Tumors of the spine

Machine Learning in Spine Oncology: A Narrative Review

STUDY DESIGN

Narrative Review.

OBJECTIVE

Machine learning (ML) is one of the latest advancements in artificial intelligence used in medicine and surgery with the potential to significantly impact the way physicians diagnose, prognose, and treat spine tumors. In the realm of spine oncology, ML is utilized to analyze and interpret medical imaging and classify tumors with incredible accuracy. The authors present a narrative review that specifically addresses the use of machine learning in spine oncology.

METHODS

This study was conducted in accordance with the Preferred Reporting Items of Systematic Reviews and Meta-Analysis (PRISMA) methodology. A systematic review of the literature in the PubMed, EMBASE, Web of Science, Scopus, and Cochrane Library databases since inception was performed to present all clinical studies with the search terms '[[Machine Learning] OR [Artificial Intelligence]] AND [[Spine Oncology] OR [Spine Cancer]]'. Data included studies that were extracted and included algorithms, training and test size, outcomes reported. Studies were separated based on the type of tumor investigated using the machine learning algorithms into primary, metastatic, both, and intradural. A minimum of 2 independent reviewers conducted the study appraisal, data abstraction, and quality assessments of the studies.

RESULTS

Forty-five studies met inclusion criteria out of 480 references screened from the initial search results. Studies were grouped by metastatic, primary, and intradural tumors. The majority of ML studies relevant to spine oncology focused on utilizing a mixture of clinical and imaging features to risk stratify mortality and frailty. Overall, these studies showed that ML is a helpful tool in tumor detection, differentiation, segmentation, predicting survival, predicting readmission rates of patients with either primary, metastatic, or intradural spine tumors.

CONCLUSION

Specialized neural networks and deep learning algorithms have shown to be highly effective at predicting malignant probability and aid in diagnosis. ML algorithms can predict the risk of tumor recurrence or progression based on imaging and clinical features. Additionally, ML can optimize treatment planning, such as predicting radiotherapy dose distribution to the tumor and surrounding normal tissue or in surgical resection planning. It has the potential to significantly enhance the accuracy and efficiency of health care delivery, leading to improved patient outcomes.

Role of Posterior Carbon Fiber Implants in Spine Tumor Surgery

STUDY DESIGN

Narrative Review.

OBJECTIVE

The management of spinal tumors requires a multi-disciplinary approach including surgery, radiation, and systemic therapy. Surgical approaches typically require posterior segmental instrumentation to maintain long-term spinal stability. Carbon fiber reinforced pedicle screws (CFRP) are increasingly used in the oncologic setting due to reductions in both imaging artifacts and radiotherapy perturbations compared to titanium implants. We performed a review of the literature and highlight advantages and future areas of study for CFRP.

METHODS

We performed a systematic review of the literature using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and identified 10 articles including 573 patients. Across all studies we reviewed patient demographics, tumor types treated, hardware-related features, complication rates, recurrence, survival, and follow-up.

RESULTS

Across 10 studies, a total of 1371 screws placed. Surgical and non-surgical complications were reported in 18.3% of patients. Disease progression at the surgical site was detected in 7.3% of patients. There was no significant difference in clinical or hardware complications between CFRP or titanium implants. The most frequent complication attributable to implanted CFRP hardware included screw breakage in 2.4% and loosening in 1.7% of patients, respectively.

CONCLUSION

CFRP provide a unique tool in the setting of spinal oncology. With a safety profile comparable to titanium, we review the documented advantages of CFRP posterior implants compared to titanium, while also addressing their current limitations. Additionally, we highlight several areas of future research to identify the optimal patients who will achieve the greatest benefit of CFRP.

Spinal schwannoma: Limitations of CT imaging

Spinal schwannomas are benign lesions that most commonly appear in the lumbar and thoracic regions of the spine. Although computed tomography (CT) scans are often used to assess spinal conditions, they are ineffective at detecting soft tissue abnormalities. This case is for a 49-year-old female who experienced a gradual loss of sensation and strength in her lower extremities, along with increased urinary urgency, over six weeks. In addition, mid-back pain has been present for one year. Initially, a CT scan was done and did not show any significant findings, which suggested the absence of a spinal abnormality. However, magnetic resonance imaging (MRI) revealed an intradural extramedullary lesion causing spinal cord compression. The patient successfully underwent surgery to remove the tumor, and histological analysis confirmed it as spinal schwannoma. This case underlines the diagnostic limitations of CT imaging for spinal lesions and illustrates the superior accuracy of MRI. Thus, a negative CT should not halt further diagnostic evaluation when symptoms persist.

Advances in imaging modalities for spinal tumors

The spinal cord occupies a narrow region and is tightly surrounded by osseous and ligamentous structures; spinal tumors can damage this structure and deprive patients of their ability to independently perform activities of daily living. Hence, imaging is vital for the prompt detection and accurate diagnosis of spinal tumors, as well as determining the optimal treatment and follow-up plan. However, many clinicians may not be familiar with the imaging characteristics of spinal tumors due to their rarity. In addition, spinal surgeons might not fully utilize imaging for the surgical planning and management of spinal tumors because of the complex heterogeneity of these lesions. In the present review, we focus on conventional and advanced spinal tumor imaging techniques. These imaging modalities include computed tomography, positron emission tomography, digital subtraction angiography, conventional and microstructural magnetic resonance imaging, and high-resolution ultrasound. We discuss the advantages and disadvantages of conventional and emerging imaging modalities, followed by an examination of cutting-edge medical technology to complement current needs in the field of spinal tumors. Moreover, machine learning and artificial intelligence are anticipated to impact the application of spinal imaging techniques. Through this review, we discuss the importance of conventional and advanced spinal tumor imaging, and the opportunity to combine advanced technologies with conventional modalities to better manage patients with these lesions.

Current state of spinal nerve sheath tumor management and future advances

Nerve sheath tumors are the most common tumors of the spine after meningiomas. They include schwannomas, neurofibroma, and malignant peripheral nerve sheath tumors. These can arise sporadically or in association with tumor predisposition syndromes, including neurofibromatosis type 1, neurofibromatosis type 2, and schwannomatosis. Though surgery is the traditional mainstay of treatment for these tumors, the discovery of the genetic and molecular basis of these diseases in recent decades has prompted investigation into targeted therapies. Here, we give a clinical overview of spinal nerve sheath tumors, their imaging features, current management practices, and explore ongoing advances in systemic therapies.

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.

Unusual Presentation of Thoracic Chordoma with Spinal Epidural Hematoma: A Rare Case Report and PRISMA-Driven Systematic Review

A chordoma is a slow growing, locally invasive, low-grade tumor belonging to the sarcoma family. It mainly affects the sacrum and skull base. We present a case of thoracic chordoma initially presented with epidural hematoma (EDH), which is a rare clinical entity. We reported this case, and also performed a PRISMA-driven systematic review to summary the similar cases in the literature. This review includes the clinical characteristics and outcome of thoracic chordoma. Our case involves a 60-year-old male who, despite no history of trauma, presented with acute paraparesis. An epidural hematoma was identified at T6 level, leading to a surgical intervention involving T4-6 laminectomy and fixation. Six months subsequent to surgery, the patient experienced progressive lower limb weakness and spasticity. Computed tomography (CT) exhibited erosion of T6 and an associated aggressive mass. Magnetic resonance imaging (MRI) revealed a large heterogenous soft tissue mass arising from the vertebral body and right pedicle of D6, protruding in the epidural space and compressing the spinal cord focally at this level. The mass measured approximately 5 × 4 × 3.5 cm. Magnetic resonance myelography indicated a filling defect at T5-6 level, confirming the intraspinal location of the soft tissue lesion. Complete excision of the mass confirmed the diagnosis of thoracic chordoma. Postoperative follow-up demonstrated notable improvement in the lower limb spasticity and paraparesis, and the patient started adjuvant radiotherapy. This case underscores the importance of maintaining a high index of suspicion when evaluating presentations resembling EDH.

Revision total en bloc spondylectomy for a recurrent aggressive vertebral haemangioma of the thoracic spine causing progressive thoracic myelopathy with segmental kyphosis

Vertebral haemangiomas are common amongst primary benign tumours of the spine, usually asymptomatic and discovered incidentally, whereby symptomatic cases are rare. Aggressive vertebral haemangiomas, occurring even less frequently, are characterized by their expansion, resulting in pain and neural compression symptoms. Depending on presentation and severity, several treatment options exist, and when causing progressive neurological deficit, surgical decompression and resection is warranted. Despite local recurrence being rare, regular follow-ups to detect recurrence are advised. In case of recurrent aggressive vertebral haemangiomas, however, subsequent treatment strategy usually depends on a case-by-case consideration, whereby reports in the literature are lacking. We describe a case of a recurrent aggressive vertebral haemangiomas of the thoracic spine in a 20-year-old male causing progressive thoracic myelopathy with segmental kyphosis, treated with a revision total en bloc spondylectomy and a multilevel fixation with vertebral column reconstruction using radiolucent instrumentation.

State-of-the-Art and New Treatment Approaches for Spinal Cord Tumors

Spinal cord tumors, though rare, present formidable challenges in clinical management due to their intricate nature. Traditional treatment modalities like surgery, radiation therapy, and chemotherapy have been the mainstay for managing these tumors. However, despite significant advancements, challenges persist, including the limitations of surgical resection and the potential side effects associated with radiation therapy. In response to these limitations, a wave of innovative approaches is reshaping the treatment landscape for spinal cord tumors. Advancements in gene therapy, immunotherapy, and targeted therapy are offering groundbreaking possibilities. Gene therapy holds the potential to modify the genes responsible for tumor growth, while immunotherapy harnesses the body's own immune system to fight cancer cells. Targeted therapy aims to strike a specific vulnerability within the tumor cells, offering a more precise and potentially less toxic approach. Additionally, novel surgical adjuncts are being explored to improve visualization and minimize damage to surrounding healthy tissue during tumor removal. These developments pave the way for a future of personalized medicine for spinal cord tumors. By delving deeper into the molecular makeup of individual tumors, doctors can tailor treatment strategies to target specific mutations and vulnerabilities. This personalized approach offers the potential for more effective interventions with fewer side effects, ultimately leading to improved patient outcomes and a better quality of life. This evolving landscape of spinal cord tumor management signifies the crucial integration of established and innovative strategies to create a brighter future for patients battling this complex condition.

Patient-Reported Outcomes for Spine Oncology: A Narrative Review

Spine tumors, both primary and metastatic, impose significant morbidity and mortality on patients and physicians. Patient-reported outcomes are valuable tools to assess a patient's impression of their health status and enhance communication between physicians and patients. Various spine generic patient-reported outcome tools have traditionally been used but have not been validated in the spine tumor patient population. The Spine Oncology Study Group Outcome Questionnaire, which is disease-specific for the metastatic spine patient population, has been shown to have strong validity, even across multiple languages. Patient-Reported Outcomes Measurement Information System, which has recently been developed, employs computerized adaptive testing to assess multiple health domains. It has been shown to capture information in both generic and specific questionnaires and has the potential to be used as a universal tool in the spine oncology patient population. Further long-term studies, as well as, cross-cultural adaptations, are needed to validate Patient-Reported Outcomes Measurement Information System's applicability and effectiveness.

Does Preoperative Bilsky Score Predict Outcome Following Surgical Resection of Primary Tumors of the Spine?

OBJECTIVE

In patients undergoing surgery for primary bone tumors of the spine, we sought to compare Bilsky score 0-1 versus 2-3 in: 1) preoperative presentation, 2) perioperative variables, and 3) long-term outcomes.

METHODS

A single-center, retrospective cohort study was undertaken of patients undergoing surgery for extradural, primary bone tumors of the spine between January 2010 and January 2021. The primary exposure variable was Bilsky score, dichotomized as 0-1 versus 2-3. Survival analysis was performed to assess local recurrence (LR) and overall survival (OS).

RESULTS

Of 38 patients undergoing resection of primary spinal tumors, 19 (50.0%) patients presented with Bilsky 0-1 and 19 (50.0%) Bilsky 2-3 grades. The most common diagnosis was chondrosarcoma (33.3%), followed by chordoma (16.7%). There were 15 (62.5%) malignant tumors. Preoperatively, there was no significant difference in demographics, Karnofsky Performance Scale (KPS) (P > 0.999), or motor deficit (P > 0.999). Perioperatively, no difference was found in operative time (P = 0.954), blood loss (P = 0.416), length of stay (P = 0.641), neurologic deficit (P > 0.999), or discharge disposition (P = 0.256). No difference was found in Enneking resection status (69.2% vs. 54.5%, P = 0.675). Long-term, no differences were found regarding reoperation (P = 0.327), neurologic deficit (P > 0.999), postoperative KPS (P = 0.605) and modified McCormick Scale (MMS) (P = 0.870). No difference was observed in KPS (P = 0.418) and MMS (P = 0.870) at last follow-up. However, patients with Bilsky 2-3 had shorter time to LR (1715.0 vs. 513.0 ± 633.4 days, log-rank; P = 0.002) and shorter OS (2025.0 ± 1165.3 vs. 794.0 ± 952.6 days, log-rank; P = 0.002).

CONCLUSIONS

Bilsky 2-3 lesions were associated with shorter time to LR and shorter OS. Patients harboring primary spinal tumors with higher grade Bilsky score appear to be at a higher risk for worse outcomes.

Percutaneous Vertebroplasty for Cervical Symptomatic Hemangiomas and Spinal Metastases: A Case Series and Literature Review

OBJECTIVE

Percutaneous vertebroplasty (PVP) is a commonly used technique for the treatment of spinal diseases, but it is rarely employed for cervical lesions. This study presents a case series and a literature review to evaluate the efficacy of cervical PVP.

METHODS

From August 2013 to January 2023, 14 patients underwent cervical PVP in the author's institution. The mean postoperative follow-up time was 20.3 ± 12.1 months (ranging from 5 to 41 months). The pain status and quality of life were assessed preoperatively, postoperatively, and during follow-up using the Visual Analog Scale and Neck Disability Index. Additionally, complications that occurred during the study period were documented.

RESULTS

The series of cases included 9 cases of hemangiomas and 5 cases of spinal metastases. The common symptom was axial pain in the neck. All patients were successfully treated with PVP. Visual analog scale scores decreased from 6.6 ± 0.8 preoperatively to 1.9 ± 0.8 at 24 hours postoperatively and to 2.4 ± 1.2 at the last follow-up (P < 0.01). Neck Disability Index decreased from 22.3% ± 8.9% preoperatively to 7.6% ± 8.1% at 24 hours postoperatively and to 6.0% ± 7.2% at 12-month follow-up (P < 0.01). After the operation, a case of dysphagia occurred, but no major complications were observed during the follow-up period.

CONCLUSIONS

Cervical PVP via the anterolateral approach is a safe option for the treatment of cervical symptomatic hemangiomas and spinal metastases with limited invasiveness. It is effective in relieving pain and improving quality of life.

The role of minimally invasive surgery within a multidisciplinary approach for patients with metastatic spine disease over a decade: A systematic review

BACKGROUND

Metastatic spine disease (MSD) occurs commonly in cancer patients causing pain, spinal instability, devastating neurological compromise, and decreased quality of life. Oncological patients are often medically complex and frail, precluding them form invasive procedures. To address this issue, minimally invasive spinal surgery (MISS) techniques are desirable. The aim of this study is to review published peer-reviewed literature and ongoing clinical trials to provide current state of the art.

METHODS

A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, assessing MISS in MSD patients for the period 2013-2023. Innovations under development were assessed by querying and reviewing data from currently enrolling U.S. registered clinical trials.

RESULTS

From 3,696 articles, 50 studies on 3,196 patients focused on spinal oncology MISS. The most commonly reported techniques were vertebral augmentation (VA), percutaneous spinal instrumentation, and radiofrequency ablation (RFA). Surgical instrumentation/stabilization techniques were reported in 10/50 articles for a total of 410 patients. The majority of studies focused on pain as a primary outcome measure, with 28/50 studies reporting a significant improvement in pain following intervention. In the United States, 13 therapeutic trials are currently recruiting MSD patients. Their main focus includes radiosurgery, VA and/or RFA, and laser interstitial thermal therapy.

CONCLUSIONS

Due to their medical complexity and increased fragility, MSD patients may benefit from minimally invasive approaches. These strategies are effective at mitigating pain and preventing neurological deterioration, while providing other advantages including ease to start/resume systemic/radiotherapy treatment(s).

Rapid Recuperation After Surgical Intervention and Rehabilitation in a Patient With Spinal Hemangioma: A Case Report

This case report describes the remarkable recovery journey of a 42-year-old male who suffered from neurological symptoms over three months, including tingling in both lower extremities. It was determined that a spinal hemangioma, a normally non-cancerous medical ailment, was the cause of these symptoms, which were also accompanied by difficulty walking and problems with bowel and bladder incontinence. A laminectomy and spinal cord decompression surgery were the two most significant medical procedures the patient underwent as part of his treatment, followed by a carefully structured rehabilitation program, as part of a holistic approach. Astoundingly, the patient's physical condition showed considerable improvements in several areas just one week after surgery. The reduction of pain, increased range of motion (ROM), and increased muscular strength were the aspects where these changes were most noticeable. This quick recovery reflects the benefit of combining surgical and rehabilitation techniques in these patients. The patient was prescribed a home exercise program (HEP) at the time of his discharge from the hospital so that he could continue his recovery independently in the comfort of his own home. This HEP was created to ensure that the patient could keep up and continue to make progress. This case report sheds light on the benefits of adopting a comprehensive strategy while treating spinal hemangiomas. The combined efforts of the surgical and rehabilitation therapy teams greatly improved the patient's prognosis. This aspect of synergy helped develop a whole treatment strategy that included both surgical tumor removal and crucial postoperative rehab for optimum healing and function.

Nadir Hemoglobin Concentration After Spinal Tumor Surgery: Association With Risk of Composite Adverse Events

STUDY DESIGN

Retrospective case-control study.

OBJECTIVE

To explore the association of early postoperative nadir hemoglobin with risk of a composite outcome of anemia-related and other adverse events.

METHODS

We retrospectively analyzed data from spinal tumor patients who received intraoperative blood transfusion between September 1, 2013 and December 31, 2020. Uni- and multivariate logistic regression was used to explore relationships of clinicodemographic and surgical factors with risk of composite in-hospital adverse events, including death. Subgroup analysis explored the relationship between early postoperative nadir hemoglobin and composite adverse events.

RESULTS

Among the 345 patients, 331 (95.9%) experienced early postoperative anemia and 69 (20%) experienced postoperative composite adverse events. Multivariate logistic regression analysis showed that postoperative nadir Hb (OR = .818, 95% CI: .672-.995, P = .044), ASA ≥3 (OR = 2.007, 95% CI: 1.086-3.707, P = .026), intraoperative RBC infusion volume (OR = 1.133, 95% CI: 1.009-1.272, P = .035), abnormal hypertension (OR = 2.199, 95% CI: 1.085-4.457, P = .029) were correlated with composite adverse events. The lumbar spinal tumor was associated with composite adverse events with a decreased odds compared to thoracic spinal tumors (OR = .444, 95% CI: .226-.876, P = .019). Compared to patients with postoperative nadir hemoglobin ≥11.0 g/dL, those with nadir <9.0 g/dL were at significantly higher risk of postoperative composite adverse events (OR = 2.709, 95% CI: 1.087-6.754, P = .032).

CONCLUSION

Nadir hemoglobin <9.0 g/dL after spinal tumor surgery is associated with greater risk of postoperative composite adverse events in patients who receive intraoperative blood transfusion.

Prognostic factors of sarcomas occurring in bone and joint: A SEER based study

To clarify the epidemiology, treatment, and prognosis of sarcomas occurring in the bones and joints. The surveillance, epidemiology, and end results (SEER) 18 registries, comprising sarcoma diagnoses made between 2008 and 2014, were queried for sarcomas arising in bones or joints. Kaplan-Meier analysis, multivariate logistic regression analysis, Cox proportional hazards model, and nomograms were used to identify prognostic factors. 2794 patients aged from 1 to 99 (55.8% male) with microscopically confirmed diagnosed as sarcomas (including osteosarcoma, chondrosarcoma, Ewing sarcoma, and soft tissue sarcomas) which primary site limited to bone and joint were identified. Eight independent factors, including age, race, sex, tumor site, histology, pathology grade, tumor size, and total number of malignant tumors (TNOMT), were associated with tumor metastasis. Nine independent prognostic factors, including age (>=60 year, hazard ratio [HR] = 4.145, 95% confidence interval [CI], P < .001), sex (female, HR = 0.814, 95%CI, P = .007), tumor site (spine, HR = 2.527, 95%CI, P < .001), histology, pathology grade (undifferentiated, HR = 5.816, 95%CI, P < .001), tumor size (>=20 cm, HR = 3.043, 95%CI, P < .001), tumor extent (distant, HR = 4.145, 95%CI, P < .001), surgery (no performed, HR = 2.436, 95%CI, P < .001), and TNOMT (1, HR = 0.679, 95%CI, P < .001, were identified and incorporated to construct a nomogram for 2- and 5-year overall survival (OS). The calibration curve for the probability of survival showed good agreement between prediction by the nomogram and actual observation. The C-index of the nomogram for survival prediction was 0.814. Patients who received chemotherapy had a significantly decreased risk of death only for Ewing sarcoma, poorly differentiated tumors, undifferentiated tumors, and distant tumor invasion (P < .05). However, radiotherapy did not show significant differences in OS. This study presents population-based estimates of prognosis for patients with bone sarcomas and demonstrates the impact of age, race, sex, tumor site, histology, pathology grade, tumor size, tumor extent, surgery, radiotherapy, chemotherapy, and the TNOMT on OS. Moreover, the nomogram resulted in a more accurate prognostic prediction. However, in our study, radiotherapy showed no survival benefit, perhaps because detailed data on treatment factors were unavailable and which may have influenced the results.

Posterior-only approach in patients with poor general condition and spinal metastatic vertebral fracture

PURPOSE

The surgical treatment of spinal metastases is mostly palliative in nature and focuses on improving the quality of life of patients. The posterior transpedicular surgical approach provides circumferential 360° decompression, allows reconstruction and stabilisation to be achieved in a single session and can be performed using an open, mini-open or minimally invasive approach. We present and discuss the surgical techniques and outcomes for patients with single-level metastatic spinal disease and in poor general condition who underwent surgery via the posterior-only transpedicular corpectomy approach and reconstruction with expandable corpectomy cages.

METHODS

Patients with a single level thoracolumbar metastatic disease (T3-L5) and a Karnofsky score of ≤70, who underwent a complete posterior transpedicular corpectomy with expandable cage reconstruction of the anterior spinal column were retrospectively reviewed. Patients' demographics, SINS, modified Tokuhashi scores as well as preoperative and postoperative ASIA scale, Karnofsky scores, VAS scores and vertebral height/Cobb angle values were analysed.

RESULTS

A total of 44 patients (24 M/20 F) (mean age 53.25±21.26 years) met the inclusion criteria. The modified Tokuhashi scores were as follows: score 0-8, 5 (11.4%) patients; score 9-11, 14 (31.8%) patients; and score 12-15, 25 (56.8%) patients. There were significant improvements in the postoperative VAS scores (mean 7.7-2.9), Karnofsky scores (mean 63.3-79.6) as well as the Cobb angles (18.6-12.8°) and vertebral height. Thirtyfive patients showed improved neurological function by at least one ASIA grade, whereas 9 showed no improvement during the postoperative period.

CONCLUSIONS

This technique, which has a low complication rate and a short recovery time, can help achieve satisfactory results even in patients with poor metabolic profiles and Karnofsky scores in the preoperative period. Further clinical studies with large patient groups are warranted to confirm the results of this study.

Primary Benign Neoplasms of the Spine

Benign tumours comprise the majority of primary vertebral tumours, and these are often found incidentally on imaging. Nonetheless, accurate diagnosis of these benign lesions is crucial, in order to avoid misdiagnosis as more ominous malignant lesions or infection. Furthermore, some of these tumours, despite their benign nature, can have localised effects on the spine including neural compromise, or can be locally aggressive, thus necessitating active management. Haemangiomas and osteomas (enostosis) are the commonest benign tumours encountered. Others include osteoid osteoma, osteoblastoma, fibrous dysplasia, osteochondroma, chondroblastoma, haemangioma, simple bone cysts, aneurysmal bone cysts, giant cell tumours, eosinophilic granuloma and notochordal rests. The majority of lesions are asymptomatic; however, locally aggressive lesions (such as aneurysmal bone cysts or giant cell tumours) can present with nonspecific symptoms, such as back pain, neurological deficits and spinal instability, which may be indistinguishable from more commonly encountered mechanical back pain or malignant lesions including metastases. Hence, imaging, including radiography, computed tomography (CT) and magnetic resonance imaging (MRI), plays a critical role in diagnosis. Generally, most incidental or asymptomatic regions are conservatively managed or may not require any follow-up, while symptomatic or locally aggressive lesions warrant active interventions, which include surgical resection or percutaneous treatment techniques. Due to advances in interventional radiology techniques in recent years, percutaneous minimally invasive techniques such as radiofrequency ablation, sclerotherapy and cryoablation have played an increasing role in the management of these tumours with favourable outcomes. The different types of primary benign vertebral tumours will be discussed in this article with an emphasis on pertinent imaging features.

Evaluation and Treatment of the Child with Acute Back Pain

Back pain is common, in up to 30% of children, increasing with age. Eighty percent is benign, mechanical type, improving within 2 weeks of conservative care. Required for those not improving is in-depth evaluation, including MRI, laboratory, and peer consultations. Spondylolysis and spondylolisthesis comprise almost 10% of pediatric back pain, often caused by lumbar hyperextension activities and treated conservatively in most cases. Osteoid osteomas and osteoblastomas constitute the most common benign spinal tumors in childhood. Aggressive and malignant tumors of the spine are rare but when present require tertiary care referral and a comprehensive oncology team for optimal life-sustaining outcomes.

Vertebral Primary Bone Lesions: Review of Management Options

The assessment and treatment of vertebral primary bone lesions continue to pose a unique yet significant challenge. Indeed, there exists little in the literature in the way of compiling and overviewing the various types of vertebral lesions, which can often have complicated intervention strategies. Given the severe consequences of mismanaged vertebral bone tumors-including the extreme loss of motor function-it is clear that such an overview of spinal lesion care is needed. Thus, in the following paper, we aim to address the assessment of various vertebral primary bone lesions, outlining the relevant nonsurgical and surgical interventional methods. We describe examples of primary benign and malignant tumors, comparing and contrasting their differences. We also highlight emerging treatments and approaches for these tumors, like cryoablation and stereotactic body radiation therapy. Ultimately, we aim to emphasize the need for further guidelines in regard to correlating lesion type with proper therapy, underscoring the innate diversity of vertebral primary bone lesions in the literature.

Development and validation of nomograms predicting overall and cancer-specific survival for non-metastatic primary malignant bone tumor of spine patients

At present, no study has established a survival prediction model for non-metastatic primary malignant bone tumors of the spine (PMBS) patients. The clinical features and prognostic limitations of PMBS patients still require further exploration. Data on patients with non-metastatic PBMS from 2004 to 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate regression analysis using Cox, Best-subset and Lasso regression methods was performed to identify the best combination of independent predictors. Then two nomograms were structured based on these factors for overall survival (OS) and cancer-specific survival (CSS). The accuracy and applicability of the nomograms were assessed by area under the curve (AUC) values, calibration curves and decision curve analysis (DCA). Results: The C-index indicated that the nomograms of OS (C-index 0.753) and CSS (C-index 0.812) had good discriminative power. The calibration curve displays a great match between the model's predictions and actual observations. DCA curves show our models for OS (range: 0.09-0.741) and CSS (range: 0.075-0.580) have clinical value within a specific threshold probability range compared with the two extreme cases. Two nomograms and web-based survival calculators based on established clinical characteristics was developed for OS and CSS. These can provide a reference for clinicians to formulate treatment plans for patients.

A current review of spinal meningiomas: epidemiology, clinical presentation and management

PURPOSE

To provide an up-to-date review of the epidemiology, histopathology, molecular biology, and etiology of spinal meningiomas, as well as discuss the clinical presentation, clinical evaluation, and most recent treatment recommendations for these lesions.

METHODS

PubMed and Google Scholar search was performed for studies related to meningiomas of the spine. The terms "meningioma," "spinal meningioma," "spine meningioma," "meningioma of the spine," "benign spinal tumors," and "benign spine tumors," were used to identify relevant studies. All studies, including primary data papers, meta-analyses, systematic reviews, general reviews, case reports, and clinical trials were considered for review.

RESULTS

Eighty-four studies were identified in the review. There were 22 studies discussing adverse postoperative outcomes, 21 studies discussing tumor genetics, 19 studies discussing epidemiology and current literature, 9 studies discussing radiation modalities and impact on subsequent tumor development, 5 studies on characteristic imaging findings, 5 studies discussing hormone use/receptor status on tumor development, 2 discussing operative techniques and 1 discussing tumor identification.

CONCLUSION

Investigations into spinal meningiomas generally lag behind that of intracranial meningiomas. Recent advancements in the molecular profiling of spinal meningiomas has expanded our understanding of these tumors, increasing our appreciation for their heterogeneity. Continued investigation into the defining characteristics of different spinal meningiomas will aid in treatment planning and prognostication.

DEVELOPMENT OF A MATHEMATICAL MODEL OF SELECTING THE EXTENT OF A SURGICAL INTERVENTION IN SPINAL TUMOR

OBJECTIVE

The aim: To develop a mathematical model of selecting the extent of surgical intervention in the spinal tumors.

PATIENTS AND METHODS

Materials and methods: The retrospective study included 237 patients with spinal tumors who underwent the following surgeries: vertebroplasty (V); vertebroplasty and spinal fixation (F+V); posterior spinal decompression and spinal fixation (F+F); vertebrectomy and replacement of vertebra by a cage with posterior spinal fixation (F+F+K). The mathematical model is based on the modified Spine Instability Neoplastic Score (SINS). The patients were divided into two clusters. Cluster analysis was used to build a diagnostic decision tree model.

RESULTS

Results: The difference between two clusters is determined by the extent of surgical intervention, the grade of the vertebral lesion, epidural compression, and local kyphosis, and neurological signs as well. The cluster 1 included 115 patients with higher values of SINS compared to the cluster 2. All cases of vertebroplasty belonged to the cluster 2. In the cluster 1 cases of surgery of large extent: F+F; F+V; F+F+K. Analysis of the decision tree model for cluster 1 showed that a type of surgery was determined for 97 patients from 115 that relates to 84.3% of overall accuracy. The decision tree model have a high predictive accuracy for the surgery F+V and better indicators of coverage and predictive accuracy for the surgery F+F+K.

CONCLUSION

Conclusions: Our study developed a decision tree model to optimize spinal neoplasm surgery, achieving 84.3% accuracy based on significant prognosis criteria. The model considers surgical type, neurological signs, vertebra lesion grade, and stage of epidural compression, potentially improving clinical outcomes.

Prognostic factors and treatment outcomes of spinal osteosarcoma: Surveillance, epidemiology, and end results database analysis

Objective

Spinal osteosarcoma is a rare osseous neoplasm. The aim of this study is to make a comprehensive analysis of the demographic features, clinicopathologic characteristics and factors affecting prognosis of spinal osteosarcoma using the Surveillance, Epidemiology and End Results (SEER) database.

Methods

SEER data were reviewed to identify patients diagnosed with spinal osteosarcoma between 1975 and 2016 and determine their overall survival (OS) and disease-specifc survival (DSS). Univariate and multivariate analyses were performed using the Cox-regression proportional hazards model and Kaplan-Meier method.

Results

A total of 668 patients (53.1% males) with spinal osteosarcoma were identified. The mean age at diagnosis was 45.2 years, including 67.5% patients younger than 60 years. The median OS of these patients was 15 months, and the 5-year OS was 16.8%. Multivariate analysis showed that age ≥60 year (HR=2.271, p = 0.008), high grade (HR=1.323, p = 0.008), regional stage (HR=1.658, p = 0.017), metastasis stage (HR=3.045, p < 0.001) and no-surgery treatment (HR=1.761, p < 0.001) were adversely associated with OS; gender (HR=0.657, p = 0.044), tumor grade (HR=1.616, p = 0.006), tumor stage (HR=3.329, p = 0.011; HR=7.983, p < 0.001) and radiotherapy (HR=0.606, p = 0.031) were independent prognostic factors affecting DSS.

Conclusion

Based on SEER data analysis, male, high tumor grade, regional stage, metastasis stage and radiotherapy are independent predictors of poor survival of patients with spinal osteosarcoma. The clinical treatment of spinal osteosarcoma still faces serious challenges. Future research should focus on the clinical impact and survival outcomes of the emerging targeted and immune therapies for the sake of improving the survival stalemate of spinal osteosarcoma.

Spinal cord motor disorders

Spinal cord diseases are frequently devastating due to the precipitous and often permanently debilitating nature of the deficits. Spastic or flaccid paraparesis accompanied by dermatomal and myotomal signatures complementary to the incurred deficits facilitates localization of the insult within the cord. However, laboratory studies often employing disease-specific serology, neuroradiology, neurophysiology, and cerebrospinal fluid analysis aid in the etiologic diagnosis. While many spinal cord diseases are reversible and treatable, especially when recognized early, more than ever, neuroscientists are being called to investigate endogenous mechanisms of neural plasticity. This chapter is a review of the embryology, neuroanatomy, clinical localization, evaluation, and management of adult and childhood spinal cord motor disorders.

A Simple-to-Use Nomogram for Predicting Postoperative Early Death Risk in Elderly Patients with Spinal Tumors: A Population-Based Study

Background

For elderly patients with primary spinal tumors, surgery is the best option for many elderly patients, in addition to palliative care. However, due to the unique physical function of elderly patients, the short-term prognosis is often unpredictable. It is therefore essential to develop a novel nomogram as a clinical aid to predict the risk of early death for elderly patients with primary spinal tumors who undergo surgery.

Materials and Methods

In this study, clinical data were obtained from 651 patients through the SEER database, and they were retrospectively analyzed. Logistic regression analyses were used for risk-factor screening. Predictive modeling was performed through the R language. The prediction models were calibrated as well as evaluated for accuracy in the validation cohort. The receiver operating characteristic (ROC) curve and the decision curve analysis (DCA) were used to evaluate the functionality of the nomogram.

Results

We identified four separate risk factors for constructing nomograms. The area under the receiver operating characteristic curve (training set 0.815, validation set 0.815) shows that the nomogram has good discrimination ability. The decision curve analysis demonstrates the clinical use of this nomogram. The calibration curve indicates that this nomogram has high accuracy. At the same time, we have also developed a web version of the online nomogram for clinical practitioners to apply.

Conclusions

We have successfully developed a nomogram that can accurately predict the risk of early death of elderly patients with primary spinal tumors undergoing surgery, which can provide a reference for clinicians.

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.

Nontraumatic Spinal Cord Injury: Epidemiology, Etiology and Management

The spinal cord is a conduit within the central nervous system (CNS) that provides ongoing communication between the brain and the rest of the body, conveying complex sensory and motor information necessary for safety, movement, reflexes, and optimization of autonomic function. After a traumatic spinal cord injury (SCI), supraspinal influences on the peripheral nervous system and autonomic nervous system (ANS) are disrupted, leading to spastic paralysis, sympathetic blunting, and parasympathetic dominance, resulting in cardiac dysrhythmias, systemic hypotension, bronchoconstriction, copious respiratory secretions, and uncontrolled bowel, bladder, and sexual dysfunction. This article outlines the pathophysiology of the less reported nontraumatic SCI (NTSCI), its classification, its influence on sensory/motor function, and introduces the probable comorbidities associated with SCI that will be discussed in more detail in the accompanying manuscripts of this special issue. Finally, management strategies for NTSCI will be provided.

Spinal brachytherapy

Brachytherapy remains an underrecognized and underutilized radiation therapy modality for the treatment of spinal tumors. This article summarizes the existing body of medical literature on the usage, indications, techniques, and outcomes of brachytherapy for the treatment of spine tumors. The disease pathology most commonly treated with brachytherapy is metastatic spine cancer, rather than primary bone tumors of the spine. Brachytherapy can be used alone, as percutaneous needle injections; however, it is more often used in conjunction with open surgery or cement vertebral body augmentation. Although the data are still relatively sparse, studies show consistent benefit from brachytherapy in terms of improvements in pain, function, local recurrence rate, and overall survival. Brachytherapy is also associated with a favorable complication profile.

A 68-Year-Old Woman with a Remote History of Breast Cancer Presenting with Low Back Pain to a Chiropractic Clinic in Hong Kong with Imaging Findings Consistent with a Vertebral Hemangioma and Vertebral Metastatic Lesions

BACKGROUND Patients commonly visit chiropractic clinics for treatment for low back pain, which is often due to injury or degenerative spinal conditions. Rarely, serious underlying pathology may be identified. This report describes a 68-year-old woman with a remote history of breast cancer presenting with low back pain to a chiropractic clinic in Hong Kong with imaging findings consistent with vertebral hemangioma and vertebral metastatic lesions. CASE REPORT A 68-year-old woman with a history of breast cancer status after chemotherapy and mastectomy 20 years prior presented to a chiropractor with an acute exacerbation of chronic low back pain with lower extremity paresthesia. She previously visited her general practitioner and underwent radiography, which supported diagnoses of degenerative lumbar spondylosis and hemangioma of the fifth lumbar vertebra. Given the patient's worsening status and previous cancer, the chiropractor ordered lumbar magnetic resonance imaging at the initial visit, consistent with multilevel spinal metastasis. The chiropractor referred the patient to an oncologist who performed positron emission tomography/computed tomography, which suggested breast cancer recurrence and metastasis. The greatest hypermetabolic activity was evident within the level of the suspected vertebral hemangioma, suggesting this finding which initially appeared innocuous on plain radiography contained underlying metastasis. CONCLUSIONS This case illustrates that when patients fail to respond to treatment for low back pain, clinical referral should be undertaken for investigations to identify possible serious underlying pathology.

A Rare Case of Epithelioid Hemangioma Presenting as an Isolated Sacral Mass

Epithelioid hemangioma (EH) is an uncommon benign vascular tumor of mesenchymal origin. It mainly presents as expanding nodules around the ear, the forehead, and long bones. Only a handful of cases have been found in cervical, thoracic, lumbar, and sacral vertebrae as lytic lesions with pain and neurological impairment. We present the case of a 36-year-old female with an incidental finding of a sacral mass along with inguinal lymphadenopathy on imaging. Initially, there were no symptoms. The mass gradually progressed and later showed an extraosseous extension with involvement of sacral neural foramina and nerve roots causing severe low back pain and weakness of the left lower extremity. Differential diagnoses initially included secondary metastases and chordoma. However, the biopsy of the mass revealed findings consistent with an EH. To our knowledge, this is the first case of EH presenting as an isolated mass in the sacrum and the third case of EH involving the sacrum in continuation with other vertebrae. EH should be in our differential diagnoses when there is a sacral mass.

An Atypical Presentation of Non-Hodgkin’s Lymphoma

Lymphomas result from the proliferation of malignant lymphocytes, which can affect lymph nodes, blood, and other organs. Primary involvement of the spine by haematological diseases is rare. Non-Hodgkin's lymphoma with an extranodal location most frequently involves the gastrointestinal tract and airways, affecting the bone, muscle, and nervous system.

We present a clinical case of an atypical form of non-Hodgkin's lymphoma. A 78-year-old woman was admitted to the hospital with complaints of pain in the lumbar region, hip, and left leg for the last month. Computed tomography of the lumbar spine revealed a mass of left paravertebral tissue with involvement from L3 to L5. Thoraco-abdominal CT-guided biopsy revealed diffuse large-cell non-Hodgkin B lymphoma. The remainder of the study did not show lymphatic involvement, so a diagnosis of primary extranodal large cell non-Hodgkin B lymphoma was made.

Staged Cement Injections for Massive Sacral Hemangioma

Vertebral hemangiomas are typically asymptomatic; however, they can also be a source of severe axial back pain. In this report, the authors describe the case of an unusually large sacral hemangioma that was effectively treated with staged cement augmentation. A 57-year-old man presented with chronic mid-sacral pain that was episodically severe. Magnetic resonance imaging revealed a massive lytic defect involving a majority of the body of S1 with features consistent with a hemangioma. It was theorized that the patient's pain could be attributed to the compromised structural integrity of the proximal sacrum with associated microfractures. Extensive conservative treatment failed to ameliorate the pain. A cement augmentation procedure was therefore recommended to stabilize the proximal sacrum. Due to concern about the potential for cement embolic complications, a staged bilateral approach was chosen. In the first procedure, 12 mL of bone cement was injected into the right proximal sacrum. The pain was partially improved by this injection. A 2-month interval was observed before the second cement injection in order to give time for pulmonary recovery from any potential microscopic emboli. In the second stage, 8 mL of bone cement was injected into the left proximal sacrum with excellent pain relief. There were no complications from either injection. At the 5-year follow-up, the patient reported no recurrence of mid-sacral pain. To the authors' knowledge, this is the first case reporting the effective treatment of a sacral hemangioma with staged cement injections. [Orthopedics. 20XX;XX(X):xx-xx.].

Hospital Frailty Risk Score and healthcare resource utilization after surgery for metastatic spinal column tumors

OBJECTIVE

The Hospital Frailty Risk Score (HFRS) was developed utilizing ICD-10 diagnostic codes to identify frailty and predict adverse outcomes in large national databases. While other studies have examined frailty in spine oncology, the HFRS has not been assessed in this patient population. The aim of this study was to examine the association of HFRS-defined frailty with complication rates, length of stay (LOS), total cost of hospital admission, and discharge disposition in patients undergoing spine surgery for metastatic spinal column tumors.

METHODS

A retrospective cohort study was performed using the years 2016 to 2019 of the National Inpatient Sample (NIS) database. All adult patients (≥ 18 years old) undergoing surgical intervention for metastatic spinal column tumors were identified using the ICD-10-CM diagnostic codes and Procedural Coding System. Patients were categorized into the following three cohorts based on their HFRS: low frailty (HFRS < 5), intermediate frailty (HFRS 5-15), and high frailty (HFRS > 15). Patient demographics, comorbidities, treatment modality, perioperative complications, LOS, discharge disposition, and total cost of hospital admission were assessed. A multivariate logistic regression analysis was used to identify independent predictors of prolonged LOS, nonroutine discharge, and increased cost.

RESULTS

Of the 11,480 patients identified, 7085 (61.7%) were found to have low frailty, 4160 (36.2%) had intermediate frailty, and 235 (2.0%) had high frailty according to HFRS criteria. On average, age increased along with progressively worsening frailty scores (p ≤ 0.001). The proportion of patients in each cohort who experienced ≥ 1 postoperative complication significantly increased along with increasing frailty (low frailty: 29.2%; intermediate frailty: 53.8%; high frailty: 76.6%; p < 0.001). In addition, the mean LOS (low frailty: 7.9 ± 5.0 days; intermediate frailty: 14.4 ± 13.4 days; high frailty: 24.1 ± 18.6 days; p < 0.001), rate of nonroutine discharge (low frailty: 40.4%; intermediate frailty: 60.6%; high frailty: 70.2%; p < 0.001), and mean total cost of hospital admission (low frailty: $48,603 ± $29,979; intermediate frailty: $65,271 ± $43,110; high frailty: $96,116 ± $60,815; p < 0.001) each increased along with progressing frailty. On multivariate regression analysis, intermediate and high frailty were each found to be significant predictors of both prolonged LOS (intermediate: OR