Primary Bone Tumors Research Articles

UK guidelines for the management of bone sarcomas.

This document is an update of the British Sarcoma Group guidelines (2016) and provides a reference standard for the clinical care of UK patients with primary malignant bone tumours (PMBT) and giant cell tumours (GCTB) of bone. The guidelines recommend treatments that are effective and should be available in the UK, and support decisions about management and service delivery. The document represents a consensus amongst British Sarcoma Group members in 2024. Key recommendations are that bone pain, or a palpable mass should always lead to further investigation and that patients with clinical or radiological findings suggestive of a primary bone tumour at any anatomic site should be referred to a specialist centre and managed by an accredited bone sarcoma multidisciplinary team. Treatment recommendations are provided for the major tumour types and for localised, metastatic and recurrent disease. Follow-up schedules are suggested.

Bone marrow mesenchymal stem cell-derived exosomes improve cancer drug delivery in human cell lines and a mouse osteosarcoma model

IntroductionOsteosarcoma is the most common primary bone tumor. Patients require chemotherapy drugs with high-targeting ability and low off-target toxicity to improve their survival. Exosomes are biological vesicles that mediate long-distance communication between cells and naturally target their source sites. Exosomes derived from bone marrow mesenchymal stem cells (BMSCs) naturally target bone tumor sites, suggesting their potential as effective anti-tumor therapy vectors. In this study, we evaluated the potential of BMSC-derived exosomes in targeting osteosarcoma and serving as a carrier for doxorubicin (DOX).MethodsWe isolated exosomes from human BMSCs and synthesized hybrid exosomes (HEs) by fusing these exosomes with liposomes. These HEs were loaded with DOX to produce a novel drug, HE/DOX.ResultsWe confirmed the successful synthesis of HE/DOX using fluorescence spectroscopy and estimated its size to be 151.1 ± 10.2 nm. HEs expressed the known exosomal proteins ALIX, CD63, and TSG101. Under acidic conditions similar to those observed in the tumor microenvironment, the drug release from HE/DOX was enhanced. In osteosarcoma cell lines and in a mouse osteosarcoma model, HE/DOX exhibited stronger tumor-inhibitory effects than free DOX.ConclusionsOur study demonstrates that BMSC-derived exosomes could effectively target osteosarcoma. Furthermore, HEs can serve as effective carriers of DOX, enabling the treatment of osteosarcoma. These findings highlight a promising direction for tumor-targeted therapy.

The Interplay Between the MYC Oncogene and Ribosomal Proteins in Osteosarcoma Onset and Progression: Potential Mechanisms and Indication of Candidate Therapeutic Targets

High-grade osteosarcoma (OS) is the most common primary bone tumor mainly affecting children and young adults. First-line treatment consists of neo-adjuvant chemotherapy with doxorubicin, cisplatin, and methotrexate and surgery. The mean long-term survival rate for localized disease at diagnosis is 65–70%, dropping down to 20% when metastases are present at diagnosis. Therefore, curing OS is a clinical challenge, particularly for patients that do not respond to standard treatments. MYC has frequently been reported to be involved in the pathogenesis of OS and its high expression may be associated with drug resistance and patients’ worse prognosis. Moreover, MYC is a master regulator of ribosomal proteins (RPs) synthesis and ribosome biogenesis (RiBi), which is often up-regulated in human tumors. In recent years, RPs have been recognized not only for their traditional role in ribosome assembly but also for their extra-ribosomal functions, many of which are linked to the onset and progression of cancer. In this review we focus on the role and possible interplay of MYC and RPs expression in association with drug resistance and worse prognosis in OS and discuss therapeutic options that target de-regulated MYC, RiBi, or RPs, which are already clinically available or under evaluation in clinical trials.

024. Case Report: Giant Cell Tumor Intravertebra

Background: Giant cell tumor is a rare neoplasm that most frequently occurs at the end of long bones and accounts for approximately 5% of all primary bone tumors in adults. The prevalence of spinal giant cell tumors is estimated at 2%–15% of all spinal giant cell tumors. However, Giant cell tumor is a rare finding in the spine, especially in the pediatric population. Case: A 6-year-old male patient presented with back pain that had spread to both legs for 1.5 years and had worsened in the past 4 months. The pain is intermittent. The patient also felt tingling in the waist and legs, which then turned into a thickening feeling from the waist to the toes since the last 6 months. The patient also complained of weakness in both legs since 1 year ago. Currently the patient is only on bed rest. The patient cannot walk but can still stand with assistance. Defecation and urination remain within normal limits. History of previous trauma (-) Prolonged cough (-), bed wetting (-), headache (-), seizures (-), decreased consciousness (-), progressive weight loss (-), nausea (-) vomiting (-), history of contact with TB sufferers (-). Conclusion: Complete resection of tumor by laminectomy was performed successfully followed by spinal fusion with a pedicle screw. The screws were placed correctly at all four levels of Vertebrae. The decision was made to give stability for spine and it was scheduled to remove the pedicle screw one year follow-up after surgery. Histopathology results showed characteristic findings of giant cell tumor.

Arthroscopic Management of Juxta-Articular Proximal Tibial Chondroblastoma: A Case Report and Literature Review.

Chondroblastoma is a rare bone tumor that originates from the epiphysis, constitutes around 1% of all primary bone tumors and is recognized for its tendency to exhibit local invasiveness, as well as the possibility of metastasis and recurrence in nearby areas. Currently, the main surgical treatment for chondroblastoma is open surgery, involving excision of the lesion. There are relatively few reports on arthroscopic surgery for the treatment of chondroblastoma. However, open surgical curettage is associated with operation-related trauma and potential for damage to the osteoepiphysis resulting in growth disturbances. This case study presents the application of an arthroscopic technique in a 14-year-old male patient with chondroblastoma affecting the proximal tibia and tibial eminence. The procedure involved thorough removal of the lesion using direct visualization with the management of the cavity utilizing a substitute for autologous bone graft. After 1 year of follow-up, the patient remains free from symptoms, exhibits normal knee functionality, and radiographic analysis reveals a good autologous bone graft fusion without any signs of recurrence. Based on the existing cases of arthroscopic treatment for chondroblastoma and the report of this case, arthroscopic treatment for chondroblastoma can be considered as a specific treatment option for certain patients. In some cases, this technique could be an effective alternative to open surgery.

CORR Insights®: What Are the Complications, Reconstruction Survival, and Functional Outcomes of Modular Prosthesis and Allograft-prosthesis Composite for Proximal Femur Reconstruction in Children With Primary Bone Tumors?

CORR Insights®: What Are the Complications, Reconstruction Survival, and Functional Outcomes of Modular Prosthesis and Allograft-prosthesis Composite for Proximal Femur Reconstruction in Children With Primary Bone Tumors?

Plating after tumor curettage in human femora does not efficiently improve torsional stability ex vivo

BackgroundSurgical treatments of benign primary bone tumors of the femur face the challenge of limiting tissue damage and contamination while providing sufficient stabilization to avoid fracture. While no clear treatment guidelines exist, surgical treatment commonly consists of femoral fenestration and curettage with optional filling and plating of the defect. Mono- or bicortical plating of distal femoral defects aim to reduce fracture risk and have been shown to increase axial stability. However, it remains unclear whether plating increases torsional stability of the affected femur. Questions/purposesThis biomechanical study aimed to determine how much additional stability can be achieved by mono- or bicortical plating of femoral defects after fenestration. The following hypotheses were investigated: 1. Preventive plating of distal femur bone defects enhances torsional stability when compared to femoral fenestration alone. 2. A condition close to the intact (nonpathological) bone can be achieved by bone plating. 3. Defect shape influences torsional stability. Patients and methodsThiel embalmed human femora (n = 24) were left intact or subjected to the following surgical treatments (A) defect creation via fenestration, (B) defect with short monocortical plating, (C) defect with long bicortical plating. All femora were torsion tested in midstance position using pre-cycling and testing until failure. Quantitative computed tomography pre and post testing allowed bone mineral density calculation and crack path analysis. Finite element analysis provided insight into defect shape variations. ResultsTorsion experiments showed no relevant enhancement of torsional stability due to mono- or bicortical plating. There were no significant differences in maximum torque between unplated and plated femora with defect (defect: 35.38 ± 7.53 Nm, monocortical plating: 37.77 ± 9.82 Nm, bicortical plating: 50.27 ± 9.72 Nm, p > 0.05). Maximum torque for all treatment groups was significantly lower compared to intact femora (155–200 Nm, p < 0.001). Cracks originated predominantly from the proximal posterior corner of the defect and intersected with screw holes in plated femora. The influence of variations of the defect corner shapes had no significant influence on maximum torque and angle. ConclusionThis biomechanical study shows that mono- or bicortical plating is not an effective preventive treatment against torsional failure of femora with distal defects as the resulting maximum torque was drastically reduced compared to intact femora. Thus, the initial hypotheses have to be rejected. As habitual loading of the femur includes a combination of axial and torsional loading, the observed lack of prevention against torsional failure might help to explain the occurrence of fractures despite plating. Future research towards ameliorating clinical outcome should address the role of defect filling with bone cement or bone grafts regarding the improvement of torsional stability after primary bone tumor treatment in the femur.

COMPARATIVE ANALYSIS OF THE DIAGNOSTIC ACCURACY OF ENDOSTATIN AND VEGF SERUM LEVELS IN PATIENTS WITH BONE SARCOMAS

Introduction. Angiogenesis regulators are of particular interest as new serum markers in cancer patients, since they reflect the intensity of tumor growth and metastasis. Currently, many works are dedicated to the study of vascular endothelial growth factor (VEGF), which activates angiogenesis, and endostatin, which inhibits it. However, a comparative study of the diagnostic accuracy of serum levels of these two markers in patients with bone sarcomas has not been conducted yet. Аim. A comparative analysis of the diagnostic accuracy indicators and prognostic significance of VEGF and endostatin in the blood serum of patients with primary malignant bone tumors. Methods. During the study, the levels of endostatin and VEGF in blood serum samples from 123 patients with a newly diagnosed and morphologically verified bone sarcoma were measured. Patients were examined at the Federal State Budgetary Institution “National Medical Research Center of Oncology named after N.N. Blokhin” of the Russian Ministry of Health from July 2001 to December 2022. Sixty age- and gender-matched healthy donors were included in the control group. Results. Median serum concentrations of endostatin and VEGF in the patient group were statistically significantly increased compared to the control group by 1.3 and 1.4 times, respectively (p &lt; 0.01). Statistically significant differences in the serum concentrations of VEGF and endostatin depending on the T category and the tumor grade and stage were not identified. The cut-off value of VEGF was 279 pg/ml, and the cut-off value of endostatin was 121 ng/ml. With the same sensitivity of 75.6%, endostatin is characterized by higher specificity than VEGF (73.0 and 67.6%, respectively). The proportional hazards model characterizing the effect of serum VEGF and endostatin levels on overall and survival was not statistically significant. Conclusion. Endostatin in the blood serum of patients with bone tumors is more informative compared to VEGF; however, both markers are not predictors of overall and survival.

Shared decision making in primary malignant bone tumour surgery around the knee in children and young adults: protocol for a prospective study

BackgroundChildren and young adults needing surgery for a primary malignant bone tumour around the knee face a difficult, life-changing decision. A previous study showed that this population wants to be involved more in the decision-making process and that more involvement leads to less decisional stress and regret. Therefore, a well-designed and standardized decision-making process based on the principles of shared decision-making needs to be designed, implemented, and evaluated.MethodsWe developed a shared decision-making (SDM) model for this patient population, including an online decision aid (DA). This model has been implemented in the standard care of patients with a primary malignant bone tumour around the knee. Following implementation, we will analyse its effect on the decision-making process and the impact on patient experiences using questionnaires and interviews. Moreover, potential areas for improvement will be identified.DiscussionGiven the importance of involving patients and parents in surgical decision-making, particularly in life-changing surgery such as malignant bone tumour surgery, and given the lack of SDM models applicable for this purpose, we want to share our model with the international community, including our study protocol for evaluating and optimising the model. This study will generate valuable knowledge to facilitate the optimisation of current patient care for local treatment. The sharing of our implementation and study protocol can serve as an example for other centres interested in implementing SDM methods in an era characterized by more empowered patients and parents who desire autonomy and reliable and realistic information.

Positron emission tomography-magnetic resonance imaging applications in pediatric musculoskeletal tumors.

The hybrid imaging positron emission tomography/magnetic resonance (PET/MR) is an important tool in the management of pediatric oncology patients, particularly in malignant musculoskeletal pathologies, because it combines the functional and metabolic information of tumor provided by PET with the high soft-tissue contrast and the functional information offered by magnetic resonance imaging (MRI). We performed an observational retrospective study that included pediatric patients diagnosed with primary bone or soft-tissue sarcomas in the Pediatric Hematology and Oncology Unit at the HM Montepríncipe University Hospital, Boadilla del Monte, Madrid (Spain) who underwent whole-body 18F-fluorodeoxyglucose (18F-FDG) PET/MRI as a staging study and for follow-up evaluation for treatment response from September 2017 to January 2023. This study explores the protocols, the practical application of the PET/MRI technique and our clinical experience at our center in the diagnosis and follow-up of primary bone tumors and soft-tissue sarcomas in children. Seventy-one 18F-PET/MR studies were performed on 39 patients. Most of them (55%) were initial extension studies and (45%) were follow-up studies. Most of the patients studied were male (74.4%) with a median age of 15 years. Of the 39 cases, 51% were primary bone tumors while 18% were Langerhans cell histiocytosis and 21% soft tissue tumors. Of the 71 studies, five showed metastases at the initial diagnosis, three presented lymph node involvement, one with local infiltration, and one with pulmonary metastasis. PET/MR has represented a significant advancement in the evaluation of pediatric malignant neoplasms, with specific applications in musculoskeletal tumors showing clear benefits over PET/CT. The primary advantage is the reduction in ionizing radiation doses and the assessment of soft tissues, making it an excellent option for malignant musculoskeletal pathologies in pediatric patients who often require long-term follow-up. It is particularly useful for early tumor detection and functional therapy monitoring in oncology. The development of new protocols is making studies increasingly faster and better tolerated, even without the need for anesthesia. PET/MRI has shown to increase diagnostic accuracy in primary bone and soft tissue tumors, as it allows for the comprehensive evaluation of their morpho-metabolic characteristics, locoregional, and distant involvement in a single study. It is also useful in surgical planning and post-treatment follow-up.

M2 macrophage exosome-derived Apoc1 promotes ferroptosis resistance in osteosarcoma by inhibiting ACSF2 deubiquitination.

Osteosarcoma (OS) is the most common primary malignant tumor of bone. The aim of this study was to investigate the regulatory mechanisms of M2 macrophage exosomes (M2-Exos) in ferroptosis in OS. A mouse model was established to investigate the in vivo role of M2-Exos. We investigated their effects on ferroptosis in OS using erastin, a ferroptosis activator, and deferoxamine mesylate, an iron chelator. In vitro, we investigated whether the Apoc1/Acyl-CoA Synthetase Family Member 2 (ACSF2) axis mediates these effects, using shApoc1 and shACSF2. The mechanisms whereby Apoc1 regulates ACSF2 were examined using cyclohexanone, a protein synthesis inhibitor, and MG132, a proteasomal inhibitor. M2-Exos reversed the inhibitory effects of erastin on OS cells, thus enhancing their viability, migration, invasion, proliferation, and reducing ferroptosis. Apoc1 was highly expressed in M2-Exos, and interfering with this expression reversed the effects of M2-Exos on OS cells. ACSF2 mediated the effects of M2-Exos-derived Apoc1. Apoc1 interacted with ACSF2, which, in turn, interacted with USP40. Apoc1 overexpression increased ACSF2 ubiquitination, promoting its degradation, whereas USP40 overexpression inhibited ACSF2 ubiquitination and promoted its expression. Apoc1 overexpression inhibited ACSF2 binding to USP40. M2-Exos-derived Apoc1 promoted ferroptosis resistance by inhibiting USP40 binding to ACSF2 and promoting ACSF2 ubiquitination and degradation, thus enhancing OS development.

AI based diagnostics product design for osteosarcoma cells microscopy imaging of bone cancer patients using CA-MobileNet V3

ObjectiveThe incidence of osteosarcoma (OS) is low, but primary malignant bone tumors rank third among the causes of death in cancer patients under the age of 20. Currently, analysis of cellular structure and tumor morphology through microscopic images remains one of the main diagnostic methods for osteosarcoma. However, this completely manual approach is tedious, time-consuming, and difficult to diagnose accurately due to the similarities in certain characteristics of malignant and benign tumors. MethodsLeveraging the potential of artificial intelligence (AI) in assessing and classifying images, this study explored a modified CA-MobileNet V3 model that was embedded into innovative microscope products to enhance the microscope’s feature extraction capabilities and help reduce misclassification during diagnosis. ResultsThe intelligent recognition model method introduced in this paper has significant advantages in retrieval and classification of osteosarcoma cells and other cell types. Compared with models such as ShuffleNet V2, EfficientNet V2, Mobilenet V3 (without transfer learning), TL-MobileNet V3 (with transfer learning), etc., the model size is only 5.33 MB, is a lightweight model, and the accuracy of the improved model reached 98.69 %. In addition, the artificial intelligence microscope (AIM) with integrated design based on this model can also help improve diagnostic efficiency. ConclusionThe innovative method of the CA-MobileNet V3 automatic classification model based on deep learning provides an efficient and reliable solution for the pathological diagnosis of osteosarcoma. This study contributes to medical image analysis and provides doctors with an accurate and valuable tool for microscopic diagnosis. It also promotes the advancement of artificial intelligence in medical imaging technology.

Reconstruction after proximal ulnar resection.

Reconstruction after osteoarticular resection of the proximal ulna for tumours is technically difficult and little has been written about the options that are available. We report a series of four patients who underwent radial neck to humeral trochlea transposition arthroplasty following proximal ulnar osteoarticular resection. Between July 2020 and July 2022, four patients with primary bone tumours of the ulna underwent radial neck to humeral trochlea transposition arthroplasty. Their mean age was 28 years (12 to 41). The functional outcome was assessed using the range of motion (ROM) of the elbow, rotation of the forearm and stability of the elbow, the Musculoskeletal Tumor Society score (MSTS), and the nine-item abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH-9) score. All patients were available for follow-up at a mean of 33 months (25 to 43) and were disease-free. The mean flexion arc was 0° to 105°. Three patients had complications. One had neuropraxia of the ulnar nerve. The symptoms resolved after three months. In one patient, the screw used for fixation of the triceps tendon became exposed and was removed, six months postoperatively. One patient with wound dehiscence required a local flap for soft-tissue cover, four months postoperatively. At a mean follow-up of 33 months (25 to 43), the mean flexion arc was 0° to 105°. All patients had full supination (85°) but none had any pronation. The mean MSTS score was 23.5 (23 to 24) and mean QuickDASH-9 score was 26.13 (16.5 to 35.75). Three patients had varus-valgus instability on examination, although only one had a sense of instability while working. Radial neck to humeral trochlea transposition offers a satisfactory and cost-effective biological reconstructive option after osteoarticular resection of the proximal ulna, in the short term. It provides good elbow function and, being a biological reconstruction option using native bone, is likely to provide long-term stability and durability.

A novel adjunctive diagnostic method for bone cancer: Osteosarcoma cell segmentation based on Twin Swin Transformer with multi-scale feature fusion

BackgroundOsteosarcoma, the most common primary bone tumor originating from osteoblasts, poses a significant challenge in medical practice, particularly among adolescents. Conventional diagnostic methods heavily rely on manual analysis of magnetic resonance imaging (MRI) scans, which often fall short in providing accurate and timely diagnosis. This underscores the critical need for advancements in medical imaging technologies to improve the detection and characterization of osteosarcoma. MethodsIn this study, we sought to address the limitations of current diagnostic approaches by leveraging Hoechst-stained images of osteosarcoma cells obtained via fluorescence microscopy. Our primary objective was to enhance the segmentation of osteosarcoma cells, a crucial step in precise diagnosis and treatment planning. Recognizing the shortcomings of existing feature extraction networks in capturing detailed cellular structures, we propose a novel approach utilizing a twin swin transformer architecture for osteosarcoma cell segmentation, with a focus on multi-scale feature fusion. ResultsThe experimental findings demonstrate the effectiveness of the proposed Twin Swin Transformer with multi-scale feature fusion in significantly improving osteosarcoma cell segmentation. Compared to conventional techniques, our method achieves superior segmentation performance, highlighting its potential utility in clinical settings. ConclusionThe development of our Twin Swin Transformer with multi-scale feature fusion method represents a significant advancement in medical imaging technology, particularly in the field of osteosarcoma diagnosis. By harnessing advanced computational techniques and leveraging high-resolution imaging data, our approach offers enhanced accuracy and efficiency in osteosarcoma cell segmentation, ultimately facilitating better patient care and clinical decision-making.

Trends in Location of Death for Individuals With Primary Bone Tumors in the United States.

Given the significant morbidity and mortality associated with primary bone cancer, provision of high-quality end-of-life care concordant with patient preferences is critical. This study aimed to evaluate trends in use of dedicated end-of-life care settings and investigate sociodemographic disparities in location of death among individuals with primary bone cancer. A retrospective, population-based review of patients who died of primary bone cancer-related causes was performed using the Underlying Cause of Death public use record from the Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research (WONDER) database for the years 2003 through 2019. A total of 24,557 patients were included. Over the study period, the proportion of primary bone cancer-related deaths occurring at home and in hospice increased, whereas those occurring in hospital, nursing home, and outpatient medical facility/emergency department settings decreased. Several sociodemographic factors were found to be associated with location of death, including age, marital status, and level of education. Moreover, patients of racial and ethnic minority groups were at significantly lower risk of experiencing death at home or in outpatient medical facility/emergency department settings relative to a hospital compared with White patients. Although rates of in-hospital death from primary bone cancer are decreasing, marked racial and ethnic disparities in use of dedicated end-of-life care settings exist. These gaps must be addressed to ensure all patients with primary bone cancer have equitable access to high-quality end-of-life care regardless of racial, ethnic, or socioeconomic status. [Orthopedics. 202x;4x(x):xx-xx.].

Effects of Neoadjuvant Denosumab on Radiological and Histological Responses in Patients Undergoing En Bloc Resection for Giant Cell Tumor of Bone: A Systematic Review

Background: Giant cell tumor of bone (GCTB) is a rare primary bone tumor. The standard treatment is en bloc resection, which can be challenging due to tumor size or location. Denosumab, a monoclonal antibody, has emerged as a promising neoadjuvant therapy for GCTB, potentially facilitating surgical resection. However, its optimal use remains unclear, with debate surrounding its impact on local recurrence. This systematic review aims to synthesize evidence on the histological and radiological changes induced by neoadjuvant denosumab and its impact on surgical outcomes. Methods: This review followed PRISMA guidelines. The medical term "denosumab", "neoadjuvant", "GCTB", "radiological", and "histological" were used in PubMed (423 articles) and Google Scholar (18,100 articles), totaling 18,523 articles to discover studies of the effect of neoadjuvant denosumab on radiological and histological response up to July 2023. Six remaining studies were reviewed and screened for inclusion criteria based on their relevance to the study subject and clinical outcomes. Results: Based on six studies in this review, five showed histological response by decreasing the multinucleated giant cells and osteoclasts after neoadjuvant DT. Six studies showed increased significant bone reconstitution as a radiological response in the GCTB locale, replaced the extending tumor into soft tissue by abundant bone production with peripheral shell, and increased ease of en bloc resection. Conclusions: Neoadjuvant denosumab therapy shows promise in managing giant cell tumors of bone (GCTB) by reducing osteoclasts, shrinking tumor volume, and promoting cortical bone formation, thus facilitating en bloc resection. However, further research is needed to confirm these findings.

Primary Bone Tumors and Breast Cancer-Induced Bone Metastases: In Vivo Animal Models and New Alternative Approaches

Bone is the preferential site of metastasis for the most common tumors, including breast cancer. On the other hand, osteosarcoma is the primary bone cancer that most commonly occurs and causes bone cancer-related deaths in children. Several treatment strategies have been developed so far, with little or no efficacy for patient survival and with the development of side effects. Therefore, there is an urgent need to develop more effective therapies for bone primary tumors and bone metastatic disease. This almost necessarily requires the use of in vivo animal models that better mimic human pathology and at the same time follow the ethical principles for the humane use of animal testing. In this review we aim to illustrate the main and more suitable in vivo strategies employed to model bone metastases and osteosarcoma. We will also take a look at the recent technologies implemented for a partial replacement of animal testing.

Osteosarcoma with Pathological Fracture: A Rare Case Report

Introduction: Osteosarcoma is a primary malignant bone tumor originating from stem cells and is characterized by the proliferation of tumor cells that directly form immature bone or bone-like tissue. Osteosarcoma represents only 3% to 5% of all spinal malignancies. The aim of study is to discuss the importance of diagnostic investigation for a relatively rare case of spinal osteosarcoma. Case presentation: A 49 years old female came to the Emergency Unit, with a chief complaint of bilateral weakness of lower extremities for 1 year and worsening in 2 weeks. Upon examination, the initial diagnosis was mistaken for a spinal canal stenosis because metastatic bone disease from previous history of malignant melanoma. Subsequently, a decompression with stabilization fusion and biopsy is performed. Primary osteosarcoma was confirmed from histopathology results. Further chemotherapy is planned referring to confirmed primary osteosarcoma on histopathology. Discussion: Spinal osteosarcoma is very rare. Osteosarcoma occurs most frequently in the appendicular skeleton, especially the distal femur and proximal tibial metaphysis, which account for 90% of all cases. Primary osteosarcomas of the vertebral column are uncommon and occur dominantly in the vertebral body. Biopsy remains the gold standard of care for diagnosis. Conclusion: The performance of MRI and pathologic evaluation with immunohistochemistry is particularly important for the differential diagnosis of soft tissue tumors. Histopathologic analysis also plays an important role in differentiating from metastatic bone disease. An aggressive treatment plan and long-term follow-up are mandatory in managing this case. Keywords: osteosarcoma, spinal osteosarcoma, spinal canal stenosis, malignancy, pathological fracture, rare case.

Honokiol inhibits human osteosarcoma MG63 cell migration by upregulating FTO and Smad6 to promote autophagy

BackgroundOsteosarcoma (OS) is a common primary malignant tumor of bone, most commonly seen in children and adolescents, which has a low survival rate and is a serious threat to patients' lives. Honokiol (HKL) is the main active components of Magnolia officinalis, which have significant anti-tumor properties. The aim of this study was to observe the autophagic and migratory effects of HKL on MG63 cells and to investigate whether the mechanism of action was related to FTO and Smad6. MethodsFirstly, we cultured MG63 cells in vitro and intervened with different concentrations of HKL to detect cell activity by CCK8, apoptosis by flow cytometry, cell migration ability by scratch assay, cell invasion ability by transwell assay and MMP2, P62, LC3 I/II, FTO and Smad6 protein expression by Western blot. ResultsHKL inhibited MG63 cells activity and that this effect was dose and time dependent. Although there was no significant effect on apoptosis and invasive ability, HKL could act through effects such as promoting cell autophagy and inhibiting migration. HKL increased the protein expression levels of FTO, Smad6, MMP2, LC3 I/II and P62, and this effect was reduced after silencing of Smad6. ConclusionsHKL induced autophagy and inhibited cell migration in MG63 cells by increasing the expression of FTP and Smad6. It can be seen that HKL may be a promising drug for the treatment of OS.

Results of endoprosthesis of the elbow joint in patients with tumors of forming it bones

Background. The use of both individual and modular oncological endoprostheses of the elbow joint is possible with primary and secondary (metastatic) tumor lesions of the bones forming it. The purpose of the study was to assess the effectiveness of restoring the function of the elbow joint and the upper limb and improving the quality of life of the patient after endoprosthesis of the elbow joint due to tumors of the bones forming it. ­Material and methods. The results of the treatment of 14 patients who underwent endoprosthesis of the elbow joint due to tumors of the bones forming it were evaluated. Endoprosthesis was performed in 9 (64.3 %) subjects with primary bone tumors and in 5 (35.7 %) patients with metastatic tumors. Reconstruction of the elbow joint was performed with individual oncological endoprostheses in 10 (71.4 %) subjects and modular oncological endoprostheses in 4 (28.6 %) ones. Reconstruction was primary in 12 (85.7 %) patients and secondary in 2 (14.3 %) ones. Results. Du­ring follow-up, 4 (28.6 %) patients died from the progression of the main disease with an ave­rage follow-up period of 24.8 ± 11.9 months, the other 10 (71.4 %) were alive, with an average follow-up period of 80.8 ± 10.3 months. In the early postoperative period, the following complications were observed: neuropathy of the ulnar nerve in 1 (7.1 %) patient. In the late postoperative period, 1 (7.1 %) patient had an infectious complication after 14 months. 1 (7.1 %) subject developed aseptic loose­ning of the humeral leg of the endoprosthesis 12 months after endoprosthesis. In 1 (7.1 %) subjects with a metastatic tumor, local recurrence of the tumor was observed 9 months after surgery. Mean MEPS and MSTS functional scores were 80 and 72 %, respectively. The patients’ quality of life (according to the EORTQ-QLQ-С30 questionnaire) increased from 40 points in the preoperative period to 84 points after elbow joint replacement. Conclusions. Endoprosthesis of the elbow joint in the schemes of complex and combined treatment of primary and metastatic tumors of the bones forming it helps to improve the quality of life of this contingent of patients.