The 2020 WHO Classification of Tumors of Bone: An Updated Review

Sarcoma_CellminerCDB: A tool to interrogate the genomic and functional characteristics of a comprehensive collection of sarcoma cell lines

Sarcomas are a diverse group of rare malignancies composed of multiple different clinical and molecular subtypes. Due to their rarity and heterogeneity, basic, translational, and clinical research in sarcoma has trailed behind that of other cancers. Outcomes for patients remain generally poor due to an incomplete understanding of disease biology and a lack of novel therapies. To address some of the limitations impeding preclinical sarcoma research, we have developed Sarcoma_CellMinerCDB, a publicly available interactive tool that merges publicly available sarcoma cell line data and newly generated omics data to create a comprehensive database of genomic, transcriptomic, methylomic, proteomic, metabolic, and pharmacologic data on 133 annotated sarcoma cell lines. The reproducibility, functionality, biological relevance, and therapeutic applications of Sarcoma_CellMinerCDB described herein are powerful tools to address and generate biological questions and test hypotheses for translational research. Sarcoma_CellMinerCDB (https://discover.nci.nih.gov/SarcomaCellMinerCDB) aims to contribute to advancing the preclinical study of sarcoma.

Advances in drug resistance of osteosarcoma caused by pregnane X receptor

Osteosarcoma (OS) is a prevalent malignancy among adolescents, commonly manifesting during childhood and adolescence. It exhibits a high degree of malignancy, propensity for metastasis, rapid progression, and poses challenges in clinical management. Chemotherapy represents an efficacious therapeutic modality for OS treatment. However, chemotherapy resistance of OS is a major problem in clinical treatment. In order to treat OS effectively, it is particularly important to explore the mechanism of chemotherapy resistance in OS.The Pregnane X receptor (PXR) is a nuclear receptor primarily involved in the metabolism, transport, and elimination of xenobiotics, including chemotherapeutic agents. PXR involves three stages of drug metabolism: stage I: drug metabolism enzymes; stage II: drug binding enzyme; stage III: drug transporter.PXR has been confirmed to be involved in the process of chemotherapy resistance in malignant tumors. The expression of PXR is increased in OS, which may be related to drug resistance of OS. Therefore, wereviewed in detail the role of PXR in chemotherapy drug resistance in OS.

Diagnostic performance and inter-reader reliability of bone reporting and data system (Bone-RADS) on computed tomography

OBJECTIVE

To evaluate the diagnostic performance and inter-reader reliability of the Bone Reporting and Data System (Bone-RADS) for solitary bone lesions on CT.

MATERIALS AND METHODS

This retrospective analysis included 179 patients (mean age, 56 ± 18 years; 94 men) who underwent bone biopsies between March 2005 and September 2021. Patients with solitary bone lesions on CT and sufficient histopathology results were included. Two radiologists categorized the bone lesions using the Bone-RADS (1, benign; 4, malignant). The diagnostic performance of the Bone-RADS was calculated using histopathology results as a standard reference. Inter-reader reliability was calculated.

RESULTS

Bone lesions were categorized into two groups: 103 lucent (pathology: 34 benign, 12 intermediate, 54 malignant, and 3 osteomyelitis) and 76 sclerotic/mixed (pathology: 46 benign, 2 intermediate, 26 malignant, and 2 osteomyelitis) lesions. The Bone-RADS for lucent lesions had sensitivities of 95% and 82%, specificities of 11% and 11%, and accuracies of 57% and 50% for readers 1 and 2, respectively. The Bone-RADS for sclerotic/mixed lesions had sensitivities of 75% and 68%, specificities of 27% and 27%, and accuracies of 45% and 42% for readers 1 and 2, respectively. Inter-reader reliability was moderate to very good (κ = 0.744, overall; 0.565, lucent lesions; and 0.851, sclerotic/mixed lesions).

CONCLUSION

Bone-RADS has a high sensitivity for evaluating malignancy in lucent bone lesions and good inter-reader reliability. However, it has poor specificity and accuracy for both lucent and sclerotic/mixed lesions. A possible explanation is that proposed algorithms heavily depend on clinical features such as pain and history of malignancy.

High expression of DEC2 distinguishes chondroblastic osteosarcoma and promotes tumour growth by activating the VEGFC/VEGFR2 signalling pathway

Osteosarcoma (OS) is the most common primary malignant bone tumour in children and young adults. Account for 80% of all OS cases, conventional OS are characterized by the presence of osteoblastic, chondroblastic and fibroblastic cell types. Despite this heterogeneity, therapeutic treatment and prognosis of OS are essentially the same for all OS subtypes. Here, we report that DEC2, a transcriptional repressor, is expressed at higher levels in chondroblastic OS compared with osteoblastic OS. This difference suggests that DEC2 is disproportionately involved in the progression of chondroblastic OS, and thus, DEC2 may represent a possible molecular target for treating this type of OS. In the human chondroblastic-like OS cell line MNNG/HOS, we found that overexpression of DEC2 affects the proliferation of the cells by activating the VEGFC/VEGFR2 signalling pathway. Enhanced expression of DEC2 increased VEGFR2 expression, as well as increased the phosphorylation levels at sites Y951 and Y1175 of VEGFR2. On the one hand, activation of VEGFR2Y1175 enhanced cell proliferation through VEGFR2Y1175-PLCγ1-PKC-SPHK-MEK-ERK signalling. On the other hand, activation of VEGFR2Y951 decreased mitochondria-dependent apoptosis rate through VEGFR2Y951-VARP-PI3K-AKT signalling. Activation of these two signalling pathways resulted in enhanced progression of chondroblastic OS. In conclusion, DEC2 plays a pivotal role in cell proliferation and apoptosis-resistance in chondroblastic OS via the VEGFC/VEGFR2 signalling pathway. These findings lay the groundwork for developing focused treatments that target specific types of OS.

Fear of cancer recurrence in adolescent patients with malignant bone tumors: a cross-section survey

BACKGROUND

Adolescent malignant-bone tumor patients' fear of cancer recurrence is a significant psychological issue, and exploring the influencing factors associated with fear of cancer recurrence in this population is important for developing effective interventions. This study is to investigate the current status and factors influencing fear of cancer recurrence (FCR) related to malignant bone-tumors in adolescent patients, providing evidence for future targeted mental health support and interventions.

DESIGN

A cross-sectional survey.

METHODS

In total, 269 adolescent malignant-bone tumor cases were treated at two hospitals in Zhejiang Province, China from January 2023 to December 2023. Patients completed a General Information Questionnaire, Fear of Progression Questionnaire-Short Form (FoP-Q-SF), Family Hardiness Index (FHI), and a Simple Coping Style Questionnaire (SCSQ). Univariate and multivariable logistic regressions analysis were used to assess fear of cancer recurrence.

RESULTS

A total of 122 (45.4%) patients experienced FCR (FoP-Q-SF ≥ 34). Logistic regression analysis analyses showed that per capita-monthly family income, tumor stage, communication between the treating physician and the patient, patient's family relationships, family hardiness a positive coping score, and a negative coping score were the main factors influencing FCR in these patients (P < 0.05).

CONCLUSIONS

FCR in malignant-bone tumor adolescent patients is profound. Healthcare professionals should develop targeted interventional strategies based on the identified factors, which affect these patients; helping patients increase family hardiness, helping patients to positively adapt, and avoid negative coping styles.

Advancing musculoskeletal tumor diagnosis: Automated segmentation and predictive classification using deep learning and radiomics

OBJECTIVES

Musculoskeletal (MSK) tumors, given their high mortality rate and heterogeneity, necessitate precise examination and diagnosis to guide clinical treatment effectively. Magnetic resonance imaging (MRI) is pivotal in detecting MSK tumors, as it offers exceptional image contrast between bone and soft tissue. This study aims to enhance the speed of detection and the diagnostic accuracy of MSK tumors through automated segmentation and grading utilizing MRI.

MATERIALS AND METHODS

The research included 170 patients (mean age, 58 years ±12 (standard deviation), 84 men) with MSK lesions, who underwent MRI scans from April 2021 to May 2023. We proposed a deep learning (DL) segmentation model MSAPN based on multi-scale attention and pixel-level reconstruction, and compared it with existing algorithms. Using MSAPN-segmented lesions to extract their radiomic features for the benign and malignant classification of tumors.

RESULTS

Compared to the most advanced segmentation algorithms, MSAPN demonstrates better performance. The Dice similarity coefficients (DSC) are 0.871 and 0.815 in the testing set and independent validation set, respectively. The radiomics model for classifying benign and malignant lesions achieves an accuracy of 0.890. Moreover, there is no statistically significant difference between the radiomics model based on manual segmentation and MSAPN segmentation.

CONCLUSION

This research contributes to the advancement of MSK tumor diagnosis through automated segmentation and predictive classification. The integration of DL algorithms and radiomics shows promising results, and the visualization analysis of feature maps enhances clinical interpretability.

Establishing biomarkers for soft tissue sarcomas

INTRODUCTION

Soft tissue sarcomas (STS) are a rare and diverse group of tumors. Curative options are limited to localized disease, with surgery being the mainstay. Advanced stages are associated with a poor prognosis. Currently, the prognosis of the patient is based on histological classification and clinical characteristics, with only a few biomarkers having entered clinical practice.

AREAS COVERED

This article covers extensive recent research that has established novel potential biomarkers based on genomics, proteomics, and clinical characteristics. Validating and incorporating these biomarkers into clinical practice can improve prognosis, prediction of recurrence, and treatment response. Relevant literature was collected from PubMed, Scopus, and clinicaltrials.gov databases (November 2023).

EXPERT OPINION

Currently, defining prognostic markers in soft tissue sarcomas remains challenging. More studies are required, especially to personalize treatment through advanced genetic profiling and analysis using individual tumor and patient characteristics.

Extra-skeletal intracranial mesenchymal chondrosarcoma: systematic-literature review

BACKGROUND

Intracranial mesenchymal chondrosarcoma (IMC) is a rare malignant tumor in pediatric population. IMC can present as extra- or intra-axial lesion in pediatric patients, though the former is commoner causing raised intracranial pressure (ICP). Radiological diagnosis is a challenge in these cases, as is it difficult to differentiate these from other extra-axial neoplasms due to the wide differential diagnosis in pediatric population. We aim to systematically review the literature and present a rare case of extraskeletal intracranial mesenchymal chondrosarcoma treated with safe maximal resection.

METHODS

A systematic review of literature was conducted in accordance with PRISMA guidelines. PubMed and Scopus databases were queried using the search terms, "primary intracranial chondrosarcoma", "extraskeletal mesenchymal chondrosarcoma", "mesenchymal chondrosarcoma" and "pediatric". Presentation, surgical management and outcome of a 15-year-old male with an extraskeletal IMC are also described.

RESULTS

The search yielded 25 articles which met the inclusion criteria. These published records consisted of 33 IMC cases with mean age at presentation of 9.81 ± 5.2 years (range 2 months to 18 years). Frontal region was the commonest locations (11, 33.3%). Most common presentation was headache (14, 42.4%). All patients underwent surgical intervention: gross total resection (20, 60.6%), subtotal resection (9, 27.3%) and no extent mentioned (4, 12.1%). No adjuvant therapy was received in 15 patients (45.5%). On latest follow-up, 11 patients (33.3%) are on remission, 5 patients (15.2%) are symptom free, 3 patients (9.1%) had recurrence, 2 patients (6.1%) had metastasis and 9 patients (27.3%) expired.

CONCLUSION

IMC is a rare entity in pediatric population with imaging findings which are non-characteristic leading to its diagnostic challenge. It can masquerade as other extra-axial intracranial neoplasm (meningioma or hemangiopericytoma). Combination of clinico-radiological and pathological examination can help in accurate diagnosis.  Safe Maximal resection followed by radiotherapy is the preferred treatment strategy.

Chondrosarcoma evaluation using hematein-based x-ray staining and high-resolution 3D micro-CT: a feasibility study

BACKGROUND

Chondrosarcomas are rare malignant bone tumors diagnosed by analyzing radiological images and histology of tissue biopsies and evaluating features such as matrix calcification, cortical destruction, trabecular penetration, and tumor cell entrapment.

METHODS

We retrospectively analyzed 16 cartilaginous tumor tissue samples from three patients (51-, 54-, and 70-year-old) diagnosed with a dedifferentiated chondrosarcoma at the femur, a moderately differentiated chondrosarcoma in the pelvis, and a predominantly moderately differentiated chondrosarcoma at the scapula, respectively. We combined a hematein-based x-ray staining with high-resolution three-dimensional (3D) microscopic x-ray computed tomography (micro-CT) for nondestructive 3D tumor assessment and tumor margin evaluation.

RESULTS

We detected trabecular entrapment on 3D micro-CT images and followed bone destruction throughout the volume. In addition to staining cell nuclei, hematein-based staining also improved the visualization of the tumor matrix, allowing for the distinction between the tumor and the bone marrow cavity. The hematein-based staining did not interfere with further conventional histology. There was a 5.97 ± 7.17% difference between the relative tumor area measured using micro-CT and histopathology (p = 0.806) (Pearson correlation coefficient r = 0.92, p = 0.009). Signal intensity in the tumor matrix (4.85 ± 2.94) was significantly higher in the stained samples compared to the unstained counterparts (1.92 ± 0.11, p = 0.002).

CONCLUSIONS

Using nondestructive 3D micro-CT, the simultaneous visualization of radiological and histopathological features is feasible.

RELEVANCE STATEMENT

3D micro-CT data supports modern radiological and histopathological investigations of human bone tumor specimens. It has the potential for being an integrative part of clinical preoperative diagnostics.

KEY POINTS

• Matrix calcifications are a relevant diagnostic feature of bone tumors. • Micro-CT detects all clinically diagnostic relevant features of x-ray-stained chondrosarcoma. • Micro-CT has the potential to be an integrative part of clinical diagnostics.

Survival analysis and prognostic model establishment of secondary osteosarcoma: a SEER-based study

Background

Surgical excision is considered one of the most effective treatments for secondary osteosarcoma (SO). It remains unclear whether the survival of patients with secondary osteosarcoma (SO) could be associated with their surgical willingness.

Materials and methods

The statistics of the patients diagnosed with SO between 1975 and 2008 were gathered from the surveillance epidemiology and end results (SEER) database. The patients were divided into three subgroups according to their surgical compliance. The authors used the multivariable Logistic regression analysis and cox regression method to reveal the influence of surgical compliance on prognosis and the risk factors of surgical compliance. Additionally, the authors formulated a nomogram model to predict the overall survival (OS) of patients. The concordance index (C-index) was used to evaluate the accuracy and practicability of the above prediction model.

Results

Sixty-three (9.2%) of the 688 patients with SO who were recommended for surgical treatment refused to undergo surgery. Lower surgical compliance can be ascribed to an earlier time of diagnosis and refusal of chemotherapy. The lower overall survival (OS) {[hazard ratio (HR)] 1.733, [CI] 1.205-2.494, P value [P]=0.003} of not surgical compliant patients was verified by the multivariate cox regression method, compared with surgical compliant patients. In addition, the discernibility of the nomogram model was proven to be relatively high (C-index=0.748), by which we can calibrate 3-year- and 5-year OS prediction plots to obtain good concordance to the actual situation.

Conclusions

Surgical compliance was proved to be an independent prognostic factor in the survival of patients with SO.

Reduced recurrence rate and comparable functionality after wide resection and reverse total shoulder arthroplasty with allograft-prosthetic composite versus curettage for proximal humeral giant cell tumor: a multicenter retrospective study

BACKGROUND

Giant cell tumors of bone (GCTBs) are rare, aggressive tumors, and the proximal humerus is a relatively rare location for GCTBs; limited evidence exists on which surgical approaches and reconstruction techniques are optimal. In the largest case series to date, we evaluated the recurrence rate of proximal humeral GCTBs and the functional outcomes of different resection and reconstruction options in this multicenter study.

METHODS

All 51 patients included in this study received initial surgical treatment for proximal humeral GCTBs from January 2007 to December 2020, with a minimum 2-year follow-up period. Local recurrence and functional outcomes were statistically analyzed in relation to demographic, clinical, and primary surgical variables. Functional outcomes were reported by patients and were assessed by the Musculoskeletal Tumor Society score and QuickDASH instrument (shortened version of the Disabilities of the Arm, Shoulder and Hand instrument).

RESULTS

The mean follow-up period was 81.5 months (range, 30-191 months), and the overall recurrence rate was 17.6% (9 of 51 patients). The majority of recurrences (n = 7) occurred in the first 2 years of follow-up. The intralesional curettage group (n = 23) showed a statistically significant difference in the recurrence rate compared with the en bloc resection group (n = 28) (34.8% vs. 3.6%, P = .007). Among shoulders receiving en bloc resection, 16 were reconstructed with hemiarthroplasty; 8, reverse total shoulder arthroplasty (rTSA) with allograft-prosthetic composite (APC) reconstruction; and 4, arthrodesis. On the basis of intention-to-treat analysis, the mean functional Musculoskeletal Tumor Society scores of the groups undergoing curettage, rTSA with APC, hemiarthroplasty, and arthrodesis were 26.0 ± 3.1, 26.0 ± 1.7, 20.3 ± 2.8, and 22.5 ± 1.3, respectively (P < .001 [with P < .001 for curettage vs. hemiarthroplasty and P = .004 for rTSA with APC vs. hemiarthroplasty]) and the mean QuickDASH scores were 14.0 ± 11.0, 11.6 ± 4.5, 33.1 ± 11.8, and 21.6 ± 4.7, respectively (P < .001 [with P < .001 for curettage vs. hemiarthroplasty and P = .003 for rTSA with APC vs. hemiarthroplasty]).

CONCLUSIONS

On the basis of our data, en bloc resection followed by reverse shoulder arthroplasty showed a lower recurrence rate and no significant difference in functional outcome scores for proximal humeral GCTBs compared with intralesional curettage. Therefore, we believe that rTSA with APC may be reasonable for the initial treatment of proximal humeral GCTBs.

Chordoma cells possess bone-dissolving activity at the bone invasion front

PURPOSE

Chordomas are malignant tumors that destroy bones, compress surrounding nerve tissues and exhibit phenotypes that recapitulate notochordal differentiation in the axial skeleton. Chordomas recur frequently, as they resist radio-chemotherapy and are difficult to completely resect, leading to repeated bone destruction and local expansion via unknown mechanisms. Here, using chordoma specimens and JHC7 chordoma cells, we asked whether chordoma cells possess bone-dissolving activity.

METHODS

CT imaging and histological analysis were performed to evaluate the structure and mineral density of chordoma-invaded bone and osteolytic marker expression. JHC7 cells were subjected to immunocytochemistry, imaging of cell fusion, calcium dynamics and acidic vacuoles, and bone lysis assays.

RESULTS

In patients, we found that the skull base invaded by chordoma was highly porous, showed low mineral density and contained brachyury-positive chordoma cells and conventional osteoclasts both expressing the osteolytic markers tartrate-resistant acid phosphatase (TRAP) and collagenases. JHC7 cells expressed TRAP and cathepsin K, became multinucleated via cell-cell fusion, showed spontaneous calcium oscillation, and were partly responsive to the osteoclastogenic cytokine RANKL. JHC7 cells exhibited large acidic vacuoles, and nonregulatory bone degradation without forming actin rings. Finally, bone-derived factors, calcium ions, TGF-β1, and IGF-1 enhanced JHC7 cell proliferation.

CONCLUSION

In chordoma, we propose that in addition to conventional bone resorption by osteoclasts, chordoma cells possess bone-dissolving activity at the tumor-bone boundary. Furthermore, bone destruction and tumor expansion may occur in a positive feedback loop.

Desmoplastic fibroma in a child: a 9-year follow-up case report

BACKGROUND

Desmoplastic fibroma is an extremely rare primary bone tumor. Its characteristic features include bone destruction accompanied by the formation of soft tissue masses. This condition predominantly affects individuals under the age of 30. Since its histology is similar to desmoid-type fibromatosis, an accurate diagnosis before operation is difficult. Desmoplastic fibroma is resistant to chemotherapy, and the efficacy of radiotherapy is uncertain. Surgical excision is preferred for treatment, but it entails high recurrence. Further, skeletal reconstruction post-surgery is challenging, especially in pediatric cases.

CASE PRESENTATION

Nine years ago, a 14-year-old male patient presented with a 4-year history of progressive pain in his left wrist. Initially diagnosed as fibrous dysplasia by needle biopsy, the patient underwent tumor resection followed by free vascularized fibular proximal epiphyseal transfer for wrist reconstruction. However, a histological examination confirmed a diagnosis of desmoplastic fibroma. The patient achieved bone union and experienced a recurrence in the ipsilateral ulna 5 years later, accompanied by a wrist deformity. He underwent a second tumor resection and wrist arthrodesis in a single stage. The most recent annual follow-up was in September 2023; the patient had no recurrence and was satisfied with the surgery.

CONCLUSIONS

Desmoplastic fibroma is difficult to diagnose and treat, and reconstruction surgery after tumor resection is challenging. Close follow-up by experienced surgeons may be beneficial for prognosis.

Single-Cell RNA Sequencing Pro-angiogenic Macrophage Profiles Reveal Novel Prognostic Biomarkers and Therapeutic Targets for Osteosarcoma

Osteosarcoma (OS) is a malignant bone tumor that most commonly occurs in children and adolescents. OS patients have a poor prognosis, and 5-year survival rates have rarely improved significantly over the past few decades. OS prognosis may be related to the infiltration of tumor-associated macrophages (TAMs). However, the role of proangiogenic macrophages, a subtype of TAMs, in OS prognosis has not been reported. In this study, seven subtypes of TAMs were identified from single-cell RNA sequencing (scRNA-seq) data that we propose defining as proangiogenic TAMs (Angio-TAMs), interferon-primed TAMs (IFN-TAMs), inflammatory cytokine-enriched TAMs (Inflam-TAMs), immune regulatory TAMs (Reg-TAMs), lipid-associated TAMs (LA-TAMs), and resident-tissue macrophages like TAMs (RTM-TAMs) (containing two subcellular types). In the survival analysis of each macrophage subtype, it was found that patients with Angio-TAMs had the most significant difference in survival. Eight genes associated with Angio-TAMs were obtained by differential expression analysis, and these genes were built into a prognostic model using the LASSO algorithm. Clinical OS case samples were categorized into high-risk and low-risk subgroups using median risk scores. In comparison to the low-risk subgroup, the survival time of the high-risk subgroup was much shorter. Additional studies on immune cell infiltration and immune checkpoint molecule expression in the two risk subgroups were carried out. In immunotherapy response prediction, the Angio-TAM-associated gene risk signature was found to be negatively correlated with immune checkpoint responses. In addition, the associated enriched GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways were mainly involved in the malignant progression of tumors. As suggested by these findings, the Angio-TAM gene risk signature may be an underlying prognostic biomarker and novel therapeutic target for OS patients.Kindly check and confirm whether the ESM file is correctly identifiedWe have checked this file and confirmed that it can be correctly identified.

Incidence of skeletal-related events in patients with Ewing sarcoma: An observational retrospective study in Japan

BACKGROUND

Skeletal-related events (SREs), including the pathological fracture, surgical treatment or radiation of bone lesions, malignant spinal cord compression, hypercalcemia, are important considerations when managing metastatic bone tumors; however, owing to their rarity, the incidence of SREs in patients with Ewing sarcoma remains unknown.

METHODS

We retrospectively reviewed the clinical data from 146 patients with Ewing sarcoma treated at a single institution from 2005 to 2019. The median age at diagnosis was 22.7 years. Fifty patients (34.2%) had metastatic disease at diagnosis. The primary outcome was the SRE-free rate among patients with Ewing sarcoma. Moreover, we identified the risk factors for SREs using univariate or multivariate analyses.

RESULTS

During the observational period (median, 2.6 years), SREs occurred in 23 patients. Radiation to the bone, malignant spinal cord compression, and hypercalcemia were documented as the initial SREs in 12 patients (52.2%), 10 patients (43.5%), and one patient (4.3%), respectively. The SRE-free rate was 94.2 ± 2.0, 87.3 ± 3.0, and 79.6 ± 3.8% at 1, 2, and 3 years after the initial visit, respectively. Multivariate analysis revealed bone metastasis at diagnosis (hazard ratio [HR] = 4.41, p = 0.007), bone marrow invasion (HR = 34.08, p < 0.001), and local progression or recurrence after definitive treatment (HR = 3.98, p = 0.012) as independent risk factors for SREs.

CONCLUSIONS

SREs are non-rare events that can occur during the treatment course for Ewing sarcoma, with an especially high incidence of malignant spinal cord compression. Patients with metastatic disease at diagnosis, especially in the bone or bone marrow, or with local progression or recurrence after definitive treatment, should be carefully monitored for the occurrence of SREs. The most effective methods to monitor the occurrence of SREs and new preventative therapies for SREs should be investigated in the future.

Endosteal stem cells at the bone-blood interface: A double-edged sword for rapid bone formation: Bone marrow endosteal stem cells provide a robust source of bone-making osteoblasts both in normal and abnormal bone formation

Endosteal stem cells are a subclass of bone marrow skeletal stem cell populations that are particularly important for rapid bone formation occurring in growth and regeneration. These stem cells are strategically located near the bone surface in a specialized microenvironment of the endosteal niche. These stem cells are abundant in young stages but eventually depleted and replaced by other stem cell types residing in a non-endosteal perisinusoidal niche. Single-cell molecular profiling and in vivo cell lineage analyses play key roles in discovering endosteal stem cells. Importantly, endosteal stem cells can transform into bone tumor-making cells when deleterious mutations occur in tumor suppressor genes. The emerging hypothesis is that osteoblast-chondrocyte transitional identities confer a special subset of endosteal stromal cells with stem cell-like properties, which may make them susceptible for tumorigenic transformation. Endosteal stem cells are likely to represent an important therapeutic target of bone diseases caused by aberrant bone formation.

Bone tumors: state-of-the-art imaging

Imaging plays a central role in the management of patients with bone tumors. A number of imaging modalities are available, with different techniques having unique applications that render their use advantageous for various clinical purposes. Coupled with detailed clinical assessment, radiological imaging can assist clinicians in reaching a proper diagnosis, determining appropriate management, evaluating response to treatment, and monitoring for tumor recurrence. Although radiography is still the initial imaging test of choice for a patient presenting with a suspected bone tumor, technological innovations in the last decades have advanced the role of other imaging modalities for assessing bone tumors, including advances in computed tomography, magnetic resonance imaging, scintigraphy, and hybrid imaging techniques that combine two existing modalities, providing clinicians with diverse tools for bone tumor imaging applications. Determining the most suitable modality to use for a particular application requires familiarity with the modality in question, its advancements, and its limitations. This review highlights the various imaging techniques currently available and emphasizes the latest developments in imaging, offering a framework that can help guide the imaging of patients with bone tumors.

Evaluation of the Prognostic Value of Pretherapeutic Magnetic Resonance Imaging in Predicting Soft Tissue Sarcoma Radiation Response: A Retrospective Study from a Large Institutional Sarcoma Imaging Database

Background: RT-induced hyalinization/fibrosis was recently evidenced as a significant independent predictor for complete response to neoadjuvant radiotherapy (RT) and survival in patients with soft tissue sarcoma (STS). Purpose: Non-invasive predictive markers of histologic response after neoadjuvant RT of STS are expected. Materials and Methods: From May 2010 to April 2017, patients with a diagnosis of STS who underwent neoadjuvant RT for limb STS were retrieved from a single center prospective clinical imaging database. Tumor Apparent Diffusion Coefficients (ADC) and areas under the time-intensity perfusion curve (AUC) were compared with the histologic necrosis ratio, fibrosis, and cellularity in post-surgical specimens. Results: We retrieved 29 patients. The median ADC value was 134.3 × 10-3 mm2/s. ADC values positively correlated with the post-treatment tumor necrosis ratio (p = 0.013). Median ADC values were lower in patients with less than 50% necrosis and higher in those with more than 50% (120.3 × 10-3 mm2/s and 202.0 × 10-3 mm2/s, respectively (p = 0.020). ADC values higher than 161 × 10-3 mm2/s presented a 95% sensitivity and a 55% specificity for the identification of tumors with more than 50% tumor necrosis ratio. Tumor-to-muscle AUC ratios were associated with histologic fibrosis (p = 0.036). Conclusions: ADC and perfusion AUC correlated, respectively, with radiation-induced tumor necrosis and fibrosis.

Prevalence of TERT Promoter Mutations in Orbital Solitary Fibrous Tumors

The orbital manifestation of a solitary fibrous tumor (SFT) is exceptionally rare and poses specific challenges in diagnosis and treatment. Its rather exceptional behavior among all SFTs comprises a high tendency towards local recurrence, but it rarely culminates in metastatic disease. This raises the question of prognostic factors in orbital SFTs (oSFTs). Telomerase reverse transcriptase (TERT)-promoter mutations have previously been linked to an unfavorable prognosis in SFTs of other locations. We analyzed the prevalence of TERT promoter mutations of SFTs in the orbital compartment. We performed a retrospective, descriptive clinico-histopathological analysis of nine cases of oSFTs between the years of 2017 and 2021. A TERT promoter mutation was present in one case, which was classified with intermediate metastatic risk. Local recurrence or progress occurred in six cases after primary resection; no distant metastases were reported. Multimodal imaging repeatedly showed particular morphologic patterns, including tubular vascular structures and ADC reduction. The prevalence of the TERT promoter mutation in oSFT was 11%, which is similar to the prevalence of extra-meningeal SFTs of the head and neck and lower than that in other extra-meningeal compartments. In the present study, the TERT promoter mutation in oSFT manifested in a case with an unfavorable prognosis, comprising aggressive local tumor growth, local recurrence, and eye loss.

A 30-year bibliometric analysis of the literature in the disciplines of orthopedics, surgery, or oncology on chondrosarcoma from 1993 to 2023

BACKGROUND

A thorough bibliometric analysis of publications published in the field of chondrosarcoma research has not yet been performed using the Web of Science database, especially for publications published between 1993 and 2023. This study, with a focus on the fields of orthopedics, surgery, and oncology, aims to fill this knowledge gap by providing a thorough analysis of current knowledge in the field of chondrosarcoma.

METHODS

In this bibliometric study, a literature search was performed using the Web of Science database to find all publications on chondrosarcoma. A bibliometric software program was used for data visualization and analysis (opensource visualization application, Vosviewer). The Web of Science Core Collection data used for this retrospective bibliometric study, which covers the period from January 1993 to September 2023, revealed interesting trends in chondrosarcoma research.

RESULTS

As the most popular fields of study, orthopedics, surgery, and oncology account for a sizable portion of publications. A noteworthy increase in research output from 2014 to 2023, accounting for 41.74% of the papers, reflects the thriving research environment. The leading countries for publication were China, Japan, and the United States, demonstrating cross-border cooperation in chondrosarcoma research. Their contributions were highlighted by their important affiliations with institutions such as Harvard University, Leiden University, and China Medical University Taiwan. A thorough keyword mapping analysis also highlighted research priorities and encouraged interdisciplinary cooperation. The field's scholarly importance and ongoing relevance are highlighted by the study's high citation count (30,076) and highly cited articles.

CONCLUSION

Overall, this study offers crucial insights into the development and collaborative nature of the chondrosarcoma research landscape and its long-lasting influence on academic research and clinical practice.

Deep learning for differentiation of osteolytic osteosarcoma and giant cell tumor around the knee joint on radiographs: a multicenter study

OBJECTIVES

To develop a deep learning (DL) model for differentiating between osteolytic osteosarcoma (OS) and giant cell tumor (GCT) on radiographs.

METHODS

Patients with osteolytic OS and GCT proven by postoperative pathology were retrospectively recruited from four centers (center A, training and internal testing; centers B, C, and D, external testing). Sixteen radiologists with different experiences in musculoskeletal imaging diagnosis were divided into three groups and participated with or without the DL model's assistance. DL model was generated using EfficientNet-B6 architecture, and the clinical model was trained using clinical variables. The performance of various models was compared using McNemar's test.

RESULTS

Three hundred thirty-three patients were included (mean age, 27 years ± 12 [SD]; 186 men). Compared to the clinical model, the DL model achieved a higher area under the curve (AUC) in both the internal (0.97 vs. 0.77, p = 0.008) and external test set (0.97 vs. 0.64, p < 0.001). In the total test set (including the internal and external test sets), the DL model achieved higher accuracy than the junior expert committee (93.1% vs. 72.4%; p < 0.001) and was comparable to the intermediate and senior expert committee (93.1% vs. 88.8%, p = 0.25; 87.1%, p = 0.35). With DL model assistance, the accuracy of the junior expert committee was improved from 72.4% to 91.4% (p = 0.051).

CONCLUSION

The DL model accurately distinguished osteolytic OS and GCT with better performance than the junior radiologists, whose own diagnostic performances were significantly improved with the aid of the model, indicating the potential for the differential diagnosis of the two bone tumors on radiographs.

CRITICAL RELEVANCE STATEMENT

The deep learning model can accurately distinguish osteolytic osteosarcoma and giant cell tumor on radiographs, which may help radiologists improve the diagnostic accuracy of two types of tumors.

KEY POINTS

• The DL model shows robust performance in distinguishing osteolytic osteosarcoma and giant cell tumor. • The diagnosis performance of the DL model is better than junior radiologists'. • The DL model shows potential for differentiating osteolytic osteosarcoma and giant cell tumor.

Tracked ultrasound registration for intraoperative navigation during pediatric bone tumor resections with soft tissue components: a porcine cadaver study

PURPOSE

Resection of pediatric osteosarcoma in the extremities with soft tissue involvement presents surgical challenges due to difficult visualization and palpation of the tumor. Therefore, an adequate image-guided surgery (IGS) system is required for more accurate tumor resection. The use of a 3D model in combination with intraoperative tracked ultrasound (iUS) may enhance surgical decision making. This study evaluates the clinical feasibility of iUS as a surgical tool using a porcine cadaver model.

METHODS

First, a 3D model of the porcine lower limb was created based on preoperative scans. Second, the bone surface of the tibia was automatically detected with an iUS by a sweep on the skin. The bone surface of the preoperative 3D model was then matched with the bone surface detected by the iUS. Ten artificial targets were used to calculate the target registration error (TRE). Intraoperative performance of iUS IGS was evaluated by six pediatric surgeons and two pediatric oncologic orthopedists. Finally, user experience was assessed with a post-procedural questionnaire.

RESULTS

Eight registration procedures were performed with a mean TRE of 6.78 ± 1.33 mm. The surgeons agreed about the willingness for clinical implementation in their current clinical practice. They mentioned the additional clinical value of iUS in combination with the 3D model for the localization of the soft tissue components of the tumor. The concept of the proposed IGS system is considered feasible by the clinical panel, but the large TRE and degree of automation need to be addressed in further work.

CONCLUSION

The participating pediatric surgeons and orthopedists were convinced of the clinical value of the interaction between the iUS and the 3D model. Further research is required to improve the surgical accuracy and degree of automation of iUS-based registration systems for the surgical management of pediatric osteosarcoma.

Diagnostics of IDH1/2 Mutations in Intracranial Chondroid Tumors: Comparison of Molecular Genetic Methods and Immunohistochemistry

Intracranial chondroid tumors are a heterogeneous group of neoplasms characterized by the presence of a cartilage matrix. These tumors exhibit overlapping clinical and histological features. Mutations in IDH1/2 genes serve as important diagnostic markers of tumor type, particularly chondrosarcoma. To improve the accuracy of IDH1/2 diagnostics, we compared three methods: biochip assay, real-time PCR with DNA melting analysis using TaqMan probes and sequencing (qPCR-DMA-Sanger), and immunohistochemistry (IHC). Tumor samples from 96 patients were investigated. The IDH1 mutations were detected in 34/64 (53%) chondrosarcomas; IHC detected 27/56 (48.2%) mutations, the qPCR-DMA-Sanger method 27/59 (46%) mutations, and the biochip assay revealed 29/60 (48.3%) mutations. The detection of IDH1 mutations in chordoma (2/15) and osteosarcoma (2/7) suggested the need for a revised diagnosis. In benign tumors, IDH1 mutations were present in chondroma (4/6), but absent in chondromyxoid fibroma (0/4). The most frequent IDH1 mutations were R132C (60%), R132L, and R132G (13.5% each), R132H (8%), and R132S (5%). The concordance between the biochip assay and IHC was 90%, between IHC and PCR-DMA-Sanger 83%, and between biochip assay and qPCR-DMA-Sanger was 98%, respectively. No IDH2 mutations were found. The use of independent diagnostic methods may improve the detection of IDH-mutant specimens in chondroid tumors.

Twenty-year outcome of prevalence, incidence, mortality and survival rate in patients with malignant bone tumors

Malignant bone tumors are a group of rare malignant tumors and our study aimed to update the recent epidemiologic estimates based on the Surveillance, Epidemiology and End Results database. Patients diagnosed with malignant bone tumors from 2000 to 2019 were included and their characteristics were retrospectively described. The limited-duration prevalence, annual age-adjusted incidence and mortality were calculated, and the annual percentage changes were analyzed to quantify the rate change. Finally, observed survival and relative survival rate were illustrated. Subgroup analysis across tumor type, age, gender, tumor Grade, primary tumor site and stage was also performed. As for results, a total of 11 655 eligible patients with malignant bone tumor were selected. Osteosarcoma was the most common tumor type, followed by chondrosarcoma, Ewing sarcoma and chordoma. The estimated limited-duration prevalence of malignant bone tumors increased from 2000 (0.00069%) to 2018 (0.00749%). Steady age-adjusted incidence was observed in all patients during the study period while the highest rate occurred in osteosarcoma. Mortality rates differed in subgroups while elder patients (older than 64 years) presented the highest mortality rate compared to other age groups. In all bone tumors, the 10-year observed survival and relative survival rates were 58.0% and 61.9%, respectively. Chondrosarcoma patients had the best survival outcome, followed by osteosarcoma, Ewing sarcoma, chordoma and other bone tumors. In conclusion, different epidemiologic performance in incidence and mortality was observed across tumor type as well as other demographic and clinicopathological variables, which provide potential suggestion for further adjustment of medical resource.

Update of cartilaginous tumours according to the WHO classification 2020

Cartilaginous tumours are a large and heterogeneous group of neoplasms characterised by the presence of a chondroid matrix, with lobular growth and arcuate, ring-like or popcorn-like calcification patterns. MRI shows hyperintensity in T2-weighted sequences and a lobulated or septal relief in postcontrast images. In the WHO 2020 classification, chondral tumours are classified as benign, intermediate or malignant. Despite technological advances, they continue to pose a challenge for both the radiologist and the pathologist, being the main difficulty the differentiation between benign and malignant tumours, which is why they require a multidisciplinary approach. This paper describes the main changes introduced in the 2020 update, describes the imaging characteristics of the main cartilaginous tumours and provides the radiological keys to differentiate between benign and malignant tumours.

The coenzyme A precursor pantethine enhances antitumor immunity in sarcoma

The tumor microenvironment is a dynamic network of stromal, cancer, and immune cells that interact and compete for resources. We have previously identified the Vanin1 pathway as a tumor suppressor of sarcoma development via vitamin B5 and coenzyme A regeneration. Using an aggressive sarcoma cell line that lacks Vnn1 expression, we showed that the administration of pantethine, a vitamin B5 precursor, attenuates tumor growth in immunocompetent but not nude mice. Pantethine boosts antitumor immunity, including the polarization of myeloid and dendritic cells towards enhanced IFNγ-driven antigen presentation pathways and improved the development of hypermetabolic effector CD8+ T cells endowed with potential antitumor activity. At later stages of treatment, the effect of pantethine was limited by the development of immune cell exhaustion. Nevertheless, its activity was comparable with that of anti-PD1 treatment in sensitive tumors. In humans, VNN1 expression correlates with improved survival and immune cell infiltration in soft-tissue sarcomas, but not in osteosarcomas. Pantethine could be a potential therapeutic immunoadjuvant for the development of antitumor immunity.

The expression changes of PD-L1 and immune response mediators are related to the severity of primary bone tumors

The expression pattern, diagnostic value, and association of PD-L1, IFN-γ and TGF-β with bone tumor type, severity, and relapse are determined in this study. 300 human samples from patients with osteosarcoma, Ewing sarcoma, and GCT were enrolled. The PD-L1 gene and protein expression were assessed by qRT-PCR and immunohistochemistry, respectively. ELISA and flow cytometry was used to detect cytokines and CD4/CD8 T cell percentages, respectively. A considerable increase in PD-L1 level was detected in bone tumor tissues at both gene and protein levels that was considerable in osteosarcoma and Ewing sarcoma. A positive correlation was detected regarding the PD-L1 and tumor metastasis and recurrence in osteosarcoma and Ewing sarcoma. The increased IFN-γ level was detected in patients with metastatic, and recurrent osteosarcoma tumors that were in accordance with the level of TGF-β in these samples. The simultaneous elevation of IFN-γ and TGF-β was detected in Ewing sarcoma and GCT, also the CD4 + /CD8 + ratio was decreased significantly in patients with osteosarcoma compared to GCT tumors. The elevated levels of PD-L1, TGF- β, and IFN-γ were associated with bone tumor severity that can provide insights into the possible role of this axis in promoting immune system escape, suppression, and tumor invasion.

PROTAC-Based Protein Degradation as a Promising Strategy for Targeted Therapy in Sarcomas

Sarcomas are heterogeneous bone and soft tissue cancers representing the second most common tumor type in children and adolescents. Histology and genetic profiling discovered more than 100 subtypes, which are characterized by peculiar molecular vulnerabilities. However, limited therapeutic options exist beyond standard therapy and clinical benefits from targeted therapies were observed only in a minority of patients with sarcomas. The rarity of these tumors, paucity of actionable mutations, and limitations in the chemical composition of current targeted therapies hindered the use of these approaches in sarcomas. Targeted protein degradation (TPD) is an innovative pharmacological modality to directly alter protein abundance with promising clinical potential in cancer, even for undruggable proteins. TPD is based on the use of small molecules called degraders or proteolysis-targeting chimeras (PROTACs), which trigger ubiquitin-dependent degradation of protein of interest. In this review, we will discuss major features of PROTAC and PROTAC-derived genetic systems for target validation and cancer treatment and focus on the potential of these approaches to overcome major issues connected to targeted therapies in sarcomas, including drug resistance, target specificity, and undruggable targets. A deeper understanding of these strategies might provide new fuel to drive molecular and personalized medicine to sarcomas.

Rheumatoid arthritis increases the risk of malignant neoplasm of bone and articular cartilage: a two-sample bidirectional mendelian randomization study

OBJECTIVE

Prior research has revealed a heightened prevalence of neoplasms in individuals diagnosed with rheumatoid arthritis (RA). The primary objective of this study is to delve into the causal association between RA and two distinct types of neoplasms: benign neoplasm of bone and articular cartilage (BNBAC) and malignant neoplasm of bone and articular cartilage (MNBAC).

METHODS

We employed summary data from genome-wide association analyses (GWAS) to investigate the causal relationship between RA and two neoplasms, BNBAC and MNBAC, using a two-sample bidirectional Mendelian randomization (MR) study design. The IEU OpenGWAS database provided the GWAS summary data for RA, while the Finnish consortium supplied the GWAS summary data for BNBAC and MNBAC. Our analysis involved the utilization of eight distinct MR methods, namely random-effects inverse variance weighted (IVW), MR Egger, weighted median, simple mode, weighted mode, maximum likelihood, penalized weighted median, and fixed effects IVW. Subsequently, we conducted assessments to evaluate heterogeneity, horizontal pleiotropy, outliers, the impact of a single-nucleotide polymorphism (SNP), and adherence to the assumption of normal distribution in the MR analysis.

RESULTS

The results from the MR analysis revealed that there was no significant genetic association between RA and BNBAC (P = 0.427, odds ratio [OR] 95% confidence interval [CI] = 0.971 [0.904-1.044]). However, a positive genetic association was observed between RA and MNBAC (P = 0.001, OR 95% CI = 1.413 [1.144-1.745]). Conducting a reverse MR analysis, we found no evidence to support a genetic causality between BNBAC (P = 0.088, OR 95% CI = 1.041 [0.994-1.091]) or MNBAC (P = 0.168, OR 95% CI = 1.013 [0.995-1.031]) and RA. Our MR analysis demonstrated the absence of heterogeneity, horizontal pleiotropy, and outliers and confirmed that the effect was not driven by a single SNP. Additionally, the data exhibited a normal distribution.

CONCLUSION

The findings of this study demonstrate that RA constitutes a significant risk factor for MNBAC. In the context of clinical application, it is advisable to conduct MNBAC screening in RA patients and remain vigilant regarding its potential manifestation. Importantly, the outcomes of this investigation introduce a fresh vantage point into the understanding of the tumorigenesis associated with RA.

Benign Bone Tumors Beyond Osteoid Osteoma: Percutaneous Minimally Invasive Image-Guided Interventions

Painful benign bone tumors often adversely influence quality of life primarily due to skeletal-related events such as unremittable pain, pathologic fracture, neurologic deficit, as well as skeletal growth disturbance. Substantial advances in percutaneous minimally invasive interventions for treatment of painful benign bone tumors beyond osteoid osteoma have been established as safe, efficacious, and durable treatments to achieve definitive cure. This article details the available armamentarium and most recent advances in minimally invasive percutaneous interventions and the role of radiologists for the management of patients with benign bone tumors beyond osteoid osteoma.

Integrative analysis of TROAP with molecular features, carcinogenesis, and related immune and pharmacogenomic characteristics in soft tissue sarcoma

Soft tissue sarcoma (STS) is an uncommon malignancy that often carries a grim prognosis. Trophinin-associated protein (TROAP) is augmented in a variety of tumors and can affect tumor proliferation. Nevertheless, the prognostic value and specific functions of TROAP in STS are still vague. Herein, we display that TROAP exhibits an augmented trend in STS, and its elevation correlates with a poor prognosis of STS. Furthermore, its reduction is related to increased immune cell infiltration, enhanced stroma, and elevation of immune activation. Meanwhile, the TROAP-derived genomic signature is validated to predict patient prognosis, immunotherapy, and drug response reliably. A nomogram constructed based on age, metastatic status, and a TROAP-derived risk score of an STS individual could be used to quantify the survival probability of STS. In addition, in vitro experiments have demonstrated that TROAP is overexpressed in STS, and the downregulation of TROAP could affect the proliferation, migration, metastasis, and cell cycle of STS cells. In summary, the TROAP expression is elevated in STS tissues and cells, which is related to the poor prognosis and malignant biological behaviors of STS. It could act as a potential prognostic biomarker for diagnosis and treatment of STS.

Artificial intelligence-based radiomics in bone tumors: Technical advances and clinical application

Radiomics is the extraction of predefined mathematic features from medical images for predicting variables of clinical interest. Recent research has demonstrated that radiomics can be processed by artificial intelligence algorithms to reveal complex patterns and trends for diagnosis, and prediction of prognosis and response to treatment modalities in various types of cancer. Artificial intelligence tools can utilize radiological images to solve next-generation issues in clinical decision making. Bone tumors can be classified as primary and secondary (metastatic) tumors. Osteosarcoma, Ewing sarcoma, and chondrosarcoma are the dominating primary tumors of bone. The development of bone tumor model systems and relevant research, and the assessment of novel treatment methods are ongoing to improve clinical outcomes, notably for patients with metastases. Artificial intelligence and radiomics have been utilized in almost full spectrum of clinical care of bone tumors. Radiomics models have achieved excellent performance in the diagnosis and grading of bone tumors. Furthermore, the models enable to predict overall survival, metastases, and recurrence. Radiomics features have exhibited promise in assisting therapeutic planning and evaluation, especially neoadjuvant chemotherapy. This review provides an overview of the evolution and opportunities for artificial intelligence in imaging, with a focus on hand-crafted features and deep learning-based radiomics approaches. We summarize the current application of artificial intelligence-based radiomics both in primary and metastatic bone tumors, and discuss the limitations and future opportunities of artificial intelligence-based radiomics in this field. In the era of personalized medicine, our in-depth understanding of emerging artificial intelligence-based radiomics approaches will bring innovative solutions to bone tumors and achieve clinical application.

Giant cell tumors of the distal ulna: long-term recurrence rate and functional outcomes of en bloc resection versus curettage in a multicenter study

OBJECTIVE

The wrist is the second most commonly involved location for GCTB, while distal ulna is a relatively rare location and limited evidence exists on which surgical approaches and reconstruction techniques are optimal. We carried out a multicenter retrospective study to evaluate the recurrence rate of distal ulna GCTB and the long-term functional outcomes of different surgery options.

METHODS

All 28 patients received surgical treatment for distal ulna GCTB in one of three tertiary bone tumor centers between May 2007 and January 2021 with a minimum two-year follow-up. Surgical options included intralesional curettage or en bloc resection (one of 3 types). Functional outcomes were assessed by the MSTS score, the QuickDASH instrument, MWS, and MHQ according to the latest treatment.

RESULTS

Overall recurrence rate was 14.2%. The curettage group (N = 7) had a significantly higher recurrence rate compared to en bloc resection (N = 21) (42.9% vs 4.8%) (mean follow-up: 88.8 mo). Seven patients received the Darrach procedure, 5 received the original Sauvé-Kapandji procedure, and 9 received the modified Sauvé-Kapandji procedure with extensor carpi ulnaris (ECU) tenodesis. Of the 4 patients having a recurrence, 1 received the Darrach EBR, 2 received the modified Sauvé-Kapandji procedure, and 1 received resection for soft tissue recurrence. Only MWS and esthetics in the MHQ scores were different (curettage, Darrach, Sauvé-Kapandji, and Sauvé-Kapandji with ECU tenodesis [MWS: 96.5 ± 1.3 vs 91.5 ± 4.7 vs 90.8 ± 2.8 vs 91.5 ± 3.6; esthetics in MHQ: 98.5 ± 3.1 vs 89.9 ± 4.7 vs 93.8 ± 4.4 vs 92.6 ± 3.8], respectively).

CONCLUSIONS

En bloc resection for distal ulna GCTB had a significantly lower recurrence rate compared with curettage and achieved favorable functional outcome scores. Given the higher recurrence rate after curettage, patients should be well informed of the potential benefits and risks of selecting the distal radioulnar joint-preserving procedure. Moreover, reconstructions after tumor resection of the ulna head do not appear to be necessary.

A novel TPD52L2-ROS1 gene fusion expanding the molecular alterations in inflammatory myofibroblastic tumor: case report and literature review

BACKGROUND

Inflammatory myofibroblastic tumor (IMT) is a distinctive tumor composed of spindle cells accompanied by mixed inflammatory cells, and immunohistochemical positivity for ALK (anaplastic lymphoma kinase protein) can be detected in half of IMTs. The diagnosis of ALK-negative IMT could be a challenge. Recently, the fusions of some kinase genes, such as RET, NTRK1, ROS1, etc., are revealed in ALK-negative IMT.

CASE PRESENTATION

A 19-year-old woman presented with swelling of the left upper arm. Magnetic resonance imaging (MRI) scan revealed a tumor in the left postbrachium extended to the left axillary, serratus anterior muscle, and latissimus dorsi muscle. Histopathologically, the irregular-circumscribed tumor was composed of dense spindle-shaped cells with eosinophilic abundant cytoplasm and hyalinized mesenchyme in an inflammatory background. Immunohistochemically (IHC), tumor cells were positive for SMA, MDM2, and p16; the cells were negative for desmin, MyoD1, Myogenin, pan-cytokeratin, S100, SOX10, HMB45, Malen-A, CD34, CD31, CD99, and ALK. By RNA-based NGS, a novel fusion between TPD52L2 3' end of exon 1-4 and ROS1 5' end of exon 36-43 was revealed. ROS1 IHC staining was negative. The final diagnosis of IMT with TPD52L2-ROS1 fusion was made. Subsequently, the patient experienced a good clinical response to Crizotinib, and clinical follow-up showed stable disease after 9 months.

CONCLUSION

This report expands the spectrum of ROS1 gene rearrangements in the IMT and highlights the importance of molecular analysis of IMT for getting a diagnostic clue and determining potential therapeutic strategies.

Surgery for fibrous dysplasia associated with aneurysmal-bone-cyst-like changes in right proximal femur: A case report

BACKGROUND

Fibrous dysplasia associated with aneurysmal bone cyst (ABC)-like changes in the right proximal femur has a low incidence. It is considered more difficult to make early diagnosis than for single fibrous dysplasia.

CASE SUMMARY

A 14-year-old woman was admitted because of persistent pain in the right hip and abnormal gait over the previous 2 mo. She had no history of present or past illness. Preoperative photography, enhanced computed tomography, and magnetic resonance imaging showed ground-glass appearance with cortical scalloping and expansion of the right proximal femur and femoral neck. Pathological examination by preoperative puncture biopsy revealed fibrous dysplasia of the right proximal femur. The patient was diagnosed with fibrous dysplasia based on medical history, physical examination, and results of laboratory, imaging and pathological examinations. According to final pathological examination, the patient was diagnosed with fibrous dysplasia of the right proximal femur associated with ABC. Curettage and allograft along with fixation of compression screws was performed for fibrous dysplasia associated with ABC-like changes. No obvious allograft absorption, loosening of fixation, or secondary fracture were observed during 6-months' follow-up with re-examination by plain radiography and computed tomography. Fibrous dysplasia associated with ABC-like changes in the right proximal femur has a low incidence and early diagnosis is considered more difficult than for single fibrous dysplasia.

CONCLUSION

We report a cases of fibrous dysplasia associated with ABC-like changes in the right proximal femur treated with curettage and allograft along with hip compression screws.

Extraskeletal myxoid chondrosarcoma of the gingival: a rare case report and review of the literature

BACKGROUND

Extraskeletal myxoid chondrosarcoma (EMC) is a rare malignant tumor described in the head and neck region, especially in the gingival. We present one case arising in the gingival of right mandible, and briefly reviewed the related literature.

CASE PRESENTATION

A 24-year-old male patient with a lesion of 3.5*2.0 cm in buccal gingival of right posterior mandible for 2 months. The tumor was composed of cartilaginous structures and myxoid matrix. Immunohistochemical(IHC) showed that the tumor cells to be positive for vimentin, focally positive for S-100, negative for calponin, SMA, SOX10. The Ki-67 labelling index was 80%. Fluorescent in situ Hybridization (FISH) was positive for NR4A3 rearrangement.

CONCLUSIONS

Due to its unusual site and low incidence in the oral region, a combination of histological findings, immunohistochemistry, and molecular pathology as well as differential diagnosis with other diseases should be taken into consideration in the process of clinical diagnosis and treatment.

A multicenter retrospective analysis of clinical outcomes of intracranial chondrosarcoma in 26 patients

Intracranial chondrosarcoma is a rare tumor with limited reports. We reviewed the clinical outcomes, imaging findings, and pathological characteristics at three centers to improve the diagnosis and treatment of intracranial chondrosarcoma. We retrospectively analyzed 26 patients with intracranial chondrosarcoma who had undergone surgical treatment at Tangdu Hospital of Air Force Military Medical University, Mianyang Central Hospital, and Nanchong Central Hospital from January 2010 to July 2022. Clinical manifestations, imaging features, surgical treatment, prognosis, and overall survival (OS) were analyzed. All 26 chondrosarcomas were located at the skull base. Gross total resection (GTR), subtotal resection (STR), and partial resection (PR) were performed in 14, 10, and 2 cases, respectively. Four cases underwent endoscopic transnasal surgery, while the remaining cases underwent craniotomy. The clinical symptoms were evaluated 1 week after surgery, and 15 cases were relieved to varying degrees. Postoperative complications included pulmonary infection, subcutaneous hydrops, dysphagia and choking, facial numbness, abducens paralysis, and intracranial infection (ICI). Fifteen cases received postoperative adjuvant radiotherapy. Seven cases showed recurrence: two with PR, four with STR, and one with GTR. Six cases received reoperation or radiotherapy after tumor progression, and one untreated patient died 5 months after tumor recurrence. The extent of tumor resection (HR 21.74, 95% CI 1.25-376.6, P = 0.03) and pathological grading (HR 131.99, 95% CI 4.05-4300.5, P = 0.006) were associated with improved OS. We presented our experience in the treatment of intracranial chondrosarcoma at three centers in the past 12 years. Intracranial chondrosarcoma lacked typical imaging features and are difficult to differentiate from other skull base lesions. Maximum extent of tumor resection with minimal injury to neurological function remains the most important treatment strategy. The extent of surgical resection and pathological grading were found to be predictors for OS.

Surgery and proton radiation therapy for pediatric base of skull chordomas: Long-term clinical outcomes for 204 patients

BACKGROUND

Data on clinical outcomes for base of skull (BOS) chordomas in the pediatric population is limited. We report patient outcomes after surgery and proton radiotherapy (PRT).

METHODS

Pediatric patients with BOS chordomas were treated with PRT or combined proton/photon approach (proton-based; for most, 80% proton/20% photon) at the Massachusetts General Hospital from 1981 to 2021. Endpoints of interest were overall survival (OS), disease-specific survival, progression-free survival (PFS), freedom from local recurrence (LC), and freedom from distant failure (DC).

RESULTS

Of 204 patients, median age at diagnosis was 11.1 years (range, 1-21). Chordoma location included 59% upper and/or middle clivus, 36% lower clivus, 4% craniocervical junction, and 1% nasal cavity. Fifteen (7%) received pre-RT chemotherapy. Forty-seven (23%) received PRT, and 157 (77%) received comboRT. Median total dose was 76.7 Gy (RBE) (range, 59.3-83.3). At a median follow-up of 10 years (interquartile range, 5-16 years), 56 recurred. Median OS and PFS were 26 and 25 years, with 5-, 10-, and 20-year OS and PFS rates of 84% and 74%, 78% and 69%, and 64% and 64%, respectively. Multivariable actuarial analyses showed poorly differentiated subtype, radiographical progression prior to RT, larger treatment volume, and lower clivus location to be prognostic factors for worse OS, PFS, and LC. RT was well tolerated at a median follow-up of 9 years (interquartile range, 4-16 years). Side effects included 166 patients (80%) with mild/moderate acute toxicities, 24 (12%) patients with late toxicities, and 4 (2%) who developed secondary radiation-related malignancies.

CONCLUSION

This is the largest cohort of BOS chordomas in the literature, pediatric and/or adult. High-dose PRT following surgical resection is effective with low rates of late toxicity.

Clinical significance of adjuvant therapy after radical surgery for primary osteosarcoma of the jaws

BACKGROUND

Osteosarcoma of the jaw is one of the rare malignancies and the role of postoperative adjuvant therapy is unclear. This study explored the efficacy of adjuvant therapy after radical surgery for primary osteosarcoma of the jaw.

METHODS

The data were retrospectively analyzed from May 2012 to June 2021. The recurrence rate, disease-free survival (DFS) and 5‑year overall survival (OS) rate were calculated by Kaplan-Meier method. Intergroup rates were examined by chi-square test.

RESULTS

125 post-radical surgery patients were included. The median follow-up time was 66 months. Forty five cases suffered recurrence. The recurrence rate was 36.0%, and the 5‑year OS rate was 68.8%. In the adjuvant treatment group, twenty eight of 99 patients experienced disease progression. In the surgical treatment alone group, seventeen of 26 patients experienced disease progression. The recurrence rates in the two groups were 28.3 and 65.4%, respectively (χ2 = 12.303, p < 0.001). The 5‑year OS rate was 75.8 and 42.3%, respectively (χ2 = 10.734, p = 0.001). The median DFS of the relapse patients was 15.1 months (95% CI:13.00-17.20 months), and the 5‑year OS rate was 40.0%. Among them, 28 patients received adjuvant therapy while 17 received surgical treatment alone. The median DFS was 15.7 and 11.5 months, respectively, p = 0.024. The median OS was 69.6 months (95% CI 55.69 ~ 83.51 months) and 62.4 months (95% CI 49.06 ~ 75.74 months), respectively(p = 0.034).

CONCLUSION

Adjuvant therapy is one of the effective measures to reduce the relapse rate and improve OS after radical surgery for primary osteosarcoma of the jaw.

Natural history of intraosseous low-grade chondroid lesions of the proximal humerus

Introduction

Enchondromas and grade 1 chondrosarcomas are commonly encountered low-grade chondroid tumors in the proximal humerus. While there is a concern for malignant transformation, few studies have evaluated the natural history of these lesions. The purpose of this study is to evaluate the natural history of proximal humerus low-grade chondroid lesions managed both conservatively and surgically, and to define management criteria using clinical and radiographic findings for these low-grade chondroid lesions.

Methods

The patient population included 90 patients intended for conservative treatment and 22 patients proceeding directly to surgery. Data collection was based on a combination of chart review and patient imaging and descriptive statistics were calculated for each group.

Results

No malignant transformations were noted amongst any group. In the conservative treatment group, 7 of 64 (11%) progressed to surgery after an average of 20.3 months of conservative treatment due to persistent pain unexplained by other shoulder pathology. Importantly, 71% experienced continued pain at a mean of 53.1 months post-operatively. The group that went directly to surgery also demonstrated pain in 41% at an average follow-up of 57.3 months.

Discussion

Low-grade cartilaginous lesions of the proximal humerus without concerning imaging findings can be managed with conservative treatment and the risk of malignant transformation is very low. Patients with a clear source of their shoulder pain unrelated to their tumor and without concerning characteristics on imaging can be managed with serial annual radiographic imaging. Patients undergoing surgery for these indolent tumors are likely to experience persistent pain even after surgery.

The clinical significance of CD44v6 in malignant and benign primary bone tumors

BACKGROUND

The objective of this study was to assess the expression profile of CD44v6, a potential cancer stem cell marker, and its diagnostic and predictive significance in three distinct types of primary bone tumors.

METHODS

In this study, we utilized real-time qRT-PCR and immunohistochemistry to examine the gene and protein levels of CD44v6 in a total of 138 fresh bone tissues. This included 69 tumor tissues comprising osteosarcoma (N = 23), chondrosarcoma (N = 23), and GCT (N = 23), as well as 69 corresponding non-cancerous tumor margins. Furthermore, we investigated the circulating level of CD44v6 by isolating peripheral blood mononuclear cells from 92 blood samples. Among these, 69 samples were obtained from patients diagnosed with primary bone tumors, while the remaining 23 samples were from healthy donors. The primary objectives of our investigation were to assess the correlation between CD44v6 expression levels and clinic-pathological features of the patients, as well as to evaluate the diagnostic and predictive values of CD44v6 in this context.

RESULTS

In patients with osteosarcoma and chondrosarcoma tumors, both the gene and protein expression of CD44v6 were found to be significantly higher compared to the GCT group. Furthermore, the circulating level of CD44v6 was notably elevated in patients diagnosed with osteosarcoma and chondrosarcoma in comparison to the GCT group and patients with malignant tumor characteristics. Additionally, we observed a strong correlation between the gene and protein levels of CD44v6 and important tumor indicators such as tumor grade, metastasis, recurrence, and size at the tumor site. CD44v6 shows potential in differentiating patients with bone tumors from both control groups and tumor groups with severe and invasive characteristics from those with non-severe features. Importantly, the expression level of CD44v6 also demonstrated predictive value for determining tumor grade and the likelihood of recurrence.

CONCLUSION

CD44v6 is likely to play a role in the development of primary bone tumors and has the potential to serve as a diagnostic biomarker for bone cancer. However, to obtain more accurate and conclusive findings, further mechanistic investigations involving larger population samples are necessary.

Case Report: Non-ossifying fibromas with pathologic fractures in a patient with NONO-associated X-linked syndromic intellectual developmental disorder

The NONO gene encodes a nuclear protein involved in transcriptional regulation, RNA synthesis and DNA repair. Hemizygous loss-of function, de novo or maternally inherited variants in NONO have been associated with an X-linked syndromic intellectual developmental disorder-34 (OMIM # 300967), characterized by developmental delay, intellectual disability, hypotonia, macrocephaly, elongated face, structural abnormalities of corpus callosum and/or cerebellum, congenital heart defect and left ventricular non-compaction cardiomyopathy. Few patients have been described in the literature and the phenotype data are limited. We report a 17-year-old boy with dolihocephaly, elongated face, strabismus, speech and motor delay, intellectual disability, congenital heart defect (ASD, VSD and Ebstein's anomaly), left ventricular non-compaction cardiomyopathy, bilateral inguinal hernia and cryptorchidism. Additional features included recurrent fractures due to multiple non-ossifying fibromas, thrombocytopenia, and renal anomalies. Exome sequencing revealed a de novo pathogenic variant (NM_001145408.2: c.348+2_ 348+15del) in intron 5 of the NONO gene. Renal anomalies and thrombocytopenia have been rarely reported in patients with NONO-X-linked intellectual disability syndrome, while recurrent fractures due to multiple non-ossifying fibromas have not previously been associated with this syndrome. The phenotypic spectrum of NONO-X-linked intellectual disability syndrome may be broader than currently known.

IMMUNOHISTOCHEMICAL ANALYSIS BY KI67 AND IDH1 IN PATIENTS WITH CHONDROSARCOMA

Objective

To perform an immunohistochemical evaluation using the IDH1 and Ki67 markers in patients who underwent treatment for chondrosarcoma in a reference service center in Brazil.

Methods

Retrospective analytical observational study using medical records of patients diagnosed with chondrosarcoma. Besides the epidemiological and clinical profile, important variables for prognosis and correlation with immunohistochemical analysis results with Ki67 and IDH1 markers were evaluated.

Results

Histopathological examinations by immunohistochemistry of 56 patients were analyzed, 52% of which were women, with the age group 20-60 years being more prevalent. Grade 1 and 2 histological subtypes corresponded to most chondrosarcomas. The femur, humerus, and tibia were the most frequent anatomical sites. Most tumors (59%) were larger than 8 cm. Ki67 expression was very low (< 10%) in 98% of patients. The analysis of IDH1 was positive in 43% of the cases. The correlation between IDH1 positivity and tumor size was statistically significant, but regarding survival, we observed no significance.

Conclusion

Immunohistochemical analysis using IDH1 and Ki67 markers in patients with conventional chondrosarcoma is not useful for prognostic guidance.Level of Evidence II, Prognostic Assessment, Results of Immunohistochemical Tests and Correlation with Survival.

Nonvascularized Double Metatarsal Transfer After Excision of Epithelioid Hemangioma of Hand: A Case Report

CASE

Epithelioid hemangioma (EH) is an uncommon, benign, locally aggressive neoplasm, and it may present as multifocal lytic lesions with soft tissue involvement in the hand. We report the midterm follow-up of a patient with recurrent EH of the hand that was reconstructed successfully, with a nonvascularized double metatarsal transfer, after tumor excision. To the best of the authors' knowledge, this is the first case report where a nonvascularized double metatarsal transfer has been used successfully after tumor resection.

CONCLUSION

Osteoarticular replacement with matched metatarsal transfer after en bloc resection may be used successfully for reconstruction, after the resection of EH involving the metacarpal.

Total Joint Replacement for Immediate Reconstruction following Ablative Surgery for Primary Tumors of the Temporo-Mandibular Joint

Temporomandibular joint (TMJ) tumors are rare and difficult to diagnose. The purpose of this retrospective study was to evaluate the clinicopathologic characteristics of twenty-one patients with primary TMJ tumors between 2010 and 2019 and to analyze the surgical outcome and morbidity after ablative surgery and TMJ replacement. This case series confirmed the difficulty of diagnosis and reaffirmed the need for early recognition and management of TMJ tumors. There were no pathognomonic findings associated with TMJ tumors, although single or multiple radiopaque or radiolucent areas were observed on plain or panoramic radiographs. Occasionally, bone resorption or mottled densities caused by pathologic calcification and ossification were seen. Computed tomography and magnetic resonance imaging played an important role in the diagnosis. In our study, the distribution of histologic types of TMJ tumors was quite different from that of other joint tumors. The recommended treatment was surgical intervention by ablation of the joint and TMJ replacement. The results of this retrospective study support the surgical exeresis and replacement with TMJ stock and custom-made prostheses and show that the approach is efficacious and safe, reduces pain and improves mandibular movements, with few complications.

A Rare Giant Cell Tumour in the Distal Radius of a Seven-Year-Old Girl: A Case Report

A giant cell tumour (GCT) is a benign and locally aggressive tumour that is usually observable in a skeletally mature patient involving the end of long bones. The reported incidence of this tumour in a skeletally immature patient is extremely rare. However, we report one such case in the distal radius of a seven-year-old female patient. Having presented with painful swelling of the right distal forearm, she underwent clinical and radiological examination, and a diagnosis of distal radius GCT was made. The tumour was treated with curettage, fibular graft, and synthetic bone graft. This case report shows the importance of including GCT in children as a differential diagnosis. This tumour may have a good prognosis if diagnosed and treated early.

PLGA-based drug delivery systems in treating bone tumors

Bone tumor has become a common disease that endangers human health. Surgical resection of bone tumors not only causes biomechanical defects of bone but also destroys the continuity and integrity of bone and cannot completely remove the local tumor cells. The remaining tumor cells in the lesion bring a hidden danger of local recurrence. To improve the chemotherapeutic effect and effectively clear tumor cells, traditional systemic chemotherapy often requires higher doses, and high doses of chemotherapeutic drugs inevitably cause a series of systemic toxic side effects, often intolerable to patients. PLGA-based drug delivery systems, such as nano delivery systems and scaffold-based local delivery systems, can help eliminate tumors and promote bone regeneration and therefore have more significant potential for application in bone tumor treatment. In this review, we summarize the research progress of PLGA nano drug delivery systems and PLGA scaffold-based local delivery systems in bone tumor treatment applications, expecting to provide a theoretical basis for developing novel bone tumor treatment strategies.

MDM2 Implications for Potential Molecular Pathogenic Therapies of Soft-Tissue Tumors

Murine double minute 2 (MDM2, gene name MDM2) is an oncogene that mainly codes for a protein that acts as an E3 ubiquitin ligase, which targets the tumor suppressor protein p53 for degradation. Overexpression of MDM2 regulates the p53 protein levels by binding to it and promoting its degradation by the 26S proteasome. This leads to the inhibition of p53's ability to regulate cell cycle progression and apoptosis, allowing for uncontrolled cell growth, and can contribute to the development of soft-tissue tumors. The application of cellular stress leads to changes in the binding of MDM2 to p53, which prevents MDM2 from degrading p53. This results in an increase in p53 levels, which triggers either cell cycle arrest or apoptosis. Inhibiting the function of MDM2 has been identified as a potential therapeutic strategy for treating these types of tumors. By blocking the activity of MDM2, p53 function can be restored, potentially leading to tumor cell death and inhibiting the growth of tumors. However, further research is needed to fully understand the implications of MDM2 inhibition for the treatment of soft-tissue tumors and to determine the safety and efficacy of these therapies in clinical trials. An overview of key milestones and potential uses of MDM2 research is presented in this review.