Disparities in Primary Spinal Osseous Malignant Bone Tumor Survival by Medicaid Status: A National Population-Based Risk Analysis.

BACKGROUND: The impact of Medicaid status on survival outcomes of patients with spinal primary malignant bone tumors (sPMBT) has not been investigated. METHODS: Using the SEER-Medicaid database, adults diagnosed between 2006 and 2013 with sPMBT including chordoma, osteosarcoma, chondrosarcoma, Ewing sarcoma, or malignant giant cell tumor (GCT) were studied. Five-year survival analysis was performed using the Kaplan-Meier method. Adjusted survival analysis was performed using Cox proportional-hazards regression controlling for age, sex, marital status, cancer stage, poverty level, vertebral versus sacral location, geography, rurality, tumor diameter, tumor grade, tumor histology, and therapy. RESULTS: A total of 572 patients with sPMBT (Medicaid: 59, non-Medicaid: 513) were identified. Medicaid patients were more likely to be younger (P < 0.001), Black (P < 0.001), live in high poverty neighborhoods (P = 0.006), have distant metastases at diagnosis (P < 0.001), and less likely to receive surgery (P = 0.006). The 5-year survival rate was 65.7% (chondrosarcoma: 70.0%, chordoma: 91.5%, Ewing sarcoma: 44.6%, GCT: 90.0%, osteosarcoma: 34.2%). Medicaid patients had significantly worse 5-year survival than non-Medicaid patients (52.0% vs. 67.2%, P = 0.02). Minority individuals on Medicaid were associated with an increased risk of cancer-specific mortality compared with White non-Medicaid patients (adjusted hazard ratio [aHR] = 2.51, [95% CI 1.18-5.35], P = 0.017). Among Medicaid patients, those who received surgery had significantly better survival than those who did not (64.5% vs. 30.6%, P = 0.001). For all patients, not receiving surgery (aHR = 1.90 [1.23-2.95], P = 0.004) and tumor diameter >50 mm (aHR=1.89 [1.10-3.25], P = 0.023) were associated with an increased risk of mortality. CONCLUSIONS: Medicaid patients may be less likely to receive surgery and suffer from poorer survival. These disparities may be especially prominent among minorities.

Management of Spinal Lymphomas: Spinal Instability Assessment Using the Spinal Instability Neoplastic Score and a Proposed Treatment Algorithm.

AIM: To propose a treatment algorithm, and to assess spinal instability in patients diagnosed with spinal lymphoma. MATERIAL AND METHODS: Demographics, symptoms, tumor level and location, and presence of spinal instability were reviewed in 22 patients with spinal lymphomas. Each patient's neurological state was reviewed using the American Spinal Injury Association and modified McCormick scale scores, and spinal instability was assessed using the Spinal Instability Neoplastic Score (SINS). RESULTS: Initially, percutaneous biopsy was performed in 16 patients, and open biopsy was performed in 6 patients. Eight of the patients who underwent percutaneous biopsy were followed up with hematological examination alone, as they had no additional complaints. The SINS was used to evaluate the presence of spinal instability, and the type of surgery to be performed was decided accordingly. In the second surgery, decompression and stabilization were performed in 5 of the remaining 8 patients, and only decompression was performed in 3 of them. Neurological improvement was observed in 6 of 7 patients with acute neurological deficit. CONCLUSION: Percutaneous biopsy for tissue diagnosis is the first step in the management of spinal lymphomas. Patients without neurological deficit should be referred for hematological examination. Those with acute neurological deficit require emergency surgery, and those with chronic symptoms must undergo operation for decompression and/or stabilization. This study confirmed the safety of the SINS in the evaluation of spinal instability in spinal lymphoma cases.

Development and Assessment of a Predictive Score for Vertebral Compression Fracture After Stereotactic Body Radiation Therapy for Spinal Metastases.

IMPORTANCE: Vertebral compression fracture (VCF) is a potential adverse effect following treatment with stereotactic body radiation therapy (SBRT) for spinal metastases. OBJECTIVE: To develop and assess a risk stratification model for VCF after SBRT. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study conducted at a high-volume referral center included 331 patients who had undergone 464 spine SBRT treatments from December 2007 through October 2019. Data analysis was conducted from November 1, 2020, to August 17, 2021. Exclusions included proton therapy, prior surgical intervention, vertebroplasty, or missing data. EXPOSURES: One and 3 fraction spine SBRT treatments were most commonly delivered. Single-fraction treatments generally involved prescribed doses of 16 to 24 Gy (median, 20 Gy; range, 16-30 Gy) to gross disease compared with multifraction treatment that delivered a median of 30 Gy (range, 21-50 Gy). MAIN OUTCOMES AND MEASURES: The VCF and radiography components of the spinal instability neoplastic score were determined by a radiologist. Recursive partitioning analysis was conducted using separate training (70%), internal validation (15%), and test (15%) sets. The log-rank test was the criterion for node splitting. RESULTS: Of the 331 participants, 88 were women (27%), and the mean (IQR) age was 63 (59-72) years. With a median follow-up of 21 months (IQR, 11-39 months), we identified 84 VCFs (18%), including 65 (77%) de novo and 19 (23%) progressive fractures. There was a median of 9 months (IQR, 3-21 months) to developing a VCF. From 15 candidate variables, 6 were identified using the backward selection method, feature importance testing, and a correlation heatmap. Four were selected via recursive partitioning analysis: epidural tumor extension, lumbar location, gross tumor volume of more than 10 cc, and a spinal instability neoplastic score of more than 6. One point was assigned to each variable, and the resulting multivariable Cox model had a concordance of 0.760. The hazard ratio per 1-point increase for VCF was 1.93 (95% CI, 1.62-2.30; P < .001). The cumulative incidence of VCF at 2 years (with death as a competing risk) was 6.7% (95% CI, 4.2%-10.7%) for low-risk (score, 0-1; 273 [58.3%]), 17.0% (95% CI, 10.8%-26.7%) for intermediate-risk (score, 2; 99 [21.3%]), and 35.4% (95% CI, 26.7%-46.9%) for high-risk cases (score, 3-4; 92 [19.8%]) (P < .001). Similar results were observed for freedom from VCF using stratification. CONCLUSIONS AND RELEVANCE: The results of this cohort study identify a subgroup of patients with high risk for VCF following treatment with SBRT who may potentially benefit from undergoing prophylactic spinal stabilization or vertebroplasty.

Spine metastasis in patients with prostate cancer: Survival prognosis assessment.

BACKGROUND: Patients presenting spine metastasis (SpM) from prostate cancer (PC) form a heterogeneous population, through this study, we aimed to clarify and update their prognostic assessment. METHODS: The patient data used in this study was obtained from a French national multicenter database of patients treated for PC with SpM between 2014 and 2017. A total of 72 patients and 365 SpM cases were diagnosed. RESULTS: The median overall survival time for all patients following the event of SpM was 28.8 months. First, we identified three significant survival prognostic factors of PC patients with SpM: good Eastern Cooperative Oncology Group/World Health Organization personnel status (Status 0 hazard ratio [HR]: 0.031, 95% confidence interval [CI]: 0.008-0.127; p < .0001) or (Status 1 HR: 0.163, 95% CI: 0.068-0.393; p < .0001) and SpM radiotherapy (HR: 2.923, 95% CI: 1.059-8.069; p < .0001). Secondly, the presence of osteolytic lesions of the spine (vs. osteoblastic) was found to represent an independent prognosis factor for longer survival [HR: 0.424, 95% CI: 0.216-0.830; p = .01]. Other factors including the number of SpM, surgery, extraspinal metastasis, synchrone metastasis, metastasis-free survival, and SpM recurrence were not identified as being prognostically relevant to the survival of patients with PC. CONCLUSION: Survival and our ability to estimate it in patients presenting PC with SpM have improved significantly. Therefore, we advocate the relevance of updating SpM prognostic scoring algorithms by incorporating data regarding the timeline of PC as well as the presence of osteolytic SpM to conceive treatments that are adapted to each patient.

Improvement of metallic artifacts in computed tomography in the absence of artifact reduction algorithms for spinal treatment planning applications.

AIM OF STUDY: The goal of this research was to investigate if application of optimized imaging parameters, recommended in literature, would be effective in producing the image quality required for treatment planning of spinal radiation fields with metallic implants. MATERIALS AND METHODS: CT images from an anthropomorphic torso phantom with and without spinal implants were acquired using different imaging protocols: raising kVp and mAs, reducing the pitch and applying an extended CT scale (ECTS) technique. Profiles of CT number (CT#) were produced using DICOM data of each image. The effect of artifact on dose calculation accuracy was investigated using the image data in the absence of implant as a reference and the recommended electron density tolerance levels (Δρe). RESULTS: Raising the kVp was the only method that produced improvement to some degree in CT# in artifact regions. Application of ECTS improved CT# values only for metal. CONCLUSIONS: Although raising the kVp was effective in reducing metallic artifact, the significance of this effect on Δρe values in corrected images depends on the required tolerance for treatment planning dose calculation accuracy. ECTS method was only successful in correcting the CT number range in the metal. Although, application of ECTS method did not have any effect on artifact regions, its use is necessary in order to improve delineation of metal and accuracy of attenuation calculations in metal, provided that the treatment planning system can use an extended CT# calibration curve. Also, for Monte Carlo calculations using patient's images, ECTS-post-processed-CT images improve dose calculation accuracy for impure metals.

A two-step risk assessment method for radiofrequency ablations of spine metastases.

BACKGROUND: Spine metastases (MTS) can be treated via Radiofrequency Ablation (RFA) electrodes. To bring these electrodes into vertebral MTS, pathways have to be created. This can be done via transpedicular hammering or drilling. However, this is challenging due to spatial constraints, and because MTS can alter bone density considerably. METHOD: In this work a two-step method is presented that intends to offer cognitive and physical assistance. Step 1 comprises two visualization methods that depict safety margins between and in risk structures. For Step 2, the correlation between Hounsfield Units (HUs) and drilling forces was analyzed to support manual and robot-assisted RFAs. RESULTS: In-depth descriptions of two clinical cases and detailed feedback from the local clinic of neuroradiology are used to present the capabilities of the proposed method. Furthermore, a stiffness criterion is presented to predict drilling force changes from the local distribution and homogeneity of HUs with an inaccuracy of less than 1 mm. CONCLUSIONS: The combination of visualization and drilling force prediction shows potential to support manual and robot-assisted spine RFAs. However, limitations have to be addressed in the future. For example, it has to be carefully evaluated to which extent the proposed method can speed up the planning process and increase intervention safety.

Assessment and Management of Patients With Metastatic Spinal Cord Compression: A Multidisciplinary Review.

PURPOSE: Metastatic spinal cord compression (MSCC) can be a catastrophic manifestation of advanced cancer that causes immobilizing pain and significant neurologic impairment. Oncologists can protect their patients by having a high index of suspicion for MSCC when patients present with new or worsening back pain before motor, sensory, bowel, or bladder deficits develop. We provide an updated, evidence-based narrative review of the presentation, diagnosis, and treatment of MSCC. METHODS: This narrative review was conducted by searching MEDLINE and Cochrane Database of Systematic Reviews for relevant literature on the presentation, diagnosis, and treatment of patients with MSCC. The article addresses the key elements of MSCC management germane to the medical oncologist, with special attention given to pain and symptom management, decision making with regard to surgery and radiation therapy, the importance of rehabilitative care, and the value of a multidisciplinary approach. RESULTS: Magnetic resonance imaging of the entire spine is recommended for the diagnosis of MSCC. Treatment includes glucocorticoid therapy, pain management, radiation therapy with or without surgery, and specialized rehabilitation. When formulating a treatment plan, clinicians should consider the patient's care goals and psychosocial needs. CONCLUSION: Prompt diagnosis and treatment of MSCC can reduce pain and prevent irreversible functional loss. Regular collaboration among multidisciplinary providers may streamline care and enhance achievement of treatment goals.

Relationship between tumor volume and quantitative values calculated using two-dimensional bone scan images.

The bone scan index (BSI) is calculated from a whole-body bone scan image; it shows the tumor burden in bone as a percentage of total skeletal mass. It has been used to determine the prognosis and to assess treatment effects; however, little has been reported on whether the BSI calculated using a two-dimensional image can accurately evaluate the three-dimensional spread in tumor volume. We investigated the relationship between tumor volume and BSI using Monte Carlo simulation (MCS). We simulated a gamma camera and constructed a voxel phantom based on an anthropomorphic phantom computed tomography (CT) image and gamma rays emitted from each part according to technetium-99m-labeled methylene diphosphonate (99mTc-MDP) uptake (bone 1, soft tissue 0.2, tumor 2-32). We constructed bone scan images from the obtained counts and analyzed them using the BSI calculation software. The BSI increased with increased tumor uptake (two- to 32-fold). However, there was not always a significant difference between change in BSI and tumor uptake of eight times or greater than that of bone. When BSI was calculated with a tumor having an uptake of four-to-eight times higher than that of bone, the BSI was consistent with tumor volume, but decreased to about half the tumor volume when tumors were in the thoracic spine (Th-spine) segment. The BSI can be a good indicator of tumor volume in most segments, even though it is affected by the tumor's 99mTc-MDP uptake. Nevertheless, values calculated from the Th-spine should be interpreted carefully.

The spine instability neoplastic score (SINS) in the assessment of response to radiotherapy for bone metastases.

BACKGROUND: Vertebral metastases are often causing pain and spine instability. Radiotherapy is of significant benefit for painful spine metastases but the response can be very variable. The spine instability neoplastic score (SINS) is a recent classification system for diagnosis of spinal instability caused by vertebral metastases. We analysed the degree of pain relief, the need of drug therapy and the imaging features and the SINS before and after radiotherapy. In particular, we investigated the possible correlation of spine instability defined by pre-treatment SINS with pretreatment pain and with response to radiotherapy. MATERIAL/METHODS: This study included 121 patients with spine metastases treated with palliative 3D conformal radiotherapy. Pain "at rest" and "breakthrough pain", need for drug therapy in terms of "anti-inflammatory", "weak opioid", "strong opioid", imaging studies and SINS were assessed before and after radiotherapy. Statistical analysis was performed by the correlation coefficient of Spearman and Kruskal-Wallis test. RESULTS: Pain relief after radiotherapy was observed in 50.4 and 57.8% of patients in terms of pain at rest and breakthrough pain, respectively. The correlation between pain before radiotherapy and SINS was not statistically significant for both pain at rest (p = 0.4) and breakthrough pain (p = 0.49). The correlation between pain response after radiotherapy and SINS was statistically significant for both pain at rest (p = 0.007) and breakthrough pain (p = 0.047). DISCUSSION/CONCLUSION: The degree of instability, classified according to SINS, resulted to be predictive factor for pain response after radiotherapy. SINS might become a valid tool to identify those patients who can benefit the most from radiotherapy.

[Comprehensive assessment of the outcomes of surgical treatment of patients with metastatic spinal cord injuries].

INTRODUCTION: Every year the number of cancer patients increases due to increased life expectancy. According to various sources, metastases in the spine are found during autopsy in 30-90% of patients with a history of cancer. So far, there have been no full-scale studies of the quality of life of patients with various metastatic tumors of the spine who underwent surgical treatment in Russian literature. The main objective of this study was to demonstrate the need for implementing the comprehensive treatment of patients with metastases in the spine and target setting as the main tool to identify the factors that adversely affect the patients' quality of life. MATERIAL AND METHODS: The quality of life of 56 patients aged 16 to 81 years was assessed, including 26 males and 30 females. Twenty-six patients underwent surgical treatment between 2002 and 2009, and thirty patients underwent surgical treatment between 2009 and 2014. Kidney cancer was a primary disease in 30.3% of patients, multiple myeloma was a primary disease in 23.1% of cases, and the primary source of a tumor was not identified in cancer screening in 10.5% of cases. There were also isolated cases of melanoma, thymoma, metastases of tumors of the gastrointestinal tract, uterus, ovary, lung, prostate, pancreas, and the thyroid gland, which on the average amounted to 3.5% (1.8 to 7.14%). The quality of life of patients was studied using the EORTC QLQ C30 scale. The patients were surveyed prior to the surgery and then 1, 3, 6 and 12 months after surgical treatment during 1 year or until death. Preoperative and postoperative contrast-enhanced SCT and MRI examinations were used to control the extent of decompression of neural structures. RESULTS: On the basis of these findings, the authors identified the main factors affecting the quality of life of patients and formulated a range of treatment goals for patients with metastases in the spine. CONCLUSION: Surgical treatment has a positive effect on the quality of life of patients with metastases in the spine. However, it is not a key factor in the context of survival rate of these patients. Therefore, a decision on the possibility and necessity of surgical treatment should be taken in cooperation with the patient and oncologists of different specialties.

A systematic review of evidence on malignant spinal metastases: natural history and technologies for identifying patients at high risk of vertebral fracture and spinal cord compression.

BACKGROUND: Spinal metastases can lead to significant morbidity and reduction in quality of life due to spinal cord compression (SCC). Between 5% and 20% of patients with spinal metastases develop metastatic spinal cord compression during the course of their disease. An early study estimated average survival for patients with SCC to be between 3 and 7 months, with a 36% probability of survival to 12 months. An understanding of the natural history and early diagnosis of spinal metastases and prediction of collapse of the metastatic vertebrae are important. OBJECTIVES: To undertake a systematic review to examine the natural history of metastatic spinal lesions and to identify patients at high risk of vertebral fracture and SCC. DATA SOURCES: The search strategy covered the concepts of metastasis, the spine and adults. Searches were undertaken from inception to June 2011 in 13 electronic databases [MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; EMBASE; Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials (CENTRAL); Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database (NHS EED), HTA databases (NHS Centre for Reviews and Dissemination); Science Citation Index and Conference Proceedings (Web of Science); UK Clinical Research Network (UKCRN) Portfolio Database; Current Controlled Trials; ClinicalTrials.gov]. REVIEW METHODS: Titles and abstracts of retrieved studies were assessed by two reviewers independently. Disagreement was resolved by consensus agreement. Full data were extracted independently by one reviewer. All included studies were reviewed by a second researcher with disagreements resolved by discussion. A quality assessment instrument was used to assess bias in six domains: study population, attrition, prognostic factor measurement, outcome measurement, confounding measurement and account, and analysis. Data were tabulated and discussed in a narrative review. Each tumour type was looked at separately. RESULTS: In all, 2425 potentially relevant articles were identified, of which 31 met the inclusion criteria. No study examined natural history alone. Seventeen studies reported retrospective data, 10 were prospective studies, and three were other study designs. There was one systematic review. There were no randomised controlled trials (RCTs). Approximately 5782 participants were included. Sample sizes ranged from 41 to 859. The age of participants ranged between 7 and 92 years. Types of cancers reported on were lung alone (n= 3), prostate alone (n= 6), breast alone (n= 7), mixed cancers (n= 13) and unclear (n= 1). A total of 93 prognostic factors were identified as potentially significant in predicting risk of SCC or collapse. Overall findings indicated that the more spinal metastases present and the longer a patient was at risk, the greater the reported likelihood of development of SCC and collapse. There was an increased risk of developing SCC if a cancer had already spread to the bones. In the prostate cancer studies, tumour grade, metastatic load and time on hormone therapy were associated with increased risk of SCC. In one study, risk of SCC before death was 24%, and 2.37 times greater with a Gleason score ≥ 7 than with a score of < 7 (p= 0.003). Other research found that patients with six or more bone lesions were at greater risk of SCC than those with fewer than six lesions [odds ratio (OR) 2.9, 95% confidence interval (CI) 1.012 to 8.35, p= 0.047]. For breast cancer patients who received a computerised tomography (CT) scan for suspected SCC, multiple logistic regression in one study identified four independent variables predictive of a positive test: bone metastases ≥ 2 years (OR 3.0 95% CI 1.2 to 7.6; p= 0.02); metastatic disease at initial diagnosis (OR 3.4, 95% CI 1.0 to 11.4; p= 0.05); objective weakness (OR 3.8, 95% CI 1.5 to 9.5; p= 0.005); and vertebral compression fracture on spine radiograph (OR 2.6, 95% CI 1.0 to 6.5; p= 0.05). A further study on mixed cancers, among patients who received surgery for SCC, reported that vertebral body compression fractures were associated with presurgery chemotherapy (OR 2.283, 95% CI 1.064 to 4.898; p= 0.03), cancer type [primary breast cancer (OR 4.179, 95% CI 1.457 to 11.983; p= 0.008)], thoracic involvement (OR 3.505, 95% CI 1.343 to 9.143; p= 0.01) and anterior cord compression (OR 3.213, 95% CI 1.416 to 7.293; p= 0.005). LIMITATIONS: Many of the included studies provided limited information about patient populations and selection criteria and they varied in methodological quality, rigour and transparency. Several studies identified type of cancer (e.g. breast, lung or prostate cancer) as a significant factor in predicting SCC, but it remains difficult to determine the risk differential partly because of residual bias. Consideration of quantitative results from the studies does not easily allow generation of a coherent numerical summary, studies were heterogeneous especially with regard to population, results were not consistent between studies, and study results almost universally lacked corroboration from other independent studies. CONCLUSION: No studies were found which examined natural history. Overall burden of metastatic disease, confirmed metastatic bone involvement and immediate symptomatology suggestive of spinal column involvement are already well known as factors for metastatic SCC, vertebral collapse or progression of vertebral collapse. Although we identified a large number of additional possible prognostic factors, those which currently offer the most potential are unclear. Current clinical consensus favours magnetic resonance imaging and CT imaging modalities for the investigation of SCC and vertebral fracture. Future research should concentrate on: (1) prospective randomised designs to establish clinical and quality-of-life outcomes and cost-effectiveness of identification and treatment of patients at high risk of vertebral collapse and SCC; (2) Service Delivery and Organisation research on magnetic resonance imaging (MRI) scans and scanning (in tandem with research studies on use of MRI to monitor progression) in order to understand best methods for maximising use of MRI scanners; and (3) investigation of prognostic algorithms to calculate probability of a specified event using high-quality prospective studies, involving defined populations, randomly selected and clearly identified samples, and with blinding of investigators. FUNDING: This report was commissioned by the National Institute for Health Research Health Technology Assessment Programme NIHR HTA Programme as project number HTA 10/91/01.

Surgical treatment and outcomes of metastatic breast cancer to the spine.

Metastatic vertebral body and spinal epidural lesions cause significant pain and neurological morbidity and negatively impact quality of life and survival. In instances of metastatic epidural spinal cord compression, treatment typically involves surgery and radiotherapy. The incidence of spinal metastases in breast cancer patients is high. In the light of recent improvements in survival among some patients with breast cancer, we reviewed the treatments and outcomes for patients with breast cancer who presented to our institution with metastatic epidural spinal cord compression. We identified all patients undergoing open surgery for the treatment of breast cancer metastases to the spine at our center from 1 January 2001 to 31 December 2009. We retrospectively reviewed records for the details of medical history, treatment, surgery, radiographic imaging, and follow-up. The Death Master File from the United States Social Security Administration was queried to identify the date of death where the medical record was incomplete. Outcomes were assessed by overall survival as well as preoperative and postoperative ambulatory status, bladder function, and the American Spinal Injury Association impairment classification system (ASIA). A total of 15 female patients were identified as having surgical intervention directly related to breast cancer metastasis to the spine. Most lesions (12/15) were located in the anterior vertebral column (vertebral body and/or pedicle). Two patients required re-operation, one for epidural fluid collection and one for infection. Roughly half of the patients (8/15) had well-controlled systemic disease at the time of surgery. Five patients had non-contiguous metastatic lesions elsewhere in the spine. Median survival following surgery was 1,025 days; control of systemic disease did not predict duration of postoperative survival. Seven patients had documented improvement in their ability to ambulate in the first 30 days following surgery. Bladder function was preserved in all. No patient deteriorated; and five patients had postoperative improvement of their ASIA impairment scale grade. We concluded that aggressive therapy, including surgery, is warranted for patients with symptomatic metastatic epidural spinal cord compression from breast cancer, including in the setting of advanced and progressive systemic disease.

Sacral tumor resection: the effect of surgical staging on patient outcomes, resource management, and hospital cost.

STUDY DESIGN: Single-institution retrospective study. OBJECTIVE: To assess the effect surgical staging (i.e., sequencing) has on clinical and economic outcomes for patients undergoing sacropelvic tumor resection requiring lumbopelvic stabilization. SUMMARY OF BACKGROUND DATA: Sacral corpectomy with lumbopelvic stabilization is an extensive surgical procedure that can be performed in either a single episode or multiple episodes of care on different days. The impact of varied sequencing of surgical episodes of care on patient, resource, and financial outcomes is unknown. METHODS: This single-center retrospective case series identified all cases of sacropelvic tumor resection requiring lumbopelvic stabilization over an 8-year period. We assessed and compared clinical and economic outcomes for patients whose anterior exposure and posterior resection were separated into two distinct surgical episodes of care (staged) versus patients whose anterior exposure and posterior resection occurred in a single encounter (nonstaged procedures). Primary endpoints included procedural outcomes (operative and after-hours surgical time), resuscitative requirements, adverse perioperative events, mortality, and direct medical costs (hospital and physician) associated with the surgical episodes of interest. RESULTS: From January 1, 2000, to July 15, 2008, a total of 25 patients were identified. Eight patients had their procedure staged. Surgical staging was associated with a significant increase in intensive care unit free days (P = 0.03), ventilator free days (P < 0.01), and reduced morbidity (P < 0.01). Surgical staging significantly reduced postoperative red blood cell (P = 0.03), and after-hours red blood cell (P < 0.01) and component requirements (P = 0.04). Mean total inpatient costs were $89,132 lower for patients undergoing the staged procedure (95% confidence interval of mean cost difference = -$178,899 to -$4661). CONCLUSION: Separating the anterior exposure and posterior resection phases of complex sacral tumor resection into two separate surgical episodes of care is associated with improved clinical outcomes and reduced inpatient cost.

Multiparameter MRI assessment of normal-appearing and diseased vertebral bone marrow.

OBJECTIVE: To evaluate spin-lattice (T1) and spin-spin (T2) relaxation times as well as apparent diffusion coefficients (ADCs) of the fat and water components in the vertebral bone marrow (vBM) of patients with benign and malignant lesions. METHODS: Forty-four patients were examined at 1.5 T: there were 24 osteoporotic vertebral fractures (15 women, 9 men; median age: 73, 48-86 years) and 20 malignant vertebral infiltrations (9 women, 11 men; median age: 60, 25-87). Relaxation times were determined separately for the water and the fat component using a saturation-recovery technique for T1 and measurements with variable echo times for T2. ADCs were determined with a diffusion-weighted (DW) echo-planar imaging (EPI) and a single-shot turbo-spin-echo (ssTSE) sequence. RESULTS: T1 of the water component and ADCs were significantly increased in the lesions compared with normal-appearing vBM (malignant: 1,252 vs. 828 ms, osteoporotic: 1,315 vs. 872 ms). ADCs determined with the DW-ssTSE were significantly increased compared with the DW-EPI. ADCs determined with the DW-ssTSE differed significantly between osteoporotic and malignant lesions (1.74 vs 1.35 x 10⁻³ mm²/s. CONCLUSIONS: All parameters exhibit significant differences between normal-appearing vBM and the lesions. However, only the ADCs determined with the DW-ssTSE differed significantly between osteoporotic fractures and malignant lesions, potentially allowing for a differential diagnosis of these two entities.

An assessment of the reliability of the Enneking and Weinstein-Boriani-Biagini classifications for staging of primary spinal tumors by the Spine Oncology Study Group.

STUDY DESIGN: Reliability analysis based on expert panel case series review and grading per the Enneking and Weinstein-Boriani-Biagini classification systems. OBJECTIVE: To assess the reliability of the Enneking and Weinstein-Boriani-Biagini classification systems. SUMMARY OF BACKGROUND DATA: The Enneking and Weinstein-Boriani-Biagini (WBB) classifications were developed to stage and facilitate treatment planning in patients with primary spine tumors. To date, their interobserver and intraobserver reliability has not been assessed-a fundamental step in facilitating broader clinical and research use. METHODS: Clinical information, imaging studies, and biopsy results were compiled from 15 selected patients with primary spinal tumors. Eighteen spine surgeons independently estimated and scored the cases for Enneking grade, tumor and metastasis categories, Enneking stage, Enneking-recommended surgical margin, WBB zones and layers, and WBB-recommended surgical procedures, with a second assessment performed after random resorting of cases. Interobserver and intraobserver reliability of each category were assessed by percent agreement or proportional overlap. The Fleiss, Cohen, and Mezzich kappa statistics (kappa) were then applied, determined by the type of variable analyzed. RESULTS: The kappa statistics for interobserver reliability were 0.82, 0.22, 0.00, 0.57, 0.47, 0.31, 0.58, and 0.54 for the fields of Enneking grade, tumor and metastasis categories, Enneking stage, Enneking-recommended surgical margin, WBB zones and layers, and WBB-recommended surgical procedures, respectively. The kappa statistics for intraobserver reliability were 0.97, 0.53, 0.47, 0.82, 0.67, 0.63, 0.79, and 0.79 for the same respective fields. According to Landis and Koch, the ranges of kappa values of 0.00 to 0.20, 0.21 to 0.40, 0.41 to 0.60, 0.61 to 0.80, and >0.80 imply slight, fair, moderate, substantial, and near-perfect agreement, respectively. CONCLUSION: Results indicate moderate interobserver reliability and substantial and near-perfect intraobserver reliability for both the Enneking and WBB classification in terms of staging and guidance for treatment, despite a less than moderate interobserver reliability in interpreting the Enneking local tumor extension and WBB sector. Before incorporating the classifications in the clinical practice and research studies, further work is required to investigate the validity of the classifications.

Percutaneous needle biopsy of the spine.

The purpose of this review article is to provide a brief overview of the recent literature on the two main types of percutaneous biopsy methods done in the spinal column: fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB). FNAB is the process of obtaining a sample of cells and bits of tissue for examination by applying suction through a fine needle attached to a syringe. Core needle biopsy involves extracting a cylindrical sample of tissue using a large, hollow needle. The decision for needle biopsy is a joint effort between the clinician, pathologist, radiologist, surgeon, and patient. Specific techniques and approaches with varying needle systems are described for each spinal region. Percutaneous image-guided spine biopsy is a safe and effective procedure. It is the procedure of choice in definitive diagnosis of pathologic lesions of the spine.

Level-adjusted perioperative risk of sacral amputations.

BACKGROUND AND OBJECTIVES: Sacral amputations above the S2 body often involve increased surgical complexity leading to long-term morbidity. The purpose of this study was to determine whether proximal sacral amputations have substantially higher perioperative morbidity compared with more distal sacral amputations. METHODS: We evaluated the effect of sacral amputation level on perioperative outcomes within 90 days of surgery. Outcome measures included blood loss, intensive care unit (ICU) and hospital stay, hospital cost, and incidence of a major and minor morbidity. Survival analyses were adjusted for the level of resection and histological appearance. RESULTS: Thirteen proximal and 14 distal resections were performed. In comparing proximal versus distal resections, median estimated blood loss was 4 L versus 1 L (P < 0.001), ICU stay was 4 days versus 0 days (P = 0.012), hospital stay was 19 days versus 8 days (P = 0.001), hospital cost was 28,800 dollars versus 7,500 dollars (P = 0.003), with one or more major complications in 85% versus 29% (P = 0.011). Survival analysis demonstrated that the sacral resection level did not influence survival (P = 0.936), whereas the type of tumor did influence survival (P = 0.012). CONCLUSION: Tumor resections above S2 demonstrate increased perioperative morbidity, suggesting that proximal osteotomies be reserved for patients with a realistic cure potential.

Metastatic burst fracture risk assessment based on complex loading of the thoracic spine.

The mechanical integrity of vertebral bone is compromised when metastatic cancer cells migrate to the spine, rendering it susceptible to burst fracture under physiologic loading. Risk of burst fracture has been shown to be dependent on the magnitude of the applied load, however limited work has been conducted to determine the effect of load type on the stability of the metastatic spine. The objective of this study was to use biphasic finite element modeling to evaluate the effect of multiple loading conditions on a metastatically-involved thoracic spinal motion segment. Fifteen loading scenarios were analyzed, including axial compression, flexion, extension, lateral bending, torsion, and combined loads. Additional analyses were conducted to assess the impact of the ribcage on the stability of the thoracic spine. Results demonstrate that axial loading is the predominant load type leading to increased risk of burst fracture initiation, while rotational loading led to only moderate increases in risk. Inclusion of the ribcage was found to reduce the potential for burst fracture by 27%. These findings are important in developing a more comprehensive understanding of burst fracture mechanics and in directing future modeling efforts. The results in this study may also be useful in advising less harmful activities for patients affected by lytic spinal metastases.

Quantitative assessment of diffusion abnormalities in benign and malignant vertebral compression fractures by line scan diffusion-weighted imaging.

OBJECTIVE: Acute vertebral collapse is common, and it is sometimes difficult to determine whether the cause is benign or malignant. Recently, diffusion-weighted imaging has been reported to be useful for differentiating the two types. The purpose of this study was to evaluate diffusion abnormalities quantitatively in benign and malignant compression fractures using line scan diffusion-weighted imaging. SUBJECTS AND METHODS. Line scan diffusion-weighted imaging was prospectively performed in 17 patients with 20 acute vertebral compression fractures caused by osteoporosis or trauma, in 12 patients with 16 vertebral compression fractures caused by malignant tumors, and in 35 patients with 47 metastatic vertebrae without collapse. Images were obtained at b values of 5 and 1,000 sec/mm(2). The apparent diffusion coefficient (ADC) was measured in vertebral compression fractures and metastatic vertebrae without collapse. RESULTS: The ADC (mean +/- SD) was 1.21 +/- 0.17 x 10(-3) mm(2)/sec in benign compression fractures, 0.92 +/- 0.20 x 10(-3) mm(2)/sec in malignant compression fractures, and 0.83 +/- 0.17 x 10(-3) mm(2)/sec in metastatic vertebral lesions without collapse. The ADC was significantly higher in benign compression fractures than in malignant compression fractures (p < 0.01), although the two types showed considerable overlap. CONCLUSION: Although the quantitative assessment of vertebral diffusion provides additional information concerning compressed vertebrae, the benign and malignant compression fracture ADC values overlap considerably. Therefore, even a quantitative vertebral diffusion assessment may not always permit a clear distinction between benign and malignant compression fractures.