Spinal osteosarcoma

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.

Lung and bone metastases patterns in limb osteosarcoma: Surgical treatment of primary site improves overall survival

Osteosarcoma (OS) is one of the most prevalent malignant bone tumors. The proportion of patients with limb OS was relatively high. Lung metastasis (LM) and bone metastasis are the first and second most common metastatic types of OS, respectively. A total of 270 new cases of LM, 55 new cases of bone metastases (BM), and 36 new cases of lung and BM were diagnosed in the surveillance, epidemiology and end results database from 2010 to 2019. Univariate and multivariate logistic regression analyses were used to identify the risk factors for lung and/or BM, and Cox regression analyses were performed to identify the prognostic factors for lung and/or BM. Kaplan-Meier curves and log-rank tests were used to analyze the overall survival of limb OS patients with lung and/or BM. Female sex, telangiectatic OS type, central OS type, T3 stage, N1 stage, BM, surgical treatments, radiotherapy and chemotherapy were significantly correlated with LM. T3 stage, LM, liver metastases, and radiotherapy significantly correlated with BM. The small cell OS type, T2 stage, T3 stage, N1 stage, liver metastases, and radiotherapy were significantly correlated with lung and BM. Among limb OS patients with LM, the mean survival months of older age, black race, N1 stage, BM, brain metastases, no surgery, and no chemotherapy were lower than those of the control group. In limb OS patients with LM and BM, the mean survival months in the no surgery group was lower than in the surgery group. T stage and radiotherapy significantly influence the occurrence of limb OS with lung and/or BM. Surgery at the primary site has been shown to be effective in improving the survival rate of patients with lung and/or BM.

Malignant Brain and Spinal Tumors Originating from Bone or Cartilage

Malignant bone tumors affecting the brain and spine are a rare and exceedingly difficult-to-treat group of diseases. Most commonly consisting of chordoma and chondrosarcoma, these tumors also include giant-cell tumors and osteosarcomas. This chapter will cover the background, epidemiology, genetics, molecular biology, histopathology, radiographic features, clinical manifestations, therapeutic approaches, and clinical management of each entity.

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 giant cell-rich osteosarcoma-diagnostic dilemma and treatment strategy: A case report

BACKGROUND

Giant cell-rich osteosarcoma (GCRO) is a rare histological variant of osteosarcoma. Spinal GCROs are extremely rare, with challenging diagnosis and management. Herein, we present a case of spinal GCRO at T2, which was not diagnosed in initial biopsy but after T2 corpectomy. We detailed the clinical course, management strategy, and outcome after a 4-year follow-up.

CASE SUMMARY

A 17-year-old female patient presented with back pain followed by ascending paresthesia. Spinal computed tomography (CT) and magnetic resonance imaging (MRI) revealed a collapsed T2 vertebra with an enhancing osteolytic mass. CT-guided biopsy showed inconclusive morphology. Pathology from T2 corpectomy revealed GCRO. The patient subsequently received neoadjuvant chemotherapy followed by salvage operation of T2 costotransversectomy with grossly-total resection adjuvant chemoradiation. Upon treatment completion, she had complete GCRO remission. The 4-year follow-up spinal MRI showed no tumor recurrence.

CONCLUSION

Spinal GCRO poses unique challenges in obtaining sufficient tissue diagnosis and complete surgical removal. However, long-term local control of spinal GCRO is possible following complete resection and adjuvant chemoradiation

Primary extradural tumors of the spinal column: A comprehensive treatment guide for the spine surgeon based on the 5th Edition of the World Health Organization bone and soft-tissue tumor classification

BACKGROUND

In 2020, the World Health Organization (WHO) published the 5th version of the soft tissue and bone tumor classification. Based on this novel classification system, we reviewed the current knowledge on all tumor entities with spinal manifestations, their biologic behavior, and most importantly the appropriate treatment options as well as surgical approaches.

METHODS

All tumor entities were extracted from the WHO Soft-Tissue and Bone Tumor Classification (5th Edition). PubMed and Google Scholar were searched for the published cases of spinal tumor manifestations for each entity, and the following characteristics were extracted: Growth pattern, ability to metastasize, peak age, incidence, treatment, type of surgical resection indicated, recurrence rate, risk factors, 5-year survival rate, key molecular or genetic alterations, and possible associated tumor syndromes. Surgical treatment strategies as well as nonsurgical treatment recommendations are presented based on the biologic behavior of each lesion.

RESULTS

Out of 163 primary tumor entities of bone and soft tissue, 92 lesions have been reported along the spinal axis. Of these 92 entities, 54 have the potential to metastasize. The peak age ranges from conatal lesions to 72 years. For each tumor entity, we present recommended surgical treatment strategies based on the ability to locally destruct tissue, to grow, recur after resection, undergo malignant transformation as well as survival rates. In addition, potential systemic treatment recommendations for each tumor entity are outlined.

CONCLUSION

Based on the 5th Edition of the WHO bone and soft tumor classification, we identified 92 out of 163 tumor entities, which potentially can have spinal manifestations. Exact preoperative tissue diagnosis and interdisciplinary case discussions are crucial. Surgical resection is indicated in a significant subset of patients and has to be tailored to the specific biologic behavior of the targeted tumor entity based on the considerations outlined in detail in this article.

The role of percutaneous transarterial embolization in the management of spinal bone tumors: a literature review

PURPOSE

Spinal bone tumors include a heterogeneous broad of primary or metastatic lesions that may present as incidental findings or manifest with painful symptoms and pathological fractures. Optimal management of spine bone lesions is often difficult and treatment algorithms are usually solidly based on surgery. We aimed to evaluate the contribution of trans-arterial embolization in this field, with particular attention to the procedure efficacy, technical difficulties and complications.

METHODS

We present a literature review on the role of trans-arterial embolization in the management of spinal bone tumors, both primary and metastatic, evaluating its contribution as preoperative treatment, palliative procedure and standalone curative strategy.

RESULTS

Trans-arterial embolization provides an important contribution to reducing surgery hemorrhagic risks, offering a better visualization of the operating field, and possibly increasing tumor susceptibility to chemotherapy or radiation therapy. Nonetheless, it plays an important part in pain palliation, with the unquestionable advantage of being easily repeatable in case of necessity. Its curative role as a standalone therapy is still subject of debate, and at the present time, satisfactory results have been recorded only in the treatment of aneurysmal bone cysts.

CONCLUSION

Percutaneous trans-arterial embolization has established as a highly useful minimally invasive procedure in the management of spinal bone lesions, particularly as adjuvant preoperative therapy and palliative treatment.

Primary mobile vertebral column sarcomas: Prognostic factors vary by histologic subtypes

BACKGROUND

Primary sarcomas originating from the mobile spine portends a particularly sinister outcome. Rarity of the disease process has resulted in inconsistent data due to small sample size and heterogeneity in patient selection and analytics.

METHODS

Surveillance, Epidemiology and End Result (SEER) database from 1975 to 2017 was queried to report incidence and survival data in 712 patients in the United States. Kaplan-Meier and Cox Regression were used to determine the prognostic factors affecting survival.

RESULTS

Incidence of spinal sarcoma was 0.019 per 100,000 persons in 2017 and has not significantly changed since 2000 (p > 0.05). Disease-specific 5-year survival for the entire cohort was 57%. Osteosarcoma has the worst 5-year survival (39%) and chondrosarcoma has the best 5-year survival (69%). Independent predictors of survival for the entire cohort included age, grade, and stage. Stage was an independent predictor of survival for every histologic subtype. Additional predictors of survival for spinal osteosarcoma, Ewing sarcoma, and chondrosarcoma included age, size, and grade, respectively.

CONCLUSIONS

The current study is an analysis of a population-based registry reporting incidence survival data for patients with sarcoma of mobile vertebral column. Survival and prognostic factors vary by histologic subtypes. There is lack of improvement in survival over the last three decades.

Chordoma of the sacrum and mobile spine: a narrative review

Chordoma is a notochord-derived primary tumor of the skull base and vertebral column known to affect 0.08 to 0.5 per 100,000 persons worldwide. Patients commonly present with mechanical, midline pain with or without radicular features secondary to nerve root compression. Management of these lesions has classically revolved around oncologic resection, defined by en bloc resection of the lesion with negative margins as this was found to significantly improve both local control and overall survival. With advancement in radiation modalities, namely the increased availability of focused photon therapy and proton beam radiation, high-dose (>50 Gy) neoadjuvant or adjuvant radiotherapy is also becoming a standard of care. At present chemotherapy does not appear to have a role, but ongoing investigations into the ontogeny and molecular pathophysiology of chordoma promise to identify therapeutic targets that may further alter this paradigm. In this narrative review we describe the epidemiology, histopathology, diagnosis, and treatment of chordoma.

Indeterminate Cell Histiocytosis of the Spine: A Case Report

INTRODUCTION

Indeterminate cell histiocytosis is a rare neoplastic disease characterized by proliferation of dendritic cells that share morphologic and immunophenotypic features of Langerhans cells and non-Langerhans histiocytes. ICH lesions are typically restricted to the skin; however, there have been rare reports of extracutaneous and systemic involvement.

CASE PRESENTATION

We describe a case of a 13-year-old female presenting with complaints of worsening lower back pain for 1 year. CT and MRI of the lumbar spine demonstrated a well-defined bony, lytic, expansile lesion of the posterior and mid-endplate of the L4 vertebra with mass effect on the thecal sac. The patient underwent L3-L5 decompression and fusion with surgical excision of the vertebral body tumor. Microscopic examination of the lesion showed benign fibrohistiocytic proliferation with giant cells, and immunohistochemical staining revealed a phenotype consistent with indeterminate cell histiocytosis (S100+ CD1a+ langerin-).

DISCUSSION/CONCLUSION

ICH is an extraordinarily rare neoplastic disease of dendritic cells that has a poorly understood pathogenesis. This case expands the spectrum of potential ICH extracutaneous involvement to now include the spine, a location previously undocumented in the literature in the pediatric population.

An overview of the tumors affecting the spine-inside to out

Spine tumors may arise within or surrounding the spinal cord and/or vertebral column. Spinal tumors can be benign or malignant. Based on their epicenter, they may be classified as intradural-intramedullary, intradural-extramedullary, or extradural. Of these, extradural lesions are the most common, and are typically metastatic. Primary bone tumors of the spinal column comprise 5% of all primary skeletal tumors. The majority of primary spinal column tumors are benign, with malignant tumors comprising only 20%. Overall, spine metastases are the most common malignant spine tumor, and these usually arise from primaries such as lung, breast, and prostate cancers. The advent of improved systemic therapies leading to improved survival and the frequent use of imaging has positioned metastatic spine disease as the new epidemic in oncology. For spine tumors, establishing the correct diagnosis is heavily reliant on magnetic resonance imaging and histological confirmation. In this review, we will provide an overview of the epidemiology, radiological and histopathological features, and the natural history of key primary (benign and malignant) spinal cord and column tumors and metastatic spine tumors. Treatment principles for primary spinal cord or column tumors are aimed toward curative resection, whereas palliative resection forms the treatment principle for most metastatic tumors.

Economics of the Management of Craniospinal Chordoma and Chondrosarcoma and the feasibility of the bundled payment model

BACKGROUND

The Centers for Medicare and Medicaid Services (CMS) created a new reimbursement model "Bundled Payment for Care Improvement (BPCI)" which reimburses providers a predetermined payment in advance to cover all possible services rendered within a certain time window. Chordoma and Chondrosarcoma are locally aggressive malignant primary bony tumors. Treatment includes surgical resection and radiotherapy with substantial risk for recurrence which necessitates monitoring and further treatment. We assessed the feasibility of the BPCI model in these neurosurgical diseases.

METHODS

We selected patients with chordoma/chondrosarcoma from inpatient admission table using the International Classification of Disease, 9th (ICD-9), and 10th (ICD-10) revision codes. We collected the patients' demographics and insurance type at the index hospitalization. We recorded the following outcomes length of stay, total payment, discharge disposition, and complications for the index hospitalization. For post-discharge, we collected the 30 days and 3/6/12 months inpatient admission, outpatient service, and medication refills. Continuous variables were summarized by means with standard deviations, median with interquartile and full ranges (minimum-maximum); Continuous outcomes were compared by nonparametric Wilcoxson rank-sum test. All tests were 2-sided with a significance level of 0.05. Statistical data analysis was performed in SAS 9.4 (SAS Institute, Inc, Cary, NC).

RESULTS

The population size was 2041 patients which included 1412 patients with cranial (group1), 343 patients with a mobile spine (group 2), and 286 patients with sacrococcygeal (group 3) chordoma and chondrosarcoma. For index hospitalization, the median length of stay (days) was 4, 6, and 7 for groups 1, 2, and 3 respectively (P<.001). The mean payments were ($58,130), ($84,854), and ($82,440), for groups 1, 2, and 3 respectively (P=.02). The complication rates were 30%, 35%, and 43% for groups 1, 2, and 3 respectively (P<.001). Twelve months post-discharge, the hospital readmission rates were 44%, 53%, and 65% for groups 1, 2, and 3, respectively (P<.001). The median payments for this period were ($72,294), ($76,827), and ($101,474), for groups 1, 2, and 3, respectively (P <.001).

CONCLUSION

The management of craniospinal chordoma and chondrosarcoma is costly and may extend over a prolonged period. The success of BPCI requires a joint effort between insurers and hospitals. Also, it should consider patients' comorbidities, the complexity of the disease. Finally, the adoptionof quality improvement programs by hospitals can help with cost reduction.

Bone up on spinal osseous lesions: a case review series

Spinal osseous neoplasms are frequently encountered and can be challenging when present as solitary lesions. Familiarity with the range of benign and malignant spinal pathology can help the radiologist formulate a comprehensive differential diagnosis. This article focuses on the spectrum of extradural spinal tumors, accounting for the majority of primary spinal tumors, by comparing the epidemiology, pathophysiology, clinical presentation, and characteristic imaging appearance of these lesions. The discussion includes the commonly encountered benign lesions, such as vertebral venous vascular malformation and enostosis, as well as malignant lesions including metastases and lymphoma. The article also includes other less-encountered primary spinal tumors such as plasmacytoma, osteoid osteoma, osteoblastoma, giant cell tumor, eosinophilic granuloma, chordoma, chondrosarcoma, osteosarcoma, Ewing’s sarcoma, and angiosarcoma. Familiarity with the characteristic imaging features can help the radiologist reach an accurate diagnosis and obviate the need for unnecessary invasive procedures such as biopsy and surgery.

Long noncoding RNA BSN-AS2 induced by E2F1 promotes spinal osteosarcoma progression by targeting miR-654-3p/SYTL2 axis

Spinal osteosarcoma (OS) is a rare and aggressive malignancy. Long noncoding RNA (lncRNA) BSN-AS2 has been shown to be an oncogenic gene in several cancers. However, the role and function of BSN-AS2 in spinal OS were unfamiliar. Our study identified that BSN-AS2 expression was boosted in spinal OS tissues and cell lines. Transcription factor E2F1 induced the upregulation of BSN-AS2 expression in spinal OS cells. Afterwards, loss-of-function assays indicated that BSN-AS2 depletion reduced cell proliferation, migration and invasion as well as promoted cell apoptosis in spinal OS. Thereafter, RIP, RNA pull down and luciferase reporter assays manifested BSN-AS2 could sponge miR-654-3p in spinal OS. After that, the binding effect of between miR-654-3p and SYTL2 was proved. Finally, rescue experiments illustrated that miR-654-3p inhibition or SYTL2 overexpression could counteract the inhibitory effect caused by BSN-AS2 deficiency on spinal OS progression. In conclusion, the availability of miR-654-3p was antagonized by E2F1-induced BSN-AS2 for SYTL2-meidated spinal OS progression.

Laminopedicular Osteotomy for En-bloc Resection of Posterolateral Thoracic Osteoblastoma: Technical Note

BACKGROUND

Osteoblastomas are a type of primary osseous neoplasm that exhibit a proclivity for the spine, primarily the posterior elements. While generally considered benign, some variants of osteoblastoma exhibit aggressive growth with lytic osseous destruction and soft tissue invasion, with some recurring after initial treatment. Given their proximity to vital structures and potential for rapid growth, these tumors are often managed with aggressive surgery, with en-bloc resection preferred.

METHODS

Here we describe our osteotomy technique for resecting en bloc a posterolateral thoracic osteoblastoma causing rapidly progressive myelopathy in a 17-year-old male.

RESULTS

Successful treatment of osteoblastoma in a 17-year-old male demonstrates the efficacy of our laminopedicular osteotomy technique in treating 1 instance of a rapidly presenting spinal tumor.

CONCLUSIONS

This case bolsters the growing body of literature that favors the outcomes of a more conservative approach to en-bloc resection of spinal tumors.

MicroRNA-761 targets FGFR1 to suppress the malignancy of osteosarcoma by deactivating PI3K/Akt pathway

Purpose

MicroRNA-761 (miR-761) has been reported to be deregulated in many types of human cancers and play important roles in cancer genesis and progression. However, the biological roles of miR-761 in osteosarcoma (OS) and the underlying mechanisms remain largely unknown.

Methods

The expression of miR-761 in OS tissues and cell lines was analyzed using RT-qPCR. A series of gain-of-function tests were performed, and status of malignancy was evaluated on basis of proliferation, migration, invasion, and apoptosis using different assays to determine the regulatory roles of miR-761 in OS cells in vivo and in vitro. Notably, the mechanisms underlying the action of miR-761 in the pathogenesis of OS were investigated using bioinformatic analysis, luciferase reporter assay, RT-qPCR and Western blotting.

Results

The results showed that miR-761 expression was decreased in OS tissues and cell lines and is closely correlated with clinical stage and distant metastasis in OS patients. Patients with OS having low miR-761 expression showed worse prognosis compared to OS patients with high miR-761 expression. Restoring the miR-761 expression level decreased OS cell proliferation, migration, and invasion in vitro; promoted cell apoptosis in vitro; and impaired tumor growth in vivo. In addition, fibroblast growth factor receptor 1 (FGFR1) was found as a direct target gene of miR-761 in OS cells. Furthermore, silencing FGFR1 expression stimulated the tumor-suppressing roles of miR-761 upregulation in OS cells, whereas the activity of miR-761 overexpression in OS cells was abolished by the restoration of FGFR1 expression. Moreover, restoration of miR-761 expression deactivated the PI3K/Akt pathway in vitro and in vivo.

Conclusion

These results suggest that miR-761 plays anti-cancer roles in OS by directly targeting FGFR1 and deactivating the PI3K/Akt pathway. The newly identified miR-761/FGFR1/PI3K/Akt pathway partially illustrates the mechanism of OS pathogenesis and presents a novel candidate therapeutic target for antitumor therapy.

Clinical effectiveness of Enneking appropriate versus Enneking inappropriate procedure in patients with primary osteosarcoma of the spine: a systematic review with meta-analysis

PURPOSE

Primary osteosarcoma of the spine is a rare osseous tumour. En bloc resection, in contrast to intralesional resection, is the only procedure able to provide Enneking appropriate (EA) margins, which has improved local control and survival of patients with primary osteosarcoma of the spine. The objective of this study is to compare the risk of local recurrence, metastases development and survival in patients with primary osteosarcoma of the spine submitted to Enneking appropriate (EA) and Enneking inappropriate (EI) procedures.

METHODS

A systematic search was performed on EBSCO, PubMed and Web of Science, between 1966 and 2018, to identify studies evaluating patients submitted to resection of primary osteosarcoma of the spine. Two reviewers independently assessed all reports. The outcomes were local recurrence, metastases development and survival at 12, 24 and 60 months.

RESULTS

Five studies (108 patients) were included for systematic review. These studies support the conclusion that EA procedure has a lower local recurrence rate (RR 0.33, 95% CI 0.17-0.66), a lower metastases development rate (RR 0.39, 95% CI 0.17-0.89) and a higher survival rate at 24 months (RR 1.78, 95% CI 1.24-2.55) and 60 months (RR 1.97, 95% CI 1.14-3.42) of follow-up; however, at 12 months, there is a non-significant difference.

CONCLUSIONS

EA procedure increases the ratio of remission and survival after 24 months of follow-up. Multidisciplinary oncologic groups should weigh the morbidity of an en bloc resection, knowing that in the first year the probability of survival is the same for EA and EI procedures. These slides can be retrieved under Electronic Supplementary Material.

Diagnostic challenges and surgical management of co-existent osteoblastoma and aneurysmal bone cyst of the lumbar spine in a child: case report

Background

Osteoblastomas (OTB) with co-existent aneurysmal bone cysts (ABC) of the spine are extremely rare and more so in the lumbar spine. To the authors' knowledge, only one case of lumbar spine involvement has been reported in a paediatric patient.

Objectives

To highlight diagnostic challenges and surgical management of co-existent lumbar OTB-ACB in a child.

Methods

We present a 14-year old female with low back pain and progressive swelling of 2 months. She was evaluated by neuroimaging studies and histopathological assessment of resected tissue.

Results

X-ray showed a lytic lesion in L3 with loss of the left pedicle. Magnetic resonance imaging (MRI) revealed a fluid-filled, heterogeneously enhanced, lobulated lesion posterior to the vertebral bodies of L3, L4 and L5, which infiltrated the quadratus lumborum muscles bilaterally, and histologically diagnosed as ABC. The L3 pedicle also revealed an expanded, heterogeneously enhanced mass lesion which appeared to be different and showed no fluid-filled levels, histologically diagnosed as OTB. Surgical intervention involved tumour excision with partial spondylectomy of L3 vertebra, posterior instrumented stabilization and fusion.

Conclusion

The case highlights the diagnostic challenges of co-existent OTB-ABC and the significant role of surgical management via spinal reconstruction, stabilization and fusion after gross total tumour excision.

Novel therapeutic strategies for spinal osteosarcomas

At the dawn of the third millennium, cancer has become the bane of twenty-first century man, and remains a predominant public health burden, affecting welfare and life expectancy globally. Spinal osteogenic sarcoma, a primary spinal malignant tumor, is a rare and challenging neoplastic disease to treat. After the conventional therapeutic modalities of chemotherapy, radiation and surgery have been exhausted, there is currently no available alternative therapy in managing cases of spinal osteosarcoma. The defining signatures of tumor survival are characterised by cancer cell ability to stonewall immunogenic attrition and apoptosis by various means. Some of these biomarkers, namely immune-checkpoints, have recently been exploited as druggable targets in osteosarcoma and many other different cancers. These promising strides made by the use of reinvigorated immunotherapeutic approaches may lead to significant reduction in spinal osteosarcoma disease burden and corresponding reciprocity in increase of survival rates. In this review, we provide the background to spinal osteosarcoma, and proceed to elaborate on contribution of the complex ecology within tumor microenvironment giving arise to cancerous immune escape, which is currently receiving considerable attention. We follow this section on the tumor microenvironment by a brief history of cancer immunity. Also, we draw on the current knowledge of treatment gained from incidences of osteosarcoma at other locations of the skeleton (long bones of the extremities in close proximity to the metaphyseal growth plates) to make a case for application of immunity-based tools, such as immune-checkpoint inhibitors and vaccines, and draw attention to adverse upshots of immune-checkpoint blockers as well. Finally, we describe the novel biotechnique of CRISPR/Cas9 that will assist in treatment approaches for personalized medication.

MicroRNA-493-5p inhibits proliferation and metastasis of osteosarcoma cells by targeting Kruppel-like factor 5

Osteosarcoma, including spinal osteosarcoma, has properties of high degree of malignancy, high rate of recurrence, and high incidence of metastasis. microRNAs can exert oncogenic or tumor suppressive roles in cancer cells. This study explored the effects of microRNA-493-5p (miR-493-5p) on osteosarcoma cell viability, migration, invasion, and apoptosis, as well as the underlying possible mechanism. First, the expression of miR-493-5p in osteosarcoma tissues and cells was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Then, the effects of miR-493-5p overexpression (or suppression) on osteosarcoma cell viability, migration, invasion, and apoptosis, as well as Kruppel-like factor 5 (KLF5) expression, were assessed using the Cell Counting Kit-8 assay, two-chamber transwell assay, Annexin V-FITC/PI apoptosis detection kit, qRT-PCR, and western blotting, respectively. Finally, the roles of KLF5 in miR-493-5p suppression-induced U20S cell viability, migration, and invasion enhancement, as well as the PI3K/AKT pathway activation, were evaluated. We found that miR-493-5p had lower expression in tumor tissues of spinal osteosarcoma and osteosarcoma cells. Overexpression of miR-493-5p inhibited osteosarcoma U20S cell viability, migration, and invasion, but induced cell apoptosis. On the contrary, suppression of miR-493-5p-promoted U20S cell viability, migration, and invasion. KLF5 was a direct target gene of miR-493-5p, which participated in the effects of miR-493-5p on U20S cell viability, migration, invasion, and apoptosis. Furthermore, suppression of the miR-493-5p activated PI3K/AKT pathway in U20S cells by upregulating KLF5. In conclusion, we revealed that miR-493-5p exerted tumor suppressive roles in spinal osteosarcoma and osteosarcoma cells. Overexpression of miR-493-5p inhibited proliferation and metastasis of osteosarcoma cells by downregulating KLF5 and inactivating the PI3K/AKT signaling pathway.

Bone transport using the Ilizarov method for osteosarcoma patients with tumor resection and neoadjuvant chemotherapy

Background

Studies on the applications of bone transport using the Ilizarov method for osteosarcoma (OS) patients with surgical resection and neoadjuvant chemotherapy are rare.

Methods

A retrospective analysis was conducted in 10 patients with limb OS receiving limb-salvage treatment by Ilizarov method from 2007 to 2012 in our hospital. The general information, treatment outcomes and follow-up data of the patients were collected.

Results

The mean length of the transported fragment and the mean transport distance of the affected limb were both 14 cm. The mean time in the external fixator was 34.2 ± 11.2 months (16-47 months) and the mean external fixation index (EFI) was 75 days/cm. The mean follow-up time was 68.6 ± 26.6 months (37-103 months). Seven patients underwent additional operations to treat the postoperative complications, and the mean number of operation was 1.7 times. Only one patient underwent amputation due to tumor relapse and all patients survived without tumor. The limb-salvage rate was 90%. At the time of external fixator removal, the ASAMI-bone score was good in 66.7% of patients and the ASAMI-function score was fair in 66.7% of cases. The mean MSTS score was 18.6 ± 3.2 (n = 9). At 10 months after fixator removal, both the ASAMI-bone score and ASAMI-function score were both excellent in 80% and good in 20% cases, and the mean MSTS score was further improved to 27.2 ± 1.11 (n = 5).

Conclusion

Bone transport using the Ilizarov method can achieve good therapeutic effectiveness in the limb-salvage treatment for OS patients with neoadjuvant chemotherapy as long as the complications can be timely recognized and well managed.

MicroRNA-194-3p inhibits the metastatic biological behaviors of spinal osteosarcoma cells by the repression of matrix metallopeptidase 9

Osteosarcoma is the most common primary malignant bone tumor, but only 3%-5% of cases occur in the spine. Spinal osteosarcoma presents a significant challenge, and most patients die in spite of aggressive surgery. MicroRNAs (miRNAs) are small noncoding RNAs that have a pivotal role in the post-transcriptional regulation of gene expression. The aim of this study was to investigate the role of miR-194-3p and to identify its potential mechanism in spinal osteosarcoma. Here, spinal osteosarcoma tissues showed down-regulated expression of miR-194-3p compared to adjacent non-tumorous tissues. The level of miR-194-3p was negatively correlated with metastasis in patients with spinal osteosarcoma. MiR-194-3p over-expression in spinal osteosarcoma cells significantly inhibited cell migration and invasion in vitro. Furthermore, mechanistic analyses showed that MMP-9 (matrix metallopeptidase 9) is a direct target of miR-194-3p, and the ectopic expression of miR-194-3p inhibits MMP-9 expression by directly binding to the 3'-untranslated region (3'-UTR) of the MMP-9 gene. In summary, our results demonstrate that miR-194-3p suppresses migration and invasion of spinal osteosarcoma cells by targeting MMP-9, indicating miR-194-3p may serve as a promising novel target for spinal osteosarcoma therapy.

Imaging of Malignant Primitive Tumors of the Spine

Primary malignant tumors of the spine are rare and mainly include chordoma, chondrosarcoma, Ewing sarcoma or primitive neuroectodermal tumor, and osteosarcoma. The final diagnosis is based on the combination of patient age, topographic and histologic features of the tumor, and lesion pattern on computed tomography (CT) and magnetic resonance (MR) imaging. Imaging evaluation includes radiography, CT, bone scintigraphy, and MR imaging. CT is more useful than radiography for evaluating location of the lesion and analyzing bone destruction and matrix, whereas MR has unmatched ability to assess soft tissue extension. This pictorial review provides an overview of the most prevalent primitive malignant tumors of spine.

Magnetic kyphoplasty: A novel drug delivery system for the spinal column

Vertebral compression fractures (VCFs) caused by metastatic malignancies or osteoporosis are devastating injuries with debilitating outcomes for patients. Minimally invasive kyphoplasty is a common procedure used for symptomatic amelioration. However, it fails in treating the underlying etiologies of VCFs. Use of systemic therapy is limited due to low perfusion to the spinal column and systemic toxicity. Localized delivery of drugs to the vertebral column can provide a promising alternative approach. A porcine kyphoplasty model was developed to study the magnetically guided drug delivery of systemically injected magnetic nanoparticles (MNPs). Jamshidi cannulated pedicle needles were placed into the thoracic vertebra and, following inflatable bone tamp expansion, magnetic bone cement was injected to the vertebral body. Histological analysis was performed after intravenous injection of MNPs. Qualitative analysis of harvested tissues revealed successful placement of magnetic cement into the vertebral body. Further quantitative analysis of histological sections of several vertebral bodies demonstrated enhanced accumulation of MNPs to regions that had magnetic cement injected during kyphoplasty compared to those that did not. By modifying the kyphoplasty bone cement to include magnets, thereby providing a guidance stimulus and a localizer, we were successfully able to guide intravenously injected magnetic nanoparticles to the thoracic vertebra. These results demonstrate an in-vivo proof of concept of a novel drug delivery strategy that has the potential to treat the underlying causes of VCFs, in addition to providing symptomatic support.

Lumbar spinal canal osteosarcoma: A case report

RATIONALE

Osteosarcoma is a rare neoplasm in the lumbar spine. Although osteosarcoma can arise in any portion of the skeleton, it very rarely arises in the spinal canal, which accounts for <0.1% of all cases of adult sarcomas. Here, we describe a case of osteosarcoma arising in the L4-5 spinal canal.

PATIENT CONCERNS

The present report describes the case of a 55-year-old female patient with osteosarcoma of the L4-5 spinal canal.

DIAGNOSES

The patient was initially diagnosed with lumbar spinal stenosis and underwent lumbar fusion at a local hospital. At the 4-month follow-up, the patient reported a marked increase in numbness and pain in the lumbar region and lower limbs. Based on magnetic resonance imaging, we diagnosed a postoperative infectious lesion of the lumbar spine.

INTERVENTIONS

The patient underwent surgery for complete removal of the mass lesion. The mass measured 3 × 2.5 × 0.7 cm in size and was located in the L4-5 spinal canal.

OUTCOMES

Based on histological and immunohistochemical findings, the diagnosis of osteosarcoma was confirmed by an expert pathology consultant. The patient then received chemotherapy. Postoperative follow-up at 6 months revealed no evidence of recurrent disease or residual side effects from therapy.

LESSONS

Osteosarcoma in the L4-5 spinal canal is extremely rare and very difficult to distinguish histologically from benign nervous and fibrous tissue. This is a very valuable case, which highlights the need for orthopedic surgeons to consider this when diagnosing patients with spinal tumors.

In vivo pharmacological evaluation and efficacy study of methotrexate-encapsulated polymer-coated layered double hydroxide nanoparticles for possible application in the treatment of osteosarcoma

Considering the existing drawbacks of methotrexate (MTX) with respect to its solubility and toxicity, we incorporated it in a nanoceramic matrix, Mg-Al-layered double hydroxide (LDH) to form LDH-MTX nanoparticles, and the same was in turn encapsulated in a nontoxic and biodegradable polymer, poly (D,L-lactide-co-glycolide) (PLGA), to arrest the initial burst release and dose-dumping-related toxicity, already reported by our group. Our present study was designed to evaluate the pharmacokinetics, tissue distribution, survival rate of the test animals, and antitumor efficacy of the PLGA-LDH-MTX nanoparticles and its counterpart without LDH, PLGA-MTX nanoparticles compared with bare MTX. The median lethal dose (LD₅₀) of the former was higher, compared with bare MTX, using Balb/c nude mice, indicating it to be completely safe for use. Also, a comparative pharmacokinetic and antitumour efficacy study using MTX, PLGA-MTX, and PLGA-LDH-MTX nanoparticles in osteosarcoma-induced Balb/c nude mice in vivo demonstrated superiority of PLGA-LDH-MTX as compared to PLGA-MTX and bare MTX. The results suggest that PLGA-LDH-MTX nanoparticles might exhibit potential advantages over the present-day chemotherapy over bare MTX, for the possibility of treatment of osteosarcoma.

MicroRNA-520b Suppresses Proliferation, Migration, and Invasion of Spinal Osteosarcoma Cells via Downregulation of Frizzled-8

Spinal osteosarcoma (OS) is a malignant tumor that has a poor outcome. MicroRNA-520b (miR-520b) acts as a cancer suppressor in various types of cancer. Because of the limited amount of literature on OS, we aimed to identify the role of miR-520b in OS. The miR-520b level in clinical spinal OS tissues and adjacent nontumor tissues as well as in cell lines was assessed. The effect of miR-520b on cell proliferation, migration, invasion, and frizzled-8 (FZD8) degradation were all evaluated. Alterations of key proteins involved in the Wnt/β-catenin pathway were assessed by Western blot analysis. In the present study, miR-520b was downregulated in human spinal OS tissues and OS cell lines (p < 0.01 or p < 0.001). Overexpression of miR-520b inhibited cell proliferation (p < 0.01 or p < 0.001), migration (p < 0.01), and invasion (p < 0.01). FZD8 expression was negatively regulated by infection with a lentivirus vector carrying an miR-520b precursor in dose- and time-dependent manners. In OS tissues, miR-520b was inversely correlated with FZD8 expression. FZD8 was upregulated in human spinal OS tissues and cell lines. Finally, miR-520b inactivated the Wnt/β-catenin pathway through downregulation of FZD8. miR-520b inhibited cell proliferation, migration, and invasion through inactivating the Wnt/β-catenin pathway by downregulation of FZD8, providing a novel therapeutic target for spinal OS.

Association between the DNA Repair Gene XRCC3 rs861539 Polymorphism and Risk of Osteosarcoma: a Systematic Review and Meta-Analysis

Objective: Although there are a few studies investigating the relation between X-Ray Repair Cross Complementing 3 (XRCC3) gene rs861539 polymorphism and osteosarcoma (OSA), the results are inconsistent. Therefore, we performed this systematic review and meta-analysis to clarify the associations between XRCC3 rs861539 polymorphism and OSA risk. Methods: We have retrieved published literature from PubMed, Google scholar, and ISI Web of Knowledge up to 25 January 2017. Odds ratios were pooled using either fixed-effects or random effects models. Overall and subgroup analyses were performed. Statistical analysis was performed running comprehensive meta-analysis (CMA) 2.0 software. Results: A total of four studies with 515 cases and 1,109 controls were identified in order to investigate the association between XRCC3 rs861539 polymorphism and OSA risk. The results showed that XRCC3 rs861539 polymorphism was associated with OSA in allelic (T vs. C: OR= 1.563, 95% CI: 1.244-1.963, p= <0.001), homozygote (TT vs. CC: OR= 2.574, 95% CI: 1.573-4.212, p= <0.001), dominant (TT+TC vs. CC: OR= 1.255, 95% CI: 1.011-1.558, p= 0.039), and recessive (TT vs. TC+CC: OR= 2.224, 95% CI: 1.393-3.552, p= 0.001), but not with heterozygote (TC vs. CC: OR= 1.361, 95% CI: 0.982-1.885, p= 0.064). The XRCC3 rs861539 polymorphism conferred susceptibility to OSA in Asians, but not in Caucasians. Additionally, we observed no evidence of publication bias. Conclusion: To the best of our knowledge, this is the first meta-analysis investigating the association between XRCC3 rs861539 polymorphism and OSA risk. Our results revealed a significant association between the XRCC3 rs861539 polymorphism and risk of OSA, especially in Asian populations. Future more comprehensive and well-designed case control studies with larger sample size are needed to warrant these findings.

Imaging of presacral masses--a multidisciplinary approach

Our objective is to describe an approach for retrorectal/presacral mass evaluation on imaging with attention to imaging features, allowing for refinement of the differential diagnosis of these masses. Elaborate on clinically relevant features that may affect biopsy or surgical approach, of which the radiologist should be aware. A review of current literature regarding the diagnosis and treatment of retrorectal/presacral masses was performed with attention to specific findings, which may lend refinement to the differential diagnosis of these masses. Cases were obtained by searching through a radiology database at a single institution after Institutional Review Board approval. Recent advances in imaging and treatment methods have led to the increased role of radiology in both imaging and tissue diagnosis of retrorectal masses. Surgical philosophies surrounding the treatment of these masses have not significantly changed in recent years, but there are a few key factors of which the radiologist must be aware. The radiologist can offer refinement of the differential diagnosis of retrorectal masses and can elaborate on salient findings which could alter the need for neoadjuvant chemoradiation therapy, pre-surgical tissue diagnosis and surgical approach. This article presents an imaging approach to retrorectal/presacral masses with emphasis on findings which can dictate the ultimate need for neoadjuvant therapy and pre-surgical tissue diagnosis and alter the preferred surgical approach. This article consolidates key findings, so radiologists can become more clinically relevant in the evaluation of these masses.

Combined modified en bloc corpectomy with replacement of the aorta in curative interdisciplinary treatment of a large osteosarcoma infiltrating the aorta

PURPOSE

We report a case of a large three-level spinal osteosarcoma infiltrating the adjacent aorta. This is the first case in which a combined modified three-level en bloc corpectomy with resection and replacement of the adjacent aorta was successful as a part of interdisciplinary curative treatment.

METHODS

Case report.

RESULTS

The surgical procedure was performed as a two-step treatment. A heart lung machine (HLM) was not used, in order to avoid cerebral and spinal ischemia and to decrease the risk of hematogenous tumor metastases. Instead, a bypass from the left subclavian artery the distal descending aorta was used. We modified the en bloc corpectomy procedure, leaving a dorsal segment of the vertebral bodies to enable rapid surgery. The procedure was successful and the en bloc resection of the vertebral body with aortal resection could be achieved. Except for pallhypesthesia in the left dermatomes Th7-Th10, the patient does not have any postoperative neurologic deficits.

CONCLUSION

Combined corpectomy with aortic replacement should be considered as a reasonable option in the curative treatment of osteosarcoma with consideration of the immense surgical risks. The use of an HLM is not necessary, especially considering the inherent risk of hematogenous tumor metastases. Modified corpectomy leaving a dorsal vertebral body segment was considered a reasonable variation since tumor-free margins could still be expected.

Osteosarcoma: Diagnostic dilemmas in histopathology and prognostic factors

Osteosarcoma (OS), the commonest malignancy of osteoarticular origin, is a very aggressive neoplasm. Divergent histologic differentiation is common in OS; hence triple diagnostic approach is essential in all cases. 20% cases are atypical owing to lack of concurrence among clinicoradiologic and pathologic features necessitating resampling. Recognition of specific anatomic and histologic variants is essential in view of better outcome. Traditional prognostic factors of OS do stratify patients for short term outcome, but often fail to predict their long term outcome. Considering the negligible improvement in the patient outcome during the last 20 years, search for novel prognostic factors is in progress like ezrin vascular endothelial growth factor, chemokine receptors, dysregulation of various micro ribonucleic acid are potentially promising. Their utility needs to be validated by long term followup studies before they are incorporated in routine clinical practice.