Intramuscular mesenchymal chondrosarcoma surrounded by a split fat sign mimicking a benign lesion.

Mesenchymal chondrosarcoma (MCS) is an aggressive malignant mesenchymal tumour of uncertain differentiation. This is rare, accounting for 2%-4% of chondrosarcomas. Its peak incidence is in the second and third decades, though it can occur at any age. These tumours show a widespread distribution, mainly in bone, but with approximately 40% affecting somatic soft tissue. We present a case of MCS arising within the soleus muscle. The lesion was surrounded by a split-fat sign/fatty rind which is a typical feature of peripheral nerve sheath tumours or other benign intramuscular tumours. However, percutaneous biopsy showed MCS. We highlight how perilesional fat is not exclusive to benign intramuscular lesions and, although much less common, can be associated with malignant lesions. This is, to the best of our knowledge, the first reported case of MCS presenting with a split-fat sign at MRI.

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.

Primary intra- and extradural extramedullary mesenchymal chondrosarcoma with isolated punctate calcification: case report and literature review.

BACKGROUND: Mesenchymal chondrosarcoma (MCS) is an ultra-rare, high-grade subtype of chondrosarcoma affecting both bone and soft tissues. Extra-skeletal MCS rarely occurs in intra- and extradural regions. CASE PRESENTATION: We presented a case of intraspinal dumbbell-shaped MCS at the T12-L2 level with isolated punctate calcification in a 19-year-old male complaining of progressive lower back pain. Surgical treatment for removal of the tumor was performed. The postoperative pathological result confirmed MCS. The patient showed symptomatic improvement and follow-up MRI showed no evidence of recurrence or metastasis for nearly 1 year after surgery. CONCLUSIONS: CT and MRI play an important role in differential diagnosis for intraspinal MCS. MCS should be added to the differential diagnosis of intraspinal dumbbell-shaped tumors, especially when radiological examinations reveal punctate calcification in a homogeneous enhanced tumor without dural tail sign. However, the final diagnosis depends on histopathological results. Despite the good prognosis of intraspinal MCS, close follow-up after operation is still necessary.

Bilateral renal metastases from extraskeletal mesenchymal chondrosarcoma of thigh.

Mesenchymal chondrosarcoma (MC) is a rare cartilaginous tumour that occurs in the extraskeletal locations in about one-third of cases. It is aggressive in behaviour and may involve the lower extremities, central nervous system or spine. Mesenchymal tumours are known for distant metastasis; however, metastasis to bilateral kidneys after treatment has not been reported earlier. We present a case of a soft-tissue intramuscular MC of the thigh in a 38-year-old patient which had been surgically excised after neoadjuvant chemotherapy. The patient presented with bilateral dense calcified renal masses after 6 years, which were cytologically proven as MC metastases. In the evaluation of bilateral calcified renal masses in patients with a history of MC, metastasis should be considered.

Rare case report and literature review of intracranial mesenchymal chondrosarcoma.

Intracranial mesenchymal chondrosarcoma (IMC) is a rare primary malignant tumor in the skull, but mostly originates from the abnormal residual chondrocytes in the embryonic period, which grow slowly, and primarily occurs at the junction of the cartilage of the skull base. IMC is difficult to diagnose by preoperative imaging and is easily misdiagnosed. It needs to be differentiated from meningiomas, gliomas, hemangioma, fibroids, etc.; this article introduces a case of primary IMC in a 38-year-old female teacher, and reviews the literature on the diagnosis and treatment of symptoms. The patient suffered from persistent severe headaches without nausea and vomiting. There was no obvious abnormality in the physical examination. Magnetic resonance imaging (MRI) of the head showed a circular space-occupying lesion on the right frontal bone and forehead; the mass was approximately 5.9 cm × 5.2 cm × 5.5 cm, and there was a large edema band surrounding it. The space-occupying effect was obvious; bilateral ventricles were compressed, and on the right side, the midline structure was shifted to the left. The patient was initially diagnosed with simple meningioma. After admission, the right frontal lobe meningioma was resected under general anesthesia, and the tumor tissue was completely removed in blocks. The postoperative pathology report stated: malignant tumor of the right frontal lobe; consider mesenchymal chondrosarcoma. Following a difficult pathological consultation at the Provincial Medical Association, the tumor was found to be consistent with mesenchymal chondrosarcoma. Intracranial chondrosarcoma is a very rare malignant tumor. Other intracranial masses, such as meningioma and glioma, should be distinguished through differential diagnosis. At present, more attention is paid to surgical intervention and combined radiotherapy and chemotherapy for the treatment of IMC, which should also be the future treatment option.

[Mesenchymal chondrosarcoma in central nervous system: a clinicopathological analysis].

Objective: To investigate the clinicopathological features of central nervous system (CNS) mesenchymal chondrosarcoma (MCS). Methods: Nine cases of CNS MCS were collected at the First Affiliated Hospital of Fujian Medical University from September 2010 to September 2020. The clinical,imaging,histopathological and immunohistochemical features were reviewed. NCOA2 gene rearrangement was evaluated by fluorescence in situ hybridization (FISH). Results: There were three male and six female patients, with age range of 1 to 59 years (median 31 years). Six cases were intracranial and three cases were intraspinal, and the tumors showed dural attachment. They were often diagnosed as meningioma basing on preoperative imaging. Microscopically, the tumors showed a characteristic biphasic histologic pattern composed of undifferentiated mesenchymal small cells and well-differentiated hyaline cartilage islands. The small cells area were positive for SOX9 (9/9), CD99 (8/9), and without BRG1 and INI1 deletion. The cartilaginous component expressed SOX9 (9/9) and S-100 protein (8/9). NCOA2 gene break apart signal was identified in five cases (5/5). Eight patients were followed up for 4-124 months. Three patients (3/8) had recurrences within one year and two patients died of the tumor. Conclusions: CNS MCS is an extremely rare malignant neoplasm with a propensity to dural involvement. Preoperative imaging has low diagnostic accuracy. CNS MCS should be differentiated from other CNS small round cell tumors and chondrosarcoma. FISH detection of NCOA2 gene rearrangement will assist the diagnosis of MCS.

Intravascular Mesenchymal Chondrosarcoma of the Femoral Vein: A Case Report.

CASE: A 30-year-old man presented with progressive lower right extremity pain and swelling, initially diagnosed as a deep venous thrombosis. He returned 18 months later after 2 episodes of gross hemoptysis, with chest computed tomography angiography findings concerning for tumor thrombus in the left pulmonary artery. Subsequent advanced imaging showed a lesion arising from his right femoral vein, which open biopsy revealed to be a primary intravascular mesenchymal chondrosarcoma. He underwent medical therapy, with improvement of pain and swelling and successful return to work. CONCLUSION: Mesenchymal chondrosarcoma is a rare pathology, and its intravascular origin makes this case extraordinarily uncommon.

Mesenchymal Chondrosarcoma in the Maxilla: A Case Report and Literature Review.

Mesenchymal chondrosarcoma is a rare high-grade variant of chondrosarcoma distinguished by its aggressive nature. Molecular studies aid in establishing the diagnosis. We present a case report of mesenchymal chondrosarcoma in the maxilla of a 39-year-old male patient and a literature review of 42 gnathic cases of mesenchymal chondrosarcoma with a discussion of clinical, imaging, microscopic, immunohistochemical, and molecular features.

Mesenchymal chondrosarcoma of the orbit masquerading as a hemophilic pseudotumor.

An 11-year-old boy presented with a lesion of the right orbit that was thought to be a hemophilic pseudotumor. Excisional biopsy revealed an unexpected diagnosis of mesenchymal chondrosarcoma. Both mesenchymal chondrosarcoma and hemophilic pseudotumor of the orbit are exceedingly rare. To the best of our knowledge, this is the first reported case of orbital mesenchymal chondrosarcoma masquerading as hemophilic pseudotumor.

Mesenchymal chondrosarcoma: imaging features and clinical findings.

OBJECTIVE: To describe imaging and clinical features of primary mesenchymal chondrosarcoma (MCS) and evaluate for presence of a distinct biphasic pattern on imaging. MATERIAL AND METHODS: Patients with a pathologic diagnosis of MCS were identified along with imaging of their primary tumor. Size, location, appearance (lytic, sclerotic, or mixed), presence, extent and distribution of calcifications, cortical destruction, soft tissue extension, periosteal reaction, contrast enhancement, and radiotracer uptake were recorded. The presence of T2-hyperintense tumor lobules on MRI and a biphasic morphology (distinct calcified and non-calcified components) on CT were assessed. Presence and location of metastases were documented. RESULTS: Twenty-three patients (mean age 28.0 ± 13.8 years) were reviewed (13 skeletal, 10 extraskeletal). Overall mean tumor size was 10.2 ± 7.2 cm, 7.1 ± 7.3 cm in non-metastatic and 13.2 ± 5.9 cm (p = 0.004) in metastatic cases. Locations were extremities (n = 11), head/neck (n = 4), chest wall (n = 4), pelvis (n = 3), and retroperitoneum (n = 1). Skeletal MCS were aggressive mixed lytic and sclerotic (n = 8), purely lytic (n = 4), or juxtacortical (n = 1) lesions with cortical destruction and soft tissue extension. Chondroid calcifications were common (80%). On MRI, the presence of T2-hyperintense lobules was seen in 35%. A biphasic morphology on imaging was seen in 30%. Metastases were common (52%) with the most common site being the lungs (75%). All tumors were hypermetabolic with a mean SUVmax of 14.3 (5.6-34) on PET/CT. CONCLUSION: Skeletal MCS commonly present as aggressive lytic bone lesions with chondroid calcifications. A biphasic morphology was seen in one-third of cases. Metastases were common at initial presentation and more commonly seen with larger tumors.

Heavily calcified parapharyngeal space mesenchymal chondrosarcoma: Imaging and pathological findings and a review of the literature.

Parapharyngeal space (PPS) masses are relatively rare lesions of the head and neck, and account for 0.5-1.5% of head and neck lesions. The most common lesion to occur in the PPS is a benign salivary neoplasm, typically pleomorphic adenoma either from the deep parotid or from ectopic parotid tissue rests within the PPS. A calcified or ossified mass in this location is exceedingly rare, but a calcified variant of pleomorphic adenoma has been reported. In this study, we present a patient with a heavily calcified PPS mesenchymal chondrosarcoma with an unusual presentation. We discuss the imaging and pathologic findings followed by a review of the current literature.

Intracranial extra-axial mesenchymal chondrosarcoma in a 16-month-old patient with a literature review of pediatric patients.

Mesenchymal chondrosarcoma is a rare high-grade malignant subtype of chondrosarcoma that is characterized by undifferentiated, round, or spindled mesenchymal cells, interspersed with islands of hyaline cartilage. We report a primary intracranial extra-axial mesenchymal chondrosarcoma in a 16-month-old patient with a review of the literature focusing on intracranial extra-axial MCs with or without skull involvement in pediatric patients, including differential diagnosis. The patient was admitted with a swelling in the right temporooccipital region. There was intracranial extra-dural extension of the mass, which abuts the neural parenchyma without any invasion. A complete tumor resection was performed. Pathological diagnosis was mesenchymal chondrosarcoma. The patient was free of symptoms after surgery.

Paediatric High-Grade Intracranial Mesenchymal Chondrosarcoma: A Case Report with 6 Years of Follow-Up without Recurrence.

INTRODUCTION: Intracranial mesenchymal chondrosarcoma (MSC) is an extremely rare tumour that constitutes only 0.015% of all central nervous system tumours. These tumours usually originate from skull base synchondrosis and are often observed in young adults during their second and third decades of life. Despite the absence of a consensus regarding adjuvant radiotherapy, radical excision remains crucial for the prognosis of MSC. CASE PRESENTATION: We herein present the case of a young male patient with intracranial MSC, a malignant tumour, for which no consensus regarding its treatment has yet been established. The patient underwent radical excision followed by adjuvant radiotherapy. Histological analysis revealed a poorly differentiated tumour containing necrotic areas. Notably, no signs of recurrence had been observed after 6 years. CONCLUSION: The absence of recurrence over a long follow-up duration suggests the importance of radical excision and adjuvant radiotherapy.

Metastasectomy of left atrial mesenchymal chondrosarcoma.

Metastasis of chondrosarcoma of skeletal origin to the heart is uncommonly reported in the literature, with the majority of cases involving right atrial metastases. Surgical resection remains the mainstay of treatment, and the literature has shown improved median survival with this form of therapy, possibly by reducing thromboembolic risk in this patient population. We report the case of a patient with metastatic mesenchymal chondrosarcoma of the left atrium who underwent resection, following a lack of response to anticoagulation therapy. This is the first report of surgical resection of left atrial metastatic disease prior to the onset of thromboembolic sequelae.

Surgical treatment of metastatic mesenchymal chondrosarcoma to the spine: A case report.

INTRODUCTION: Metastatic mesenchymal chondrosarcoma of the spine is a highly unusual disease without standard curative managements yet. The objective of this case report is to present a very rare case of metastatic chondrosarcoma to the spine successfully operated by surgical treatment. The management of these unique cases has yet to be well-documented. PATIENT CONCERNS: A 34-year-old woman presented with a 4-month history of continuous and progressive back pain and a 1-month history of radiating pain of bilateral lower extremities. The patient, who had been diagnosed of mesenchymal chondrosarcoma of maxillary sinus for 3 years, received surgical treatment of palliative endoscopic-assisted total left maxillary resection via mini Caldwell-Luc approach, and palliative enlarged resection due to the progress of residual lesions, followed by no adjuvant therapy. Multiple lytic, expanding lesions of the spine and paraspinal region with severe epidural spinal cord compression was identified. DIAGNOSIS: CT, MRI and bone scan of spine showed spinal cord compression secondary to the epidural component of the metastatic lesions. Post-operative pathology confirmed the diagnosis of metastatic spinal mesenchymal chondrosarcomas. INTERVENTIONS: The patient underwent posterior spinal canal decompression, resection of T12 and L3 lesions, internal fixation of T11-L5 pedicles, and cement augmentation of T12 and L3. OUTCOMES: The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 1-year follow-up visit. There were no complications associated with the spinal surgery during the follow-up period. CONCLUSION: Metastatic spinal mesenchymal chondrosarcoma, although rare, should be part of the differential diagnosis when the patient presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression and total resection of the metastatic chondrosarcoma when the tumor has caused neurological deficits or other severe symptoms. Osteoplasty by cement augmentation is also a good choice for surgical treatment in some patients.

Mesenchymal chondrosarcoma of maxilla in paediatric patient.

Chondrosarcoma (CS) is a malignant tumour of long and flat bone characterised by the formation of cartilage. Mesenchymal chondrosarcoma (MCS) is a rare subtype of CS that is more aggressive and may lead to erroneous diagnosis in a limited biopsy. The diagnosis is mainly based on the histopathological appearance of biphasic pattern of undifferentiated small round cells separated by islands of well-differentiated hyaline cartilage. We report a case of 13-year-old boy who initially presented with gum swelling and the biopsy result suggested a benign fibrous lesion. Following an extensive lesion shown in radiologic findings, the tumour excision was done and finally was diagnosed as an MCS of the maxilla. The patient was given postoperative chemotherapy (EURO-EWING 99 regimen), and now on regular follow-up for monitoring of local recurrence or tumour metastasis.

Metastasis from Intracranial Mesenchymal Chondrosarcoma: Report of a Rare Case.

Chondrosarcoma is a rare malignant tumor originating from cartilaginous tissue with a tendency to localize in the epiphysis of long and pelvic bones. Only 7% of all chondrosarcomas originate in the craniocervical region. Metastasis from intracranial chondrosarcoma is extremely rare with only two previously reported cases. We report on a young patient with intracranial chondrosarcoma who presented with extracranial metastasis 2 years after surgical excision of the primary lesion. Gross total excision combined with radiotherapy so far has led to a favorable outcome.

The Differences Between Intracranial Mesenchymal Chondrosarcoma and Conventional Chondrosarcoma in Clinical Features and Outcomes.

OBJECTIVE: To report differences in clinical features and outcomes between intracranial mesenchymal chondrosarcoma (MCS) and conventional chondrosarcoma (CCS). METHODS: Clinical data of patients with primary intracranial MCS and CCS were retrospectively extracted and analyzed to compare differences between MCS and CCS. RESULTS: Seventy-four patients with intracranial chondrosarcoma (61 cases with MCS and 13 cases with CCS) were included. Compared with patients with CCS, patients with MCS presented at a younger mean age (21.1 years vs. 34.5 years, P < 0.001) and had a poor mean preoperative Karnofsky performance scale score (64.6 vs. 77.8, P = 0.014). Compared with CCS, MCS was less often located in the skull base (38.5% vs. 96.7%, P < 0.001) and had a larger tumor volume (87.8 cm3 vs. 26.7 cm3, P < 0.001). Rates of gross total resection in MCS and CCS subgroups were 41.1% (n = 25) and 46.2% (n = 6), respectively; rates of adjuvant radiotherapy postoperatively were 44.2% (n = 27) and 46.2% (n = 6), respectively. After mean follow-up of 41.7 months, 1-year, 3-year, and 5-year overall survival and progression-free survival of MCS were significantly shorter than overall survival and progression-free survival of CCS. Multivariate analysis revealed that tumor pathology and extent of surgery were independent predictors for tumor recurrence. CONCLUSIONS: Clinical features of MCS are quite different from CCS. Treatment strategies used for CCS do not yield satisfactory outcomes for MCS. Treatment of MCS should be aggressive and individualized.

Mesenchymal chondrosarcoma of the orbit: imaging features of CT and MRI.

OBJECTIVE:: Mesenchymal chondrosarcoma (MCS) of the orbit is a rare and aggressive form of chondrosarcoma. The purpose of this study was to retrospectively identify the imaging features of mesenchymal chondrosarcoma of the orbit. METHODS:: This study included five patients with histologically confirmed MCS of the orbit who had undergone either CT, MRI, or both. Images were evaluated for the following: location, size, margin, CT density and presence or absence of calcification and/or ossification, MRI findings including dynamic contrast-enhancement and time-intensity curves. RESULTS:: CT was performed in four of the five patients, and all four (100%) demonstrated calcification and ossification of the mass. MRI was performed in all five patients. In two patients (40%), the mass demonstrated areas of hyperintensity on T1 weighted images. CONCLUSION:: The presence of a well-defined, orbital mass with calcification and ossification on CT and, marked heterogenous enhancement and a rapid-washout pattern on dynamic MRI indicate a high probability of MCS of the orbit. In addition, MCS of the orbit can demonstrate areas of hyperintensity on T1 weighted images, representing bone marrow fat tissue of ossification. ADVANCES IN KNOWLEDGE:: MCS of the orbit is a highly malignant tumor, and early diagnosis by imaging is important. Radiologists should be aware of the imaging features of MCS of the orbit.