Chondrosarcoma From Floating and Nonfloating Ribs Presenting as a Floating Abdominal Tumor: A Case Report on a Rare Medical Condition.

Chondrosarcoma is a soft tissue tumor that develops in cartilage cells. It can exhibit an aggressive growth tendency when compared to the chondrosarcomas developing in other regions of the body. Clinical presentation of these tumors can also vary depending on the site of presentation. We aim to present the case of a 69-year-old male with a swelling in the chest extending into the abdomen. It is a rare condition that is treated surgically by wide local excision of the tumor.

Clinical, imaging and pathological features of extraskeletal myxoid chondrosarcoma.

OBJECTIVE: To evaluate clinical and radiological features of extraskeletal myxoid chondrosarcomas (EMC). MATERIAL AND METHODS: Our pathology database was queried for cases of EMCs. Tumor location, size, imaging appearance, presence of metastases, disease recurrence, and clinical outcome were documented. Imaging studies were evaluated in consensus by a musculoskeletal radiologist and an orthopedic oncologist. RESULTS: Thirty subjects met the inclusion criteria (mean age 52.7 ± 16.2 years; 19 male, 11 female), 17 (56.7%) of which had pre-operative imaging. Tumors occurred most often in the lower extremities (20/30; 66.7%). All cases presented as a soft-tissue mass without mineralization on XR or CT. On MRI, tumors were typically hyperintense on T2-weighted sequences (14/14; 100%) and had a chondroid matrix appearance (12/14; 85.7%). Tumor invasion was observed in 11 out of 16 (68.9%) patients and necrosis in 2 out of 11 subjects (18.2%). All subjects had their tumors examined by pathology, and 20 (66.7%) subjects also had descriptive information in addition to the diagnosis (tumor invasion, mitotic rate, and necrosis) noted in the pathology reports. The mean duration of follow-up was 9.4 ± 7.5 (1.0 - 29.6) years. At the last follow-up, 14 out of 28 (50%) subjects were disease-free, 6 out of 28 had persistent metastatic disease and 8 out of 28 had died. CONCLUSIONS: EMC is a rare sarcoma that commonly presents as lower extremity soft tissue mass with chondroid appearance on MRI. Unlike conventional chondrosarcomas, EMC do not demonstrate mineralization on XR or CT.

Undifferentiated High-Grade Pleomorphic Bone Sarcoma: A Case Report.

Undifferentiated pleomorphic bone sarcoma (UPS-B) is a rare high-grade sarcoma of bone that is usually seen in advanced age. There is no specific line or pattern of differentiation, and the diagnosis is often made by exclusion. It is especially important to differentiate it from osteosarcoma and dedifferentiated chondrosarcoma. It tends to be located most frequently in the lower extremity, particularly the femur. It is treated with the osteosarcoma protocol. In this study, a case of undifferentiated high-grade pleomorphic bone sarcoma located in the distal femur was reported. It aimed to discuss the patient's clinical presentation, diagnostic approach, treatment, and follow-up process in light of the literature. In this case, the tumor was resected with wide margins after neoadjuvant chemotherapy. He died of diffuse lung metastases during the adjuvant chemotherapy process. Unlike the literature, the patient was only 29 years old. The patient died 8 months after the first diagnosis.

Global research development of chondrosarcoma from 2003 to 2022: a bibliometric analysis.

Background: Chondrosarcomas are common primary malignant bone tumors; however, comprehensive bibliometric analysis in this field has not yet been conducted. Therefore, this study aimed to explore the research hotspots and trends in the field of chondrosarcoma through bibliometric analysis to help researchers understand the current status and direction of research in the field. Methods: Articles and reviews related to chondrosarcoma published between 2003 and 2022 were retrieved from the Web of Science. Countries, institutions, authors, journals, references, and keywords in this field were visualized and analyzed using CtieSpace and VOSviewer software. Results: Between 2003 and 2022, 4,149 relevant articles were found. The number of articles published on chondrosarcoma has increased significantly annually, mainly from 569 institutions in China and the United States, and 81 in other countries. In total, 904 authors participated in the publication of studies related to chondrosarcomas. Over the past 20 years, articles on chondrosarcoma have been published in 958 academic journals, with Skeletal Radiology having the highest number of publications. Furthermore, keywords such as "gene expression," "radiotherapy," "experience," and "apoptosis" have been popular in recent years. Conclusion: Over the past 20 years, the global trend in chondrosarcoma research has primarily been clinical research, with basic research as a supplement. In the future, communication and exchange between countries and institutions should be strengthened. Further, the future main research hotspots in the field of chondrosarcoma include mutated genes and signaling pathways, precision surgical treatment, proton therapy, radiation therapy, chemotherapy, immunotherapy, and other aspects.

The Role of Deubiquitinating Enzymes in Primary Bone Cancer.

Bone is a living, intricate, and dynamic tissue providing locomotion and protection of the body. It also performs hematopoiesis and mineral homeostasis. Osteosarcoma (OS), Ewing sarcoma (ES), and chondrosarcoma (CS) are primary bone cancers. OS and ES mostly develop in younger individuals, and CS generally develops in adults. Ubiquitination regulates numerous cellular processes. The deubiquitinating enzymes (DUBs) detach the ubiquitin molecules from the ubiquitin labeled substrate, altering ubiquitinated protein functions and regulating protein stability via various signaling pathways. Protein homeostasis and bone remodeling are both crucially influenced by the UPS. Recently, there have been several reports on DUBs involved in bone homeostasis and various bone disorders through the regulation of osteoblasts and osteoclasts via NF-κB, Wnt/ß-catenin, TRAF6, TGFß, ERK1/2, and PI3K/Akt pathways. However, DUBs regulating function in bone homeostasis is still in its infancy. Here, we summarized several recent identifications on DUBs, with a focus on their role in bone cancer progression. Therefore, the study attempts to summarize association with the expression level of DUBs as key factors driving bone cancers and also provide new insights on DUBs as key pharmacologic targets for bone cancer therapeutics.

Case report: A mesenchymal chondrosarcoma with alternative HEY1::NCOA2 fusions in the sella turcica.

Introduction: Mesenchymal chondrosarcoma (MCS) is a rare subtype of chondrosarcoma that occurs at widespread anatomical locations, such as bone, soft tissue, and intracranial sites. The central nervous system (CNS) is one of the most common origins of extraosseous MCS. However, alternative HEY1::NCOA2 fusions have not been reported in this tumor. Case report: We report a case of intracranial MCS with HEY1::NCOA2 rearrangement. A 52-year-old woman presented with a 15-mm calcified mass around the sella turcica. She initially underwent transsphenoidal surgery for tumor resection and then additional resections for five local recurrences over 5 years. Histologically, the tumor was composed of small round to spindle-shaped cells admixed with well-differentiated hyaline cartilaginous islands. A hemangiopericytoma-like vascular pattern and small sinusoid-like vessels were also observed. RNA sequencing using RNA extracted from formalin-fixed paraffin-embedded samples from the last operation revealed two alternative variants of the HEY1::NCOA2 fusion: HEY1(ex4)::NCOA2 (ex13) and HEY1(ex4)::NCOA2(ex14). Both variants were confirmed as in-frame fusions using reverse transcription-polymerase chain reaction. Discussion: Cartilaginous components were often not apparent during the recurrences. In addition to the non-typical pathological finding, the correct diagnosis was hampered by the poor RNA quality of the surgical specimens and non-specific STAT6 nuclear staining. Conclusion: This is the first reported case of intracranial MCS with an alternative HEY1::NCOA2 fusion.

Giant Solitary Sinonasal Enchondroma: A Rare Case Report.

Enchondromas, common benign intramedullary cartilaginous tumors, typically arise asymptomatically in metaphysis and diaphysis. We report a case diagnosed and treated for a giant sinonasal enchondroma, an extremely uncommon localization. Few cases have been reported in this location, and additional data is needed to draw conclusions regarding the potential for malignancy. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-024-04620-z.

Novel machine-learning prediction tools for overall survival of patients with chondrosarcoma: Based on recursive partitioning analysis.

BACKGROUND: Chondrosarcoma (CHS), a bone malignancy, poses a significant challenge due to its heterogeneous nature and resistance to conventional treatments. There is a clear need for advanced prognostic instruments that can integrate multiple prognostic factors to deliver personalized survival predictions for individual patients. This study aimed to develop a novel prediction tool based on recursive partitioning analysis (RPA) to improve the estimation of overall survival for patients with CHS. METHODS: Data from the Surveillance, Epidemiology, and End Results (SEER) database were analyzed, including demographic, clinical, and treatment details of patients diagnosed between 2000 and 2018. Using C5.0 algorithm, decision trees were created to predict survival probabilities at 12, 24, 60, and 120 months. The performance of the models was assessed through confusion scatter plot, accuracy rate, receiver operator characteristic (ROC) curve, and area under ROC curve (AUC). RESULTS: The study identified tumor histology, surgery, age, visceral (brain/liver/lung) metastasis, chemotherapy, tumor grade, and sex as critical predictors. Decision trees revealed distinct patterns for survival prediction at each time point. The models showed high accuracy (82.40%-89.09% in training group, and 82.16%-88.74% in test group) and discriminatory power (AUC: 0.806-0.894 in training group, and 0.808-0.882 in test group) in both training and testing datasets. An interactive web-based shiny APP (URL: https://yangxg1209.shinyapps.io/chondrosarcoma_survival_prediction/) was developed, simplifying the survival prediction process for clinicians. CONCLUSIONS: This study successfully employed RPA to develop a user-friendly tool for personalized survival predictions in CHS. The decision tree models demonstrated robust predictive capabilities, with the interactive application facilitating clinical decision-making. Future prospective studies are recommended to validate these findings and further refine the predictive model.

Clival chordomas and chondrosarcomas in Denmark-Outcomes in 33 patients following the national centralization of treatment in 2010.

PURPOSE: This 13-year consecutive case series aims to provide a comprehensive overview of all patients operated for clival chordomas and clival chondrosarcomas in Denmark since the centralization of treatment in 2010, comparing outcomes to international series. METHODS: This was a retrospective review of 33 patients with clival tumors, comprising 22 chordomas and 11 chondrosarcomas, who were treated at Copenhagen University Hospital between years 2010 and 2023. Data were collected from digital patient records and pathology reports. RESULTS: The symptoms leading to diagnosis primarily included double vision, headaches, and dizziness. In general, patients were in good health, with a mean Charlson Comorbidity Index score of 1.6. The complication rate of the index surgery was 51.5%. Adjuvant radiotherapy was applied in 51.5% of the cases. In patients with clival chordomas, the mean age was 51.1 years, ranging from 16 to 83 years. At the time of diagnosis, the mean tumor volume was 20.9 cm3 and the five-year overall survival rates were 79.1% (95% confidence interval (CI): 62.4-100). In patients with chondrosarcomas, the mean age was 48.2 years, ranging from 15 to 76 years. At the time of diagnosis, the mean tumor volume was 22.3 cm3 and the five-year overall survival 90% (95% CI: 73.2-100). CONCLUSION: The centralized treatment of clival tumors in Denmark demonstrates incidence, survival, and complication rates comparable to those found in other international series. Given the variations in treatment strategies, tumor localizations across series, and small sample sizes, the further analysis of larger compiled multicenter datasets for clival tumors could provide more solid evidence regarding the management of these rare tumors.

Chondrosarcoma Co-Culture 3D Model─An Insight to Evaluate Drugs Acting on TAMs.

Chondrosarcoma (CHS), also known as malignant cartilage tumors, is the second most common bone cancer after osteosarcoma. This tumor is particularly chemo- and radioresistant, and the only therapeutic alternative is surgery with wide margins. The tumor immune microenvironment reveals an infiltration of tumor-associated macrophages (TAMs) sometimes approaching 50% of the tumor mass, mainly differentiated into M2-like phenotype and correlated with poor prognosis and metastasis. Thus, macrophage-targeting therapies could have an interest in the management of CHS. To evaluate these strategies, we propose here the development of a three-dimensional (3D) tumoroid co-culture model between two human CHS cell lines (JJ012 and CH2879) and a human leukemia monocytic cell line (THP-1) in a methylcellulose matrix. These two models were compared to the in vivo xenograft models in terms of macrophage phenotypes, proteoglycans, MMP-9, and COX-2 expression. Finally, mifamurtide, an immunomodulator acting on TAMs, was evaluated on the most in vitro relevant model: 3D co-culture CH2879 model. Our results showed that it is now possible to develop 3D models that very accurately mimic what is found in vivo with the possibility of evaluating treatments specific to a tumor cell component.

Limb Salvage in Chondrosarcoma of the Proximal Humerus: A Case Report.

Chondrosarcoma is the third most common primary malignant bone tumor. The proximal humerus is the most common site. Since it is resistant to chemotherapy and radiotherapy, the mainstay of treatment is surgery. Due to the extensive involvement of long bones, it requires reconstruction with either a prosthetic implant or bone graft. We present a case of a 43-year-old female who presented with chondrosarcoma involving 15 cm of humerus. The patient was managed with the resection of 15 cm of humerus and reconstruction with the same resected bone after autoclaving. It was secured with long fixation resulting in arthrodesis of the glenohumeral joint. The patient was followed for one year and there was evidence of callus formation by ultrasound and computed tomography (CT) scan.

Fourteen-Year Follow-Up of a Patient With a Hydroxyapatite Ceramic Matrix Reconstruction of and a Bone Graft for a Critical-Size Cortical Bone Defect: A Case Report.

A 42-year-old man diagnosed with chondrosarcoma of the proximal femur underwent limb salvage by compartmental excision of the lesion and reconstruction with a custom-made hip prosthesis. The critical-size defect in the proximal femur was reconstructed with ceramic hemicylinders that were tied in place with sutures and augmented with two fibular strut grafts and an autologous cancellous iliac crest bone graft. A fourteen-year follow-up of the same case revealed that substituted ceramic matrices can be converted into dynamic, metabolically active, living bone.

Principles of Defect Reconstruction After Wide Resection of Primary Malignant Bone Tumors of the Calcaneus: A Contemporary Review.

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Targeting Isocitrate Dehydrogenase (IDH) in Solid Tumors: Current Evidence and Future Perspectives.

The isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) enzymes are involved in key metabolic processes in human cells, regulating differentiation, proliferation, and oxidative damage response. IDH mutations have been associated with tumor development and progression in various solid tumors such as glioma, cholangiocarcinoma, chondrosarcoma, and other tumor types and have become crucial markers in molecular classification and prognostic assessment. The intratumoral and serum levels of D-2-hydroxyglutarate (D-2-HG) could serve as diagnostic biomarkers for identifying IDH mutant (IDHmut) tumors. As a result, an increasing number of clinical trials are evaluating targeted treatments for IDH1/IDH2 mutations. Recent studies have shown that the focus of these new therapeutic strategies is not only the neomorphic activity of the IDHmut enzymes but also the epigenetic shift induced by IDH mutations and the potential role of combination treatments. Here, we provide an overview of the current knowledge about IDH mutations in solid tumors, with a particular focus on available IDH-targeted treatments and emerging results from clinical trials aiming to explore IDHmut tumor-specific features and to identify the clinical benefit of IDH-targeted therapies and their combination strategies. An insight into future perspectives and the emerging roles of circulating biomarkers and radiomic features is also included.

Specific spectral sub-images for machine learning evaluation of optical differences between carbon ion and X ray radiation effects.

Advances in radiotherapy, particularly the exploration of alternative radiation types such as carbon ions have updated our understanding of its effects and applicability on chondrosarcoma cells. Here we compare the optical effects produced by carbon ions (CI) and X-rays (XR) radiations on chondrosarcoma cells nuclei and set an automated method for evaluating the radiation-induced alterations without the need of chemical marking. Hyperspectral images (HSI) of SW1353 chondrosarcoma line carry detectable optical changes of the cells irradiated either with CI or XR compared to non-irradiated ones (REF). The differences between the spectral profiles of CI, XR and REF nuclei classes led to partitioning the HSIs into spectral sub-images. The changes are detected by support vector machine (SVM) classifiers whose performances are evaluated by the most used point metrics: sensitivity (SEN), accuracy (ACC), and precision (PREC), applied on spatial feature values. Specific interaction mechanisms by radiation type reveal distinct subintervals where HSIs changes are more prominent, and the classifiers perform at best. For CI the best classifiers are obtained for sub-images in the interval (424-436 nm), while for XR the best classifiers are obtained for sub-images in the interval (436-445 nm). The classifiers work better with texture features than roughness features in both cases. The classifier with the best SEN point metric in the testing phase is the most suitable to measure the irradiation efficiency irrespective of the radiation type. The altered nuclei are easier to discriminate when irradiated with CI than with XR. The study proves that SVM with optical data offers a rapid, automated, and label-free method for evaluating radiation-induced alterations in chondrosarcoma nuclei, thereby enabling effective analysis of extensive data.

Lumbar Vertebral Fracture Through a Pre-Existing Schmorl's Node Mimicking Histopathologically a Low-Grade Chondrosarcoma.

The aim of this paper is to present a unique, to the best of our knowledge, case of a patient with a fracture of the first lumbar vertebra (L1), which occurred through a pre-existing Schmorl's node (SN), with histopathological characteristics mimicking a low-grade chondrosarcoma that initially led to a false diagnosis. A 54-year-old woman tripped and fell to the ground, sustaining a fracture of the L1 vertebral body. She was treated conservatively with gradual mobilization using a thoracolumbar brace for six weeks. Due to persistent pain and her inability to achieve full mobilization, she was offered vertebral kyphoplasty. During the same operative session and just before the kyphoplasty, she underwent a core-needle biopsy of the affected area. Following her operation, she reported a gradual, yet quick and full remission of her symptoms. The pathology report indicated findings consistent with a low to mid-grade chondrosarcoma. A re-evaluation of the specimen by a different pathologist confirmed the diagnosis of low-grade chondrosarcoma. Subsequently, she underwent full oncological staging, which was negative for metastases. Additional imaging studies failed to show signs of local disease progression. Due to the discordance between the pathology reports and the imaging and clinical findings, her case was referred to our specialized center for spinal tumor surgery. A new pathological re-evaluation of the biopsy samples was performed, and the diagnosis of low-grade chondrosarcoma was once again confirmed. However, during the multidisciplinary tumor (MDT) meeting that followed, and after careful evaluation of subsequent imaging studies that showed signs of local improvement and due to the complete lack of symptoms, the histopathological findings were re-evaluated and attributed to the fracture occurring through a pre-existing SN penetrating the cancellous bone of the vertebra. This complex situation contributed to histopathological findings consistent with a well-differentiated chondrosarcoma. The patient remains symptom-free 10 months following her operation and has fully returned to her previous activities. Our unique case highlights the importance of an MDT meeting when evaluating patients with musculoskeletal tumors and emphasizes the need for increased awareness when clinical findings and imaging studies are in discordance with histopathology reports.

Surgical management of chondrosarcomas of the skull-base and temporal bone.

OBJECTIVES: To analyze the overall long-term outcome of surgically treated skull base and temporal bone chondrosarcomas. METHODS: The medical records of patients with surgically treated skull base and temporal bone chondrosarcomas between 1983 and 2024 were thoroughly evaluated. RESULTS: Out of a total of over 5000 skull base surgeries performed at our center, only 29 patients had histopathologically confirmed chondrosarcomas of the skull base and temporal bone. The mean of patients age was 45.6, and the male-to-female ratio was 1.9:1. The most common symptoms included hearing loss (58.6%), tinnitus (41.4%), diplopia (31%), dysphonia (24.1%), dysphagia (20.7%), vertigo (10.3%), and dizziness (10.3%). The most frequent locations of lesions among the 29 patients are as follows: petroclival region (34.5%), jugular foramen (27.6%), petrous apex (17.2%), middle ear (13.8%), others (3.4%). TO, IFTA, IFTB, IFTC, POTS, and combined surgical approaches were commonly used. The rate of gross total removal and recurrence was 82.6% and 13.8% respectively. The follow-up duration of 6 patients was more than five years and less than ten years whereas ten patients had more than ten years of follow-up. CONCLUSIONS: Chondrosarcoma of the skull base and temporal bone is a very rare pathology. Due to its multiple potential sites of origin and histological specificity, it presents us with significant challenges. Gross total removal is the primary treatment for chondrosarcoma of the skull base and temporal bone. Personalized decision-making should be considered based on the following aspects: tumor, patient, and surgeon's factors. Postoperative radiation therapy is complementary to surgical treatment in grades II and III lesions to achieve long-term survival.

Surgical Management and Reconstruction of Dedifferentiated Chondrosarcoma in the Proximal Femur: A Case Report.

A primary malignant bone tumor, or more commonly, metastasis, can occur in the proximal femur. Surgical treatment can have palliative or curative purposes. In the case of the latter, it involves two stages: resection of the tumor, which aims to address the cancer, and reconstruction of the bone and soft tissue, which aims to restore function. It is important for the excision to be wide with adequate resection margins in the soft tissue, particularly when the goal is curative treatment. Typically, surgery involves excision and reconstruction to ensure good mechanical stability. Reconstruction can be done using different methods, such as a composite prosthesis or a massive prosthesis, which may be modular or custom-made. Joint reconstruction options include hemiarthroplasty, intermediate prosthesis, or, in some cases, total hip replacement.

Chondrosarcoma of the Mobile Spine in the Elderly: A National Cancer Database Study.

BACKGROUND: The current research on geriatric patients with spinal chondrosarcoma is limited. This study aimed to investigate the demographics, patterns of care, and survival of geriatric patients with chondrosarcoma of the mobile spine. METHODS: The National Cancer Database was queried from 2008 to 2018 for geriatric patients (60-89 years) with chondrosarcoma of the mobile spine. The primary outcome of this study was overall survival. The secondary outcome was treatment utilization patterns. Survival analyses were conducted using log-rank tests and Cox proportional hazards regressions. Logistic regression models were utilized to assess correlations between baseline variables and treatment utilization. RESULTS: The database retrieved 122 patients. While 43.7% of the patients presented with tumors exceeding 5 cm in size, the incidence of regional lymph node involvement or distant metastases was relatively low, affecting only 5% of the patients. Furthermore, 22.3% of the patients had tumors graded as 3-4. The 5-year overall survival rate was 52.9% (95% confidence interval: 42-66.6). The mortality risk was significantly associated with age, tumor grade and stage, and treatment plan. Most patients (79.5%) underwent surgery, while 35.9% and 4.2% were treated with radiotherapy and chemotherapy, respectively. Age, race, comorbidities, geographical region, tumor stage, and healthcare facility type significantly correlated with treatment utilization. CONCLUSIONS: Surgical resection significantly lowered the mortality risk in geriatric patients with spinal chondrosarcomas. Demographic and geographical factors significantly dictated treatment plans. Further studies are required to assess the role of radiotherapy and chemotherapy in treating these patients in the modern era.

Nasal clear cell chondrosarcoma in a dog.

An intranasal tumour was diagnosed in a 5-year-old male neutered crossbreed dog following a 6-8 week history of intermittent epistaxis and nasal discharge. Computed tomography identified a mass in the right nasal cavity. Histologically, the mass was composed of sheets and indistinct clusters of predominantly clear or vacuolated round to polygonal cells; periodic acid-Schiff staining revealed glycogen granules within some tumour cells. Immunohistochemical labelling revealed that the tumour cells were immunopositive for vimentin and S100 and negative for pancytokeratin, Melan-A and PNL2, supporting a diagnosis of a clear cell variant of chondrosarcoma (CCC). Although the dog was treated with meloxicam, the owners opted for euthanasia 9 days after presentation. Considering that there is only one other reported case of a suspected CCC in a dog, also in the nasal cavity, this could represent a species-specific predilection site of this rare canine neoplasm.