Unusual soft tissue metastases in a patient with chondrosarcoma: a case report.

Chondrosarcoma (CS) is the second most frequent primary malignant bone tumour, characterized by production of non-osteoid cartilage matrix. Up to more than 30% of patients with CS present distant metastases, and the lungs represent the preferred site. Hence, CS soft tissue metastases and superficial cutaneous lesions are extremely rare. We report the case of a female who developed unusual multiple soft tissue CS metastases. This patient underwent left hindquarter amputation for recurrent grade 3 chondrosarcoma of the femoral neck with extension to the pelvis approximately 4 years after internal fixation with an intramedullary nail for pathological fracture of left proximal femur and subsequent total proximal femoral endoprosthetic replacement for grade 1-2 chondrosarcoma. In the following years, she underwent metastasectomy for several grade 2 pulmonary metastatic chondrosarcomas. More than 14 years after the amputation, she presented with multiple unusual superficial cutaneous lesions, and a whole-body magnetic resonance imaging demonstrated multiple soft tissue foci of metastatic disease. The histology of multiple soft tissue lesions excised confirmed metastatic chondrosarcoma. Then, she underwent marginal excision of further multifocal soft tissue metastatic high-grade chondrosarcoma. Unlike the poor survival from the onset of these metastases in the other cases reported in the literature, our patient is still alive 2 years after the first multiple soft tissue excision of metastatic chondrosarcoma, and approximately 20 years after the diagnosis of chondrosarcoma. Soft tissue CS metastases are a rare entity with few cases described in literature. This study aims to make the reader aware of this lesser-known CS manifestation.

Grade III chondrosarcoma of the left iliopubic branch: A case report.

INTRODUCTION AND IMPORTANCE: Chondrosarcomas are the third most frequent malignant bone tumors. With pelvic bones being their most common primary location, diagnosis and treatment of these tumors is especially challenging due to the diverse clinical manifestations and involvement of critical anatomic structures. We present the case of a grade III pelvic chondrosarcoma of the left iliopubic branch managed through a multidisciplinary approach. CASE PRESENTATION: A 26-year-old male patient presented with a 1-year history of a mass in the left iliopubic branch. The imaging findings suggested chondrosarcoma and showed extrinsic compression of pelvic structures causing right hydronephrosis, marked elongation and tortuosity of the sigmoid colon, and anterior and superior displacement of the bladder. Following multidisciplinary meeting it was decided to perform a left hemicolectomy, colostomy, and internal hemipelvectomy in the 1-2-3 left zones, with resection of the intrapelvic and intra-abdominal tumor, and preservation of the left lower extremity. The patient presented two episodes of intestinal obstruction, which resolved with medical management. Was discharged without presenting further complications. CLINICAL DISCUSSION: Chondrosarcomas management demands a methodical approach. Appropriate surgical strategy requires individualization according to the characteristics of the lesion and the degree of involvement of surrounding structures. Complete resection of the tumor and preservation of the lower extremity function are critical achievements. CONCLUSION: This case underscores the effective management of a challenging tumor such as pelvic chondrosarcoma. The multidisciplinary approach and collaboration of several specialties was crucial to reach an appropriate surgical strategy.

Combining morphological and functional imaging parameters to diagnose primary bone neoplasms in the skull base, spine and sacrum.

PURPOSE: Morphological magnetic resonance (MR) and computed tomography (CT) features are used in combination with histology for diagnosis and treatment selection of primary bone neoplasms. Isolated functional MRI parameters have shown potential in diagnosis. Our goal is to facilitate diagnosis of primary bone neoplasms of the skull base, mobile spine and sacrum, by a comprehensive approach, combining morphological and functional imaging parameters. MATERIALS AND METHODS: Pre-treatment MR of 80 patients with histologically proven diagnosis of a primary bone neoplasm of the skull base, mobile spine and sacrum were retrospectively analyzed for morphological and functional MRI parameters. Functional parameters were measured in 4 circular regions of interest per tumor placed on non-adjacent scan slices. Differences in values of functional parameters between different histologies were analyzed with Dunn's test. RESULTS: Chordomas were the predominant histology (60.0%). Most neoplasms (80.0%) originated in the midline and had geographical (78.2%) bone destruction. Amorphous-type calcification (pre-existing bone) was seen only in chordomas. Homogeneous contrast enhancement pattern was seen only in chondrosarcoma and plasmacytoma. Ktrans and Kep were significantly lower in both chordoma, and chondrosarcoma compared to giant cell tumor of the bone (p = 0.006 - 0.011), and plasmacytoma (p = 0.004 - 0.014). Highest diffusion-weighted MRI apparent diffusion coefficient (ADC) values corresponded to chondrosarcoma and were significantly higher to those of chordoma (p = 0.008). CONCLUSION: We identified the most discriminating morphological parameters and added functional MR parameters based on histopathological features that are useful in making a confident diagnosis of primary bone neoplasms in the skull base, mobile spine and sacrum.

Primary Extraskeletal Falcine Myxoid Chondrosarcoma-A Case Report and Review of Literature.

Intracranial chondrosarcomas are rare malignant lesions. Both skull base and dural-based extraosseous chondrosarcomas have been reported to occur intracranially. Dural-based chondrosarcomas arising from the falx cerebri are rare lesions with only 19 cases reported till date. Although conventional, mesenchymal, and myxoid variants of chondrosarcomas have been reported intracranially, myxoid variant are the rarest with only 17 cases reported till date, among which only 2 were falcine. We are reporting the third case of falcine myxoid chondrosarcoma in a 32-year-old man who presented with seizures and subtle lower limb weakness. Radiological findings were suggestive of an atypical meningioma in the falcine region. Macroscopically total resection of the tumor was done. Histopathological examination confirmed myxoid chondrosarcoma, grade 1. Postoperative period was uneventful, and the patient remains asymptomatic 34 months after the surgery without the application of any adjuvant therapy. Falcine myxoid chondrosarcomas are extremely rare lesions with variable aggressiveness as suggested by the three cases reported till now including the present case.

Preoperative prediction of histopathological grading in patients with chondrosarcoma using MRI-based radiomics with semantic features.

BACKGROUND: Distinguishing high-grade from low-grade chondrosarcoma is extremely vital not only for guiding the development of personalized surgical treatment but also for predicting the prognosis of patients. We aimed to establish and validate a magnetic resonance imaging (MRI)-based nomogram for predicting preoperative grading in patients with chondrosarcoma. METHODS: Approximately 114 patients (60 and 54 cases with high-grade and low-grade chondrosarcoma, respectively) were recruited for this retrospective study. All patients were treated via surgery and histopathologically proven, and they were randomly divided into training (n = 80) and validation (n = 34) sets at a ratio of 7:3. Next, radiomics features were extracted from two sequences using the least absolute shrinkage and selection operator (LASSO) algorithms. The rad-scores were calculated and then subjected to logistic regression to develop a radiomics model. A nomogram combining independent predictive semantic features with radiomic by using multivariate logistic regression was established. The performance of each model was assessed by the receiver operating characteristic (ROC) curve analysis and the area under the curve, while clinical efficacy was evaluated via decision curve analysis (DCA). RESULTS: Ultimately, six optimal radiomics signatures were extracted from T1-weighted imaging (T1WI) and T2-weighted imaging with fat suppression (T2WI-FS) sequences to develop the radiomics model. Tumour cartilage abundance, which emerged as an independent predictor, was significantly related to chondrosarcoma grading (p < 0.05). The AUC values of the radiomics model were 0.85 (95% CI, 0.76 to 0.95) in the training sets, and the corresponding AUC values in the validation sets were 0.82 (95% CI, 0.65 to 0.98), which were far superior to the clinical model AUC values of 0.68 (95% CI, 0.58 to 0.79) in the training sets and 0.72 (95% CI, 0.57 to 0.87) in the validation sets. The nomogram demonstrated good performance in the preoperative distinction of chondrosarcoma. The DCA analysis revealed that the nomogram model had a markedly higher clinical usefulness in predicting chondrosarcoma grading preoperatively than either the rad-score or clinical model alone. CONCLUSION: The nomogram based on MRI radiomics combined with optimal independent factors had better performance for the preoperative differentiation between low-grade and high-grade chondrosarcoma and has potential as a noninvasive preoperative tool for personalizing clinical plans.

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 (OS). 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 5cm 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 five-year OS 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. CONCLUSION: 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.

Rehabilitation Treatment of a Patient With Total Humeral Endoprosthetic Replacement.

Total humeral endoprosthetic replacement (THR) is a rare surgery for malignant humeral bone tumors. Studies focusing on its surgical methods and functional status are limited. Furthermore, rehabilitation treatment after THR has not been reported. Therefore, this case report aimed to investigate its postoperative rehabilitation treatment and reinstatement. A 69-year-old woman was diagnosed with chondrosarcoma of her left humerus. THR was performed the day following patient admission. The wide resection caused the loss of her left shoulder motor function. She had a left ulnar nerve disorder and carpal tunnel syndrome. Rehabilitation treatments such as joint range of motion training were initiated on postoperative day (POD) 1. We designed a shoulder abductor brace to maintain her left shoulder in an abducted and flexed position so she could use her left hand effectively. The manual muscle testing scores for elbow joint movements gradually improved. On POD47, she was transferred to a convalescent rehabilitation hospital to receive training in activities of daily living and barber work. The patient was discharged on POD107. The Disabilities of the Arm, Shoulder, and Hand score improved from 86.2 (POD7) to 17.2 (POD107). She continued outpatient rehabilitation and reinstated work on POD143. The use of a brace and seamless rehabilitation from the acute phase to convalescence and community-based rehabilitation enabled the patient with THR to return to work. This study suggests that precise assessment of the disorders and consecutive rehabilitation treatment with a brace should be considered after THR.

A combined small cell lung carcinoma patient with only small cell carcinoma components in mediastinal lymph node metastasis and chondrosarcoma-like components in liver metastasis.

A 69-year-old ex-smoker Japanese man presented with a left mediastinal lymph node and left upper lobe tumour. Bronchoscopic biopsy specimens from the enlarged left mediastinal lymph node and left upper lobe tumour revealed small cell lung carcinoma (SCLC). He was treated with first-line chemotherapy with carboplatin, etoposide, and atezolizumab for four courses and subsequent atezolizumab maintenance therapy. However, his left upper lobe lung tumour only increased in size, and left upper lobectomy revealed combined SCLC (adenocarcinoma and chondrosarcoma-like features). Four months after lobectomy, liver metastasis of chondrosarcoma-like features (similar to pathological findings of the left upper lobe tumour) were observed. Combined SCLC, including sarcomatous components, is rare and poorly responds to chemotherapy. The metastases of combined SCLC in this patient were of only one type of histological component, making diagnosis and treatment difficult. If treatment for SCLC responds inadequately, considering combined SCLC and actively re-examining histological diagnosis is necessary.

Application of microwave ablation assisted degradation therapy in surgical treatment of intramedullary chondrosarcoma of extremities.

AIM: Clinical diagnosis and surgical treatment of chondrosarcoma (CS) are continuously improving. The purpose of our study is to evaluate the effectiveness of microwave ablation (MWA) assisted degradation therapy in the surgical treatment of intramedullary chondrosarcoma of the extremities, to provide a new reference and research basis for the surgical treatment of CS. METHODS: We recruited 36 patients with intramedullary CS who underwent MWA assisted extended curettage. Preoperative patient demographics and clinical data were recorded. Surgery was independently assisted by a medical team. Patients were followed up strictly and evaluated for oncological prognosis, radiological results, limb joint function, pain, and complications. RESULTS: We included 15 men and 21 women (mean age: 43.5 ± 10.1). The average length of the lesion was 8.1 ± 2.5 cm. Based on preoperative radiographic, clinical manifestations, and pathological results of puncture biopsy, 28 patients were preliminarily diagnosed with CS-grade I and eight patients with CS-grade II. No recurrence or metastasis occurred in the postoperative follow-up. The average Musculoskeletal Tumor Society score was 28.8 ± 1.0, significantly better than presurgery. Secondary shoulder periarthritis and abduction dysfunction occurred in early postoperative stage CS of the proximal humerus in some, but returned to normal after rehabilitation exercise. Secondary bursitis occurred at the knee joint in some due to the internal fixation device used in treatment; however, secondary osteoarthritis and avascular necrosis of the femoral head were not observed. Overall, oncological and functional prognoses were satisfactory. CONCLUSIONS: The application of MWA assisted degradation therapy in intramedullary CS can achieve satisfactory oncology and functional prognosis, providing a new option for the limited treatment of CS.

Cold Physical Plasma Reduces Motility of Various Bone Sarcoma Cells While Remodeling the Cytoskeleton.

BACKGROUND/AIM: Cold physical plasma (CPP) has emerged as an effective therapy in oncology by inducing cytotoxic effects in various cancer cells, including chondrosarcoma (CS), Ewing's sarcoma (ES), and osteosarcoma (OS). The current study investigated the impact of CPP on cell motility in CS (CAL-78), ES (A673), and OS (U2-OS) cell lines, focusing on the actin cytoskeleton. MATERIALS AND METHODS: The CASY Cell Counter and Analyzer was used to study cell proliferation and determine the optimal concentrations of fetal calf serum to maintain viability without stimulation of cell proliferation. CellTiter-BlueCell viability assay was used to determine the effects of CPP on the viability of bone sarcoma cells. The Radius assay was used to determine cell migration. Staining for Deoxyribonuclease I, G-actin, and F-actin was used to assay for the effects on the cytoskeleton. RESULTS: Reductions in cell viability and motility were observed across all cell lines following CPP treatment. CPP induced changes in the actin cytoskeleton, leading to decreased cell motility. CONCLUSION: CPP effectively reduces the motility of bone sarcoma cells by altering the actin cytoskeleton. These findings underscore CPP's potential as a therapeutic tool for bone sarcomas and highlight the need for further research in this area.

DNA-PKcs Inhibition Sensitizes Human Chondrosarcoma Cells to Carbon Ion Irradiation via Cell Cycle Arrest and Telomere Capping Disruption.

In order to overcome the resistance to radiotherapy in human chondrosarcoma cells, the prevention from efficient DNA repair with a combined treatment with the DNA-dependent protein kinase catalytic subunit (DNA-PKcs) inhibitor AZD7648 was explored for carbon ion (C-ion) as well as reference photon (X-ray) irradiation (IR) using gene expression analysis, flow cytometry, protein phosphorylation, and telomere length shortening. Proliferation markers and cell cycle distribution changed significantly after combined treatment, revealing a prominent G2/M arrest. The expression of the G2/M checkpoint genes cyclin B, CDK1, and WEE1 was significantly reduced by IR alone and the combined treatment. While IR alone showed no effects, additional AZD7648 treatment resulted in a dose-dependent reduction in AKT phosphorylation and an increase in Chk2 phosphorylation. Twenty-four hours after IR, the key genes of DNA repair mechanisms were reduced by the combined treatment, which led to impaired DNA repair and increased radiosensitivity. A time-dependent shortening of telomere length was observed in both cell lines after combined treatment with AZD7648 and 8 Gy X-ray/C-ion IR. Our data suggest that the inhibition of DNA-PKcs may increase sensitivity to X-rays and C-ion IR by impairing its functional role in DNA repair mechanisms and telomere end protection.

Emerging Treatments Targeting the Tumor Microenvironment for Advanced Chondrosarcoma.

Chondrosarcoma (ChS), a malignant cartilage-producing tumor, is the second most frequently diagnosed osseous sarcoma after osteosarcoma. It represents a very heterogeneous group of malignant chemo- and radiation-resistant neoplasms, accounting for approximately 20% of all bone sarcomas. The majority of ChS patients have a good prognosis after a complete surgical resection, as these tumors grow slowly and rarely metastasize. Conversely, patients with inoperable disease, due to the tumor location, size, or metastases, represent a great clinical challenge. Despite several genetic and epigenetic alterations that have been described in distinct ChS subtypes, very few therapeutic options are currently available for ChS patients. Therefore, new prognostic factors for tumor progression as well as new treatment options have to be explored, especially for patients with unresectable or metastatic disease. Recent studies have shown that a correlation between immune infiltrate composition, tumor aggressiveness, and survival does exist in ChS patients. In addition, the intra-tumor microvessel density has been proven to be associated with aggressive clinical behavior and a high metastatic potential in ChS. This review will provide an insight into the ChS microenvironment, since immunotherapy and antiangiogenic agents are emerging as interesting therapeutic options for ChS patients.

Additional Role of 3D ASL Perfusion in Skull Base Lesions.

Background Arterial spin labeling (ASL) perfusion imaging is widely used since its main advantage is that no intravenous contrast is needed. Given that perfusion is a crucial biological characteristic for identifying tumor lesions, the qualitative noncontrast perfusion characteristics of these lesions were examined. Aim We attempted utilizing the three-dimensional (3D) ASL technique to characterize skull base lesions and to highlight its crucial role in differentiating lesions. Methods and Material 3D ASL imaging of 20 patients with posterior skull base lesions was performed in a 3-T magnetic resonance (MR) system (Siemens Healthineers, Skyra, Erlangen, Germany). The common differential diagnoses of skull base lesions could be distinguished based on this qualitative evaluation. Results and Conclusions Glomus tumor has a strikingly increased perfusion when compared to meningiomas. The perfusion characteristics of metastasis depends on the primary tumor. Chondrosarcomas have a heterogeneously increased perfusion. Chordomas have variable perfusion, which helps in prognosticating the tumors. ASL benefits pediatric patients and in renal failure as well since it avoids the ethical ambiguity associated with contrast agents.

NAMPT enhances LOX expression and promotes metastasis in human chondrosarcoma cells by inhibiting miR-26b-5p synthesis.

Chondrosarcoma is a malignant bone tumor that emerges from abnormalities in cartilaginous tissue and is related with lung metastases. Nicotinamide phosphoribosyltransferase (NAMPT) is an adipocytokine reported to enhance tumor metastasis. Our results from clinical samples and the Gene Expression Omnibus data set reveal that NAMPT levels are markedly higher in chondrosarcoma patients than in normal individuals. NAMPT stimulation significantly increased lysyl oxidase (LOX) production in chondrosarcoma cells. Additionally, NAMPT increased LOX-dependent cell migration and invasion in chondrosarcoma by suppressing miR-26b-5p generation through the c-Src and Akt signaling pathways. Overexpression of NAMPT promoted chondrosarcoma metastasis to the lung in vivo. Furthermore, knockdown of LOX counteracted NAMPT-facilitated metastasis. Thus, the NAMPT/LOX axis presents a novel target for treating the metastasis of chondrosarcoma.

Incidental Finding of an Atypical Cartilaginous Tumor in an Adult Female with Recurrent Patellar Dislocation: Single-stage Extended Curettage using Freezing Nitrogen Ethanol Composite followed by Medial Patello-Femoral Ligament Reconstruction.

Atypical cartilaginous tumor (ACT) refers to a low-grade cartilaginous neoplasm microscopically identical to grade 1 chondrosarcoma, affecting the appendicular skeleton. Treatment with intralesional curettage has been found to provide sufficient local control with less morbidity compared to wide resection. This is the first reported case of a simultaneous medial patello-femoral ligament (MPFL) reconstruction with extended curettage for ACT on the ipsilateral femur. A 45-year-old female presented with chronic recurrent patellar dislocation of the right knee. Magnetic resonance imaging revealed a tear of the MPFL, with an incidental epi-metaphyseal chondroid lesion. After biopsy confirmed an ACT, single-stage extended curettage using freezing nitrogen ethanol composite (FNEC) and MPFL reconstruction was performed, followed by augmentation with bone cement and a distal femoral plate. Currently, the patient is independently ambulatory, with full range of motion about the knee. Following histologic confirmation of an ACT in the setting of a concurrent MCL tear, a single-stage procedure to address both conditions is a viable option that can reduce complications associated with multiple surgeries. Extended curettage using FNEC has been shown to produce good short-term oncologic outcomes while maximizing function.

Sinonasal chondrosarcoma in a llama.

A 14-y-old intact female llama (Lama glama) was presented for evaluation of a right maxillary swelling of 3-mo duration. Clinically, the animal had mild nasal discharge, abnormal retropulsion of the right eye, and moderate gingival disease. An incisional biopsy of the maxillary mass revealed pleomorphic and mitotically active neoplastic spindle-to-stellate cells organized in haphazard lacunae embedded in abundant chondroid matrix. Given the poor prognosis, euthanasia was elected. Postmortem examination and sectioning of the head exposed a large solid, white, firm mass that vastly expanded the right infraorbital region, extending to the maxilla, effacing the right nasal conchae and ipsilateral zygomatic bone. Collectively, postmortem dissection, cytology, and histopathology of the primary mass supported a diagnosis of sinonasal chondrosarcoma. To our knowledge, this entity had not been reported previously in this species and should be considered a differential for facial deformities in New World camelids.

An Unusual Presentation of a Primary Chondrosarcoma of the Cranial Vault.

Chondrosarcomas are malignant cartilaginous tumors that usually affect the pelvic bone and long bones. Primary chondrosarcomas of the skull are rare, with the cranial vault being an even more unusual localization. We report a case of a 75-year-old man presenting with headaches and outgrowth of the parietal scalp. CT scan of the head showed an extracranial cystic well-rounded mass originating at the parietal suture and eroding through the adjacent parietal bone. The patient underwent an en bloc surgical resection of the mass, and histological examination confirmed a grade I chondrosarcoma.

The ketone body ß-Hydroxybutyrate as a fuel source of chondrosarcoma cells.

Chondrosarcoma (CS) is a malignant bone tumor arising from cartilage-producing cells. The conventional subtype of CS typically develops within a dense cartilaginous matrix, creating an environment deficient in oxygen and nutrients, necessitating metabolic adaptation to ensure proliferation under stress conditions. Although ketone bodies (KBs) are oxidized by extrahepatic tissue cells such as the heart and brain, specific cancer cells, including CS cells, can undergo ketolysis. In this study, we found that KBs catabolism is activated in CS cells under nutrition-deprivation conditions. Interestingly, cytosolic ß-hydroxybutyrate dehydrogenase 2 (BDH2), rather than mitochondrial BDH1, is expressed in these cells, indicating a specific metabolic adaptation for ketolysis in this bone tumor. The addition of the KB, ß-Hydroxybutyrate (ß-HB) in serum-starved CS cells re-induced the expression of BDH2, along with the key ketolytic enzyme 3-oxoacid CoA-transferase 1 (OXCT1) and monocarboxylate transporter-1 (MCT1). Additionally, internal ß-HB production was quantified in supplied and starved cells, suggesting that CS cells are also capable of ketogenesis alongside ketolysis. These findings unveil a novel metabolic adaptation wherein nutrition-deprived CS cells utilize KBs for energy supply and proliferation.

Parosteal osteosarcoma with low grade chondrosarcoma and liposarcoma components. A rare histologic variant. Case report and literature review.

INTRODUCTION: conventional parosteal osteosarcoma is an uncommon malignant bone tumor, comprising 4% of all osteosarcomas. Although rare, parosteal osteosarcoma is the most common type of osteosarcoma of the bone surface. We present the clinical, histological and imaging characteristics of a rare histologic variant of a parosteal osteosarcoma, review the literature and emphasize the importance of radio-pathological correlation as well as the interpretation of a representative biopsy in order to obtain the correct diagnosis. CASE REPORT: a 36-year old woman began her condition one year prior to admission to the hospital with increased volume in the left knee and pain. Image studies showed a juxtacortical heterogeneous tumor localized on the posterior surface of the distal femoral metaphysis. An incisional biopsy was performed, with the diagnosis of a Parosteal Osteosarcoma and a wide surgical resection was undertaken. According to the findings of the surgical specimen, the diagnosis of a Parosteal Osteosarcoma with low grade chondrosarcoma and liposarcoma components was made. The knowledge of this rare parosteal osteosarcoma variant can lead the orthopedic oncologists to avoid overlooking the adipose component and provide adequate surgical margins. CONCLUSION: we present the clinical, histological and imaging characteristics of a Parosteal Osteosarcoma with low grade liposarcoma and chondrosarcoma components.

INTRODUCCIÓN: el osteosarcoma parosteal convencional es un tumor óseo maligno poco común, que comprende el 4% de todos los osteosarcomas. Aunque es poco común, el osteosarcoma parosteal es el tipo más común de osteosarcoma de la superficie ósea. Presentamos las características clínicas, histológicas y de imagen de una variante histológica rara de un osteosarcoma parosteal, revisamos la literatura y enfatizamos la importancia de la correlación radio-patológica, así como la interpretación de una biopsia representativa para obtener el diagnóstico correcto. REPORTE DE CASO: mujer de 36 años inició su cuadro un año antes de su ingreso al hospital con aumento de volumen en rodilla izquierda y dolor. Los estudios de imagen mostraron una tumoración heterogénea yuxtacortical localizada en la superficie posterior de la metáfisis femoral distal. Se realizó biopsia incisional, con diagnóstico de osteosarcoma parosteal y se realizó resección quirúrgica amplia. De acuerdo con los hallazgos de la pieza quirúrgica se realizó el diagnóstico de osteosarcoma parosteal con componentes de condrosarcoma y liposarcoma de bajo grado. El conocimiento de esta rara variante de osteosarcoma parosteal puede llevar a los ortopedistas oncólogos a considerar otros componentes y proporcionar márgenes quirúrgicos adecuados. CONCLUSIÓN: presentamos las características clínicas, histológicas y de imagen de un osteosarcoma parosteal con componentes de liposarcoma y condrosarcoma de bajo grado.

Visfatin Facilitates VEGF-D-Induced Lymphangiogenesis through Activating HIF-1α and Suppressing miR-2277-3p in Human Chondrosarcoma.

Chondrosarcoma is a malignant bone tumor that arises from abnormalities in cartilaginous tissue and is associated with lung metastases. Lymphangiogenesis plays an essential role in cancer metastasis. Visfatin is an adipokine reported to enhance tumor metastasis, but its relationship with VEGF-D generation and lymphangiogenesis in chondrosarcoma remains undetermined. Our results from clinical samples reveal that VEGF-D levels are markedly higher in chondrosarcoma patients than in normal individuals. Visfatin stimulation promotes VEGF-D-dependent lymphatic endothelial cell lymphangiogenesis. We also found that visfatin induces VEGF-D production by activating HIF-1α and reducing miR-2277-3p generation through the Raf/MEK/ERK signaling cascade. Importantly, visfatin controls chondrosarcoma-related lymphangiogenesis in vivo. Therefore, visfatin is a promising target in the treatment of chondrosarcoma lymphangiogenesis.