment of metastatic spine disease: an update on national trends and clinical outcomes from 2010 to 2014

BACKGROUND CONTEXTMetastatic spine disease (MSD) is becoming more prevalent as medical treatment for cancers advance and extend survival. More MSD patients are treated surgically to maintain neurological function, ambulation, and quality of life. PURPOSEThe purpose of this study was to use a large, nationally representative database to examine the trends, patient outcomes, and health-care resource utilization associated with surgical treatment of MSD. DESIGNThis was an epidemiologic study using national administrative data from the Nationwide Readmissions Database (NRD). PATIENT SAMPLEAll patients in the NRD from 2010 to 2014 who underwent spinal surgery were included in the study. OUTCOME MEASURESMortality, blood transfusion, complications, length of stay, cost, and discharge location during index hospitalization as well as hospital readmission and revision surgery within 90-days of surgery were analyzed. METHODSInternational Classification of Diseases, Ninth Revision, (ICD-9) codes was used to identify patients of interest within the NRD from 2010 to 2014. Patients were separated into two cohorts – those with MSD and those without. Trends for surgical treatment of MSD were assessed and outcomes measures for both cohorts were analyzed and compared. RESULTSThe number of surgical treatments for MSD increased from 6,007 in 2010 to 7,032 in 2014 (p-trend<.0001) which represented a 17.1% increase. During index hospitalization, MSD patients had an increased risk of mortality (odds ratio [OR]=3.22, 95% confidence interval [CI]: 2.85–3.63, p<.0001), blood transfusion (OR=2.93, 95% CI: 2.66–3.23, p<.0001), any complication (OR=1.24, 95% CI: 1.18–1.31, p<.0001), and discharge to skilled nursing facility (OR=1.51, 95% CI:1.41–1.61, p<.0001). MSD patients had longer average length of stay (13.05 vs. 4.56 days, p<.0001) and cost ($49,421.75 vs. $26,190.37, p<.0001) during index hospitalization. Furthermore, MSD patients had an increased risk of hospital readmission (OR=2.82, 95% CI: 2.68–2.96, p<.0001), readmission for surgical site infection (OR=2.38, 95% CI: 2.20–2.58, p<.0001), and readmission with neurologic deficits (OR=1.62, 95% CI: 1.27–2.06, p<.0001) despite a decreased risk of revision fusion (OR=0.71, 95% CI: 0.53–0.96, p=.026). CONCLUSIONSThe number of MSD patients who undergo surgical treatments is increasing. Not only do these patients have worse outcomes during index hospitalization, but they are also at an increased risk of hospital readmission for surgical site infection and neurologic complications. These findings stress the need for multidisciplinary perioperative treatment plans that mitigate risks and facilitate quick, effective recovery in these unique, at-risk patients.

Necessity of Bony Fusion After Surgical Treatment of Metastatic Spine Tumors.

The role of bony fusion in influencing patient outcome and surgical revision rates in the treatment of metastatic spine disease is poorly defined. The goals of this study were, therefore, to evaluate the effect of fusion on revision surgery as well as on overall survival (OS) and functional status in patients with metastatic disease of the spine. A retrospective cohort study of a prospective database at a major cancer center was conducted. A total of 25 patients who met the inclusion criteria from January 2010 to December 2015 were included. Functional status, patient and tumor characteristics, fusion status, and survival were analyzed, and regression analyses were done. Bony fusion was classified as either present (seen across a minimum of three levels and crossing the tumor site) or absent as evidenced through CT images at minimum of 1-year postoperatively. Twenty-five subjects with 28 surgical sites met the eligibility criteria to be included in this study cohort. Five surgical sites were found to have evidence of fusion on CT scans at 1 year after surgery, and 23 sites had no evidence of bridging fusion. No differences were found between the two groups in terms of OS, and ambulatory status (P > 0.10). Multivariate analysis did not reveal any specific factors affecting fusion. Mean follow-up was 23.7 months. The lack of bony fusion is not an independent predictor of the need for revision surgery. The lack of bony fusion in patients with metastatic disease of the spine does not appear to negatively affect their OS or their ambulatory status. A discussion of factors affecting fusion is complex, and there are other factors that may also play a role. Large multicenter trials are needed to corroborate the preliminary findings seen in this complex patient cohort.

Stereotactic Radiation Therapy (SBRT) Versus External Beam (EB) Radiation for Metastatic Spine Disease: Comparing Fracture Rates and Local Control

Abstract INTRODUCTION Stereotactic radiation therapy (SBRT) is often preferred to external beam (EB) radiation because it provides a higher radiation dose and reduces need for retreatment to the same site. Although SBRT is regarded as a viable option, there is no research comparing fracture rates and disease progression to EB radiation. METHODS Records from patients treated at our hospital for metastatic spine disease were retrospectively reviewed. Mortality, local disease progression (resulting in additional intervention or radiographic progression), and vertebral body fractures were compared between SBRT and EB radiation. A total of 96 and 213 patients were identified for SBRT and EB groups respectively. Multivariate regression identified the need to control for tumor histology, follow-up time (in months), and age at therapy. The patient-matched EB comparison group was made by matching SBRT cases on propensity scores for confounders. Matching resulted in 70 SBRT-EB cases. RESULTS Following the matching process, balance of the covariates (age at therapy, follow-up time, and primary tumor histology) was confirmed between groups (P = .136, P = .596 respectively and matched tumor histology). The SBRT group did not significantly differ in mortality rates and local disease progression compared to the EB group (P = .731, P = .847 respectively). However, the SBRT group did have a higher rate of vertebral body fracture: 14.2% compared to 4.2% in the EB group (P &lt; .01). Multivariate analysis was used to account for potentially confounding effects of dose using biologically equivalent doses calculated with a/ß of 10 (ie, BED10) for acute toxicity and 3 (ie, BED3) for late toxicity, but did not affect results. CONCLUSION The data suggest that receiving SBRT for the treatment of metastatic spine disease may increase risk for vertebral body fracture compared to EB treatment. There were no differences in local disease progression or mortality.

Treatment, complications, and outcomes of metastatic disease of the spine: from Patchell to PROMIS.

Spinal metastases are common in patients with cancer. As cancer treatments improve and these patients live longer, the number who present with metastatic spine disease will increase. Treatment strategies for these patients continues to evolve. In particular, since the prospective randomized controlled study in 2005 by Patchell et al. showed increased survival with decompressive surgical treatment of spinal metastases, there is a growing body of literature focusing on surgical management and complications of surgery for this disease. Surgery is often one component of a multimodal treatment approach with chemotherapy and radiation, which makes it difficult to parse the benefits of each individual treatment in outcome studies. Additionally, there has been more recent emphasis placed on patient-reported outcomes (PRO) after treatment for metastatic spine disease. In this review, we summarize treatments of metastatic spinal disease, possible perioperative complications, and validated tools used to assess outcomes for these patients.

Advances in personalized treatment of metastatic spine disease.

The spine is one of the most common sites of bony metastases, and its involvement leads to significant patient morbidity. Surgical management in these patients is aimed at improving quality of life and functional status throughout the course of the disease. Resection of metastases often leads to critical size bone defects, presenting a challenge to achieving adequate bone regeneration to fill the void. Current treatment options for repairing these defects are bone grafting and commercial bone cements; however, each has associated limitations. Additionally, tumor recurrence and tumor-induced bone loss make bone regeneration particularly difficult. Systemic therapeutic delivery, such as bisphosphonates, have become standard of care to combat bone loss despite unfavorable systemic side-effects and lack of local efficacy. Developments from tissue engineering have introduced novel materials with osteoinductive and osteoconductive properties which also act as structural support scaffolds for bone regeneration. These new materials can also act as a therapeutic reservoir to sustainably release drugs locally as an alternative to systemic therapy. In this review, we outline recent advancements in tissue engineering and the role of translational research in developing implants that can fully repair bone defects while also delivering local therapeutics to curb tumor recurrence and improve patient quality of life.

Outcomes and cost-minimization analysis of cement spacers versus expandable cages for posterior-only reconstruction of metastatic spine corpectomies.

Reconstruction of the thoracolumbar spine after tumor corpectomy can be accomplished using either an expandable metallic cage (EC) or a polymethylmethacrylate (PMMA) cement spacer. Few studies have compared the relative successes between these two forms of reconstructions in the management of metastatic spine disease (MSD). The purpose of this study was to compare both the outcomes and costs of EC and PMMA spacers in the treatment of MSD. We hypothesized that the rate of complications and revision surgery when using PMMA spacers to reconstruct the spine after corpectomy for MSD would be equivalent to use of an EC, with lower implant and operating room (OR) costs. A single surgeon performed 65 vertebral corpectomies for MSD requiring anterior column reconstruction from 2007-2014. Charts were retrospectively reviewed and no patients were excluded. All resections were single-stage resections/reconstructions of the vertebral body through a posterior-only approach. Outcomes evaluated included perioperative complications, intraoperative time, postoperative survival, subsequent reoperations, and changes in radiographic spinal alignment. Thirty-six patients were treated with PMMA spacers; 29 were treated with EC. Baseline age, BMI, comorbidities, and disease severity as measured by Tokuhashi scores were equivalent between treatment groups. The cohorts had no significant differences in operative complications, blood loss, postoperative survival, number of subsequent reoperations, or changes in radiographic alignment. PMMA patients had a significantly shorter mean operative duration (328.6 vs. 241.1 min, P<0.001). Institutional implant cost savings were $4,355 favoring the PMMA cohort ($75 for cement vs. $5,000 for cage). Mean OR time savings were calculated to be $2,001 less for the PMMA cohort. Total cost minimization per PMMA case was thus $6,356, which was robust in 2-way sensitivity analyses varying both implant costs and time costs by 30%. In the largest series of posterior-only corpectomies for MSD reconstructed with PMMA, PMMA intervertebral spacers provided equivalent stability and longevity to EC, at a fraction of the cost. PMMA showed excellent durability while minimizing costs by $6,356 per case, an important consideration as reimbursement pressures increasingly influence surgical decision making.

Predicting survival for metastatic spine disease: a comparison of nine scoring systems

Background ContextDespite advances in spinal oncology, research in patient-based prognostic calculators for metastatic spine disease is lacking. Much of the literature in this area investigates the general predictive accuracy of scoring systems in heterogeneous populations, with few studies considering the accuracy of scoring systems based on patient specifics such as type of primary tumor. PurposeThe aim of the present study was to compare the ability of widespread scoring systems to estimate both overall survival at various time points and tumor-specific survival for patients undergoing surgical treatment for metastatic spine disease in order to provide surgeons with information to determine the most appropriate scoring system for a specific patient and timeline. Study DesignThis is a retrospective study. Patient SamplePatients who underwent surgical resection for metastatic spine disease at a single institution were included. Outcome MeasuresAreas under the receiver operating characteristic curves were generated from comparison of actual survival of patients and survival as predicted by application of prevalent scoring systems. MethodsA preoperative score for all 176 patients was retrospectively calculated utilizing the Skeletal Oncology Research Group (SORG) Classic Scoring Algorithm, SORG Nomogram, original Tokuhashi, revised Tokuhashi, Tomita, original Bauer, modified Bauer, Katagiri, and van der Linden scoring systems. Univariate and multivariate Cox proportional hazard models were constructed to assess the association of patient variables with survival. Receiver operating characteristic analysis modeling was utilized to quantify the accuracy of each test at different end points and for different primary tumor subgroups. No funds were received in support of this work. The authors have no conflicts of interest to disclose. ResultsAmong all patients surgically treated for metastatic spine disease, the SORG Nomogram demonstrated the highest accuracy at predicting 30-day (area under the curve [AUC] 0.81) and 90-day (AUC 0.70) survival after surgery. The original Tokuhashi was the most accurate at predicting 365-day survival (AUC 0.78). Multivariate analysis demonstrated multiple preoperative factors strongly associated with survival after surgery for spinal metastasis. The accuracy of each scoring system in determining survival probability relative to primary tumor etiology and time elapsed since surgery was assessed. ConclusionsAmong the nine scoring systems assessed, the present study determined the most accurate scoring system for short-term (30-day), intermediate (90-day), and long-term (365-day) survival, relative to primary tumor etiology. The findings of the present study may be utilized by surgeons in a personalized effort to select the most appropriate scoring system for a given patient.

Hardware failure in patients with metastatic cancer to the spine

BackgroundThe spine is the most common site of skeletal metastases, affecting approximately 30% of individuals with cancer. The aim of surgical treatment for metastatic spine disease is generally palliative to address pain and/or neurologic compromise, significantly improving patients’ quality of life. Patients with metastatic spine disease, however, represent a vulnerable cohort and may have comorbidities or previous treatments that impair the structural integrity of spinal hardware. As such, identifying factors that may contribute to hardware failure is an essential component in treating individuals with metastatic spine disease. ObjectiveThe aim of this study was to identify pre-operative risk factors associated with hardware failure in patients undergoing surgical treatment for metastatic spine disease. MethodsA retrospective cohort study was conducted to include patients surgically treated for metastatic spine tumors between 2003 and 2013, at a single institution. A univariate analysis was initially performed to identify associated factors. Any associated factor with a p-value <0.20 was included in the multivariate analysis. Results3 patients (1.9%), of the 159 patients included in the study, had failure of the spine instrumentation. 1 patient had metastatic prostate cancer, and 2 had metastatic breast cancer. Patient demographics, co-morbidities, tumor location, and primary tumor etiology were not found to be statistically significant, with respect to hardware failure. Predictive factors included in the multivariate model were other bone metastasis, visceral metastasis, brain metastasis, Modified Rankin scale, previous systemic chemotherapy, previous radiation to the spine, and mean survival. Previous radiation to the spine was the only factor to be significantly associated (p=0.029), present in all three patients with hardware failure. Of note, there was a trend indicating that patients with longer life expectancies were more likely to experience hardware failure (mean survival of 16.7months in non-failure cohort vs. 33months in failure cohort), though this did not achieve statistical significance due to the limited sample size of patients with hardware failure. ConclusionHardware failure is a risk for all patients who undergo instrumentation following resection for metastatic spine tumors. This study identified that pre-operative radiation may increase the risk for hardware failure in this population.

Percutaneous Spinal Ablation in a Sheep Model: Protective Capacity of an Intact Cortex, Correlation of Ablation Parameters with Ablation Zone Size, and Correlation of Postablation MRI and Pathologic Findings.

Despite the growing use of percutaneous ablation therapy for the treatment of metastatic spine disease, several issues have yet to be fully addressed. Our aims were to determine whether the vertebral body cortex protects against ablation-induced spinal cord injury; correlate radiofrequency, cryo-, and microwave ablation parameters with resulting spinal ablation zone dimensions and describe normal spinal marrow postablation changes on MR imaging. Ten thoracolumbar vertebrae in 3 sheep were treated with radiofrequency ablation, cryoablation, or microwave ablation under fluoroscopic guidance. Technique parameters were chosen to produce ablation zones that exceeded the volume of the vertebral bodies in sheep 1 and were confined to the vertebrae in sheep 2 and 3. Expected ablation zone dimensions were based on data provided by the device manufacturers. Postablation MR imaging was performed at 48 hours (sheep 1) or 7 days (sheep 2 and 3). In sheep 1, cryoablation and microwave ablations extended into the spinal canal and caused histologically confirmed neurologic injury, but radiofrequency ablation did not. The mean difference between the lengths of the radiofrequency ablation zone dimensions measured on gross pathology compared with those expected was 9.6 ± 4.1 mm. The gross pathologic cryo- and microwave ablation zone dimensions were within 1 mm of those expected. All modalities produced a nonenhancing ablation zone with a rim of enhancement, corresponding histologically to marrow necrosis and hemorrhagic congestion. An intact cortex appears to protect against radiofrequency ablation-induced spinal cord injury, but not against non-impedance-based modalities. Ablation dimensions produced by microwave and cryoablation are similar to those expected, while radiofrequency ablation dimensions are smaller. Ablation of normal marrow produces a rim of enhancement at the margin of the ablation zone on MR imaging.

Most efficient questionnaires to measure quality of life, physical function, and pain in patients with metastatic spine disease: a cross-sectional prospective survey study

Background ContextAssessing quality of life, functional outcome, and pain has become important in assessing the effectiveness of treatment for metastatic spine disease. Many questionnaires are able to measure these outcomes; few are validated in patients with metastatic spine disease. As a result, there is no consensus on the ideal questionnaire to use in these patients. PurposeOur study aim was to assess whether certain questionnaires measuring quality of life, functional outcome, and pain (1) correlated with each other, (2) measured the construct they claim to measure, (3) had good coverage—floor and ceiling effects, (4) were reliable, and (5) whether there were differences in completion time between them. DesignThis is a prospective cross-sectional survey study from three outpatient clinics (two orthopedic oncology clinics and one neurosurgery clinic) from two affiliated tertiary hospital care centers. Patient SampleWe included 100 consecutive patients with metastatic spine disease between July 2014 and February 2016. We excluded non–English-speaking patients. Outcome MeasuresThe following questionnaires were given in random order: Oswestry Disability Index (ODI) or Neck Disability Index (NDI), Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function, PROMIS Pain Intensity, EuroQol-5 Dimensions (EQ-5D), and the Spine Oncology Study Group Outcome Questionnaire (SOSG-OQ). MethodsWe used exploratory factor analysis—correlating questionnaires with an underlying mathematically derived trait—to assess if questionnaires measured the same concept. Coverage was assessed by floor and ceiling effects, and reliability was assessed by standard error of measurement as a function of ability. Differences in completion times were tested using the Friedman test. ResultsQuestionnaires measured the construct they were developed for, as demonstrated with high correlations (>0.7) with the underlying trait. A floor effect was present in the PROMIS Pain Intensity (7.0%), ODI or NDI (4.0%), and the PROMIS Physical Function (1.0%) questionnaires. A ceiling effect was present in the EQ-5D questionnaire (6.0%). The SOSG-OQ had no floor or ceiling effect. The PROMIS Physical Function and PROMIS Pain Intensity proved to be the most reliable, whereas the EQ-5D was the least reliable. Completion time differed among questionnaires (p<.001) and was shortest for the PROMIS Pain Intensity (median 24 seconds) and PROMIS Physical Function (median 42 seconds). ConclusionsIn patients with metastatic spine disease, we recommend the SOSG-OQ for measuring quality of life, the PROMIS Physical Function for measuring physical function, and the PROMIS Pain Intensity for measuring pain.

Perioperative Complications of Spinal Metastases Surgery.

The incidence of symptomatic spinal metastasis has increased due to treatment improvements and longer patient survival. More patients with spinal tumors are choosing operative treatment with an associated increased rate of perioperative complications. Operative metastatic disease treatment complication rates have also increased with overall rates ranging from 5.3% to 76.20%. The common surgical-related complications are iatrogenic dural injury and wound complications. The most common postoperative medical complications are delirium, pneumonia, and deep vein thrombosis. Risk factors for perioperative complications after spinal metastatic surgery include older age, multilevel of spinal metastases, preoperative irradiation, low preoperative Karnofsky Performance Score (10-40) and multiple comorbidities. Charlson Comorbidity Index and New England Spinal Metastasis Score were significant predictor of 30-day complications. The reoperation rate is 10.7%, and the reoperation is most commonly performed in the same admission. In addition, the 30-day mortality rate in this patient population is ∼7% (0.9%-13%) and is influenced by the type of cancer, disease burden, and patient comorbidities. We reviewed the prevalence and risk factors of common perioperative complications that occur with surgical treatment of metastatic spine disease, in an effort to guide the spine surgeon in anticipating and potentially avoiding these complications.

When Less Is More: The indications for MIS Techniques and Separation Surgery in Metastatic Spine Disease.

Systematic review. The aim of this study was to review the techniques, indications, and outcomes of minimally invasive surgery (MIS) and separation surgery with subsequent radiosurgery in the treatment of patients with metastatic spine disease. The utilization of MIS techniques in patients with spine metastases is a growing area within spinal oncology. Separation surgery represents a novel paradigm where radiosurgery provides long-term control after tumor is surgically separated from the neural elements. PubMed, Embase, and CINAHL databases were systematically queried for literature reporting MIS techniques or separation surgery in patients with metastatic spine disease. PRISMA guidelines were followed. Of the initial 983 articles found, 29 met inclusion criteria. Twenty-five articles discussed MIS techniques and were grouped according to the primary objective: percutaneous stabilization (8), tubular retractors (4), mini-open approach (8), and thoracoscopy/endoscopy (5). The remaining 4 studies reported separation surgery. Indications were similar across all studies and included patients with instability, refractory pain, or neurologic compromise. Intraoperative variables, outcomes, and complications were similar in MIS studies compared to traditional approaches, and some MIS studies showed a statistically significant improvement in outcomes. Studies of mini-open techniques had the strongest evidence for superiority. Low-quality evidence currently exists for MIS techniques and separation surgery in the treatment of metastatic spine disease. Given the early promising results, the next iteration of research should include higher-quality studies with sufficient power, and will be able to provide higher-level evidence on the outcomes of MIS approaches and separation surgery. N/A.

Percutaneous Minimally Invasive Techniques in the Treatment of Spinal Metastases.

Spinal metastases are a common and morbid condition in America. Of the 1.6 million new cases of cancer estimated to be diagnosed in the USA in 2015, approximately 5-10% will develop spinal metastases. This number is expected to increase as the life expectancy of cancer patients increases. Patients with osteolytic spinal metastases experience severe and often debilitating pain, which significantly reduces quality of life. Due to the morbidity of open surgery, particularly in oncologic patients, the treatment paradigm has shifted towards minimally invasive therapy. The advent and evolution of percutaneous treatments of spinal metastases has shown progressive success in reducing pain, improving function, and providing mechanical stability. There are various currently available interventions including vertebroplasty, vertebral augmentation, and coblation and radiofrequency ablation systems. For more complex spinal metastases, combined treatments including vertebral augmentation in conjunction with radiofrequency ablation, external beam radiation, and the novel treatment of intraoperative radiotherapy are also available. Ultimately, the goal of treatment in this patient population is palliative with the intention of improving the remaining quality of life. There is no established algorithm or specific technique that has proved best for the many variations of vertebral compression fractures (VCFs), so treatment tends to be dependent on the operator and/or based on institution preference or bias. Each technique provides its own unique value in the various types of metastatic VCFs encountered, and understanding the uses, advantages, and safety profile of each specific treatment is imperative in providing the best patient care. Percutaneous treatment of metastatic spinal disease is an excellent alternative to medical and surgical management in carefully selected patients. We believe that a multidisciplinary approach and combination therapy allows for optimal pain reduction and improvement of function.