Evaluation and treatment of spinal metastases: an overview

Does Timing of Radiation Therapy Impact Wound Healing in Patients Undergoing Metastatic Spine Surgery?

INTRODUCTION

The impact of radiation on wound healing after metastatic spine surgery remains an active area of research. In patients undergoing metastatic spine surgery, we sought to (1) assess the relationship between preoperative and/or postoperative radiation on wound complications, and (2) evaluate the relationship between the timing of postoperative radiation and wound complications.

METHODS

A single-center, retrospective, cohort study of patients undergoing metastatic spine surgery was conducted from 2010 to 2021. The primary exposure variable was the use/timing of radiation. Radiation included both external beam radiotherapy (EBRT) and stereotactic body radiotherapy (SBRT). Patients were trichotomized into the following groups: (1) preoperative radiation only, (2) postoperative radiation only, and (3) no radiation. The primary outcome variable was wound complications, which was defined as dehiscence requiring reoperation, infection requiring antibiotics, or infection requiring surgical debridement. Multivariable logistic/linear regression controlled for age, tumor size, primary organ of origin, and the presence of other organ metastases.

RESULTS

A total of 207 patients underwent surgery for extradural spinal metastasis. Participants were divided into three groups: preoperative RT only (N = 29), postoperative RT only (N = 91), and no RT (N = 178). Patients who received postoperative RT only and no RT were significantly older than patients who received preoperative RT only (p = 0.009) and were less likely to be white (p < 0.001). No other significant differences were found in basic demographics, tumor characteristics, or intraoperative variables. Wound-related complications occurred in two (6.9%) patients with preoperative RT only, four patients (4.4%) in postoperative RT only, and 11 (6.2%) patients with no RT, with no significant difference among the three groups (p = 0.802). No significant difference was found in wound-related complications, reoperation, and time to wound complications between patients with preoperative RT only and no RT, and between postoperative RT only and no RT (p > 0.05). Among the postoperative-RT-only group, no difference in wound complications was seen between those receiving SBRT (5.6%) and EBRT (4.1%) (p > 0.999). However, patients who received preoperative RT only had a longer time to wound complications in comparison to those who received postoperative RT only (43.5 ± 6.3 vs. 19.7 ± 3.8, p = 0.004). Regarding timing of postoperative RT, the mean (SD) time to RT was 28.7 ± 10.0 days, with a median of 28.7 (21-38) days. No significant difference was found in time to postoperative RT between patients with and without wound complications (32.9 ± 12.3 vs. 29.0 ± 9.7 days, p = 0.391).

CONCLUSION

In patients undergoing metastatic spine surgery, a history of previous RT or postoperative RT did not significantly affect wound complications. However, those with previous RT prior to surgery had a longer time to wound complications than patients undergoing postoperative RT only. Moreover, timing of RT had no impact on wound complications, indicating that earlier radiation may be safely employed to optimize tumor control without fear of compromising wound healing.

Does Elective Admission vs. Emergency Department Presentation Affect Surgical Outcomes in Metastatic Spine Surgery?

INTRODUCTION

Approximately 20% of patients with metastatic spine disease develop symptomatic spinal cord compression, and these patients can present urgently to the emergency department (ED) or, in a more organized fashion, to a clinic. In a cohort of patients undergoing metastatic spine surgery, we sought to (1) determine the rate of ED presentation, (2) identify preoperative and perioperative risk factors associated with ED presentation, and (3) evaluate whether ED vs. clinic presentation impacts long-term outcomes.

METHODS

A single-institution, multi-surgeon, retrospective cohort study was undertaken of patients undergoing metastatic spinal tumor surgery between 02/2010 and 01/2021. The primary exposure variable was presentation setting, dichotomized to the ED vs. clinic. The primary outcomes were postoperative functional status, measured with the Karnofsky Performance Scale (KPS) and McCormick Scale (MMS), local recurrence (LR), and overall survival (OS). Secondary outcomes included complications and readmissions.

RESULTS

A total of 311 patients underwent metastatic spine surgery (51.7% ED vs. 48.3% clinic). Those presenting to the ED had higher rates of smoking (21.7% vs. 16.0%, p = 0.02), were more likely to have 2+ comorbidities (47.2% vs. 32.7%, p = 0.011), and were more likely to have public insurance (43.5% vs. 32.0%, p = 0.043). Preoperative KPS was lower in ED patients (p < 0.001), while the Bilsky score was higher (p = 0.049). ED patients had higher rates of oligometastatic disease (p = 0.049), higher total decompressed levels (p = 0.041), and higher rates of costotransversectomy (p = 0.031) compared to clinic patients. Length of stay was significantly longer for ED patients (7.7 ± 6.1 vs. 6.1 ± 5.8 days, p = 0.020), and they were less likely to be discharged home (52.2% vs. 69.3%, p = 0.025). ED presentation was significantly associated with shorter overall survival (HR =1.53 95% CI = 1.13-2.08, p = 0.006).

CONCLUSIONS

Of patients undergoing metastatic spine disease, approximately half presented through the ED vs. clinic. ED patients had higher rates of smoking, public insurance, and higher Bilsky score. ED patients also underwent more extensive surgery, had longer LOS, were less likely discharged home, and most importantly, had a shorter overall survival. These results suggest that initial presentation for patients undergoing surgery for metastatic spine disease significantly impacts outcomes, and signs/symptoms of metastatic spine disease should be recognized as soon as possible to prevent ED presentation.

Surgical management of tumors of the cervical spine and craniovertebral junction involving the vertebral artery: A narrative review

BACKGROUND

The vertebral artery (VA) is in close proximity to bony structures, nerves and nerve sheaths of the cervical spine and craniovertebral junction (CVJ). These structures can be sources of tumors that are responsible for displacement, encasement and sometimes invasion of the VA. Removing these tumors while minimizing the risk of vascular injury requires thorough knowledge of the vascular anatomy, risk factors of vascular injury, the relationships of each tumor type with the VA, and the different surgical approaches and techniques that result in the best outcomes in terms of vascular control, tumoral exposure and resection.

OBJECTIVE

To present an overview of preoperative and anatomical considerations, differential diagnoses and various approaches to consider in cases of tumors in close relationship with the VA.

METHOD

A review of recent literature was conducted to examine the anatomy of the VA, the tumors most frequently affecting it, surgical approaches, and the necessary pre-operative preparations for ensuring safe and maximal tumor resection. This review aims to underscore the principles of treatment.

CONCLUSION

Tumors located at the CVJ and the cervical spine intimately involved with the VA, pose a surgical challenge and increase the risk of incomplete removal of the lesion. Detailed knowledge of the patient-specific anatomy and a targeted pre-operative work-up enable optimal planning of surgical approach and management of the VA, thereby reducing surgical risks and improving extent of resection.

A new era in the management of spinal metastasis

Despite the recent advances in cancer treatment, the incidence of patients with spinal metastases continues to grow along with the total number of cancer patients. Spinal metastases can significantly impair activities of daily living (ADL) and quality of life (QOL), compared with other types of bone metastases, as they are characterized with severe pain and paralysis caused by skeletal-related events. Reduced ADL can also lead to treatment limitations as certain anticancer agents and radiation therapy are not compatible treatments; thus, leading to a shorter life expectancy. Consequently, maintaining ADLs in patients with spinal metastases is paramount, and spine surgeons have an integral role to play in this regard. However, neurosurgeon, orthopedic and spinal surgeons in Japan do not have a proactive treatment approach to spinal metastases, which may prevent them from providing appropriate treatment when needed (clinical inertia). To overcome such endemic inertia, it is essential for 1) spine surgeons to understand and be more actively involved with patients with musculoskeletal disorders (cancer locomo) and cancer patients; 2) the adoption of a multidisciplinary approach (coordination and meetings not only with the attending oncologist but also with spine surgeons, radiologists, rehabilitation specialists, and other professionals) to preemptive treatment such as medication, radiotherapy, and surgical treatment; and 3) the integration of the latest findings associated with minimally invasive spinal treatments that have expanded the indications for treatment of spinal metastases and improved treatment outcomes. This heralds a new era in the management of spinal metastases.

Synchronous versus metachronous spinal metastasis: a comparative study of survival outcomes following neurosurgical treatment

PURPOSE

Patients with spinal metastases (SM) from solid neoplasms typically exhibit progression to an advanced cancer stage. Such metastases can either develop concurrently with an existing cancer diagnosis (termed metachronous SM) or emerge as the initial indication of an undiagnosed malignancy (referred to as synchronous SM). The present study investigates the prognostic implications of synchronous compared to metachronous SM following surgical resection.

METHODS

From 2015 to 2020, a total of 211 individuals underwent surgical intervention for SM at our neuro-oncology facility. We conducted a survival analysis starting from the date of the neurosurgical procedure, comparing those diagnosed with synchronous SM against those with metachronous SM.

RESULTS

The predominant primary tumor types included lung cancer (23%), prostate cancer (21%), and breast cancer (11.3%). Of the participants, 97 (46%) had synchronous SM, while 114 (54%) had metachronous SM. The median overall survival post-surgery for those with synchronous SM was 13.5 months (95% confidence interval (CI) 6.1-15.8) compared to 13 months (95% CI 7.7-14.2) for those with metachronous SM (p = 0.74).

CONCLUSIONS

Our findings suggest that the timing of SM diagnosis (synchronous versus metachronous) does not significantly affect survival outcomes following neurosurgical treatment for SM. These results support the consideration of neurosurgical procedures regardless of the temporal pattern of SM manifestation.

Outcomes in Patients with Spinal Metastases Managed with Surgical Intervention

BACKGROUND

Spinal metastases are a significant cause of morbidity in patients with advanced cancer, and management often requires surgical intervention. Although prior studies have identified factors that influence outcomes with surgery, the ability of these factors to predict outcomes remains unclear in the era of contemporary therapies, and there is a need to better identify patients who are likely to benefit from surgery.

METHODS

We performed a single-center, retrospective analysis to evaluate risk factors for poor outcomes in patients with spinal metastases treated with surgery. The primary outcome was mortality at 180 days.

RESULTS

A total of 128 patients were identified. Age ≥ 65 years at surgery (p = 0.0316), presence of extraspinal metastases (p = 0.0110), and ECOG performance scores >1 (p = 0.0397) were associated with mortality at 180 days on multivariate analysis. These factors and BMI ≤ 30 mg/kg2 (p = 0.0008) were also associated with worse overall survival.

CONCLUSIONS

Age > 65, extraspinal metastases, and performance status scores >1 are factors associated with mortality at 180 days in patients with spinal metastases treated with surgery. Patients with these factors and BMI ≤ 30 mg/kg2 had worse overall survival. Our results support multidisciplinary discussions regarding the benefits and risks associated with surgery in patients with these risk factors.

Effectiveness of gelatin matrix with human thrombin for reducing blood loss in palliative decompressive surgery with posterior spinal fusion for metastatic spinal tumors

BACKGROUND

This study aimed to investigate the effect of gelatin matrix with human thrombin (GMHT) on blood loss and survival time in patients with metastatic spinal tumors treated with palliative decompression surgery with posterior spinal fusion.

METHODS

We retrospectively reviewed 67 consecutive patients with metastatic spinal tumors who underwent palliative decompression surgery with posterior spinal fusion. We compared patients in whom GMHT was not used during surgery with those in whom GMHT was used. The following baseline characteristics were evaluated: age, height, weight, sex, metastatic tumor diagnosis, medical history, use of antiplatelet drug, use of anticoagulant drug, use of NSAIDs, smoking, preoperative PLT value, preoperative APTT, preoperative PT-INR, Karnofsky Performance Status score, Charlson comorbidities index score, the percentage of patients who received perioperative chemotherapy, main tumor level, Frankel category, revised Tokuhashi score, spinal instability neoplastic score (SINS), number of fusion segments, operation time, intraoperative blood loss, drainage blood loss, red blood cell transfusion, hemoglobin level, total protein (TP), albumin values, total blood loss (TBL), hidden blood loss, postoperative bed rest and postoperative survival time. Perioperative complications were assessed.

RESULTS

Age, height, weight, sex, metastatic tumor diagnosis, medical history, use of antiplatelet drug, use of anticoagulant drug, use of NSAIDs, smoking, preoperative PLT value, preoperative APTT, preoperative PT-INR, CCI score, main level of tumors, SINS score, preoperative Tokuhashi score and number of fusion segments did not differ significantly between the two groups. Operation time, intraoperative blood loss, postoperative drainage blood loss, and TBL were significantly decreased in the group with GMHT than in the group without GMHT. The total number of perioperative complications was significantly lesser in the group with GMHT than in the group without GMHT. The median postoperative survival time was significantly longer in the GMHT group than in the group without GMHT.

CONCLUSION

GMHT should be considered a valid option for the treatment of patients with metastatic spinal tumors with a short life expectancy.

Comparison of Outcomes in Patients with Cervical Spine Metastasis After Different Surgical Approaches: A Single-Center Experience

OBJECTIVE

In patients undergoing cervical spine surgery for metastatic spine disease, we sought to 1) compare perioperative and oncologic outcomes among 3 different operative approaches, 2) report fusion rates, and 3) compare different types of anterior vertebral body replacement.

METHODS

A single-center retrospective cohort study of patients undergoing extradural cervical/cervicothoracic spine metastasis surgery between February 2010 and January 2021 was conducted. Operative approaches were anterior-alone, posterior-alone, or combined anterior-posterior, and the grafts/cages used in the anterior fusions were cortical allografts, static cages, or expandable cages. All cages were filled with autograft/allograft. Outcomes included perioperative/postoperative variables, along with fusion rates, functional status, local recurrence (LR), and overall survival (OS).

RESULTS

Sixty-one patients underwent cervical spine surgery for metastatic disease, including 11 anterior (18.0%), 28 posterior (45.9%), and 22 combined (36.1%). New postoperative neurologic deficit was the highest in the anterior approach group (P = 0.038), and dysphagia was significantly higher in the combined approach group (P = 0.001). LR (P > 0.999), OS (P = 0.655), and time to both outcomes (log-rank test, OS, P = 0.051, LR, P = 0.187) were not significantly different. Of the 51 patients alive at 3 months, only 19 (37.2%) obtained imaging ≥3 months. Fusion was seen in 11/19 (57.8%) at a median of 8.3 months (interquartile range, 4.6-13.7). Among the anterior corpectomies, the following graft/cage was used: 6 allografts (54.5%), 4 static cages (36.3%), and 1 expandable cage (9.0%), with no difference found in outcomes among the 3 groups.

CONCLUSIONS

The only discernible differences between operative approaches were that patients undergoing an anterior approach had higher rates of new postoperative neurologic deficit, and the combined approach group had higher rates of postoperative dysphagia.

Contemporary trends in the incidence and timing of spinal metastases: A population-based study

Background

Spinal metastases are a significant complication of advanced cancer. In this study, we assess temporal trends in the incidence and timing of spinal metastases and examine underlying patient demographics and primary cancer associations.

Methods

In this population-based retrospective cohort study, health data from 2007 to 2019 in Ontario, Canada were analyzed (n = 37, 375 patients identified with spine metastases). Primary outcomes were annual incidence of spinal metastasis, and time to metastasis after primary diagnosis.

Results

The age-standardized incidence of spinal metastases increased from 229 to 302 cases per million over the 13-year study period. The average annual percent change (AAPC) in incidence was 2.2% (95% CI: 1.4% to 3.0%) with patients aged ≥85 years demonstrating the largest increase (AAPC 5.2%; 95% CI: 2.3% to 8.3%). Lung cancer had the greatest annual incidence, while prostate cancer had the greatest increase in annual incidence (AAPC 6.5; 95% CI: 4.1% to 9.0%). Lung cancer patients were found to have the highest risk of spine metastasis with 10.3% (95% CI: 10.1% to 10.5%) of patients being diagnosed at 10 years. Gastrointestinal cancer patients were found to have the lowest risk of spine metastasis with 1.0% (95% CI: 0.9% to 1.0%) of patients being diagnosed at 10 years.

Conclusions

The incidence of spinal metastases has increased in recent years, particularly among older patients. The incidence and timing vary substantially among different primary cancer types. These findings contribute to the understanding of disease trends and emphasize a growing population of patients who require subspecialty care.

[Imaging Findings of Spinal Metastases with Differential Diagnosis: Focusing on Solitary Spinal Lesion in Older Patients]

If a solitary spinal lesion is found in an older patient, bone metastasis can be primarily considered as the diagnosis. Bone metastasis can occur anywhere, but it mostly occurs in the vertebral body and may sometimes show typical imaging findings, presenting as a single lesion. Therefore, differentiating it from other lesions that mimic bone metastases can be challenging, potentially leading to delayed diagnosis and initiation of primary cancer treatment. This review provides an overview of imaging findings and clinical guidelines for bone metastases and discusses its differences from other diseases that can occur as solitary spinal lesions in older patients.

Quality of life and its selected determinants in the group of patients with surgically treated spinal tumors

Introduction

Spinal metastases are a common manifestation of advanced neoplastic disease. Destructive neoplastic lesions within the axial skeleton cause unrelieved pain and nervous system disorders involving spinal stenosis and other neural structures. The development of new systemic therapies, radiotherapy and minimally invasive spinal surgeries has increased patients' quality of life by minimising pain and neurological disorders due to vertebral neoplastic infiltration. The aim of the study was to assess the patients' quality of life before and after spine stabilisation surgery with spinal cord decompression to relieve the pressure associated with neoplastic destruction.

Materials and Methods

The study involved 115 subjects with spinal metastases in the preoperative period and 3-4 months after the surgery based on the inclusion criteria (metastatic spinal tumour, sensorimotor dysfunction). The data were collected using the following tools: the Rotterdam Symptom Checklist (RSCL-Rotterdam Symptom Checklist), Acceptance Illness Scale (AIS scale), Activities of Daily Living Scale (ADL scale) and Visual Analogue Scale (VAS). The correlation coefficient was calculated using Spearman's rho assuming the significance level at α = 0.05 (p<0.05).

Results

A higher quality of life was found after surgery (p<0.001) in terms of experiencing physical symptoms (30.7 ± 11.96 points before surgery vs. 20.91 ± 13.00 points after surgery) and psychological symptoms (43.98 ± 14.82 points before surgery vs. 31.35 ± 14.86 points after surgery). The activity level of the subjects also improved (p<0.001; 36.56 ± 22.43 points to 43.55 ± 20.40 points). The level of disease acceptance in the study group was higher after the surgery compared to the preoperative assessment. The subjects with a high level of disease acceptance presented a higher quality of life postoperatively. The independence of the subjects in performing everyday activities after the operation influenced the quality of life, in terms of somatic symptoms (p=0.006), mental symptoms (p=0.001) and activity (p<0.001). Along with the improvement in functional capacity, the quality of life in terms of symptoms and activity levels increased.

Conclusion

The study showed that spinal cord decompression surgery improves the quality of life of patients by reducing neurological dysfunction, increasing the acceptance of the disease and the ability to perform activities of daily living (ADL). Sociodemographic variables did not affect the quality of life of the respondents.

Prognostic Factors Associated With Overall Survival in Breast Cancer Patients With Metastatic Spinal Disease

Introduction The spine is the third most frequent site of metastasis, after the lungs and liver, in breast cancer patients. The current treatment modality is based on the prognosis calculated according to multiple clinical features; therefore, multiple scores have been developed to make the therapeutic decision; however, there are no specific scores to take an adequate therapeutic approach in the treatment of vertebral metastases due to breast cancer. The aim of the study is to identify the prognostic factors associated with survival in breast cancer patients with spinal metastatic disease. Methods A retrospective cohort study was carried out at the National Cancerology Institute (INCAN) in Mexico City from January 2011 to December 2017. To this extent, 56 consecutive cases of patients with breast cancer were included. Multiple demographic, laboratory, and clinical variables were taken into account for the survival calculation. Kaplan-Meier graphs and log-rank tests were performed to observe significant differences by subgroups in survival, and Cox regression was used for multivariate analysis. Results Concerning the survival analysis, the patients who presented extra-spinal metastases, an unstable spine, and Frankel grade C had a statistically significantly worse prognosis. In the multivariate analysis, the variables included extra-spinal metastases, age >50 years, spinal instability, serum alkaline phosphatase, and CA 15.3 serum levels, finding statistical significance with a p=0.015. Conclusion Prognostic factors associated with shorter overall survival in breast cancer patients with metastatic spinal disease were the presence of extra-spinal metastases and spinal instability. Additionally, the use of the Tomita and Tokuhashi scores for patients with breast cancer and spinal metastases is not justified at present. The study should be continued with a larger population to decrease biases and obtain a more homogeneous sample, as well as to obtain a personalized score to determine a more efficient treatment for these patients.

Comprehensive evaluation and advanced modification of polymethylmethacrylate cement in bone tumor treatment

Bone tumors are invasive diseases with a tendency toward recurrence, disability, and high mortality rates due to their grievous complications. As a commercial polymeric biomaterial, polymethylmethacrylate (PMMA) cement possesses remarkable mechanical properties, injectability, and plasticity and is, therefore, frequently applied in bone tissue engineering. Numerous positive effects in bone tumor treatment have been demonstrated, including biomechanical stabilization, analgesic effects, and tumor recurrence prevention. However, to our knowledge, a comprehensive evaluation of the application of the PMMA cement in bone tumor treatment has not yet been reported. This review comprehensively evaluates the efficiency and complications of the PMMA cement in bone tumor treatment, for the first time, and introduces advanced modification strategies, providing an objective and reliable reference for the application of the PMMA cement in treating bone tumors. We have also summarized the current research on modifications to enhance the anti-tumor efficacy of the PMMA cement, such as drug carriers and magnetic hyperthermia.

Establishing the Swiss Spinal Tumor Registry (Swiss-STR): a prospective observation of surgical treatment patterns and long-term outcomes in patients with primary and metastatic spinal tumors

Background

Tumors of the vertebral column consist of primary spinal tumors and malignancies metastasizing to the spine. Although primary spine tumors are rare, metastases to the spine have gradually increased over past decades because of aging populations and improved survival for various cancer subtypes achieved by advances in cancer therapy. Metastases to the vertebral column occur in up to 70% of cancer patients, with 10% of patients demonstrating epidural spinal cord compression. Therefore, many cancer patients may face spinal surgical intervention during their chronic illness; such interventions range from simple cement augmentation over decompression of neural elements to extended instrumentation or spinal reconstruction. However, precise surgical treatment guidelines do not exist, likely due to the lack of robust, long-term clinical outcomes data and the overall heterogeneous nature of spinal tumors. Objectives of launching the Swiss Spinal Tumor Registry (Swiss-STR) are to collect and analyze high-quality, prospective, observational data on treatment patterns, clinical outcomes, and health-related quality of life (HRQoL) in adult patients undergoing spinal tumor surgery. This narrative review discusses our rationale and process of establishing this spinal cancer registry.

Methods

A REDCap-based registry was created for the standardized collection of clinical, radiographic, surgical, histological, radio-oncologial and oncological variables, as well as patient-reported outcome measures (PROMs).

Discussion

We propose that the Swiss-STR will inform on the effectiveness of current practices in spinal oncology and their impact on patient outcomes. Furthermore, the registry will enable better categorization of the various clinical presentations of spinal tumors, thereby facilitating treatment recommendations, defining the socio-economic burden on the healthcare system, and improving the quality of care. In cases of rare tumors, the multi-center data pooling will fill significant data gaps to yield better understanding of these entities. Finally, our two-step approach first implements a high-quality registry with efficient electronic data capture strategies across hospital sites in Switzerland, and second follows with potential to expand internationally, thus fostering future international scientific collaboration to further push the envelope in cancer research.

Magnetic Resonance Imaging Evaluation of Bone Metastases Treated with Radiotherapy in Palliative Intent: A Multicenter Prospective Study on Clinical and Instrumental Evaluation Assessment Concordance (MARTE Study)

Metastasis to bone is a common occurrence among epithelial tumors, with a high incidence rate in the Western world. As a result, bone lesions are a significant burden on the healthcare system, with a high morbidity index. These injuries are often symptomatic and can lead to functional limitations, which in turn cause reduced mobility in patients. Additionally, they can lead to secondary complications such as pathological fractures, spinal cord compression, hypercalcemia, or bone marrow suppression. The treatment of bone metastases requires collaboration between multiple healthcare professionals, including oncologists, orthopedists, neurosurgeons, physiatrists, and radiotherapists. The primary objective of this study is to evaluate the correlation between two methods used to assess local control. Specifically, the study aims to determine if a reduction in the volume of bone lesions corresponds to better symptomatic control in the clinical management of patients, and vice versa. To achieve this objective, the study evaluates morphological criteria by comparing pre- and post-radiotherapy treatment imaging using MRI and RECIST 1.1 criteria. MRI without contrast is the preferred diagnostic imaging method, due to its excellent tolerance by patients, the absence of exposure to ionizing radiation, and the avoidance of paramagnetic contrast media side effects. This imaging modality allows for accurate assessment of bone lesions. One of the secondary objectives of this study is to identify potentially useful parameters that can distinguish patients into two classes: "good" and "poor" responders to treatment, as reported by previous studies in the literature. These parameters can be evaluated from the imaging examinations by analyzing morphological changes and radiomic features on different sequences, such as T1, STIR (short tau inversion recovery), and DWI-MRI (diffusion-weighted).

Epidemiology of Surgically Treated Spinal Tumors: A Multicenter Surveillance Study of 9686 Patients from the German Spine Registry (DWG Register)

Tumors of the spine are challenging in terms of diagnoses and interdisciplinary treatment. This study was conducted to evaluate and characterize a large multicenter cohort of surgically treated spine tumor patients.Data of the German Spine Society (DWG) were used to characterize a cohort of all surgically treated spine tumor cases that were registered between 2017 and 2021. Subgroup analysis was performed for tumor entity, tumor localization, height of most severely affected segments, surgical treatment, and demographic parameters.In total, there were 9686 cases, of which 6747 were "malignant", 1942 were "primary benign", 180 were "tumor-like lesions", and 488 were "other" spinal tumors. Subgroups showed differences in number of affected segments as well as localization. There were further significant differences in surgical complication rates (p = 0.003), age (p < 0.001), morbidity (p < 0.001), and duration of surgery (p = 0.004).This is a representative study on spinal tumors from a large spine registry and allows for the epidemiological characterization of surgically treated tumor subgroups and quality control of registry data.

Stereotactic body radiotherapy for spine metastases: a review of 24 Gy in 2 daily fractions

PURPOSE

Stereotactic body radiotherapy (SBRT) has proven to be a highly effective treatment for selected patients with spinal metastases. Randomized evidence shows improvements in complete pain response rates and local control with lower retreatment rates favoring SBRT, compared to conventional external beam radiotherapy (cEBRT). While there are several reported dose-fractionation schemes for spine SBRT, 24 Gy in 2 fractions has emerged with Level 1 evidence providing an excellent balance between minimizing treatment toxicity while respecting patient convenience and financial strain.

METHODS

We provide an overview of the 24 Gy in 2 SBRT fraction regimen for spine metastases, which was developed at the University of Toronto and tested in an international Phase 2/3 randomized controlled trial.

RESULTS

The literature summarizing global experience with 24 Gy in 2 SBRT fractions suggests 1-year local control rates ranging from 83-93.9%, and 1-year rates of vertebral compression fracture ranging from 5.4-22%. Reirradiation of spine metastases that failed prior cEBRT is also feasible with 24 Gy in 2 fractions, and 1-year local control rates range from 72-86%. Post-operative spine SBRT data are limited but do support the use of 24 Gy in 2 fractions with reported 1-year local control rates ranging from 70-84%. Typically, the rates of plexopathy, radiculopathy and myositis are under 5% in those series reporting mature follow up, with no cases of radiation myelopathy (RM) reported in the de novo setting when the spinal cord avoidance structure is limited to 17 Gy in 2 fractions. However, re-irradiation RM has been observed following 2 fraction SBRT. More recently, 2-fraction dose escalation with 28 Gy, with a higher dose constraint to the critical neural tissues, has been reported suggesting improved rates of local control. This regimen may be important in those patients with radioresistant histologies, high grade epidural disease, and/or paraspinal disease.

CONCLUSION

The dose-fractionation of 24 Gy in 2 fractions is well-supported by published literature and is an ideal starting point for centers looking to establish a spine SBRT program.

Imaging of low-energy vertebral fractures

Low-energy vertebral fractures pose a diagnostic challenge for the radiologist due to their often-inadvertent nature and often subtle imaging semiology. However, the diagnosis of this type of fractures can be decisive, not only because it allows targeted treatment to prevent complications, but also because of the possibility of diagnosing systemic pathologies such as osteoporosis or metastatic disease. Pharmacological treatment in the first case has been shown to prevent the development of other fractures and complications, while percutaneous treatments and various oncological therapies can be an alternative in the second case. Therefore, it is necessary to know the epidemiology and typical imaging findings of this type of fractures. The objective of this work is to review the imaging diagnosis of low-energy fractures, with special emphasis on the characteristics that should be outlined in the radiological report to guide a specific diagnosis that favours and optimizes the treatment of patients suffering of low energy fractures.

Unplanned Readmission After Surgery for Cervical Spine Metastases

OBJECTIVE

Patients undergoing surgery for cervical spine metastases are at risk for unplanned readmission due to comorbidities and chemotherapy/radiation. Our objectives were to: 1) report the incidence of unplanned readmission, 2) identify risk factors associated with unplanned readmission, and 3) determine the impact of an unplanned readmission on long-term outcomes.

METHODS

A single-center, retrospective, case-control study was undertaken of patients undergoing cervical spine surgery for metastatic disease between 02/2010 and 01/2021. The primary outcome of interest was unplanned readmission within 6 months. Survival analysis was performed for overall survival (OS) and local recurrence (LR).

RESULTS

A total of 61 patients underwent cervical spine surgery for metastatic disease with the following approaches: 11 (18.0%) anterior, 28 (45.9%) posterior, and 22 (36.1%) combined. Mean age was 60.9 ± 11.2 years and 38 (62.3%) were males. A total of 9/61 (14.8%) patients had an unplanned readmission, 3 for surgical reasons and 6 for medical reasons. No difference was found in demographics, preoperative Karnofsky Performance Scale (P = 0.992), motor strength (P = 0.477), or comorbidities (P = 0.213) between readmitted patients versus not. Readmitted patients had a higher rate of preoperative radiation (P = 0.009). No statistical differences were found in operative time (P = 0.893), estimated blood loss (P = 0.676), length of stay (P = 0.720), discharge disposition (P = 0.279), and operative approach (P = 0.450). Furthermore, no difference was found regarding complications (P = 0.463), postoperative Karnofsky Performance Scale (P = 0.535), and postoperative Modified McCormick Scale (P = 0.586). Lastly, unplanned readmissions were not associated with OS (log-rank; P = 0.094) or LR (log-rank; P = 0.110).

CONCLUSIONS

In patients undergoing cervical spine metastasis surgery, readmission occurred in 15% of patients, 33% for surgical reasons, and 67% for medical reasons. Preoperative radiotherapy was associated with an increased rate of unplanned readmissions, yet readmission had no association with OS or LR.

Patterns of Failure After Stereotactic Body Radiotherapy to Sacral Metastases

AIMS

Stereotactic body radiotherapy (SBRT) is increasingly used to treat sacral metastases. We analysed our centre's local relapse rates and patterns of failure after sacral SBRT and assessed whether using the consensus contouring recommendation (CCR) may have prevented local relapse.

MATERIALS AND METHODS

We conducted a single-centre retrospective review of patients treated with sacral SBRT between February 2012 and December 2021. The cumulative incidence of local relapse, patterns of failure and overall survival were determined. Two investigators reviewed planning computed tomography scans and imaging at relapse to determine if local relapse was potentially preventable with a larger CCR-derived radiotherapy field.

RESULTS

In total, 34 patients received sacral SBRT, with doses ranging from 24 to 40 Gy over three to five fractions. The most frequently used schedule was 30 Gy in three fractions. Common primaries treated included prostate (n = 16), breast (n = 6), lung (n = 3) and renal (n = 3) cancers. The median follow-up was 20 months (interquartile range 13-55 months). The cumulative incidence of local relapse (4/34) was 2.9% (95% confidence interval 0.2-13.2), 6.3% (95% confidence interval 1.1-18.5) and 16.8% (95% confidence interval 4.7-35.4) at 6 months, 1 year and 2 years, respectively. The patterns of failure were local-only (1/34), local and distant (3/34) and distant relapse (10/34). The overall survival was 96.7% (95% confidence interval 90.5-100) and 90.6% (95% confidence interval 78.6-100) at 1 and 2 years, respectively. For prostate/breast primaries, the cumulative incidence of local relapse was 4.5% (95% confidence interval 0.3-19.4), 4.5% (95% confidence interval 0.3-19.4) and 12.5% (95% confidence interval 1.7-34.8) at 6 months, 1 and 2 years, respectively. Twenty-nine cases (85.3%) deviated from the CCR. Sacral relapse was potentially preventable if the CCR was used in one patient (2.9% of the whole cohort and 25% of the relapsed cohort).

DISCUSSION

We have shown excellent local control rates with sacral SBRT, which was largely planned with a margin expansion approach.

Evaluation of different scoring systems for spinal metastases based on a Chinese cohort

INTRODUCTIONS

The spine is one of the most common sites of metastasis for malignancies. This study aimed to compare the predictive performance of seven commonly used prognostic scoring systems for surgically treated spine metastases. It is expected to assist surgeons in selecting appropriate scoring systems to support clinical decision-making and better inform patients.

METHODS

We performed a retrospective study involving 268 surgically treated patients with spine metastases between 2017 and 2020 at a single regional oncology center in China. The revised Tokuhashi, Tomita, modified Bauer, revised Katagiri, van der Linden, Skeletal Oncology Research Group (SORG) nomogram, and SORG machine-learning (ML) scoring systems were externally validated. The area under the curve (AUC) of the receiver operating characteristic curve was used to evaluate sensitivity and specificity at different postoperative time points. The actual survival time was compared with the reference survival time provided in the original publication.

RESULTS

In the present study, the median survival was 16.6 months. The SORG ML scoring system demonstrated the highest accuracy in predicting 90-day (AUC: 0.743) and 1-year survival (AUC: 0.787). The revised Katagiri demonstrated the highest accuracy (AUC: 0.761) in predicting 180-day survival. The revised Katagiri demonstrated the highest accuracy (AUC: 0.779) in predicting 2-year survival. Based on this series, the actual life expectancy was underestimated compared with the original reference survival time.

CONCLUSIONS

None of the scoring systems can perform optimally at all time points and for all pathology types, and the reference survival times provided in the original study need to be updated. A cautious awareness of the underestimation by these models is of paramount importance in relation to current patients.

The Unique Case of Lumbar Dural Metastasis From Cervical Carcinoma on Pembrolizumab

Lumbar metastasis is a rare manifestation of cervical carcinoma which may present as lower extremities symptoms. Immune-checkpoint inhibitors like pembrolizumab, used for the treatment of various metastatic carcinomas, have been linked to Guillain-Barré Syndrome (GBS), which is characterized by ascending weakness and areflexia. A 52-year-old female with metastatic cervical cancer on pembrolizumab for two months presents with lower back pain, progressive bilateral lower extremities ascending weakness, and areflexia of affected limbs. Cerebrospinal fluid analysis showed albuminocytologic disassociation. Spine magnetic resonance imaging showed L4-L5 fracture associated with metastasis and contrast-enhancing adjacent dura and nerve roots. Despite the clinical presentation being consistent with lumbar metastasis, the possibility of masked pembrolizumab-induced GBS presented a therapeutic challenge. Plasmapheresis conferred no clinical improvement and later nerve conduction study was unrevealing for GBS. Subsequently, laminectomy of lumbar vertebrae improved the symptoms. The unique clinical scenario of lumbar dural metastasis from cervical cancer on pembrolizumab, a condition with a similar clinical presentation, is explored in this case.

Characterization and Treatment of Spinal Tumors

The prevalence of spinal tumors is rare in comparison to brain tumors which encompass most central nervous system tumors. Tumors of the spine can be divided into primary and metastatic tumors with the latter being the most common presentation. Primary tumors are subdivided based on their location on the spinal column and in the spinal cord into intramedullary, intradural extramedullary, and primary bone tumors. Back pain is a common presentation in spine cancer patients; however, other radicular pain may be present. Magnetic resonance imaging (MRI) is the imaging modality of choice for intradural extramedullary and intramedullary tumors. Plain radiographs are used in the initial diagnosis of primary bone tumors while Computed tomography (CT) and MRI may often be necessary for further characterization. Complete surgical resection is the treatment of choice for spinal tumors and may be curative for well circumscribed lesions. However, intralesional resection along with adjuvant radiation and chemotherapy can be indicated for patients that would experience increased morbidity from damage to nearby neurological structures caused by resection with wide margins. Even with the current treatment options, the prognosis for aggressive spinal cancer remains poor. Advances in novel treatments including molecular targeting, immunotherapy and stem cell therapy provide the potential for greater control of malignant and metastatic tumors of the spine.

The predictive ability of routinely collected laboratory markers for surgically treated spinal metastases: a retrospective single institution study

PURPOSE

We aimed to identify effective routinely collected laboratory biomarkers for predicting postoperative outcomes in surgically treated spinal metastases and attempted to establish an effective prediction model.

METHODS

This study included 268 patients with spinal metastases surgically treated at a single institution. We evaluated patient laboratory biomarkers to determine trends to predict survival. The markers included white blood cell (WBC) count, platelet count, neutrophil count, lymphocyte count, hemoglobin, albumin, alkaline phosphatase, creatinine, total bilirubin, calcium, international normalized ratio (INR), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR). A nomogram based on laboratory markers was established to predict postoperative 90-day and 1-year survival. The discrimination and calibration were validated using concordance index (C-index), area under curves (AUC) from receiver operating characteristic curves, and calibration curves. Another 47 patients were used as a validation group to test the accuracy of the nomogram. The prediction accuracy of the nomogram was compared to Tomita, revised Tokuhashi, modified Bauer, and Skeletal Oncology Research Group machine-learning (SORG ML).

RESULTS

WBC, lymphocyte count, albumin, and creatinine were shown to be the independent prognostic factors. The four predictive laboratory markers and primary tumor, were incorporated into the nomogram to predict the 90-day and 1-year survival probability. The nomogram performed good with a C-index of 0.706 (0.702-0.710). For predicting 90-day survival, the AUC in the training group and the validation group was 0.740 (0.660-0.819) and 0.795 (0.568-1.000), respectively. For predicting 1-year survival, the AUC in the training group and the validation group was 0.765 (0.709-0.822) and 0.712 (0.547-0.877), respectively. Our nomogram seems to have better predictive accuracy than Tomita, revised Tokuhashi, and modified Bauer, alongside comparable prediction ability to SORG ML.

CONCLUSIONS

Our study confirmed that routinely collected laboratory markers are closely associated with the prognosis of spinal metastases. A nomogram based on primary tumor, WBC, lymphocyte count, albumin, and creatinine, could accurately predict postoperative survival for patients with spinal metastases.

Impact of Obesity on Perioperative Complications on Treatment of Spinal Metastases: A Multicenter Surveillance Study from the German Spine Registry (DWG-Register)

Background  The spine is a common location for the development of primary and metastatic tumors, spinal metastases being the most common tumor in the spine. Spinal surgery in obesity is challenging due to difficulties with anesthesia, intravenous access, positioning, and physical access during surgery. The objective was to investigate the effect of obesity on perioperative complications by discharge in patients undergoing surgery for spinal metastases.

Methods  Retrospective analysis of data from the DWG-register on patients undergoing surgery for metastatic disease in the spine from January 2012 to December 2016. Preoperative variables included obesity (≥ 30 kg/m ² ), age, gender, and smoking status. In addition, the influence of pre-existing medical comorbidity was determined, using the American Society of Anesthesiologists (ASA) score.

Results  In total, 528 decompressions with and without instrumentation undergoing tumor debulking, release of the neural structures, or tumor extirpation in metastatic disease of the spine were identified; 143 patients were obese (body mass index [BMI] ≥ 30 kg/m ² ), and 385 patients had a BMI less than 30 kg/m ² . The mean age in the group with BMI 30 kg/m ² or higher (group 1) was 67 years (56.6%). In the group with BMI less than 30 kg/m ² (group 2), the mean age was 64 years. Most of the patients had preoperatively an ASA score of 3 and 4 (patients with severe general disease). The likelihood of being obese in the logistic regression model seems to be protective by 47.5-fold for blood loss 500 mL or higher. Transfusions occurred in 321/528 (60.7%) patients (group 1, n  = 122 and group 2, n  = 299; p  = 0.04). A total of 19 vertebroplasties with percutaneous stabilization (minimally invasive spine [MIS]), 6 vertebroplasties, and 31 MIS alone were identified. The variables between these groups, with exception of preoperative status (ASA-score; p  = 0.02), remained nonsignificant.

Conclusion  Obese patients were predisposed to have blood loss more than 500 mL more often than nonobese patients undergoing surgery for spinal metastases but with perioperative blood transfusions, invasiveness, nor prolonged hospitalization. Early postoperative mobilization and a low threshold for perioperative venous thromboembolism (VTE) are important in obese patients to appropriately diagnose, treat complications, and minimize morbidity.

Costs Associated With Timely and Delayed Surgical Treatment of Spinal Metastases

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Symptoms caused by spinal metastases are often difficult to distinguish from symptoms caused by non-malignant spinal disease, complicating timely diagnosis, referral and treatment. The ensuing delays may promote the risk of neurological deficits or severe mechanical instability and consequent emergency surgery, leading to poorer prognosis. Presumably, treatment delay may subsequently lead to more health-care consumption and therefore increased average costs of treatment.

METHODS

All patients surgically treated for spinal metastases were included in the current study. Based on the presence of alarming symptoms and urgency of the required intervention, patients were categorized as having received timely or delayed treatment. Pre-surgical, in-hospital, aftercare and total costs were analyzed and compared between the 2 groups.

RESULTS

In total, 299 patients were included, of which 205 underwent timely and 94 delayed treatment. There was no significant difference in pre-surigcal costs (€3.229,13 in the timely treated group vs. €2.528,70 in the delayed treatment group, p = 0.849). The in-hospital costs (€16.738,49 vs. €13.108,81, p < 0.001) and the aftercare costs (€13.950,37 vs. 3.981,93, p < 0.001) were significantly higher for delayed treatment vs. timely treatment, respectively. The total costs were €33.741,71 for delayed treatment and €20.318,52 for timely treatment (p < 0.001).

CONCLUSIONS

The total costs for timely treated patients with spinal metastases are significantly lower compared with patients receiving delayed treatment. Investing in the optimization of referral patterns may therefore reduce the overall pretreatment delay and subsequently increase patient outcome, leading to better clinical outcomes at lower costs.

The 5-Item Modified Frailty Index Independently Predicts Morbidity in Patients Undergoing Instrumented Fusion following Extradural Tumor Removal

Introduction

The management of spinal neoplasia consists of surgical, radiation, and systemic options. Little data exist to guide management based on overall health status, which is particularly challenging when patients who could benefit from surgery may be too frail for it. This study's objective was to evaluate the 5-Item Modified Frailty Index (mFI-5) as a predictor of 30-day morbidity in patients undergoing instrumented resection for metastatic extradural spinal tumors.

Methods

Adults undergoing extradural tumor resection from the 2011 to 2019 National Surgical Quality Improvement Program datasets were identified by Current Procedural Terminology codes 63275-63278 with an adjunct instrumentation code (22840-22843). Patients were classified into frailty levels 0, 1, or 2+ based on mFI-5 scores of 0, 1, or 2-5, respectively. The primary outcome was morbidity. Secondary outcomes were readmission and reoperation. Multivariate modeling was utilized to analyze mFI-5 as a predictor of outcomes. The Akaike information criterion (AIC) was used to compare relative-model-fit based on frailty versus individual comorbidity variables to determine the optimal model. Chi-squared and Fisher's exact tests were used to establish significance between individual complications and frailty.

Results

There were 874 patients. Readmission, reoperation, and morbidity rates were 19.5%, 5.0%, 52.3%, respectively. In multivariate analyses, mFI-5=1 (OR: 1.45, SE: 0.31, p=0.036), mFI-5=2+ (OR: 1.41, SE: 0.40, p=0.036), operative time (OR: 1.18, SE: 0.03, p≤0.001), and chronic steroid use (OR: 1.56, SE: 0.42, p=0.037) independently predicted morbidity. Elective surgery (OR: 0.61) was protective. Frailty did not predict readmission or reoperation. Frailty was found to be significantly associated with respiratory complications, urinary tract infections, cardiac events, and sepsis/septic shock specifically.

Conclusions

mFI-5=1 independently predicted 45% increased odds of morbidity. mFI-5=2+ independently predicted 41% increased odds of morbidity. Further, every 30 additional minutes of operative time predicted 18% increased odds of morbidity, suggesting an increased risk of site-related complication events. Taken together, the mFI-5 serves as a valid predictor of morbidity in patients with extradural tumor undergoing instrumented excision.

Total en bloc spondylectomy for the L5 metastasis of a carcinoid tumor: illustrative case

BACKGROUND

Total en bloc spondylectomy (TES) was designed to achieve oncological complete tumor resection in a vertebral compartment. Because of the special anatomy of the lumbosacral junction, TES procedure at the L5 level is a challenge, and it has been explained in few reports in the literature. Performing TES in the lower lumbar region, as normal, is accomplished by using a combined approach.

OBSERVATIONS

The authors presented the case of a 20-year-old man with an isolated spinal metastasis at the L5 level of carcinoid tumor of jejunum, limited to the vertebral body. Due to good long-term prognosis, after multidisciplinary evaluation the authors decided to treat the patient with TES through a combined posteroanterior approach, with posterior instrumentation and anterior reconstruction. Nine years after surgery, the patient was asymptomatic, with no sign of local recurrence.

LESSONS

TES is a feasible technique to provide long-term survival in a select subgroup of patients, reducing the risk of local recurrence. The authors presented some anatomical and biomechanical factors that must be considered at the lumbosacral region. Despite the high rates of complication associated with TES, most patients benefit from local control provided by the technique.

Prognosis after Palliative Surgery for Patients with Spinal Metastasis: Comparison of Predicted and Actual Survival

Simple Summary

Increased options for cancer treatment have made the prediction of prognosis an important factor in therapeutic decision making. The aim of this study was to assess the clinical significance of prognosis–scoring systems and to identify predictors for 6–month mortality after palliative surgery. The median actual survival period was longer than the predicted life expectancy based on the revised Tokuhashi score and new Katagiri score. However, 21.3% of patients died of cancers within 6 months after palliative surgery. A statistical analysis showed that a higher CRP/albumin ratio (odds ratio: 0.39; cut–off 0.409) and absence of postoperative adjuvant therapy (odds ratio: 7.15) were independent risk factors for poor survival. Our findings suggest the need for careful consideration to determine if palliative surgery is the best option for a patient with these negative prognostic factors, regardless of life expectancy predicted based on a prognosis score.

Abstract

Prediction of prognosis is a key factor in therapeutic decision making due to recent the development of therapeutic options for spinal metastases. The aim of the study was to examine predictive scoring systems and identify prognostic factors for 6–month mortality after palliative surgery. The participants were 75 patients with spinal metastases who underwent palliative surgery and had a minimum follow–up period of 1 year. Associations of actual survival with categories based on the revised Tokuhashi score and new Katagiri score were evaluated. Univariate and multivariate analyses were performed to identify prognostic factors for 6–month mortality after palliative surgery. The median actual survival period was longer than those predicted using the scoring systems. However, 21.3% of patients died of cancers within 6 months after surgery. A higher CRP/albumin ratio (odds ratio: 0.39; cut–off 0.409) and absence of postoperative adjuvant therapy (odds ratio: 7.15) were independent risk factors for 6–month mortality. There was no association of mortality with primary site, severity of sarcopenia, or other biomarkers. These results suggest that careful consideration is needed to determine whether palliative surgery is the best option for patients with a high preoperative CRP/albumin ratio and/or absence of postoperative adjuvant therapy, regardless of predictions made from scoring systems.

Holistic Approach to the Diagnosis and Treatment of Patients with Tumor Metastases to the Spine

The treatment of neoplastic spine metastases requires multi-faceted assessment and an interdisciplinary approach to patients. The metastases do not show specific symptoms but are often the first confirmation of the presence of a primary tumor in a patient. The diagnostic process includes imaging and invasive procedures, e.g., biopsy. It is essential to qualify the patient for an appropriate treatment using dedicated scales. Decompression of the spinal cord is a critical issue to save or restore neurological function in a patient with spine metastases. Surgical treatment ought to meet three criteria: release spinal cord and nerve roots, restore the spine’s anatomical relations, and ensure the internal stabilization of the spine. A good result from surgical treatment enables the continuation of radiotherapy, chemotherapy, hormone therapy, and targeted molecular therapy. Stereotactic radiosurgery and stereotactic body radiotherapy are more effective ways of treating spine metastases than conventional external beam radiotherapy. They allow higher doses of radiation, concentrated precisely at the tumor site. Our review summarizes the established and emerging concepts in the treatment of spine metastases. A holistic approach to the patient enables the selection of the appropriate therapy.

Intramedullary Spinal Cord Metastases from Differentiated Thyroid Cancer, a Case Report

Intramedullary spinal cord metastases (ISCM) are uncommon metastases of the spinal cord. Magnetic resonance (MR) plays an important role in surgical planning when ISCM is suspected in the differential diagnosis. The incidence of ISCM is expected to increase due to the longer survival of cancer patients as well as the widespread use of MR in the diagnosis of neurological syndromes. The management of these patients is controversial because of the multiple clinical presentations and lack of controlled studies on the efficacy of different therapeutic approaches. Increased awareness of this rare entity may lead to an earlier diagnosis with novel imaging approaches at a stage when neurological deficits are reversible. A case of ISCM in a 49-year-old patient with differentiated thyroid cancer is reported.

Expression of CX3CL1 and CCL28 in Spinal Metastases of Lung Adenocarcinoma and Their Correlation with Clinical Features and Prognosis

Lung adenocarcinoma is the most common non-small-cell lung cancer. In this paper, we aim to investigate the expression of chemokine ligand 1 (cx3cl1) and chemokine ligand 28 (CCL28) in spinal metastases of lung adenocarcinoma and their correlation with clinical features and prognosis. We analyzed the clinical data of 40 patients with lung adenocarcinoma and spinal metastases who underwent surgery in our hospital from January 2018 to January 2021 retrospectively. The expression levels of cx3cl1 and CCL28 in bone metastases were detected by immunohistochemistry, and the staining results were sorted and classified. Combined with the follow-up results and clinicopathological data, we statistically analyzed the expression of cx3cl1 and CCL28 in spinal bone metastases and their correlation with prognosis. Among the 40 patients with spinal metastasis of lung adenocarcinoma, 7 cases were strongly positive for cx3cl1, 25 cases were moderately positive, and 8 cases were weakly positive and negative. CCL28 was strongly positive in 9 cases, moderately positive in 26 cases, weakly positive and negative in 5 cases. The expression of cx3cl1 was correlated with ECOG score (P = 0.005) and visceral organ metastasis (P = 0.004), but not with age, sex, and the number of bone metastases (P > 0.05). The expression of CCL28 was correlated with ECOG score (P = 0.022) and visceral organ metastasis (P = 0.003), but not with age, sex, and the number of bone metastases (P > 0.05). The OS of patients with strong cx3cl1 positive was significantly shorter than that of patients with medium positive and weak positive (P < 0.001). The survival time was 10, 7, and 4 months, respectively. The OS of patients with strong positive CCL28 was significantly shorter than that of patients with medium positive and weak positive CCL28 (P = 0.004). The survival time was 12, 8, and 4 months, respectively. Univariate analysis showed that ECOG score (P < 0.001), chemotherapy (P = 0.032), visceral organ metastasis (P = 0.002), cx3cl1 expression (P < 0.001), and CCL28 expression (P = 0.004) were the risk factors of OS. Cox regression analysis showed that the expression of cx3cl1 was an independent risk factor for OS in patients with spinal metastasis of lung adenocarcinoma (P = 0.044). Cx3cl1 and CCL28 were highly/strongly positive in spinal metastases of lung adenocarcinoma. The level of cx3cl1 can be used as an index to judge the clinical prognosis of patients with spinal metastasis of lung adenocarcinoma, which can better reflect the prognosis of patients than CCL28.

The performance of frailty in predictive modeling of short-term outcomes in the surgical management of metastatic tumors to the spine

BACKGROUND CONTEXT

The concept of frailty has become increasingly recognized, and while patients with cancer are at increased risk for frailty, its influence on perioperative outcomes in metastatic spine tumors is uncertain. Furthermore, the impact of frailty can be confounded by comorbidities or metastatic disease burden.

PURPOSE

The purpose of this study was to evaluate the influence of frailty and comorbidities on adverse outcomes in the surgical management of metastatic spine disease.

STUDY DESIGN/SETTING

Retrospective analysis of a nationwide database to include patients undergoing spinal fusion for metastatic spine disease.

PATIENT SAMPLE

A total of 1,974 frail patients who received spinal fusion with spinal metastasis, and 1,975 propensity score matched non-frail patients.

OUTCOME MEASURES

Outcomes analyzed included mortality, complications, length of stay (LOS), nonroutine discharges and costs.

METHODS

A validated binary frailty index (Johns Hopkins Adjusted Clinical Groups) was used to identify frail and non-frail groups, and propensity score-matched analysis (including demographics, comorbidities, surgical and tumor characteristics) was performed. Sub-group analysis of levels involved was performed for cervical, thoracic, lumbar and junctional spine. Multivariable-regression techniques were used to develop predictive models for outcomes using frailty and the Elixhauser Comorbidity Index (ECI).

RESULTS

7,772 patients underwent spinal fusion with spinal metastasis, of which 1,974 (25.4%) patients were identified as frail. Following propensity score matching for frail (n=1,974) and not-frail (n=1,975) groups, frailty demonstrated significantly greater medical complications (OR=1.58; 95% CI 1.33-1.86), surgical complications (OR=1.46; 95% CI 1.15-1.85), LOS (OR=2.65; 95% CI 2.09-3.37), nonroutine discharges (OR=1.79; 95% CI 1.46-2.20) and costs (OR=1.68; 95% CI 1.32-2.14). Differences in mortality were only observed in subgroup analysis and were greater in frail junctional and lumbar spine subgroups. Models using ECI alone (AUC=0.636-0.788) demonstrated greater predictive ability compared to those using frailty alone (AUC=0.633-0.752). However, frailty combined with ECI improved the prediction of increased LOS (AUC=0.811), cost (AUC=0.768), medical complications (AUC=0.723) and nonroutine discharges (AUC=0.718). Predictive modeling of frailty in subgroups demonstrated the greatest performance for mortality (AUC=0.750) in the lumbar spine, otherwise performed similarly for LOS, costs, complications, and discharge across subgroups.

CONCLUSIONS

A high prevalence of frailty existed in the current patient cohort. Frailty contributed to worse short-term adverse outcomes and could be more influential in the lumbar and junctional spine due to higher risk of deconditioning in the postoperative period. Predictions for short term outcomes can be improved by adding frailty to comorbidity indices, suggesting a more comprehensive preoperative risk stratification should include frailty.

Minimally invasive separation surgery for the treatment of spinal metastases with small incision and freehand pedicle screw fixation: the surgical learning curve

BACKGROUND

Minimally invasive separation surgery (MISS) is a safe and effective surgical technique, the current optimal treatment for spinal metastases. However, the learning curve for this technique has not been analyzed. This study aimed to define and analyze the surgical learning curve of MISS for the treatment of spinal metastases with small incision and freehand pedicle screw fixation.

METHODS

A continuous series of 62 patients with spinal metastases who underwent MISS were included. Each patient's operative data were accurately counted. The improvement of the patients' neurological function was followed up after surgery to evaluate the surgical treatment effect. Logarithmic curve-fit regression was used to analyze the surgical learning curve of MISS. The number of cases needed to achieve proficiency was analyzed. Based on this cut-off point, this series of cases was divided into the early phase and later phase groups. The influence of the time sequence of MISS on surgical data and surgical efficacy was analyzed.

RESULTS

The operative time decreased gradually with the number of surgical cases increasing and stabilized after the 20th patient. There was no statistical difference in demographic characteristics and preoperative characteristics between the two groups. The mean operative time in the later phase group was about 39 min shorter than that in the early phase group (mean 227.95 vs. 189.02 min, P = 0.027). However, it did not affect other operative data or the surgical treatment effect.

CONCLUSION

The learning curve of MISS for spinal metastases is not steep. With the increase of surgeons' experience, the operative time drops rapidly and stabilizes within a certain range. MISS can be safely and effectively performed at the beginning of a surgeon's caree.

Frailty Status Is a More Robust Predictor Than Age of Spinal Tumor Surgery Outcomes: A NSQIP Analysis of 4,662 Patients

Objective

The present study aimed to evaluate the effect of baseline frailty status (as measured by modified frailty index-5 [mFI-5]) versus age on postoperative outcomes of patients undergoing surgery for spinal tumors using data from a large national registry.

Methods

The National Surgical Quality Improvement Program database was used to collect spinal tumor resection patients’ data from 2015 to 2019 (n = 4,662). Univariate and multivariate analyses for age and mFI-5 were performed for the following outcomes: 30-day mortality, major complications, unplanned reoperation, unplanned readmission, hospital length of stay (LOS), and discharge to a nonhome destination. Receiver operating characteristic (ROC) curve analysis was used to evaluate the discriminative performance of age versus mFI-5.

Results

Both univariate and multivariate analyses demonstrated that mFI-5 was a more robust predictor of worse postoperative outcomes as compared to age. Furthermore, based on categorical analysis of frailty tiers, increasing frailty was significantly associated with increased risk of adverse outcomes. ‘Severely frail’ patients were found to have the highest risk, with odds ratio 16.4 (95% confidence interval [CI],11.21–35.44) for 30-day mortality, 3.02 (95% CI, 1.97–4.56) for major complications, and 2.94 (95% CI, 2.32–4.21) for LOS. In ROC curve analysis, mFI-5 score (area under the curve [AUC] = 0.743) achieved superior discrimination compared to age (AUC = 0.594) for mortality.

Conclusion

Increasing frailty, as measured by mFI-5, is a more robust predictor as compared to age, for poor postoperative outcomes in spinal tumor surgery patients. The mFI-5 may be clinically used for preoperative risk stratification of spinal tumor patients.

Risk factors for wound-related complications after surgical stabilization of spinal metastases with a special focus on the effect of postoperative radiation therapy

BACKGROUND

Advancements in the field of oncological therapies during the last decades have led to a significantly prolonged survival of cancer patients. This has led to an increase in the incidence of spinal metastases. The purpose of this study was to assess risk factors for wound-related complications after surgical stabilization of spinal metastases with a special focus on the effect of postoperative RT and its timing.

METHODS

Patients who had been treated for metastatic spine disease by surgical stabilization followed by radiotherapy between 01/2012 and 03/2019 were included and a retrospective chart review was performed.

RESULTS

Of 604 patients who underwent stabilizing surgery for spinal metastases, 237 patients (mean age 66 years, SD 11) with a mean follow-up of 11 months (SD 7) were eligible for further analysis. Forty-one patients (17.3%) had wound-related complications, 32 of them before and 9 after beginning of the RT. Revision surgery was necessary in 26 patients (11.0%). Body weight (p = 0.021), obesity (p = 0.018), ASA > 2 (p = 0.001), and start of radiation therapy within 21 days after surgery (p = 0.047) were associated with an increased risk for wound complications. Patients with chemotherapy within 3 weeks of surgery (12%) were more likely to have a wound-related surgical revision (p = 0.031).

CONCLUSION

Body weight, obesity and ASA > 2 were associated with an increased risk for wound complications. Patients with chemotherapy within 3 weeks of the surgery were more likely to have a wound-related revision surgery. Patients who had begun radiation therapy within 21 days after surgery were more likely to have a wound complication compared to patients who waited longer.

Central Nervous System Metastases

The proportion of patients developing central nervous system (CNS) metastasis is increasing. Most are identified once symptomatic. Surgical resection is indicated for solitary or symptomatic brain metastases, separation surgery for compressive radioresistant spinal metastases, and instrumentation for unstable spinal lesions. Surgical biopsies are performed when histological diagnoses are required. Stereotactic radiosurgery is an option for limited small brain metastases and radioresistant spinal metastases. Whole-brain radiotherapy is reserved for extensive brain metastases and leptomeningeal disease with approaches to reduce cognitive side effects. Radiosensitive and inoperable spinal metastases typically receive external beam radiotherapy. Systemic therapy is increasingly being utilized for CNS metastases.

Role of radiofrequency ablation and cement injection for pain control in patients with spinal metastasis

Background

The study aimed to investigate the effects and reliability of simultaneous vertebroplasty and radiofrequency ablation or radiofrequency ablation applied alone for pain control in patients with painful spine metastasis, and to investigate the effect of preventing tumor spread in long-term follow-up.

Methods

Patients with painful vertebrae metastasis in the Afyonkarahisar Health Sciences University, Medical Faculty, Hospital Neurosurgery Clinic between 01.01.2015 and 01.06.2020 were recruited. They were divided into groups according to the surgical procedures applied. Group 1 included 26 patients who underwent radiofrequency ablation only, and group 2 included 40 patients who underwent vertebroplasty with radiofrequency ablation. Computed tomography and magnetic resonance imaging were performed in all patients pre-operation. The patients were followed for at least 6 months. Magnetic resonance imaging was performed at the end of the 6th month in neurologically stable patients. The metastatic lesion, pain, and quality of life were evaluated with Visual Analog Scale and Oswestry Disability Survey before and after the procedure.

Results

The mean VAS score before the procedure was 8.3 ± 1.07 in the RFA group, and a statistically significant difference was observed in VAS scores at all post-procedural measurement time-points (p < 0.001). The pain scores decreased at a rate of 58.8 and 69.6% of patients showed significant improvements in the QoL in the RFA-only group. The mean VAS score was 7.44 ± 1.06 in group RFA + VP before the procedure; the difference in the mean VAS scores was statistically significant at all measurement time-points after the procedure (p < 0.001). The mean pre-treatment Oswestry Index (to assess the QoL) was 78.50% in the RFA + VP group, which improved to 14.2% after treatment.

Conclusion

Ablation + vertebroplasty performed to control palliative pain and prevent tumor spread in patients with painful vertebral metastasis is more successful than vertebroplasty performed alone.

Radiographic diagnosis of osteoporotic vertebral fractures. An updated review

The radiological diagnosis of osteoporotic vertebral fractures (OVFs) is of major importance considering its therapeutic and prognostic implications. Both radiologists and clinicians have the opportunity to diagnose OVFs in daily clinical practice due to the widespread use of spine and chest radiography. However, several studies have reported an under-diagnosis of OVFs, particularly by a lack of consensus on the diagnostic criteria. Therefore, up-to-date knowledge of the most relevant approaches for the diagnosis of OVFs is necessary for many physicians. This article aims to review the most commonly used classification systems in the diagnosis of OVFs based on conventional radiography. We discuss their rationale, advantages and limitations, as well as their utility according to the context. This review will provide a concise yet useful understanding of the typology of OVFs, their clinical significance and prognosis. Finally, we include anatomical variations that can be confused with OVFs by non-experts.

Cement-Augmented Carbon Fiber-Reinforced Pedicle Screw Instrumentation for Spinal Metastases: Safety and Efficacy

OBJECTIVE

To investigate the complication rates and long-term implant failure rates in a monocentric study of a consecutive cohort of patients with thoracolumbar spinal metastases after posterior instrumentation with a fenestrated carbon fiber-reinforced poly-ether-ether-ketone (CFRP) pedicle screw system.

METHODS

We retrospectively reviewed demographics, Karnofsky Performance Status Scale scores, complications, and implant failure rates.

RESULTS

Between June 2016 and November 2019, 51 consecutive patients underwent cement-augmented CFRP pedicle screw instrumentation at our institution. Mean age was 68 years (standard deviation 10.5), the median preoperative Karnofsky Performance Status Scale of 80 increased to 90 postoperatively (P = 0.471). Most common primary entities were breast (25.5%), lung (15.7%), and prostate (13.7%) cancers. Of 428 placed screws, 293 (68.5%) were augmented with polymethylmethacrylate, a mean 6 per patient (standard deviation ±2). Screws were inserted via a minimally invasive system technique in 54.9% of cases. In total, 11.8% of patients had immediate postoperative sequelae related to the cement. Pulmonary cement embolisms were noted in 3 patients, 2 had paravertebral extravasation, and 1 had an embolism into a segmental artery. Of these 6, 2 patients with pulmonary embolisms reported related symptoms. Follow-up was available for 80.4%. After a mean 9.8 months, screw loosening was noted in 11.8% of cases on computed tomography, although it was asymptomatic in all but 1 patient. Screw pull-out did not occur. Neither cement-related (P = 0.353) nor general complication rates (P = 0.507) differed significantly between open and minimally invasive system techniques.

CONCLUSIONS

Percutaneous cement-augmented CFRP pedicle screw instrumentation facilitates artifact-reduced postoperative imaging, while maintaining a risk profile and implant failure rates comparable to conventional metallic instrumentation.

Inclusion of Frailty Improves Predictive Modeling for Postoperative Outcomes in Surgical Management of Primary and Secondary Lumbar Spine Tumors

BACKGROUND

Malignant spinal tumors are common, continually increasing in incidence as a function of improved survival times for patients with cancer. Using predictive analytics and propensity score matching, we evaluated the influence of frailty on postoperative complications compared with age in patients with malignant neoplasms of the lumbar spine.

METHODS

We used the Nationwide Readmissions Database from 2016 and 2017 to identify patients with malignant neoplasms of the lumbar spine who received a fusion procedure. Patient frailty was queried using the Johns Hopkins Adjusted Clinical Groups. Propensity score matching for age, sex, Charlson Comorbidity Index, surgical approach, and number of levels fused was implemented between frail and nonfrail patients, identifying 533 frail patients and 538 nonfrail patients. The area under the curve (AUC) of each ROC served as a proxy for model performance.

RESULTS

Frail patients reported significantly higher inpatient lengths of stay, costs, infection, posthemorrhagic anemia, and urinary tract infections (P < 0.05). In addition, frail patients were more often discharged to skilled nursing facilities and short-term hospitals compared with nonfrail patients (P < 0.0001). Regression models for mortality (AUC = 0.644), nonroutine discharge (AUC = 0.600), and acute infection (AUC = 0.666) were improved when using frailty as the primary predictor. These models were also improved using frailty when predicting 30-day readmission and 90-day hardware failure.

CONCLUSIONS

Frailty demonstrated a significant relationship with increased postoperative patient complications, length of stay, costs, and acute complications in patients receiving fusion following resection of a malignant neoplasm of the lumbar spine region. Frailty demonstrated better predictive validity of outcomes compared with patient age.

The Early Results of Vertebral Pathological Compression Fracture of Extra- nodal Lymphoma with HIV-positive Patients Treated by Percutaneous Kyphoplasty

BACKGROUND

Vertebral pathological compression fracture involving extra-nodal lymphoma impacts negatively on the quality of life of HIV-positive patients. The choice of a safe and effective approach to palliative care in this condition remains a challenge.

OBJECTIVE

The purpose of this study was to investigate the safety and efficacy of percutaneous kyphoplasty (PKP) in the treatment of vertebral pathological compression fracture of extra-nodal lymphoma in HIV-positive patients.

METHODS

A retrospective analysis, from January 2016 to August 2019, was performed on 7 HIVpositive patients, 3 males and 4 females, with extra-nodal lymphoma with a vertebral pathological compression fracture. The patients were treated using percutaneous kyphoplasty in our hospital. Preoperative assessment of the patients was conducted regarding their hematological profile, biochemical indicators, liver and kidney function, blood coagulation function, CD4+T lymphocyte count and viral load. Subsequently, the patients were placed on highly active antiretroviral therapy (HAART) and rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP) regimen. Besides, antibiotics, nutritional support and immune-modulating drugs were also administered, rationally. Postoperatively, the height of the anterior edge of the injured vertebrae, Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) values were evaluated. Patients were also monitored for any complications related to the operation.

RESULTS

The average CD4+T cell count for the patients was 164 (range 114 ~247 / ul), while the viral load was 26,269 (range 5,765 ~82,321 copies/ul). All patients received nutritional and immune support and registered significant improvements in the levels of ALB and Hb (P<0.05). In all cases, the operation was uneventful with neither cement leakage nor toxic reactions observed. Similarly, no opportunistic infections, other complications or deaths were reported. The height of the anterior vertebral body and the ODI score of the injured vertebrae were significantly improved immediately after surgery (P<0.05). Compared to the preoperative VAS (7.71±1.11), postoperative values were significantly reduced immediately after surgery (3.85±0.90) and at 2 weeks, 1 month and 6 months post-surgery: 2.71±0.76, 3.29±1.11, and 4.00±0.82, respectively (P<0.01).

CONCLUSION

Supported with appropriate perioperative treatment measures, PKP is safe and effective in the treatment of pathological vertebral compression fracture due to extra-nodal lymphoma in HIV-positive patients.

A novel approach to evaluate the effects of artificial bone focal lesion on the three-dimensional strain distributions within the vertebral body

The spine is the first site for incidence of bone metastasis. Thus, the vertebrae have a high potential risk of being weakened by metastatic tissues. The evaluation of strength of the bone affected by the presence of metastases is fundamental to assess the fracture risk. This work proposes a robust method to evaluate the variations of strain distributions due to artificial lesions within the vertebral body, based on in situ mechanical testing and digital volume correlation. Five porcine vertebrae were tested in compression up to 6500N inside a micro computed tomography scanner. For each specimen, images were acquired before and after the application of the load, before and after the introduction of the artificial lesions. Principal strains were computed within the bone by means of digital volume correlation (DVC). All intact specimens showed a consistent strain distribution, with peak minimum principal strain in the range -1.8% to -0.7% in the middle of the vertebra, demonstrating the robustness of the method. Similar distributions of strains were found for the intact vertebrae in the different regions. The artificial lesion generally doubled the strain in the middle portion of the specimen, probably due to stress concentrations close to the defect. In conclusion, a robust method to evaluate the redistribution of the strain due to artificial lesions within the vertebral body was developed and will be used in the future to improve current clinical assessment of fracture risk in metastatic spines.

How to Target Spinal Metastasis in Experimental Research: An Overview of Currently Used Experimental Mouse Models and Future Prospects

The spine is one of the organs that is most affected by metastasis in cancer patients. Since the control of primary tumor is continuously improving, treatment of metastases is becoming one of the major challenges to prevent cancer-related death. Due to the anatomical proximity to the spinal cord, local spread of metastasis can directly cause neurological deficits, severely limiting the patient’s quality of life. To investigate the underlying mechanisms and to develop new therapies, preclinical models are required which represent the complexity of the multistep cascade of metastasis. Current research of metastasis focuses on the formation of the premetastatic niche, tumor cell dormancy and the influence and regulating function of the immune system. To unveil whether these influence the organotropism to the spine, spinal models are irreplaceable. Mouse models are one of the most suitable models in oncologic research. Therefore, this review provides an overview of currently used mouse models of spinal metastasis. Furthermore, it discusses technical aspects clarifying to what extend these models can picture key steps of the metastatic process. Finally, it addresses proposals to develop better mouse models in the future and could serve as both basis and stimulus for researchers and clinicians working in this field.

Comprehensive surgical treatment strategy for spinal metastases

The management of patients with spinal metastases (SM) requires a multidisciplinary team of specialists involved in oncological care. Surgical management has evolved significantly over the recent years, which warrants reevaluation of its role in the oncological treatment concept. Any patient with a SM was screened for study inclusion. We report baseline characteristics, surgical procedures, complication rates, functional status and outcome of a large consecutive cohort undergoing surgical treatment according to an algorithm. 667 patients underwent 989 surgeries with a mean age of 65 years (min/max 20–94) between 2007 and 2018. The primary cancers mostly originated from the prostate (21.7%), breast (15.9%) and lung (10.0%). Surgical treatment consisted of dorsoventral stabilization in 69.5%, decompression without instrumentation in 12.5% and kyphoplasty in 18.0%. Overall survival reached 18.4 months (95% CI 9.8–26.9) and the median KPS increased by 10 within hospital stay. Surgical management of SMs should generally represent the first step of a conclusive treatment algorithm. The need to preserve long-term symptom control and biomechanical stability requires a surgical strategy currently not supported by level I evidence.

Percutaneous thermal ablation of sacral metastases: Assessment of pain relief and local tumor control

PURPOSE

To retrospectively report on safety, pain relief and local tumor control achieved with percutaneous ablation of sacral bone metastases.

MATERIALS AND METHODS

From February 2009 to June 2020, 23 consecutive patients (12 women and 11 men; mean age, 60±8 [SD] years; median, 60; range: 48-80 years) with 23 sacral metastases underwent radiofrequency (RFA) or cryo-ablation (CA), with palliative or curative intent at our institution. Patients' demographics and data pertaining to treated metastases, procedure-related variables, safety, and clinical evolution following ablation were collected and analyzed. Pain was assessed with numerical pain rating scale (NPRS).

RESULTS

Sixteen (70%) patients were treated with palliative and 7 (30%) with curative intent. Mean tumor diameter was 38±19 (SD) mm (median, 36; range: 11-76). External radiation therapy had been performed on five metastases (5/23; 22%) prior to ablation. RFA was used in 9 (39%) metastases and CA in the remaining 14 (61%). Thermo-protective measures and adjuvant bone consolidation were used whilst treating 20 (87%) and 8 (35%) metastases, respectively. Five (22%) minor complications were recorded. At mean 31±21 (SD) (median, 32; range: 2-70) months follow-up mean NPRS was 2±2 (SD) (median, 1; range: 0-6) vs. 5±1 (median, 5; range: 4-8; P<0.001) at the baseline. Three metastases out of 7 (43%) undergoing curative ablation showed local progression at mean 4±4 (SD) (median, 2; range: 1-8) months follow-up.

CONCLUSION

Percutaneous ablation of sacral metastases is safe and results in significant long-lasting pain relief. Local tumor control seems sub-optimal; however, further investigations are needed to confirm these findings due to paucity of data.

A Comparative Study Between Minimally Invasive Spine Surgery and Traditional Open Surgery for Patients With Spinal Metastasis

STUDY DESIGN

A retrospective study was conducted.

OBJECTIVE

This study aims to compare the perioperative outcomes of minimal invasive spine surgery (MISS) and traditional open surgery (TOS) for thoracolumbar spine metastasis.

SUMMARY OF BACKGROUND DATA

TOS for metastatic spinal tumors has many disadvantages, such as significant blood loss and high complication rate. MISS may change the treatment modality, but its safety and efficacy for spinal metastasis are lacking.

METHODS

We retrospectively reviewed clinical data from 154 consecutive patients registered in our institute who underwent separation surgery for spinal metastases from January 2017 to December 2019. Forty-nine patients received MISS and 105 patients had TOS. The demographic and perioperative data were collected and compared between two approaches.

RESULTS

There were no significant differences in baseline characteristics between the MISS and TOS group, except the sex (P = 0.04). The mean intraoperative blood loss in MISS group was lower than that in TOS group (748.57 vs. 950.48 mL, P = 0.039). The operative time was comparable between both groups (mean 213.45 vs. 221.03 minutes, P = 0.78). The postoperative drainage before discharge in MISS group was remarkably less than that in TOS group (mean 494.02 vs. 1099.10 mL, P = 0.0004). As compared to TOS group, patients in MISS group had lower complication rate, although the difference is not significant (9.52% vs. 6.12%, P = 0.55). The infection rate of MISS group was two-fold lower than that in the TOS group, although the difference is not significant (P = 0.43). The mean hospital stay of MISS group is 7.35 days, which is significantly shorter than TOS group (9.94 days, P = 0.0007). Patients in both groups exhibited similar postoperative neurological outcomes.

CONCLUSION

MISS is a safe and effective technique that could be considered the optimal treatment for patients with spinal metastasis and myelopathy and thus is an excellent alternative in managing thoracolumbar spine metastasis.

LEVEL OF EVIDENCE

3.

The role of radiography in the study of spinal disorders

Despite the growing use of computed tomography (CT) and magnetic resonance imaging (MRI) in the study of spinal disorders, radiography still plays an important role in many conditions affecting the spine. However, the study and interpretation of spine radiograph is receiving less attention and radiologists are increasingly unfamiliar with the typical findings in normal and pathologic conditions of the spine. The aim of this article is to review the radiologic indications of radiograph in different pathologic conditions that affect the spine, including congenital, traumatic, degenerative, inflammatory, infectious and tumour disorders, as well as their main radiographic manifestations.

A Novel Prediction Tool for Overall Survival of Patients Living with Spinal Metastatic Disease

OBJECTIVE

To identify the significant prognostic factors for overall survival in patients with spinal metastases and to establish an online widget for predicting survival with an interactive visual approach.

METHODS

Patients operated for spinal metastases between 2010 and 2018 were retrospectively enrolled and were randomly divided into training and validation samples with a ratio of 7:3. Patients' characteristics were analyzed with univariate and multivariate Cox analyses to identify independent prognostic factors basing on the training sample. A shiny web tool was developed by transforming the fitted multivariable Cox model into a visual interface. Time-dependent area under the curve plot and calibration curve were generated to assess the discrimination ability and consistency of the novel model, both for the training and validation samples.

RESULTS

A total of 265 consecutive patients were finally included, with 185 in the training sample and 80 in the validation sample. The primary tumor types, lesion site of metastasis, visceral metastasis, Frankel grade, operation category, number of surgical segments, and the preoperative percentage of lymphocyte were demonstrated to be significantly associated with overall survival. A novel shiny model (https://yang1209xg.shinyapps.io/predictspinalmetastasis/) that could provide predicted survival curve and median survival time was established, with favorable discrimination ability and consistency between predicted and actual survival both in internal and external data, according to time-dependent area under the curve plots and calibration curves.

CONCLUSIONS

A user-friendly shiny app with favorable discrimination ability and consistency was released online for predicting the survival of patients with spinal metastases. A continuous survival curve and the predicted median survival time are available to guide the treatment planning.