Xu H, Shao M, Sun H, Li S
Primary mesenchymal chondrosarcoma of the kidney with synchronous implant and infiltrating urothelial carcinoma of the ureter.
Diagn Pathol. 2012; 7:125 [PubMed] Free Access to Full Article

Primary mesenchymal chondrosarcoma of the kidney is rare, and it shows distinct undifferentiated tumor cells and well differentiated cartilagenous components. Also assident infiltrating urothelial carcinoma of the ureter is an extremely rare cancer. We report a case of primary mesenchymal chondrosarcoma occurring in the left kidney with an ipsilateral and distinct distal ureteric implant, and a coexisting infiltrating urothelial carcinoma of the ureter in a 64-year-old man. Histopathological examination and immunohistochemical studuies showed the classic features of mesenchymal chondrosarcoma in kidney, as well as a few infiltrating urothelial in ureter. Multitarget fluorescence in situ hybridization (FISH) suggested that the development of the urothelial carcinoma in the ureter may be triggered or induced by the chondrosarcoma component. The patient died 2 month after left nephro-ureterectomy. This is the first reported case of a primary mesenchymal chondrosarcoma of the kidney with coexisting infiltrating urothelial carcinoma of the ureter. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1522835667751019.

Kan Z, Li H, Zhang J, You C
Intracranial mesenchymal chondrosarcoma: case report and literature review.
Br J Neurosurg. 2012; 26(6):912-4 [PubMed]

BACKGROUND: Mesenchymal chondrosarcoma is a very rare malignant cartilaginous forming tumour in central nervous system (CNS), which is rarely encountered in clinical practice and generally occurs in young adults. This article describes a case of primary intracranial mesenchymal chondrosarcoma in a 31-year-old woman and reviews the literature on its manifestations and management.
CASE REPORT: This patient had suffered from severe headache, intermittent nausea and vomiting for 1 week. Systemic examination was unremarkable. Magnetic resonance imaging (MRI) demonstrated a giant, heterogeneous, intensely enhancing mass of 6 × 5 × 4 cm, occupying the bilateral frontal and based on the anterior falx cerebri, which was initially thought to be a simply meningioma. The patient underwent a bicoronal craniotomy and gross total resection of the tumour. Pathologic examination revealed the mesenchymal chondrosarcoma.
CONCLUSION: Intracranial mesenchymal chondrosarcoma is an extreme rare neoplasm, which should be considered in the differential diagnosis of intracranial mass like a meningioma. We emphasize the importance of surgical intervention and combination of microsurgical resection and radiotherapy, it should be the therapeutical choice of the future.

Chen Y, Wang X, Guo L, et al.
Radiological features and pathology of extraskeletal mesenchymal chondrosarcoma.
Clin Imaging. 2012 Jul-Aug; 36(4):365-70 [PubMed]

OBJECTIVE: The objective of this study was to elucidate the imaging and pathological features of extraskeletal mesenchymal chondrosarcomas (EMCs).
METHODS: Imaging findings of eight EMC cases were retrospectively analyzed.
RESULTS: Soft tissue masses with different patterns of mineralization were found in five cases on computed tomographic scans. On magnetic resonance images, peripherally located EMCs demonstrated mixed signal intensity on T2-weighted images and heterogeneous enhancement with both calcified and noncalcified areas.
CONCLUSION: EMCs exhibited several characteristic imaging features, which when used in combination with the mineralization pattern, enhancement of the calcified area, and signal intensity feature might have diagnostic value for this rare tumor.

Meijer D, de Jong D, Pansuriya TC, et al.
Genetic characterization of mesenchymal, clear cell, and dedifferentiated chondrosarcoma.
Genes Chromosomes Cancer. 2012; 51(10):899-909 [PubMed]

Clear cell, mesenchymal, and dedifferentiated chondrosarcoma are rare, cartilaginous tumors with limited treatment options other than surgery. Conventional chondrosarcomas have been extensively studied at the genetic level, but for rare chondrosarcoma subtypes, this is merely restricted to case reports. Information on the genetics of rare chondrosarcomas may provide insight into the etiology of these specific disease subtypes and possible alternative treatment strategies. Therefore, the aim of this study was to genetically characterize this subset of rare tumors. Using array CGH, we gathered genomic information of 30 rare cartilaginous tumors. In addition, we constructed tissue microarrays with 2 mm cores of 23 clear cell, 23 mesenchymal, and 45 dedifferentiated chondrosarcomas, in triplicate. Using immunohistochemistry, we investigated expression of R132H IDH1, and p53 and retinoblastoma pathways. Results were verified and further investigated with a methylation assay and MLPA for CDKN2A/p16, and IDH1/2, and TP53 mutation analysis. Array-CGH showed numerous genomic alterations in all subtypes. However, only a limited number of recurrent alterations were detected, none of which seemed to be associated with the subtypes. The IDH1/2, p53, and retinoblastoma pathways were affected in 0, 9, and 95% of clear cell chondrosarcomas, in 0, 39, and 70% in mesenchymal chondrosarcomas, and in 50, 59, and 85% of dedifferentiated chondrosarcomas, respectively. Our results suggest an important role for the retinoblastoma pathway in all three rare chondrosarcoma subtypes investigated.

Vergeer RA, Vink R, Avenarius JK, Driesse MJ
A 71-year-old woman with an intracranial dural-based mesenchymal chondrosarcoma.
J Clin Neurosci. 2012; 19(8):1170-1 [PubMed]

Intracranial mesenchymal chondrosarcoma is a rare, high-grade malignancy with the highest prevalence in young adults. Because of its rarity, most data regarding survival are limited to case studies and small series. We present a 71-year-old woman with an intracranial dural based mesenchymal chondrosarcoma located in the anterior skull base, to our knowledge the oldest patient reported with this tumor.

Obuchowicz AK, Szumera-Ciećkiewicz A, Ptaszyński K, et al.
Intraspinal mesenchymal chondrosarcoma in a 14-year-old patient: diagnostic and therapeutic problems in relation to the review of literature.
J Pediatr Hematol Oncol. 2012; 34(5):e188-92 [PubMed]

Mesenchymal chondrosarcoma (MC) is an infrequent, highly malignant neoplasm of the soft tissues and bone. It is very rare in the pediatric age group, especially in the intraspinal location. Only 24 cases have been reported to date. The authors present a case of a 14-year-old boy with an intraspinal MC who died of the disease 50 months from the initial diagnosis and after the third local recurrence. The patient was treated with a combination of chemotherapy, radiotherapy, and surgery. The authors review the clinical presentation, diagnostics, and the efficacy of treatment of pediatric patients with MC reported in the literature from 1978 to 2010.

Szumera-Ciećkiewicz A, Ptaszyński K, Grabowski P, et al.
Quiz. Correct answer to the quiz. Check your diagnosis. Mesenchymal chondrosarcoma of the orbit: two cases and a brief review of the literature.
Pol J Pathol. 2012; 63(1):80-4 [PubMed]

Mesenchymal chondrosarcoma (MChS) is a rare, high-grade malignant tumor which occurs both in the bone and soft tissue. The extraskeletal location comprises one third of all MChS and in review of the up-to-date literature, about 30 cases of the orbital involvement were found. The authors present clinical, radiological and pathological findings of two cases of MChS of the orbit occurring in young adult females: primary extraskeletal MChS of the orbit and skeletal MChS of the ethmomaxillary complex with secondary orbit involvement. The histopathological examination revealed a characteristic biphasic pattern composed of small round to spindle-shaped cells, mimicking Ewing sarcoma family of tumors, with areas of a haemangiopericytoma-like pattern and admixed cartilage foci. One of the patients had local recurrence 3 years after initial surgical removal. Subsequently, she underwent enucleation followed by chemotherapy. The other patient had a biopsy and debulking resection of the tumor and started chemotherapy. Ten months follow-up of this patient show no evidence of metastasis.

Patel R, Mukherjee B
Mesenchymal chondrosarcoma of the orbit.
Orbit. 2012; 31(2):126-8 [PubMed]

PURPOSE: To report a case of mesenchymal chondrosarcoma of the orbit and describe its clinical features, radiological findings and management.
METHOD: Interventional case report.
RESULT: A 50 year old man presented with right sided proptosis of 3 months duration. CT scan showed well circumscribed lobulated extraconal mass lesion in the inferotemporal qaudrant with specked calcification within. Patient underwent excisional biospsy with excision of mass lesion in toto. Histopathological examination was suggestive of mesenchymal chondrosarcoma of orbit. Post operatively patient was advised radiotherapy.
CONCLUSION: Orbital mesenchymal chondrosarcoma is a rare tumor characterized by undifferentiated mesenchymal cells with islands of mature hyaline cartilage. Multimodality treatment (surgery, chemotherapy, and radiotherapy) may lead to long-term survival.

Shakked RJ, Geller DS, Gorlick R, Dorfman HD
Mesenchymal chondrosarcoma: clinicopathologic study of 20 cases.
Arch Pathol Lab Med. 2012; 136(1):61-75 [PubMed]

CONTEXT: Mesenchymal chondrosarcoma is a rare, high-grade malignancy of bone or soft tissue with a unique, biphasic histology and poor prognosis. Because of its rarity and variable length of disease-free survival, the natural history of the disease remains poorly understood.
OBJECTIVE: To present clinical, radiographic, and histopathologic features of mesenchymal chondrosarcoma from one of the largest case series collected by a single, senior-level bone pathologist.
DESIGN: Twenty cases were reviewed in consultations spanning 45 years.
RESULTS: Eighteen tumors (90%) originated in bone, and 2 tumors (10%) were of extraskeletal origin. Of the skeletal tumors, locations included craniofacial bones (n  =  9; 50%), ribs and chest wall (n  =  4; 22%), sacrum and spinal elements (n  =  3; 17%), and lower extremities (n  =  2; 11%), whereas soft tissue tumors were located about the scapula (n  =  1; 50%) and lower extremity (n  =  1; 50%). Plain radiographs demonstrated calcified, osteolytic lesions with extraosseous extension. Typical histologic features were identified consisting of small, round or spindled cells, interspersed with hyaline cartilage islands. Seventeen patients (85%) were treated surgically, and 8 patients (40%) received adjuvant treatment. Seven patients (35%) were living at last follow-up, 1.8 to 12.5 years after diagnosis, and 8 patients (40%) died between 1.2 and 21.8 years after diagnosis.
CONCLUSIONS: Mesenchymal chondrosarcoma presents multiple challenges. Diagnostic pitfalls include inadequate biopsy samples, which may result in sample error. Sox9 has been proposed as a unique marker for mesenchymal chondrosarcoma which may improve diagnostic specificity. Treatment and prognosis vary considerably. Patients who receive surgery and chemotherapy seem to fare better. Multicenter studies with higher sample numbers may improve our understanding of this malignancy.

Yang BT, Wang YZ, Wang XY, Wang ZC
Mesenchymal chondrosarcoma of the orbit: CT and MRI findings.
Clin Radiol. 2012; 67(4):346-51 [PubMed]

AIM: To describe the computed tomography (CT) and magnetic resonance imaging (MRI) features of orbital mesenchymal chondrosarcomas (MCSs).
MATERIALS AND METHODS: Six patients with histology-confirmed MCSs of the orbit were retrospectively reviewed. All six patients underwent CT and MRI. Imaging studies were evaluated for the following: (a) tumour location, (b) configuration, size, and margin, (c) CT attenuation and MRI signal intensity, and (d) secondary manifestations. Additionally, the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI were analysed in five patients.
RESULTS: Two MCSs arose in the right orbit and four in the left orbit. Five MCSs were located in the retrobulbar intraconal space and one in the extraconal space. All the lesions displayed a lobulate configuration and had a well-defined margin. The mean maximum diameter was 25.8 mm (range 15-36 mm). On unenhanced CT, the lesions appeared isodense to grey matter in six patients, with calcifications in five. Two patients showed inhomogeneous, moderate enhancement on enhanced CT. Six MCSs appeared isointense on T1-weighted imaging and heterogeneously isointense on T2-weighted imaging. The lesions showed significantly heterogeneous contrast enhancement. Five patients had DCE MRI and the TICs showed a rapidly enhancing and rapid washout pattern (type III). The following features were also detected: compression of the extra-ocular muscle (six patients, 100%); displacement of the optic nerve (five patients, 83.3%); and encasing globe (three patients, 50%).
CONCLUSIONS: A well-defined, lobulate orbital mass with calcification on CT and, marked heterogeneous enhancement and type III TIC on MRI are highly suspicious of orbital MCSs.

Wang L, Motoi T, Khanin R, et al.
Identification of a novel, recurrent HEY1-NCOA2 fusion in mesenchymal chondrosarcoma based on a genome-wide screen of exon-level expression data.
Genes Chromosomes Cancer. 2012; 51(2):127-39 [PubMed] Free Access to Full Article

Cancer gene fusions that encode a chimeric protein are often characterized by an intragenic discontinuity in the RNA\expression levels of the exons that are 5' or 3' to the fusion point in one or both of the fusion partners due to differences in the levels of activation of their respective promoters. Based on this, we developed an unbiased, genome-wide bioinformatic screen for gene fusions using Affymetrix Exon array expression data. Using a training set of 46 samples with different known gene fusions, we developed a data analysis pipeline, the "Fusion Score (FS) model", to score and rank genes for intragenic changes in expression. In a separate discovery set of 41 tumor samples with possible unknown gene fusions, the FS model generated a list of 552 candidate genes. The transcription factor gene NCOA2 was one of the candidates identified in a mesenchymal chondrosarcoma. A novel HEY1-NCOA2 fusion was identified by 5' RACE, representing an in-frame fusion of HEY1 exon 4 to NCOA2 exon 13. RT-PCR or FISH evidence of this HEY1-NCOA2 fusion was present in all additional mesenchymal chondrosarcomas tested with a definitive histologic diagnosis and adequate material for analysis (n = 9) but was absent in 15 samples of other subtypes of chondrosarcomas. We also identified a NUP107-LGR5 fusion in a dedifferentiated liposarcoma but analysis of 17 additional samples did not confirm it as a recurrent event in this sarcoma type. The novel HEY1-NCOA2 fusion appears to be the defining and diagnostic gene fusion in mesenchymal chondrosarcomas.

Vij M, Krishnani N, Agrawal V, et al.
Cytomorphology of intraparenchymal mesenchymal chondrosarcoma in frontal lobe: report of a case.
Diagn Cytopathol. 2011; 39(11):837-42 [PubMed]

lntracranial mesenchymal chondrosarcomas (MC) and especially those that originate in brain parenchyma, are rare. A diagnosis of MC can be challenging to make on squash cytology. We describe cytomoprhology of solid cystic extraskeletal intraparenchymal MC in a 22-year-old male. The tumor was located in left frontal lobe. Cytology results demonstrated oval-to-spindled cells with high nuclear-to-cytoplasmic ratios. Cells showed perivascular arrangement. Small foci of basophilic extracellular matrix with scattered malignant chondroid component were also seen. Histologic examination of lesion demonstrated biphasic tumor, with prominent small cell population and focal atypical cartilage. Whole body survey of the patient was performed and no other extracrainal lesion was identified in the patient. The patient developed recurrence within 2 months. To the best of authors' knowledge this is the first case report describing cytomorphology of intraparenchymal MC. We discuss the differential diagnosis in light of relevant literature.

Rossetto A, Saccomano E, Zompicchiatti A, et al.
Mesenchymal chondrosarcoma of the spleen: report of a case.
Tumori. 2011 Jul-Aug; 97(4):e10-5 [PubMed]

BACKGROUND: Chondrosarcoma is a malignant tumor of chondrogenic origin and the mesenchymal type is a very rare finding. Mesenchymal chondrosarcoma tends to develop mostly in the skeleton but may also occur as a primary tumor in periosteal nervous and muscular tissues, the anterior cerebral falx, meninges, brain, maxillary sinus, eyelid, thyroid, pleura and mediastinum, while in the abdomen the most frequent locations are the kidney, retroperitoneum and even the perineum and the anogenital area. Apparently, the only splenic mesenchymal chondrosarcoma in the literature occurred in a dog.
METHODS AND STUDY DESIGN: Our paper reports the case of a patient who had a diagnosis of mesenchymal chondrosarcoma of the spleen. Results. We adopted surgery as the main therapeutic procedure without achieving complete recovery but preserving a good quality of life for our patient, minimizing the repercussions of the disease on her working and relational life.
CONCLUSIONS: The absence of important or invalidating symptoms and the persistence of good general conditions before and after each surgical operation encouraged us to adopt the surgical option as the most rational.

Krishnamurthy A, Vaidhyanathan A, Srinivas S, Majhi U
A fatal case of mesenchymal chondrosarcoma of the mandible.
J Cancer Res Ther. 2011 Apr-Jun; 7(2):192-4 [PubMed]

A 34-year-old man presented with an expansile, erosive tumor involving the left side of the mandible, with secondary invasion into the maxilla, measuring 13 Χ 7 cm. Microscopic analysis revealed a malignant small round cell neoplasm with focal cartilaginous differentiation. Immunohistochemical analysis revealed positivity for vimentin, NSE and CD99 with primitive small round cells, and S100 positivity with neoplastic chondrocytes. To the best of our knowledge, this is perhaps the largest reported case of mesenchymal chondrosarcoma of the maxillofacial region. Diagnosed as inoperable, he was treated with radiation and chemotherapy only to die within a few months.

Cheim AP, Queiroz TL, Alencar WM, et al.
Mesenchymal chondrosarcoma in the mandible: report of a case with cytological findings.
J Oral Sci. 2011; 53(2):245-7 [PubMed]

Mesenchymal chondrosarcoma is an infrequent malignancy of bone and soft tissue, characterized by its peculiar bimorphic histological pattern. The use of fine-needle aspiration (FNA) in the diagnosis of bone tumors is controversial. A 31-year-old woman presented with a mandibular lesion detected on routine examination for orthodontic treatment. Radiography revealed an ill-defined mixed radiolucency in the premolar region of the right mandible with invasive characteristics such as root resorption and widening of the periodontal ligament space of neighboring teeth. Blood clots obtained at FNA were fixed in formalin and exhibited spindle cells surrounding islands of pleomorphic chondroblasts against a bloody background. Histopathologically, clusters of spindle cells juxtaposed with mesenchymal tissue were detected, with a large hemangiopericytomatous component. In the present case, cytological findings combined with clinical and radiological data provided valuable information in establishing the diagnosis of malignancy and in planning further procedures and treatment.

Lin L, Varikatt W, Dexter M, Ng T
Diagnostic pitfall in the diagnosis of mesenchymal chondrosarcoma arising in the central nervous system.
Neuropathology. 2012; 32(1):82-90 [PubMed]

Mesenchymal chondrosarcoma is a rare aggressive neoplasm typically affecting the bones of young adults. It may also arise in somatic soft tissue, the CNS and other organs. It has a characteristic biphasic histological pattern composed of highly undifferentiated small round cells and islands of well-differentiated hyaline cartilage. We report a case of mesenchymal chondrosarcoma arising from the right tentorium cerebelli in a 21-year-old woman with symptoms relating to mass effect. Histological examination demonstrated a purely small round cell appearance in a specimen obtained during partial resection at an outside institution, leading to an erroneous diagnosis of Ewing sarcoma/primitive neuroectodermal tumor (PNET). The diagnosis of mesenchymal chondrosarcoma was made only after tissue obtained during a definitive complete macroscopic removal involving the regional tentorium cerebelli, transverse and sigmoid dural venous sinuses which showed a prominent cartilaginous component. We discuss the features of mesenchymal chondrosarcoma arising in the CNS, the important differential diagnoses of small round-cell tumors within the CNS, and the differentiating features of mesenchymal chondrosarcoma from Ewing sarcoma/PNET, medulloblastoma, hemangiopericytoma, monophasic synovial sarcoma and atypical teratoid/rhabdoid tumour.

Jain A, Safaya R, Jagan C, Sharma SK
Extraskeletal mesenchymal chondrosarcoma of the pleura: report of a rare case.
Indian J Pathol Microbiol. 2011 Jan-Mar; 54(1):144-6 [PubMed]

Mesenchymal chondrosarcoma is a rare aggressive variant of chondrosarcoma that frequently occurs in extraskeletal location. A 28-year-old female presented with a history of dyspnea and fever and succumbed to her illness before a conclusive diagnosis was established. An autopsy performed revealed the presence of an extraskeletal mesenchymal chondrosarcoma (ESMC) involving the pleura. Only one case of ESMC of the pleura has been reported previously. Herein, we report the second case of ESMC of the pleura.

Lee AF, Hayes MM, Lebrun D, et al.
FLI-1 distinguishes Ewing sarcoma from small cell osteosarcoma and mesenchymal chondrosarcoma.
Appl Immunohistochem Mol Morphol. 2011; 19(3):233-8 [PubMed]

Small cell osteosarcoma and mesenchymal chondrosarcoma are 2 primary bone tumors with a small round blue cell component, which can mimic the appearance of Ewing sarcoma. Distinguishing these tumors from each other on biopsy material is important clinically, as optimal therapy differs according to the tumor type. However, separating these entities on morphology alone can be challenging. FLI-1 has been described to be a useful marker for Ewing sarcoma, particularly when hematolymphoid markers are negative. In small cell osteosarcoma and mesenchymal chondrosarcoma, the FLI-1 staining pattern has not been adequately characterized. Using a monoclonal FLI-1 antibody, nuclear immunoreactivity in tumor cells was evaluated in 10 small cell osteosarcomas, 10 mesenchymal chondrosarcomas, and 8 Ewing sarcomas, together with a number of other small, round, blue cell tumors. None of the small cell osteosarcomas or mesenchymal chondrosarcomas exhibited FLI-1 staining in the tumor cells, in contrast to the positive nuclear FLI-1 staining in the stromal endothelial cells. In comparison, 6 of the 8 Ewing sarcomas showed moderate-to-strong nuclear FLI-1 staining of the tumor cells in addition to strong staining of the stromal endothelial cell nuclei. With the exception of lymphoblastic lymphomas, FLI-1 positivity was not seen in the other small round blue cell tumors examined. These findings show that, in contrast to Ewing sarcoma, small cell osteosarcoma and mesenchymal chondrosarcoma lack FLI-1 immunoreactivity. FLI-1 is therefore useful in the differential diagnosis of small round blue cell tumors of the bone.

Bean SM, Baker A, Eloubeidi M, et al.
Endoscopic ultrasound-guided fine-needle aspiration of intrathoracic and intra-abdominal spindle cell and mesenchymal lesions.
Cancer Cytopathol. 2011; 119(1):37-48 [PubMed]

BACKGROUND: The role of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in the evaluation of spindle cell and mesenchymal lesions is unclear. This study reviews the use of EUS-FNA in diagnosing intrathoracic and intra-abdominal spindle and mesenchymal cell lesions at an academic institution.
METHODS: All EUS-FNA specimens with a significant spindle or mesenchymal cell component were retrieved. Follow-up was comprised of clinical correlation, chart review, or evaluation of subsequent tissue specimens, including FNAs, biopsies, and/or surgical resections. Lesions were categorized as either inflammatory/reactive or neoplastic.
RESULTS: Forty-four EUS-FNA specimens were retrieved from 39 patients (21 men and 18 women with a median age of 61 years [range, 20-88 years]). Anatomic sites included 19 lymph node specimens, 15 gastrointestinal tract specimens, 7 pancreatic specimens, and 4 other anatomic site specimens. Twenty-two cases were inflammatory/reactive lesions, including 17 granulomatous lesions and 5 cases of chronic pancreatitis. Twenty-two cases were neoplastic, including 14 gastrointestinal stromal tumors, 2 smooth muscle tumors, 2 sarcomatoid carcinomas, 2 melanomas, 1 sarcoma, and 1 solitary fibrous tumor. A specific cytologic diagnosis was rendered in 30 cases (81%). Immunocytochemistry was performed on 21 neoplastic cases and contributed to the differential diagnosis in 18 cases. No false-positive findings were encountered. Three false-negative results were identified and were attributed to sampling error.
CONCLUSIONS: Spindle cell neoplasms are rarely encountered on EUS-FNA. The differential diagnosis encompasses a wide variety of benign and neoplastic entities. Correlation of cytomorphology and ancillary studies yields a high diagnostic accuracy of spindle cell and mesenchymal lesions on EUS-FNA.

Liu M, Qin W, Yin Z
An unusual case of primary mesenchymal chondrosarcoma in orbit with intracranial extension.
Clin Imaging. 2010 Sep-Oct; 34(5):379-81 [PubMed]

An unusual case of primary orbital mesenchymal chondrosarcoma with intracranial extension is reported, with special emphasis on the radiological findings.

Jaetli V, Gupta S
Mesenchymal chondrosarcoma of maxilla: a rare case report.
Med Oral Patol Oral Cir Bucal. 2011; 16(4):e493-6 [PubMed]

Mesenchymal chondrosarcoma (MC) is a rare variant of chondrosarcoma (CS) that accounts for upto 3-9% of all CS and has high predilection for the head and neck region. It is usually seen in younger age group compared to conventional CS and maxillary anterior alveolus is the most common site. The tumor is most unusual as it has been described as a particularly aggressive neoplasm with a high tendency for late recurrence and delayed metastasis. It is a biphasic tumor with areas comprising of spindle cell mesenchyme interspread with areas of chondroid differentiation. A 75 year old male presented to us as a painless mass in maxilla. Contrast enhanced computed tomography (CECT) revealed a lytic expansile lesion in the left maxillary bone with foci of calcification within soft tissue lesion. Fine needle aspiration cytology (FNAC) and incisional biopsy was performed which confirmed the diagnosis of maxillary MC. The patient underwent right and left subtotal maxillectomy with 2 cm margins. The review of literature shows that very few cases of maxillary MC have been reported so far. Thus an attempt is made to add this rare case of MC of maxillary alveolus in the English literature.

Küpeli S, Varan A, Gedikoğlu G, Büyükpamukçu M
Sacral mesenchymal chondrosarcoma in childhood: a case report and review of the literature.
Pediatr Hematol Oncol. 2010; 27(7):564-73 [PubMed]

Mesenchymal chondrosarcomas are rare malignant tumors in pediatric age group. The authors present a case of mesenchymal chondrosarcoma located in the sacrum in a 10-year-old-girl that was successfully treated with chemotherapy and radiotherapy after surgical excision. According to the authors' literature search, the patient is the first reported case of pediatric sacral primary mesenchymal chondrosarcoma. Mesenchymal chondrosarcoma cases in pediatric age group published in English literature was reviewed.

Bonavolonta P, Strianese D, Maria Luisa Vecchione MM, Staibano S
A challenging case of primary orbital mesenchymal chondrosarcoma.
Orbit. 2010; 29(5):281-3 [PubMed]

Mesenchymal chondrosarcoma is an uncommon lesion of the bone and extraskeletal tissue involving very rarely the orbit. Histopathological features of this lesion include: undifferentiated mesenchymal cells with islands of mature hyaline cartilage. We present a case of a 23-year-old man with primary orbital mesenchymal chondrosarcoma (OMC) with an uncommon management. This anecdotic report could be a contribution to the understanding of this unusual tumor.

Bu X, Dai X
Primary mesenchymal chondrosarcoma of the pancreas.
Ann R Coll Surg Engl. 2010; 92(3):W10-2 [PubMed]

Extraskeletal chondrosarcomas are rare and there is only one reported case of primary pancreatic chondrosarcoma. We report the case of a 34-year-old woman with a 6-month history of abdominal pain and distention. Radiological studies indicated a mass in the pancreas, and exploratory laparotomy revealed a tumour of the pancreas extending to the hepatic vessels and hepatoduodenal ligament. The mass was completely excised, and the histopathological diagnosis was primary mesenchymal pancreatic chondrosarcoma. Tumour recurred at follow-up 52 months postoperatively.

Zibis AH, Wade Shrader M, Segal LS
Case report: Mesenchymal chondrosarcoma of the lumbar spine in a child.
Clin Orthop Relat Res. 2010; 468(8):2288-94 [PubMed] Free Access to Full Article

BACKGROUND: Chondrosarcomas of the spine constitute 4% to 10% of all primary spinal bone tumors and approximately 70% of the cases occur during the second or third decade of life. Mesenchymal chondrosarcoma is a rare aggressive variant of chondrosarcoma. The prognosis of mesenchymal chondrosarcoma is usually poor with a tendency for late local recurrence and metastasis.
CASE DESCRIPTION: We describe a case of primary mesenchymal chondrosarcoma affecting the L5 vertebra of a 9-year-old girl. The patient underwent a staged circumferential resection of the tumor after three rounds of neoadjuvant chemotherapy. The patient had additional chemotherapy and radiation therapy as an intralesional margin was achieved during the procedure. At 9 years followup, the patient was asymptomatic, neurologically intact, and remained in remission.
LITERATURE REVIEW: We identified only four previously published cases of spinal mesenchymal chondrosarcoma in childhood, two of which had relatively early recurrence and poor survival, and two survived but with only short followup.
PURPOSES AND CLINICAL RELEVANCE: As the clinical and radiographic findings of mesenchymal chondrosarcoma are nonspecific, the diagnosis of this rare tumor requires careful histopathologic review of the specimens. We suggest the differential diagnosis of every primary intraspinal tumor include tumors of mesenchymal origin. The prognosis is apparently not uniformly poor.

Fanburg-Smith JC, Auerbach A, Marwaha JS, et al.
Reappraisal of mesenchymal chondrosarcoma: novel morphologic observations of the hyaline cartilage and endochondral ossification and beta-catenin, Sox9, and osteocalcin immunostaining of 22 cases.
Hum Pathol. 2010; 41(5):653-62 [PubMed]

Mesenchymal chondrosarcoma, a rare malignant round cell and hyaline cartilage tumor, is most commonly intraosseous but can occur in extraskeletal sites. We intensively observed the morphology and applied Sox9 (master regulator of chondrogenesis), beta-catenin (involved in bone formation, thought to inhibit chondrogenesis in a Sox9-dependent manner), and osteocalcin (a marker for osteoblastic phenotype) to 22 central nervous system and musculoskeletal mesenchymal chondrosarcoma. Cases of mesenchymal chondrosarcoma were retrieved and reviewed from our files. Immunohistochemistry and follow-up were obtained on mesenchymal chondrosarcoma and tumor controls. Twenty-two mesenchymal chondrosarcomas included 5 central nervous system (all female; mean age, 30.2; mean size, 7.8 cm; in frontal lobe [n = 4] and spinal cord [n = 1]) and 17 musculoskeletal (female-male ratio, 11:6; mean age, 31.1; mean size, 6.2 cm; 3 each of humerus and vertebrae; 2 each of pelvis, rib, tibia, neck soft tissue; one each of femur, unspecified bone, and elbow soft tissue). The hyaline cartilage in most tumors revealed a consistent linear progression of chondrocyte morphology, from resting to proliferating to hypertrophic chondrocytes. Sixty-seven percent of cases demonstrated cell death and acquired osteoblastic phenotype, cells positive for osteocalcin at the site of endochondral ossification. Small round cells of mesenchymal chondrosarcoma were negative for osteocalcin. SOX9 was positive in both components of 21 of 22 cases of mesenchymal chondrosarcoma. beta-Catenin highlighted rare nuclei at the interface between round cells and hyaline cartilage in 35% cases. Control skull and central nervous system cases were compared, including chondrosarcomas and small cell osteosarcoma, the latter positive for osteocalcin in small cells. Mesenchymal chondrosarcoma demonstrates centrally located hyaline cartilage with a linear progression of chondrocytes from resting to proliferative to hypertrophic, which undergoes endochondral ossification, recapitulating growth plate cartilage and suggesting that this component of mesenchymal chondrosarcoma may be a differentiated (benign or metaplastic) component of a malignant metastasizing tumor. This hyaline cartilage component is morphologically different from cartilage of control chondrosarcoma. Mesenchymal chondrosarcoma can be separated from small cell osteosarcoma, using Sox 9 for cartilage and osteocalcin for osteoblastic phenotype. Rare nuclear beta-catenin expression at the interface between hyaline cartilage and small round cells potentially implicates the APC/Wnt pathway during endochondral ossification in morphologically benign hyaline cartilage component of mesenchymal chondrosarcoma.

Fanburg-Smith JC, Auerbach A, Marwaha JS, et al.
Immunoprofile of mesenchymal chondrosarcoma: aberrant desmin and EMA expression, retention of INI1, and negative estrogen receptor in 22 female-predominant central nervous system and musculoskeletal cases.
Ann Diagn Pathol. 2010; 14(1):8-14 [PubMed]

Mesenchymal chondrosarcoma is a rare malignant tumor in the differential diagnosis of other small, round blue cell tumors, including atypical teratoid tumor in the central nervous system (CNS) and rhabdomyosarcoma in the musculoskeletal (MSK) locations. We reviewed the morphology of CNS and MSK cases and applied a panel of immunostains. Archival cases were pulled from our files. Immunohistochemistry and follow-up were obtained. Twenty-two cases included 5 CNS (all female; mean age, 30.2) and 17 MSK (11 female and 6 male; mean age, 31.1). Both CNS and MSK examples had similar round cells, staghorn vascular pattern, increased mitotic activity, and centrally located hyaline cartilage islands. The CNS examples demonstrated more spindling and the MSK cases more necrosis. INI1 was retained in all tumors studied. Epithelial membrane antigen (EMA) and desmin were expressed focally in 35% and 50% of cases, respectively. The round cells of all cases were negative for MyoD1, myogenin, smooth muscle actin (SMA), glial fibrillary acid protein (GFAP), keratins, and estrogen receptor, as well as a panel of other antiobodies. Eighty percent of patients with follow-up had pulmonary metastases and/or died within a mean of 5 years. The CNS and MSK mesenchymal chondrosarcoma predominantly affects adult females with poor prognosis. There are only subtle morphologic differences between the CNS and MSK groups. By immunohistochemistry, mesenchymal chondrosarcoma occasionally expresses aberrant desmin and EMA but is negative for SMA, myogenin MyoD1, GFAP, and keratins, refuting true smooth or skeletal muscle, epithelial, or meningothelial phenotype. Retained INI1 separates these tumors from atypical teratoid tumor. Despite marked female predominance in our series, estrogen receptor is negative in mesenchymal chondrosarcoma.

Handa U, Singhal N, Punia RS, et al.
Cytologic features and differential diagnosis in a case of extraskeletal mesenchymal chondrosarcoma: a case report.
Acta Cytol. 2009 Nov-Dec; 53(6):704-6 [PubMed]

BACKGROUND: Extraskeletal myxoid chondrosarcoma (EMC) is an uncommon tumor. On fine needle aspiration (FNA) it has to be distinguished from other benign and malignant soft tissue lesions.
CASE: FNA was done on an 85-year-old man with painful swelling of the forearm. Smears showed fragments comprised of polygonal cells with eccentric nuclei and peripheral fine cytoplasmic vacuoles embedded in a dense, metachromatic matrix. Cell block showed similar cells in a chondromyxoid stroma. The cells were positive for S100 and negative for cytokeratin.
CONCLUSION: FNA is a useful tool in the diagnosis of EMC in conjunction with radiology. A preoperative diagnosis can be made due to its distinct cytologic and immunohistochemical features, obviating the need for a biopsy.

Razak AR, Gurney L, Kirkham N, et al.
Mesenchymal chondrosarcoma of the orbit: an unusual site for a rare tumour.
Eur J Cancer Care (Engl). 2010; 19(4):551-3 [PubMed]

Mesenchymal chondrosarcoma is a rare tumour with orbital involvement being an exceptional occurrence. We present a case of a 22-year old man with such disease, together with details of his management. A brief literature review of this uncommon tumour was also enclosed.

Font RL, Ray R, Mazow ML, Del Valle M
Mesenchymal chondrosarcoma of the orbit: a unique radiologic-pathologic correlation.
Ophthal Plast Reconstr Surg. 2009 May-Jun; 25(3):219-22 [PubMed]

PURPOSE: To report a unique radiologic-histopathologic correlation of mesenchymal chondrosarcoma of the orbit in a 24-year-old Asian woman.
METHODS: Clinicopathologic case review.
RESULTS: The patient was examined for left-sided proptosis of several months' duration. CT showed a left orbital mass depicting a central radiolucent, nonenhancing component, and a denser peripheral enhancing portion. Histopathologic examination of the orbital mass showed a biphasic pattern of a mesenchymal chondrosarcoma exhibiting features of a high-grade sarcoma with hemangiopericytoma pattern that corresponds to the radiopaque portion of the mass and areas of chondrosarcoma that correlated with the radiolucent component of the tumor. The patient underwent exenteration of the left orbit followed by radiotherapy and chemotherapy. The last follow-up (8 years, 1 month) disclosed no evidence of recurrence or metastatic disease.
CONCLUSIONS: In this case, a unique CT-histopathologic correlation of the mass was established. The authors believe that recognizing the different radiologic features of the orbital tumor can help clinicians in establishing the correct preoperative diagnosis of this potentially lethal neoplasm. To the best of the authors' knowledge, this diagnostic correlation has not been previously reported.