A novel classification system for spinal instability in neoplastic disease: an evidence-based approach and expert consensus from the Spine Oncology Study Group

Spine radiosurgery for the local treatment of spine metastases: Intensity-modulated radiotherapy, image guidance, clinical aspects and future directions

Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and nonrandomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future.

An update in the management of spinal metastases

The best clinical treatment for spinal metastases requires an integrated approach with input from an interdisciplinary cancer team. The principle goals of treatment are maintenance or improvement in neurologic function and ambulation, spinal stability, durable tumor control, and pain relief. The past decade has witnessed an explosion of new technologies that have impacted our ability to reach these goals, such as separation surgery and minimally invasive spinal procedures. The biggest advance, however, has been the evolution of stereotactic radiosurgery that has demonstrated durable tumor control both when delivered as definitive therapy and as a postoperative adjuvant even for tumors considered markedly resistant to conventional external beam radiation. In this paper, we perform an update on the management of spinal metastases demonstrating the integration of these new technologies into a decision framework NOMS that assesses four basic aspects of a patient's spine disease: Neurologic, Oncologic, Mechanical Instability and Systemic disease.

Single-fraction versus multifraction spinal stereotactic radiosurgery for spinal metastases from renal cell carcinoma: secondary analysis of Phase I/II trials

OBJECTIVE The objective of this study was to compare fractionation schemes and outcomes of patients with renal cell carcinoma (RCC) treated in institutional prospective spinal stereotactic radiosurgery (SSRS) trials who did not previously undergo radiation treatment at the site of the SSRS. METHODS Patients enrolled in 2 separate institutional prospective protocols and treated with SSRS between 2002 and 2011 were included. A secondary analysis was performed on patients with previously nonirradiated RCC spinal metastases treated with either single-fraction (SF) or multifraction (MF) SSRS. RESULTS SSRS was performed in 47 spinal sites on 43 patients. The median age of the patients was 62 years (range 38-75 years). The most common histological subtype was clear cell (n = 30). Fifteen sites underwent surgery prior to the SSRS, with laminectomy the most common procedure performed (n = 10). All SF SSRS was delivered to a dose of 24 Gy (n = 21) while MF regiments were either 27 Gy in 3 fractions (n = 20) or 30 Gy in 5 fractions (n = 6). The median overall survival duration for the entire cohort was 22.8 months. The median local control (LC) for the entire cohort was 80.6 months with 1-year and 2-year actuarial LC rates of 82% and 68%, respectively. Single-fraction SSRS correlated with improved 1- and 2-year actuarial LC relative to MF SSRS (95% vs 71% and 86% vs 55%, respectively; p = 0.009). On competing risk analysis, SF SSRS showed superior LC to MF SSRS (subhazard ratio [SHR] 6.57, p = 0.014). On multivariate analysis for LC with tumor volume (p = 0.272), number of treated levels (p = 0.819), gross tumor volume (GTV) coverage (p = 0.225), and GTV minimum point dose (p = 0.97) as covariates, MF SSRS remained inferior to SF SSRS (SHR 5.26, p = 0.033) CONCLUSIONS SSRS offers durable LC for spinal metastases from RCC. Single-fraction SSRS is associated with improved LC over MF SSRS for previously nonirradiated RCC spinal metastases.

What's new in vertebral cementoplasty?

Vertebral cementoplasty is a well-known mini-invasive treatment to obtain pain relief in patients affected by vertebral porotic fractures, primary or secondary spine lesions and spine trauma through intrametameric cement injection. Two major categories of treatment are included within the term vertebral cementoplasty: the first is vertebroplasty in which a simple cement injection in the vertebral body is performed; the second is assisted technique in which a device is positioned inside the metamer before the cement injection to restore vertebral height and allow a better cement distribution, reducing the kyphotic deformity of the spine, trying to obtain an almost normal spine biomechanics. We will describe the most advanced techniques and indications of vertebral cementoplasty, having recently expanded the field of applications to not only patients with porotic fractures but also spine tumours and trauma.

Early surgical occipitocervical stabilization for plasma cell neoplasms at the craniocervical junction: systematic review and proposal of a treatment algorithm

BACKGROUND CONTEXT

Plasma cell neoplasms (PCNs) of the craniocervical junction (CCJ) are rare. Because of their destructive growth, PCNs may induce spinal instability and harbor the risk of sudden death. Therefore, PCNs at the CCJ require special consideration. Although the commonly used primary treatment of PCN is radiotherapy (RT), treatment guidelines are inexistent for CCJ occurrences.

PURPOSE

This study aimed to conduct a systematic review of the literature, evaluate the benefit of early and extended surgical treatment followed by RT, and outline a treatment algorithm based on the data gathered.

STUDY DESIGN/SETTING

Case series and systematic review of all reported cases in the English, Spanish and German medical literature were carried out.

CASE SERIES

retrospective clinical study, tertiary care center (2004-2014). Patients with a lesion of the CCJ (C0-C2) were identified. Clinical charts, imaging data, operative reports, and follow-up data were analyzed.

REVIEW

a systematic literature review was performed using PubMed. Further manuscripts were identified by the web search engine Google.

RESULTS

Our series comprised four patients (one female, three males), mean age 58 years. There was one lesion of C1 and three of C2. Two patients with neck pain received vertebroplasty (C1 and C2, respectively) and RT as primary management. Both developed secondary instability of the CCJ after 12 and 5 months, respectively, and required occipitocervical stabilization (OCS). The other two patients underwent OCS and required no additional surgery and no signs of instability at follow-up. Forty-nine cases of OCS were published previously. Spinal stability was achieved significantly more frequently by OCS than by less invasive or medical interventional treatment options (p=.001; two-sided Fisher exact test).

CONCLUSIONS

Plasma cell neoplasms are highly radiosensitive. However, at the CCJ, a life-threatening instability may occur early and require surgical treatment. Based on personal experience, we favor OCS in this location. A systematic review of the literature supports this approach. We present a summary of our findings in a concise treatment algorithm for PCN of the CCJ.

The Effect of Introducing the Spinal Instability Neoplastic Score in Routine Clinical Practice for Patients With Spinal Metastases

BACKGROUND

Stable spinal metastases are effectively treated with radiotherapy, whereas unstable spinal metastases often need surgical fixation followed by radiotherapy for local control. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic related instability with the goal of helping to guide referrals among oncology specialists. We compare the average degree of spinal instability between patients with spinal metastases referred for surgery or for radiotherapy and evaluate whether this difference changed after introduction of the SINS in clinical practice.

METHODS

All patients with spinal metastases treated with palliative surgery or radiotherapy in the period 2009-2013 were identified in two spine centers. For all patients, the SINS was scored on pretreatment imaging. The SINS before and after introduction of the SINS in 2011 were compared within the surgical and radiotherapy group. Furthermore, the overall SINS was compared between the two groups.

RESULTS

The overall SINS was significantly higher in the surgical group, with a mean SINS of 10.7 (median 11) versus 7.2 (median 8) for the radiotherapy group. The mean SINS decreased significantly for both groups after introduction of the SINS in clinical practice from 11.2 to 10.3 in the surgical group and from 8.4 to 7.2 in the radiotherapy group.

CONCLUSION

The SINS differed significantly between patients treated with surgery or radiotherapy. The introduction of SINS led to a decrease in SINS score for both groups, suggesting that using SINS in metastatic spinal disease increases awareness for instability and may subsequently result in earlier referrals for surgical intervention.

IMPLICATIONS FOR PRACTICE

Spinal metastases can present with varying degrees of mechanical instability. Because unstable spinal metastases may respond insufficiently to palliative radiotherapy and can lead to loss of ambulation, timely detection and appropriate referral are important. The Spinal Instability Neoplastic Score (SINS) may help physicians caring for patients with metastasized disease to identify spinal instability before the onset of neurological deficits. In this study, it was shown that the introduction of SINS in routine practice led to a decrease in spinal instability in radiotherapy and surgical cohorts. The use of SINS may increase awareness of instability and subsequently result in earlier referrals.

Can the spinal instability neoplastic score prior to spinal radiosurgery predict compression fractures following stereotactic spinal radiosurgery for metastatic spinal tumor?: a post hoc analysis of prospective phase II single-institution trials

The aim of this study was to determine the predictability of vertebral compression fracture (VCF) development applying the spinal instability neoplastic score (SINS) prior to delivery of stereotactic spinal radiosurgery (SSRS) for spinal metastases. From two prospective cohorts of SSRS for spinal metastases, we selected patients with a low degree of cord compression or cauda equine from C3 to S1 and analyzed 79 patients enrolled according to binary SINS criteria. The primary endpoint was the development of a de novo VCF or progression of an existing fracture after SSRS. We identified 32 fractures (40.5%): 19 de novo and 13 progressive. The mean time to fracture after SSRT was 3.3 months (range, 0.4-34.1 months). In 41 patients with low SINS (0-6), 7 patients (17.1%) developed a fracture after SSRS. In 38 patients with high SINS (7-12), 25 (65.8%) developed a fracture. Among the 32 fractures, 15 were symptomatic. Patients with high SINS were more likely to experience symptomatic fractures (31.6%) than were patients with lower SINS (7.4%). On univariate and multivariate analysis, 24-month fracture-free rates were 78.7 and 33.7% in low and high SINS group, respectively and high SINS was found to be a significant risk factor for VCFs and symptomatic fractures (respectively, HR 5.6, p = 0.04; HR 5.3, p = 0.01). SINS is a useful tool for predicting the development of VCF after SSRS for spinal metastases. Prophylactic cement augmentation should not be considered for patients with lower SINS, since the risk of fracture is low.

ASSESSMENT OF SCORES IN DECISION MAKING IN METASTASES OF THE SPINE

Objective : The aim of this study is to assess the intra- and interobserver concordance of SINS, Harrington, Tokuhashi and Tomita scores among general orthopedic surgeons and spine surgeons with experience above 5 and 10 years in the evaluation of patients with spinal metastasis. Methods : Twenty cases of patients with metastatic lesion of the spine were presented to 10 examiners and the scores aforementioned have been applied. After six weeks, the cases were reintroduced in a different order and data were analyzed. Results : The intraobserver reliability showed better agreement in SINS score among examiners with less experience and Harrington and Tomita scores among those who had more than 10-year experience. The interobserver reliability of the examiners of the group with over 10-year experience showed higher precision when using these scores, especially Harrington and Tomita. The SINS score was the choice for daily practice and was able to modify the management more often. Conclusions : This study demonstrated that the use of predictive scores of instability, Harrington, and prognosis, Tomita, had a higher intra- and interobserver reliability particularly among spine surgeons with experience above 10 years.

Reliability assessment of a novel cervical spine deformity classification system

OBJECT

Despite the complexity of cervical spine deformity (CSD) and its significant impact on patient quality of life, there exists no comprehensive classification system. The objective of this study was to develop a novel classification system based on a modified Delphi approach and to characterize the intra- and interobserver reliability of this classification.

METHODS

Based on an extensive literature review and a modified Delphi approach with an expert panel, a CSD classification system was generated. The classification system included a deformity descriptor and 5 modifiers that incorporated sagittal, regional, and global spinopelvic alignment and neurological status. The descriptors included: “C,” “CT,” and “T” for primary cervical kyphotic deformities with an apex in the cervical spine, cervicothoracic junction, or thoracic spine, respectively; “S” for primary coronal deformity with a coronal Cobb angle ≥ 15°; and “CVJ” for primary craniovertebral junction deformity. The modifiers included C2–7 sagittal vertical axis (SVA), horizontal gaze (chin-brow to vertical angle [CBVA]), T1 slope (TS) minus C2–7 lordosis (TS–CL), myelopathy (modified Japanese Orthopaedic Association [mJOA] scale score), and the Scoliosis Research Society (SRS)-Schwab classification for thoracolumbar deformity. Application of the classification system requires the following: 1) full-length standing posteroanterior (PA) and lateral spine radiographs that include the cervical spine and femoral heads; 2) standing PA and lateral cervical spine radiographs; 3) completed and scored mJOA questionnaire; and 4) a clinical photograph or radiograph that includes the skull for measurement of the CBVA. A series of 10 CSD cases, broadly representative of the classification system, were selected and sufficient radiographic and clinical history to enable classification were assembled. A panel of spinal deformity surgeons was queried to classify each case twice, with a minimum of 1 intervening week. Inter- and intrarater reliability measures were based on calculations of Fleiss k coefficient values.

RESULTS

Twenty spinal deformity surgeons participated in this study. Interrater reliability (Fleiss k coefficients) for the deformity descriptor rounds 1 and 2 were 0.489 and 0.280, respectively, and mean intrarater reliability was 0.584. For the modifiers, including the SRS-Schwab components, the interrater (round 1/round 2) and intrarater reliabilities (Fleiss k coefficients) were: C2–7 SVA (0.338/0.412, 0.584), horizontal gaze (0.779/0.430, 0.768), TS-CL (0.721/0.567, 0.720), myelopathy (0.602/0.477, 0.746), SRS-Schwab curve type (0.590/0.433, 0.564), pelvic incidence-lumbar lordosis (0.554/0.386, 0.826), pelvic tilt (0.714/0.627, 0.633), and C7-S1 SVA (0.071/0.064, 0.233), respectively. The parameter with the poorest reliability was the C7–S1 SVA, which may have resulted from differences in interpretation of positive and negative measurements.

CONCLUSIONS

The proposed classification provides a mechanism to assess CSD within the framework of global spinopelvic malalignment and clinically relevant parameters. The intra- and interobserver reliabilities suggest moderate agreement and serve as the basis for subsequent improvement and study of the proposed classification.

STANDARDIZED TERMINOLOGY OF ADULT SPINE DEFORMITY FOR BRAZILIAN PORTUGUESE

Objective : To develop a consensus for translation of the most relevant terms used in the study of Adult Spinal Deformity, from their original languages into Brazilian Portuguese. Methods : A panel of 12 experts in spine surgery from the five Brazilian regions was constituted. To obtain the standardization of terminology, the Delphi method with an electronic questionnaire was administered to participants about their opinion on the translation of 13 relevant terms chosen by literature review. Each term was considered standard when there was consensus, that is, concordance higher than 80% among participants as to the suggestion to be adopted, and then on the acceptance of the term and its abbreviation in Portuguese. Results : Initially there was consensus (over 80% concordance) on the translation of seven terms in the electronic questionnaire. The other six terms that have not reached consensus were discussed at a meeting among the participants, relying on the opinion of a specialized professional in simultaneous translation of orthopedic terms in Portuguese and other professional majored in Portuguese language. It was decided how these terms should be translated and there was a consensus among all participants regarding their acceptance. Finally, there was consensus among the participants, who agreed with the translation and abbreviation of the 13 propose terms, defining its standardization for Brazilian Portuguese. Conclusion : We present a standard terminology used in the study of Adult Spinal Deformity through consensus among experts, seeking uniformity in the use of these terms in Brazilian Portuguese.

Clinical outcome of vertebral compression fracture after single fraction spine radiosurgery for spinal metastases

Vertebral compression fracture (VCF) occurs after stereotactic body radiation therapy (SBRT) for spine metastasis. Recently, single fraction radiosurgery (sfSRS) is used more frequently. The aim of this study is to determine the clinical outcome of VCF after sfSRS. Spinal instability neoplastic score (SINS) criteria were used to retrospectively score 143 consecutive vertebral segments in 79 patients treated with SRS. Follow-up MRI, pain, and neurologic assessments obtained every 3-6 months. Pain also scored at 7, 14, and 30 days after sfSRS. Follow up was 16 ± 18 months ±SD, range 3-78. Long-term radiographic control occurred in 94 % of cases. Pain improvement resulted within 7 days in 100 % of cases with severe pain and sustained long-term in 95 %. VCF occurred in 21 % of segments: 30 % were de novo VCF. The overall 1 year fracture free probability (1yFFP) was 76 %. Pre-existing VCF resulted in higher probability to progress: 1yFFP 90 versus 60 %. Symptoms presented in 6 % of cases with de novo VCF and 39 % with progressive. The former were treated with vertebral augmentation (VA), the latter with open surgery. Surgery/VA prior to SRS did not change risk of progressive VCF. Univariate but not multivariate analysis identified histology (colorectal), pre-existing VCF, and pain (severe) as significant predictors of VCF. In conclusion, sfSRS compares favourably to SBRT for radiographic and pain control with similar VCF risk. Patients with pre-existing VCF have a higher probability to progress, become symptomatic, and require surgery. These results may help discussing risk and benefits with patients undergoing sfSRS for spinal metastasis and developing new treatment algorithms.

Late failure of posterior fixation without bone fusion for vertebral metastases

OBJECTIVE

: To verify the frequency of late radiological com-plications in spinal fixation surgeries performed without fu-sion in oncological patients

METHODS

: This is a retrospective analysis analysing failure in cases of non-fused vertebral fixation in an oncology reference hospital between 2009 and 2014. Failure was defined as implant loosening or bre-akage, as well as new angular or translation deformities

RESULTS

: One hundred and five cases were analyzed. The most common site of primary tumor was the breast and the most common place of metastasis was the thoracic spine. The average follow-up was 22.7 months. Nine cases (8%) of failure were reported, with an average time until failure of 9.5 months. The most common failure was implant loosening. No case required further surgery

CONCLUSION

: The occurrence of failure was not different than that reported for fused cases. The time interval until failure was higher than the median of survival of the majority (88%) of cases. Level of Evidence IV, Therapeutic Study.

The influence of orthopedic corsets on the incidence of pathological fractures in patients with spinal bone metastases after radiotherapy

BACKGROUND

Clinical care of unstable spinal bone metastases in many centers often includes patient immobilization by means of an orthopedic corset in order to prevent pathological fractures. The aim of this retrospective analysis was to evaluate the incidence of pathological fractures after radiotherapy (RT) in patients with and without orthopedic corsets and to assess prognostic factors for pathological fractures in patients with spinal bone metastases.

METHODS

The incidence of pathological fractures in 915 patients with 2.195 osteolytic metastases in the thoracic and lumbar spine was evaluated retrospectively on the basis of computed tomography (CT) scans between January 2000 and January 2012 depending on prescription and wearing of patient-customized orthopedic corsets.

RESULTS

In the corset group, 6.8 and 8.0 % in no-corset group showed pathological fractures prior to RT, no significant difference between groups was detected (p = 0.473). After 6 months, patients in the corset group showed pathological fractures in 8.6 % and in no-corset group in 9.3 % (p = 0.709). The univariate and bivariate analyses demonstrated no significant prognostic factor for incidence of pathological fractures in both groups.

CONCLUSIONS

In this analysis, we could show for the first time in more than 900 patients, that abandoning a general corset supply in patients with spinal metastases does not significantly cause increased rates of pathological fractures. Importantly, the incidence of pathological fracture after RT was small.

The Metastatic Spine Disease Multidisciplinary Working Group Algorithms

The Metastatic Spine Disease Multidisciplinary Working Group consists of medical and radiation oncologists, surgeons, and interventional radiologists from multiple comprehensive cancer centers who have developed evidence- and expert opinion-based algorithms for managing metastatic spine disease. The purpose of these algorithms is to facilitate interdisciplinary referrals by providing physicians with straightforward recommendations regarding the use of available treatment options, including emerging modalities such as stereotactic body radiation therapy and percutaneous tumor ablation. This consensus document details the evidence supporting the Working Group algorithms and includes illustrative cases to demonstrate how the algorithms may be applied.

The unruptured intracranial aneurysm treatment score: a multidisciplinary consensus

OBJECTIVE

We endeavored to develop an unruptured intracranial aneurysm (UIA) treatment score (UIATS) model that includes and quantifies key factors involved in clinical decision-making in the management of UIAs and to assess agreement for this model among specialists in UIA management and research.

METHODS

An international multidisciplinary (neurosurgery, neuroradiology, neurology, clinical epidemiology) group of 69 specialists was convened to develop and validate the UIATS model using a Delphi consensus. For internal (39 panel members involved in identification of relevant features) and external validation (30 independent external reviewers), 30 selected UIA cases were used to analyze agreement with UIATS management recommendations based on a 5-point Likert scale (5 indicating strong agreement). Interrater agreement (IRA) was assessed with standardized coefficients of dispersion (vr*) (vr* = 0 indicating excellent agreement and vr* = 1 indicating poor agreement).

RESULTS

The UIATS accounts for 29 key factors in UIA management. Agreement with UIATS (mean Likert scores) was 4.2 (95% confidence interval [CI] 4.1-4.3) per reviewer for both reviewer cohorts; agreement per case was 4.3 (95% CI 4.1-4.4) for panel members and 4.5 (95% CI 4.3-4.6) for external reviewers (p = 0.017). Mean Likert scores were 4.2 (95% CI 4.1-4.3) for interventional reviewers (n = 56) and 4.1 (95% CI 3.9-4.4) for noninterventional reviewers (n = 12) (p = 0.290). Overall IRA (vr*) for both cohorts was 0.026 (95% CI 0.019-0.033).

CONCLUSIONS

This novel UIA decision guidance study captures an excellent consensus among highly informed individuals on UIA management, irrespective of their underlying specialty. Clinicians can use the UIATS as a comprehensive mechanism for indicating how a large group of specialists might manage an individual patient with a UIA.

Surgical management of metastatic lesions at the cervicothoracic junction

PURPOSE

The cervicothoracic junction (CTJ) represents a transition from the semirigid thoracic spine to the mobile subaxial cervical spine. Pathologic lesions are prone to kyphotic deformity. The aim of this study was to review our experience with surgical stabilization of metastatic lesions affecting the CTJ (C7-T2).

MATERIALS AND METHODS

We reviewed all surgical stabilizations of metastatic spine lesions over the preceding 4 years in our institution. A total of 14 patients with CTJ lesions were identified. Case notes and radiology were reviewed to determine the presentation, outcomes, and specific complications.

RESULTS

The mean survival was 405 days (standard deviation [s.d.] 352). 8/14 died at a mean time from surgery of 193 days (s.d. 306). Most cases were a result of either lung or breast primary tumors. Half were stabilized with an anterior only approach and two had staged anterior-posterior. There were no cases of neurologic deterioration in this cohort as a result of surgery. There were two cases of deep surgical site infection and two documented cases of pulmonary embolus. There were no reported construct failures over the follow-up period.

CONCLUSION

Patients with cervicothoracic metastatic lesions can be treated with either anterior or posterior approaches or a combination after considering each individual's potential instability and disease burden.

Factors Affecting Survival in Patients Undergoing Palliative Spine Surgery for Metastatic Lung and Hepatocellular Cancer: Dose the Type of Surgery Influence the Surgical Results for Metastatic Spine Disease?

Background

Surgical treatment for metastatic spine disease has been becoming more prominent with the help of technological advances and a few favorable reports on the surgery. In cases of this peculiar condition, it is necessary to establish the role of surgery and analyze the factors affecting survival.

Methods

From January 2011 to April 2015, 119 patients were surgically treated for metastatic spine lesions. To reduce the bias along the heterogeneous cancers, the primary cancer was confined to either the lung (n = 25) or the liver (n = 18). Forty-three patients (male, 32; female, 11; mean age, 57.5 years) who had undergone palliative surgery were enrolled in this study. Posterior decompression and fusion was performed in 30 patients (P group), and anteroposterior (AP) reconstruction was performed in 13 patients (AP group) for palliative surgery. Pre- and postoperative (3 months) pain (visual analogue scale, VAS), performance status (Karnofsky performance score), neurologic status (American Spinal Injury Association [ASIA] grade), and spinal instability neoplastic score (SINS) were compared. The survival period and related hazard factors were also assessed by Kaplan-Meier and Cox regression analysis.

Results

Most patients experienced improvements in pain and performance status (12.3% ± 17.2%) at 3 months postoperatively. In terms of neurologic recovery, 9 patients (20.9%) graded ASIA D experienced neurological improvement to ASIA E while the remainder was status quo. In an analysis according to operation type, there was no significant difference in patient demographics. At 12 months postoperatively, cumulative survival rates were 31.5% and 38.7% for the P group and the AP group, respectively (p > 0.05). Survival was not affected by the pre- and postoperative pain scale, Tokuhashi score, neurologic status, SINS, or operation type. Preoperative Karnofsky performance score (hazard ratio, 0.93; 95% confidence interval [CI], 0.89 to 0.96) and improvement of performance status after surgery (hazard ratio, 0.95; 95% CI, 0.92 to 0.97) significantly affected survival after operation.

Conclusions

There was no significant difference in surgical outcomes and survival rates between posterior and AP surgery for metastatic lesions resulting from lung and hepatocellular cancer. Preoperative Karnofsky score and improvement of performance status had a significant impact on the survival rate following surgical treatment for these metastatic spine lesions.

The era of stereotactic body radiotherapy for spinal metastases and the multidisciplinary management of complex cases

Spinal metastases are increasingly becoming a focus of attention with respect to treating with locally "ablative" intent, as opposed to locally "palliative" intent. This is due to increasing survival rates among patients with metastatic disease, early detection as a result of increasing availability of spinal MRI, the recognition of the oligometastatic state as a distinct sub-group of favorable metastatic patients and the advent of stereotactic body radiotherapy (SBRT). Although conventionally fractionated radiation therapy has been utilized for decades, the rates of complete pain relief and local control for complex tumors are sub-optimal. SBRT has the advantage of delivering high total doses in few fractions (typically, 24 Gy in 1 or 2 fractions to 30-45 Gy in 5 fractions) that can be considered "ablative". With mature clinical experience emerging among early adopters, we are realizing beyond efficacy the limitations of spine SBRT. In particular, toxicities such as vertebral compression fracture, and epidural disease progression as the most common pattern of local tumor progression. As a result, the multidisciplinary evaluation of cases prior to SBRT is emphasized with the intent to identify patients who could benefit from surgical stabilization or down-staging of epidural disease. The purpose of this review is to provide an overview of the current literature with respect to outcomes, technical details for safe delivery, patient selection criteria, common and uncommon side effects of therapy, and the increasing use of minimally invasive surgical techniques that can improve both safety and local control.

Utilization of laser interstitial thermotherapy guided by real-time thermal MRI as an alternative to separation surgery in the management of spinal metastasis

OBJECT

High-grade malignant spinal cord compression is commonly managed with a combination of surgery aimed at removing the epidural tumor, followed by spinal stereotactic radiosurgery (SSRS) aimed at local tumor control. The authors here introduce the use of spinal laser interstitial thermotherapy (SLITT) as an alternative to surgery prior to SSRS.

METHODS

Patients with a high degree of epidural malignant compression due to radioresistant tumors were selected for study. Visual analog scale (VAS) scores for pain and quality of life were obtained before and within 30 and 60 days after treatment. A laser probe was percutaneously placed in the epidural space. Real-time thermal MRI was used to monitor tissue damage in the region of interest. All patients received postoperative SSRS. The maximum thickness of the epidural tumor was measured, and the degree of epidural spinal cord compression (ESCC) was scored in pre- and postprocedure MRI.

RESULTS

In the 11 patients eligible for study, the mean VAS score for pain decreased from 6.18 in the preoperative period to 4.27 within 30 days and 2.8 within 60 days after the procedure. A similar VAS interrogating the percentage of quality of life demonstrated improvement from 60% preoperatively to 70% within both 30 and 60 days after treatment. Imaging follow-up 2 months after the procedure demonstrated a significant reduction in the mean thickness of the epidural tumor from 8.82 mm (95% CI 7.38-10.25) before treatment to 6.36 mm (95% CI 4.65-8.07) after SLITT and SSRS (p = 0.0001). The median preoperative ESCC Grade 2 was scored as 4, which was significantly higher than the score of 2 for Grade 1b (p = 0.04) on imaging follow-up 2 months after the procedure.

CONCLUTIONS

The authors present the first report on an innovative minimally invasive alternative to surgery in the management of spinal metastasis. In their early experience, SLITT has provided local control with low morbidity and improvement in both pain and the quality of life of patients.

Short-segment percutaneous pedicle screw fixation with cement augmentation for tumor-induced spinal instability

BACKGROUND CONTEXT

Pathologic vertebral compression fractures (VCFs) represent a major source of morbidity and diminished quality of life in the spinal oncology population. Procedures with low morbidity that effectively treat patients with pathologic fractures are especially important in the cancer population where life expectancy is limited. Vertebroplasty and kyphoplasty are often not effective for mechanically unstable pathologic fractures extending into the pedicle and facet joints. Combination of cement augmentation and percutaneous instrumented stabilization represents a minimally invasive treatment option that does not delay radiation and systemic therapy.

PURPOSE

The objective of the study was to evaluate the safety and efficacy of cement-augmented short-segment percutaneous posterolateral instrumentation for tumor-associated VCF with pedicle and joint involvement.

METHODS

Forty-four consecutive patients underwent cement-augmented percutaneous spinal fixation for unstable tumors between 2011 and 2014. Retrospective analysis of prospectively collected data, including visual analog pain scale (VAS) response score and procedural complications, was performed.

RESULTS

Patients with a median composite Spinal Instability Neoplastic Scale score of 10 (range=8-15) were treated with constructs spanning one to four disk spaces (median of two spaces, constituting 84% of all cases). The proportion of patients with severe pain decreased from 86% preoperatively to 0%; 65% of patients reported no referable instability pain postoperatively. There was one adjacent-level fracture responsive to kyphoplasty, and one case of asymptomatic screw pullout. Two patients subsequently required decompression in the setting of disease progression despite radiation; there was no perioperative morbidity.

CONCLUSIONS

Percutaneous cement-augmented posterolateral spinal fixation is a safe and effective option for palliation of appropriately selected mechanically unstable VCF that extends into pedicle and/or joint.

Improved patient selection by stratified surgical intervention: Aarhus Spinal Metastases Algorithm

BACKGROUND CONTEXT

Choosing the best surgical treatment for patients with spinal metastases remains a significant challenge for spine surgeons. There is currently no gold standard for surgical treatments. The Aarhus Spinal Metastases Algorithm (ASMA) was established to help surgeons choose the most appropriate surgical intervention for patients with spinal metastases.

PURPOSE

The purpose of this study was to evaluate the clinical outcome of stratified surgical interventions based on the ASMA, which combines life expectancy and the anatomical classification of patients with spinal metastases to inform surgical decision making.

STUDY DESIGN/SETTING

This is a retrospective study based on a prospective database.

PATIENT SAMPLE

A consecutive series of 515 spinal metastatic patients who underwent surgically treatment from December 1992 to June 2012 in Aarhus University Hospital were included prospectively and analyzed in detail retrospectively.

OUTCOME MEASURES

Survival time after surgery was determined for all patients. Neurological function was assessed using the Frankel score preoperatively and postoperatively (at the time of discharge). Complete outcome data were retrieved in 97.5% of this cohort.

METHODS

Patients with spinal metastases were identified from an institutional database that prospectively collected data since 1992. Survival status data were obtained from a national registry. Neurological function was determined from the same institutional database or local Electronic Patient Journal system. Surgeons evaluated and classified patients into five surgical groups preoperatively by using the revised Tokuhashi score (TS) and the Tomita anatomical classification (TC).

RESULTS

The overall median survival time of the cohort was 6.8 (95% confidence interval: 6.1-7.9) months. The median survival times in the five surgical groups determined by the ASMA were 2.1 (TS 0-4, TC 1-7), 5.1 (TS 5-8, TC 1-7), 12.1 (TS 9-11, TC 1-7 or TS 12-15, TC 7), 26.0 (TS 12-15, TC 4-6), and 36.0 (TS 12-15, TC 1-3) months. The 30-day mortality rate was 7.5%. Postoperative neurological function was maintained or improved in 469 patients (92.3%). Overall reoperation rate was 13.5%, commonly because of postoperative hematoma and new limb weakness.

CONCLUSIONS

The ASMA recommends at least two surgical options for a particular patient by determining the preoperative life expectancy and anatomical classification of the spinal metastases. This algorithm could help spine surgeons to discriminate the risks of surgeries. The ASMA provides a tool to guild surgeons to evaluate the spinal metastases patients, select potential optimal surgery, and avoid life-threatening risks.

Spine metastases: are minimally invasive surgical techniques living up to the hype?

Surgery is still considered the mainstay treatment of spine metastases. However, conventional surgery is associated with a high complication rate that may delay the initiation of adjuvant therapies and make some patients not eligible. Minimally invasive surgical techniques have been developed to overcome these drawbacks while providing the same benefits than standard open surgery. In recent years, there has been a flourishing enthusiasm demonstrating the advantages of these various techniques. Although, it is clear that these techniques have greatly improved the treatment of spine metastases, each has its own limitations. In this report, we list the main minimally invasive surgical techniques emphasizing their advantages and drawbacks.

Current trends in mini-invasive management of spine metastases

The spine is a frequent localization of primary tumours or metastasis involving posterior arch, pedicles and vertebra body, and often causing unsustainable pain. The management of spinal metastasis remains complex, including medical therapy (corticosteroids, chemotherapy), radiotherapy and surgical treatment, or the recent percutaneous mini-invasive approach. The target of all these treatments is to improve the quality of life of patients affected by this type of lesion. Diagnosis of spinal metastasis and then its treatment should be based on the combination of different elements: clinical evaluation, CT, MRI and nuclear medicine patterns, considering the age of the patient, known primary tumour, location of the lesions, single/multiple lesions, pattern of morphology (border, matrix, expansile character, soft tissue extension), density or signal intensity, oncologic instability and expectancy of life. The percutaneous mini-invasive approach for patients affected by secondary lesions involving the spine has as treatment goal of: (1) pain relief improving the quality of life; (2) stability treatment re-establishing the spinal biomechanics, alterated by bone destruction or deformity, preventing pathological fracture; and (3) an anti-neoplastic effect. The aim of this paper is to provide a comprehensive diagnostic and percutaneous approach to the bone metastatic spine lesions, identifying which metamer should be treated to improve patient quality of life, showing the importance of a multi-disciplinary approach to this problem.

Spinal hemangiomas: results of surgical management for local recurrence and mortality in a multicenter study

STUDY DESIGN

Multicenter, ambispective observational study.

OBJECTIVE

To quantify local recurrence and mortality rates after surgical treatment of symptomatic spinal hemangiomas and identify prognostic variables for local disease control.

SUMMARY OF BACKGROUND DATA

Spinal hemangiomas are the most common primary tumors of the spine and are generally benign and usually asymptomatic. Because of the rarity of symptomatic spinal hemangiomas, optimal surgical treatment remains unclear.

METHODS

AOSpine Knowledge Forum Tumor Investigators created a multicenter database of primary spinal tumors including demographics, presentation, diagnosis, treatment, survival, and recurrence data. Tumors were classified according to Enneking and Weinstein-Boriani-Biagini. Descriptive statistics were summarized and time to mortality and recurrence was determined.

RESULTS

Between 1996 and 2012, 68 patients (mean age = 51 yr, SD = 16) underwent surgical treatment of a spinal hemangioma. Epidural disease was present in 55% of patients (n = 33). Pain and neurological compromise were presenting symptoms in 82% (n = 54) and 37% (n = 24) of patients, respectively. Preoperative embolization was performed in 35% of patients (n = 23), 10% (n = 7) had adjuvant radiotherapy, and 81% (n = 55) underwent posterior-alone surgery. The local recurrence rate was 3% (n = 2). Mortality secondary to spinal hemangioma was not observed (mean follow-up = 3.9 yr, SD = 3.8).

CONCLUSION

This is the largest multicenter surgical cohort of spinal hemangiomas. Symptomatic spinal hemangiomas are a benign tumor despite frequently presenting with epidural disease and neurological compromise. Thus, formal en bloc resection is not required, and excellent rates of local control and long-term survival can result from aggressive intralesional resection during index surgery.

LEVEL OF EVIDENCE

3.

Stereotactic body radiotherapy: a new paradigm in the management of spinal metastases

Spine stereotactic body radiotherapy is based on delivering high biologically effective doses to spinal metastases, with the intent to maximize both tumor and pain control. The purpose of this review is to outline the technical details of spine stereotactic body radiotherapy, contrast clinical outcomes to low biologically effective dose conventional palliative radiotherapy, discuss the role of surgery in the era of spine stereotactic body radiotherapy, and summarize the major serious adverse events that patients would otherwise not be at risk of with conventional radiotherapy.

Role of stereotactic body radiotherapy in spinal metastasis and subsequent fracture risk: identifying and treating the at-risk patient

The treatment of spinal metastasis has considerably improved with the advent of stereotactic body radiotherapy. Technological advances have enabled the precise delivery of high-dose radiation that may supplant surgery and standard fractionation postoperative radiation as a treatment for spinal metastasis without cord compression. Unfortunately, the higher biologically equivalent doses conferred by stereotactic body radiotherapy can also result in radiation toxicity, notably myelitis and vertebral body fracture. These are toxicities that the radiation oncologist must be able to anticipate, mitigate and manage. Although myelitis can be prevented largely by instituting dose constraints, it is less clear what the fracture risk of a structurally compromised vertebra is, and what should be done in terms of stabilization and dosimetry to mitigate this risk. This review answers these questions by defining the appropriate patient for stereotactic body radiotherapy, and what dose, fractionation and spinal stabilization should be used for potentially unstable spines.

Reoperation rates in the surgical treatment of spinal metastases

BACKGROUND CONTEXT

The surgical treatment in spinal metastases has been shown to improve function and neurologic outcome. Unplanned hospital readmissions can be costly and cause unnecessary harm.

PURPOSE

Our aim was to first analyze the reoperation rate and indications for this revision surgery in spinal metastases from an academic tertiary spinal institute and, second, to make comparisons on outcome (neurology and survival) against patients who underwent single surgery only.

STUDY DESIGN/SETTING

This was an ambispective review of all patients treated surgically over an 8-year period considering their neurologic and survival outcome data. Statistical analysis was performed using IBM SPSS 20. Because all scale values did not follow the normal distribution and significant outlier values existed, all descriptive statistics and comparisons were made using median values and the median test. Crosstabs and Pearson correlation were used to calculate differences between percentages and ordinal/nominal values. For two population proportions, the z test was used to calculate differences. The log-rank Mantel-Cox analysis was used to compare survival.

PATIENT SAMPLE

During the 8 years' study period, there were 384 patients who underwent urgent surgery for spinal metastasis. Of these, 289 patients were included who had sufficient information available. There were 31 reoperations performed (10.7%; mean age, 60 years; 13 male, 18 female). Exclusion criteria included patients treated solely by radiotherapy, patients who had undergone surgery for spinal metastasis before the study period, and those who had other causes for neurologic dysfunction such as stroke.

OUTCOME MEASURES

The outcomes considered in this study were revised Tokuhashi score, preoperative/postoperative Frankel scores, and survival.

METHODS

We performed an ambispective review of all patients treated surgically from our comprehensive database during the study period (October 2004 to October 2012). We reviewed all patient records on the database, including patient demographics and reoperation rates.

RESULTS

Reoperations were performed in the same admission in the majority of patients (n=20), whereas 11 patients had their second procedure in subsequent hospitalization. The reasons for their revision surgery were as follows: surgical site infection (SSI; 13 of 31 [42%]), failure of instrumentation (9 of 31 [29%]), local recurrence (5 of 31 [16%]), hematoma evacuation (2 of 31 [6%]), and others (2 of 31 [6%]).When comparing the "single surgery" and "revision surgery" groups, we found that the median preoperative and postoperative Frankel scores were similar at Grade 4 (range, 1-5) for both groups (preoperative, p=.92; postoperative, p=.87). However, 20 patients (8%) from the single surgery group and 7 (23%) from the revision group had a worse postoperative score, and this was significantly different (p=.01). No significant difference was found (p=.66) in the revised Tokuhashi score. The median number of survival days was similar (p=.719)-single surgery group: 250 days (range, 5-2,597 days) and revision group: 215 days (range, 9-1,352 days).

CONCLUSION

There was a modest reoperation rate (10.7%) in our patients treated surgically for spinal metastases over an 8-year period. Most of these were for SSI (42%), failure of instrumentation (26%), and local recurrence (16%). Patients with metastatic disease could benefit from revision surgery with comparable median survival rates but relatively poorer neurologic outcomes. This study may help to assist with informed decision making for this vulnerable patient group.

Outcomes following surgical intervention for impending and gross instability caused by multiple myeloma in the spinal column

OBJECT

Multiple myeloma is the most common primary tumor of the spine and is the most common primary malignant tumor of bone. Although spinal myeloma is classically a radiosensitive lesion, clinical or radiographic signs of instability merit surgical intervention. The authors present the epidemiology, surgical indications, and outcome data of a series of consecutive cases involving 31 surgically treated patients with diagnoses of multiple myeloma and plasmacytoma of the spine (the largest such series reported to date).

METHODS

Surgical instability was the criterion for operative intervention in this patient cohort. The Spinal Instability Neoplastic Score (SINS) was used to make this assessment of instability. The cases were analyzed using location of the lesion, spinal levels involved, Frankel score, adjuvant therapy, functional outcome, and patient survival.

RESULTS

All patients undergoing surgical intervention were determined to have indeterminate or gross spinal column instability according to SINS criteria. The median survival was 78.9 months. No significant difference in survival was seen for patients with higher SINS scores or for older patients (> 55 years). There was a statistically significant difference in survival benefit observed for patients receiving chemotherapy and radiation versus radiation alone as an adjuvant to surgery (p = 0.02).

CONCLUSIONS

In this 10-year analysis, the authors report outcomes of surgical intervention for patients with indeterminate or gross spinal instability due to multiple myeloma and plasmacytoma of the spine with improved neurological function following surgery and low rates of instrumentation failure.

Spinal neoplastic instability: biomechanics and current management options

BACKGROUND

Often the spine is afflicted from primary or metastatic neoplastic disease, which can lead to instability. Instability can cause deformity, pain, and spinal cord compression and is an indication for surgery. Although overt instability is uniformly agreed upon, it is sometimes difficult for specialists to agree on subtle degrees of instability due to lack of objective criteria.

METHODS

In this article, treatment options and the spine instability neoplastic system are discussed and the neoplastic instability literature is reviewed.

RESULTS

The Spinal Instability Neoplastic Score helps specialists determine whether instability is present and when surgery may be indicated. However, other parameters such as spinal cord compression and extent of disease dictate whether surgery is the most appropriate option. A wide range of fusion techniques exists, each one tailored to the location of the lesion and goals for surgery.

CONCLUSIONS

To optimize results, expert knowledge on the techniques and patient selection is of importance. Furthermore, a multidisciplinary approach is required because treatment of neoplastic disease is multimodal.

Separation surgery for spinal metastases: effect of spinal radiosurgery on surgical treatment goals

BACKGROUND

The treatment of epidural spinal cord compression due to metastatic cancer represents an important clinical challenge. The NOMS (neurologic, oncologic, mechanical, and systemic) framework facilitates the determination of the optimal combination of systemic, radiation, and surgical therapies for individual patients. Spinal stereotactic radiosurgery (SRS) is an effective and safe modality for achieving durable control of local disease. Integrating SRS into the postoperative treatment plan allows surgical goals to be modified, thus decreasing the extent of tumor resection required.

METHODS

Separation surgery is indicated for patients with spinal cord compression secondary to solid tumor metastases. During separation surgery, the spinal column is stabilized and the epidural tumor is resected without requiring significant vertebral body resection.

RESULTS

Tumor separation from the spinal cord allows patients to undergo postoperative SRS.

CONCLUSIONS

The combination of separation surgery and high-dose hypofractionated or single-fraction SRS results in high local tumor control at 1 year and is an effective palliative paradigm for this patient population.

Controversial issues in kyphoplasty and vertebroplasty in malignant vertebral fractures

BACKGROUND

Kyphoplasty (KP) and vertebroplasty (VP) have been successfully employed in the treatment of pathological vertebral fractures.

METHODS

A critical review of the medical literature was performed and controversial issues were analyzed.

RESULTS

Evidence supports KP as the treatment of choice to control fracture pain and the possible restoration of sagittal balance, provided that no overt instability or myelopathy is present, the fracture is painful and other pain generators have been excluded, and positive radiological findings are present. Unilateral procedures yield similar results to bilateral ones and should be pursued whenever feasible. Biopsy should be routinely performed and 3 to 4 levels may be augmented in a single operation. Higher cement filling appears to yield better results. Radiotherapy is complementary with KP and VP but must be individualized.

CONCLUSIONS

In cases of painful cancer fractures, if overt instability or myelopathy is not present, unilateral KP should be pursued, whenever feasible, followed by radiotherapy. The technological advances in hardware and biomaterials, as well as combining KP with other modalities, will help ensure a safe and more effective procedure. Address.

Vertebral compression fractures after spine irradiation using conventional fractionation in patients with metastatic colorectal cancer

Purpose

To evaluate the risk of vertebral compression fracture (VCF) after conventional radiotherapy (RT) for colorectal cancer (CRC) with spine metastasis and to identify risk factors for VCF in metastatic and non-metastatic irradiated spines.

Materials and Methods

We retrospectively reviewed 68 spinal segments in 16 patients who received conventional RT between 2009 and 2012. Fracture was defined as a newly developed VCF or progression of an existing fracture. The target volume included all metastatic spinal segments and one additional non-metastatic vertebra adjacent to the tumor-involved spines.

Results

The median follow-up was 7.8 months. Among all 68 spinal segments, there were six fracture events (8.8%) including three new VCFs and three fracture progressions. Observed VCF rates in vertebral segments with prior irradiation or pre-existing compression fracture were 30.0% and 75.0% respectively, compared with 5.2% and 4.7% for segments without prior irradiation or pre-existing compression fracture, respectively (both p < 0.05). The 1-year fracture-free probability was 87.8% (95% CI, 78.2-97.4). On multivariate analysis, prior irradiation (HR, 7.30; 95% CI, 1.31-40.86) and pre-existing compression fracture (HR, 18.45; 95% CI, 3.42-99.52) were independent risk factors for VCF.

Conclusion

The incidence of VCF following conventional RT to the spine is not particularly high, regardless of metastatic tumor involvement. Spines that received irradiation and/or have pre-existing compression fracture before RT have an increased risk of VCF and require close observation.

Factors affecting survival in 37 consecutive patients undergoing de novo stereotactic radiosurgery for contiguous sites of vertebral body metastasis from renal cell carcinoma

OBJECT

Palliative resection of renal cell carcinoma (RCC) spinal metastasis is indicated in cases of neurological compromise or mechanical instability, whereas conventional external beam radiotherapy (EBRT) is commonly used for pain control. Recently, spinal stereotactic radiosurgery (SRS) has emerged as a safe alternative, delivering higher therapeutic doses of radiation to spinal metastases. To better understand factors affecting survival in patients undergoing spinal SRS for metastatic RCC, the authors performed a retrospective analysis of a consecutive series of cases at a tertiary cancer center.

METHODS

Patients harboring contiguous sites of vertebral body involvement from metastatic RCC who received upfront spinal SRS treatment at The University of Texas MD Anderson Cancer Center between 2005 and 2012 were identified. Demographic data, pain scores, radiographic data, overall survival, complications, status of systemic disease, neurological and functional status, and time between primary diagnosis and diagnosis of metastasis (systemic and spinal) were analyzed to determine their influence on survival.

RESULTS

Thirty-seven patients receiving treatment for 40 distinct, contiguous sites of disease were included. The median overall survival after spinal SRS was 16.3 months (range 7.4–25.3 months). Univariate analysis revealed several factors significantly associated with improved overall survival. Local progression after spinal SRS was associated with worse overall survival compared with sustained local control (HR 3.4, 95% CI 1.6–7.4, p = 0.002). Median survival in patients with a Karnofsky Performance Scale (KPS) score ≥ 70 was longer than in patients with a KPS score < 70 (HR 4.7, 95% CI 2.1–10.7, p < 0.001). Patients with neurological deficits at the time of spinal SRS had a shorter median survival than those without (HR 4.2, 95% CI 1.4–12.0, p = 0.008). Individuals with nonprogressive systemic disease at the time of spinal SRS had a longer median survival than those with systemic progression at the time of treatment (HR 8.3, 95% CI 3.3–20.7, p < 0.001). Median survival in patients experiencing any metastasis < 12 months after primary RCC diagnosis was shorter than in patients experiencing any metastasis > 12 months after primary diagnosis, a difference that approached but did not attain significance (HR 1.9, 95% CI 0.90–4.1, p = 0.09). On multivariate analysis, local progression of disease after spinal SRS, metastasis < 12 months after primary, KPS score ≤ 70, and progression of systemic disease at time of spinal SRS all remained significant factors influencing survival (respectively, HR 3.7, p = 0.002; HR 2.6, p = 0.026; HR 4.0, p = 0.002; and HR 13.2, p < 0.001).

CONCLUSIONS

We identified several factors associated with survival after spinal SRS for RCC metastases, including local progression, time between first metastasis and primary RCC diagnosis, KPS score, presence of neurological deficits, and progressive metastatic disease. These factors should be taken into consideration when considering a patient for spinal SRS for RCC metastases.

The current status and future of radiotherapy for spinal bone metastases

The management of spinal bone metastases is complex. In this review, the efficacy, methodology, and utilization of radiotherapy (RT) for spinal bone metastases are discussed. A number of randomized trials have evaluated the efficacy of 8 Gy, single-fraction RT for the palliation of painful bone metastases. However, RT for metastatic spinal cord compression has not been evaluated with respect to its optimal dose, palliative potential, or its ability to improve motor function. Two highly sophisticated RT techniques - stereotactic body RT (SBRT) and intensity-modulated RT (IMRT) - have recently been adapted for the treatment of spinal bone metastases, and both have the potential to achieve excellent control while minimizing acute and late toxicity. SBRT and IMRT are particularly well suited for the treatment of spinal bone metastases when they are localized or require re-irradiation, and may provide superior tumor control. Predicting the prognosis of patients with bone metastases and assessing spinal instability are both important when selecting the optimal RT method and deciding whether to perform surgery. The proper care of spinal bone metastases patients requires an interdisciplinary treatment approach.

Oligometastases in prostate cancer: restaging stage IV cancers and new radiotherapy options

There are various subgroups of patients with metastatic prostate cancer: polymetastatic, oligometastatic, or oligo-recurrent cancers whose progression follows different courses and for whom there are different treatment options. Knowledge of tumor dissemination pathways and different genetic and epigenetic tumor profiles, as well as their evolution during disease progression, along with new diagnostic and therapeutic advances has allowed us to address these situations with local ablative treatments such as stereotactic body radiation therapy or stereotactic radiosurgery. These treatments provide high rates of local control with low toxicity in metastatic spread for primary cancers including those of pulmonary, digestive, and renal origin, while these types of treatments are still emerging for cancers of prostatic origin. There are several retrospective studies showing the effectiveness of such treatments in prostate cancer metastases, which has led to the emergence of prospective studies on the issue and even some phase II studies intended to prevent or delay systemic treatments such as chemotherapy. Here we collect together and review these past experiences and the studies currently underway. These types of radiotherapy treatments redefine how we approach extracranial metastatic disease and open up new possibilities for combination therapy with new systemic treatment agents.

Contemporary Treatment Strategy for Spinal Metastasis: The “LMNOP” System

The choice of treatment for spinal metastasis is complex because (1) it depends on several inter-related clinical and radiologic factors, and (2) a wide range of management options has evolved in recent years. While radiation therapy and surgery remain the cornerstones of treatment, radiosurgery and percutaneous vertebral augmentation have also established a role. Classification systems have been developed to aid in the decision-making process, and each has different strengths and weaknesses. The comprehensive scoring systems developed to date provide an estimate of life expectancy, but do not provide much advice on the choice of treatment. We propose a new decision model that describes the key factors in formulating the management plan, while recognizing that the care of each patient remains highly individualized. The system also incorporates the latest changes in technology. The LMNOP system evaluates the number of spinal Levels involved and the Location of disease in the spine (L), Mechanical instability (M), Neurology (N), Oncology (O), Patient fitness, Prognosis and response to Prior therapy (P).

Spinal instability as defined by the spinal instability neoplastic score is associated with radiotherapy failure in metastatic spinal disease

BACKGROUND CONTEXT

Although radiotherapy is effective in achieving pain relief in most patients, it is not completely understood why some patients respond well to radiotherapy and others do not. Our hypothesis was that metastatic bone pain, if predominantly caused by mechanical instability of the spine, responds less well to radiotherapy than metastatic bone pain caused by local tumor activity. Recently, the spinal instability neoplastic score (SINS) was proposed as a standardized referral tool for nonspine specialists to facilitate early diagnosis of spinal instability.

PURPOSE

To investigate the association between spinal instability as defined by the SINS and response to radiotherapy in patients with spinal metastases.

STUDY DESIGN

A retrospectively matched case-control study in an academic tertiary referral center, conducted according to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines.

PATIENT SAMPLE

Thirty-eight patients with spinal metastases who were retreated after initial palliative radiotherapy from January 2009 to December 2010 were matched to 76 control patients who were not retreated.

OUTCOME MEASURES

Radiotherapy failure as defined by retreatment (radiotherapy, surgery, and conservative) after palliative radiotherapy for spinal metastases.

METHODS

Radiotherapy planning computed tomography scans were scored by a blinded spine surgeon according to the SINS criteria. The association between SINS and radiotherapy failure was estimated by univariate and multivariate conditional logistic regression analysis.

RESULTS

Median SINS was 10 (range 4-16) for cases and 7 (range 1-16) for controls. The SINS was significantly and independently associated with radiotherapy failure (adjusted odds ratio, 1.3; 95% confidence interval, 1.1-1.5; p=.01).

CONCLUSIONS

This study shows that a higher spinal instability score increases the risk of radiotherapy failure in patients with spinal metastases, independent of performance status, primary tumor, and symptoms. These results may support the hypothesis that metastatic spinal bone pain, predominantly caused by mechanical instability, responds less well to radiotherapy than pain mainly resulting from local tumor activity.

Occipitoaxial spinal interarticular stabilization with vertebral artery preservation for atlantal lateral mass failure

The treatment of craniocervical instability caused by diverse conditions remains challenging. Different techniques have been described to stabilize the craniocervical junction. The authors present 2 cases in which tumoral destruction of the C-1 lateral mass caused craniocervical instability. A one-stage occipitoaxial spinal interarticular stabilization (OASIS) technique with titanium cages and posterior occipitocervical instrumentation was used to reconstruct the C-1 lateral mass and stabilize the craniocervical junction. The ipsilateral vertebral artery was preserved. The OASIS technique offers single-stage tumor resection, C-1 lateral mass reconstruction, and stabilization with a loadsharing construct. It could be an option in the treatment of select cases of C-1 lateral mass failure.

Modern surgical techniques for management of soft tissue sarcomas involving the spine: outcomes and complications

Several types of soft tissue sarcomas may locally extend to the spine. The best therapeutic strategy for such lesions strongly depends on the histological diagnosis. In this article the authors provide an up-to-date review of current guidelines regarding the management of soft tissue sarcomas involving the spine. Special attention is given to outcomes and complications of modern surgical series in order to highlight current challenges in the management of such lesions.

Reliability of the spinal instability neoplastic scale among radiologists: an assessment of instability secondary to spinal metastases

OBJECTIVE

The spinal instability neoplastic scale (SINS) is a new classification system for tumor-related spinal instability. The SINS may prove to be a valuable tool for radiologists to communicate with oncologists and surgeons in a standardized evidence-based manner. The objective of this study was to determine the inter- and intraobserver reliability and validity of the SINS among radiologists.

MATERIALS AND METHODS

Thirty-seven radiologists from 10 international sites used the SINS to categorize the degree of spinal instability in 30 patients with spinal tumors. To assess validity, we compared the SINS scores assigned by the radiologists with the SINS scores of 11 spine oncology surgeons (reference standard). Each total SINS score (range, 0-18 points) was converted into one of the following three clinical categories: 0-6 points, stable; 7-12 points, potentially unstable; and 13-18 points, unstable. In addition, each total SINS score was converted into a binary scale: 0-6 points was defined as stable, and 7-18 points was considered a current or possible instability for which surgical consultation is recommended.

RESULTS

Radiologists using the SINS binary scale showed excellent (κ = 0.88) validity, substantial (κ = 0.76) interobserver agreement, and excellent (κ = 0.82) intraobserver reproducibility. Radiologists rated all unstable cases and 621 of 629 (98.7%) potentially unstable cases with a SINS score of 7 or more points, thus appropriately initiating a referral for surgical assessment.

CONCLUSION

SINS is a reliable tool for radiologists rating tumor-related spinal instability. It accurately discriminates between stable and potentially unstable or unstable lesions and, therefore, can guide the need for surgical consultation.

Management of neoplastic spinal tumors in a spine surgery care unit

BACKGROUND CONTEXT

Spinal cord compression and fracture are possible complications of spine metastasis and multiple myeloma. Prompt diagnosis and treatment of threatening lesions are likely to reduce the frequency of these dreaded complications.

PURPOSE

To evaluate the proportion of neoplastic spine lesions operated on emergency.

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

All patients who underwent palliative surgery for the treatment of a neoplastic spine lesion in our institution between 2005 and 2012.

OUTCOME MEASURES

Percentage of patients who underwent surgery as an emergency for acute fracture or rapid neurological decline.

METHODS

We retrospectively reviewed the data of all patients who underwent palliative surgery for the treatment of a neoplastic spine lesion from solid cancer or multiple myeloma, in our institution between January 2005 and December 2012. The study was supported by grant from our institution.

RESULTS

A total of 317 patients were included in the study. There were 166 men and 151 women and the mean age was 57.97 years (range 26-88; SD 12.45). The cancer was known for 224 patients, while the lesion revealed the disease for the other 93 patients. The percentage of patients with known cancer operated as an emergency in our institution decreased significantly between 2005 and 2012 (p = 0.0006).

CONCLUSION

Due to the variability of clinical and radiological presentations, best care requires a truly multidisciplinary approach, to offer each patient a prompt and individualized treatment option, which is likely to reduce the incidence of emergency surgeries.

Primary Spinal Tumor Mortality Score (PSTMS): a novel scoring system for predicting poor survival

BACKGROUND CONTEXT

Although the surgical and oncological therapies of primary spinal tumors (PSTs) have changed significantly over the last few decades, the prognosis of this rare disease is still poor. The decision-making process in the multidisciplinary management is handicapped by the lack of large-scale population-based prognostic studies.

PURPOSE

The objective of the present study was to investigate preoperative factors associated with PST mortality and to develop a predictive scoring system of poor survival.

STUDY DESIGN

This is a large-scale ambispective cohort study.

PATIENT SAMPLE

The study included 323 consecutive patients with PSTs, treated surgically over an 18-year period at a tertiary care spine referral center for a population of 10 million.

OUTCOME MEASURE

Survival was the outcome measure.

METHODS

Patients were randomly divided into a training cohort (n=273) and a validation cohort (n=50). In the training cohort, 12 preoperative factors were investigated using Cox proportional hazard models. Based on the mortality-related variables, a simple scoring system of mortality was created, and three groups of patients were identified. Kaplan-Meier and log-rank analyses were used to compare the survival in the three groups. The model performance was assessed by measuring the discriminative ability (c-index) of the model and by applying a pseudo-R(2) goodness-of-fit test (Nagelkerke R(2), RN(2)). Internal validation was performed using bootstrapping in the training cohort and assessing the discrimination and explained variation of the model in the validation cohort.

RESULTS

Patient age, spinal region, tumor grade, spinal pain, motor deficit, and myelopathy/cauda equina syndrome were significantly associated with poor survival in the multivariate analysis (p<.001, RN(2)=0.799). Based on these variables, we developed the Primary Spinal Tumor Mortality Score (PSTMS), where an eight-point scale was divided into three categories (low, medium, and high mortality). The three PSTMS categories were significantly associated with the overall survival (p<.001, RN(2)=0.811, c=0.82). The model performance remained similarly high in the validation cohort (RN(2)=0.831, c=0.81).

CONCLUSIONS

The present study identifies six predictive variables for mortality in PSTs. Using these six variables, an easy-to-use scoring system was developed that can be applied to the estimation of postoperative survival in all types of PST patients.