Mesenchymal chondrosarcoma - A rare cause of pleural effusion

Mesenchymal chondrosarcoma is a malignant neoplasm arising from cartilaginous bone or soft tissue. It is uncommon yet devastating. Our patient was a 21-year-old man who presented with pleuritic chest pain and weight loss. His chest radiograph showed left pleural effusion. His pleural effusion analysis was consistent with exudative pleural effusion. Tuberculosis workup was negative. Pleural fluid cytology did not yield malignant cells. Subsequently, his computed tomography of thorax showed left rib sclerotic lesion with soft tissue component. Biopsy of the soft tissue eventually confirmed the diagnosis of mesenchymal chondrosarcoma. He succumbed to his illness before the diagnosis was confirmed. We hope that through this case report, we are able to provide some insight into this rare condition.

Tumor-induced hypophosphatemic rickets in an adolescent boy--clinical presentation, diagnosis, and histological findings in growth plate and muscle tissue

CONTEXT

The mechanism behind disabling muscle weakness in tumor-induced hypophosphatemic rickets is obscure. Histological investigation of growth plate tissue of patients with tumor-induced osteomalacia has so far not been reported.

PATIENT

A mesenchymal tumor was detected in the left distal fibula by (68)Ga-DOTATOC in a 17-yr-old boy with adolescent onset of severe hypophosphatemic rickets. Disabling muscle weakness improved within days after surgery, and normal mobility was restored within months.

METHODS AND RESULTS

The resected tissue included part of the growth plate allowing immunohistochemical investigation. Positive staining of FGF23 was found in the tumor cells and in hypertrophic chondrocytes, osteoblasts, and osteoclasts of the adjacent growth plate. This distribution matched that found in growth plate tissue of a healthy control. We found positive staining for the somatostatin receptor not only in the tumor but also within the growth plate and adjacent bony tissue in the patient and the healthy control. Muscle tissue provided evidence for a partial defect in respiratory chain complexes I-IV. Biochemical markers were nearly or completely restored to normal 12 months after surgery.

CONCLUSIONS

Hypertrophic growth plate chondrocytes are a target or source of FGF23 in tumor-induced osteomalacia. Low serum phosphate, FGF23, or other factors produced by the tumor may interfere with mitochondrial function.

Oncogenic osteomalacia in a case with a maxillary sinus mesenchymal tumor

We herein describe the rare case of a 41-year-old woman with oncogenic osteomalacia due to a tumor in the maxillary sinus who presented with chronic general pain that had been gradually deteriorating. The patient's laboratory findings revealed hypophosphatemia due to renal phosphate wasting, an inappropriately low serum 1 alpha,25-dihydroxyvitamin D3 level for hypophosphatemia and an unusually high serum level of fibroblast growth factor 23 (FGF23). The causative tumor was surgically removed, resulting in a rapid resolution of the patient's biochemical abnormalities. An improvement of the abnormal multiple deposits on (99)Technetium-methylene diphosphonate bone scintigraphy and an increase in the bone metabolism markers suggested the development of bone remodeling within 49 days after the operation. The pathologic diagnosis of the tumor was a "phosphaturic mesenchymal tumor, mixed with a connective tissue variant." The expression of FGF23 was demonstrated in the tumor by the immunohistochemical techniques and a Western analysis.

Femoral mesenchymal chondrosarcoma with secondary aneurysmal bone cysts mimicking a small-cell osteosarcoma

Mesenchymal chondrosarcoma is a rare but aggressive, high-grade malignancy of primitive cartilage-forming mesenchyme that arises most commonly from skeletal sites. Although there are radiological findings suggestive of the diagnosis, imaging features often overlap with those of other skeletal sarcomas. The definitive diagnosis relies on the histological finding of a typical bimorphic appearance, consisting of nests of small, round, poorly differentiated cells and more mature cartilaginous tissue. To highlight this, we present the case of a 21-year-old man who was referred to our institution with a history of right knee pain. Initial imaging and histological evaluation of a core biopsy of the lesion suggested osteosarcoma of the distal right femur; after review, however, the correct diagnosis of mesenchymal chondrosarcoma was made. Adequate tissue sampling and thorough histological evaluation of biopsy specimens is vital for the accurate diagnosis of primary bone malignancies, especially those of chondroid origin.

Intracranial mesenchymal chondrosarcoma with osteoid formation: report of a pediatric case

CASE REPORT

We present a case of a 14-year-old girl with a 3-week history of severe progressive headache and intermittent vomiting. Magnetic resonance imaging (MRI) revealed a large intensely enhancing mass, which seemed to arise from the right side of the cerebral fossa with implant base in the inferior face of the tentorium and significant mass effect on the nearby structures. A presumptive preoperative diagnosis of meningioma was made. Subtotal surgical resection was performed using the occipital approach. Histologically the neoplasms had the classic features of a mesenchymal chondrosarcoma associated with the focal presence of osteoid matrix.

DISCUSSION

Clinical features, therapeutic approaches and prognosis of this rare tumour are discussed with regard to the known 30 cases in the literature.

Mesenchymal chondrosarcoma of the vagus nerve

Mesenchymal chondrosarcoma is a rare, aggressive, malignant neoplasm, which arises from extraskeletal sites in 30-40 per cent of cases. It is extremely rare in children. We present a novel case of childhood mesenchymal chondsarcoma arising from the vagus nerve in the neck, resulting in paralysis of the right vocal fold. The clinicopathologic features and management of this case are described along with a brief discussion on the aetiology of vocal fold paralysis in this age group. Current literature on extraskeletal presentation of mesenchymal chondrosarcoma is reviewed.

Microvasculature and VEGF expression in cartilaginous tumors

We examined the microvasculature and VEGF expression in 26 cartilaginous lesions (CL) including 5 enchondromas, 9 grade 1 chondrosarcoma (CS), 6 grade 2 CS, 4 grade 3 CS, 1 mesenchymal, and 1 myxoid chondrosarcoma. The degree of neovascularization was measured by counting microvessels on H&E and factor VIII related antigen immunostained slides. Vessels were divided into pericartilage vessels (PCV) and intracartilage vessels (ICV). PVC comprised vessels around the lobules or invading the lobules but themselves surrounded by noncartilaginous stroma (ie, fibrous stroma); ICV consisted of those vessels present inside the tumoral nodules and in direct apposition with malignant cells or tumoral stroma. A direct correlation was seen between histological type and grade of CS and pericartilage vessels. In contrast, ICV were found only in higher-grade CS. No enchondromas and only 1 of 9 grade 1 CS had ICV. This patient had Ollier's disease. All but 2 of the grade 2 CS showed ICV (average, 20.5). The exceptions were predominantly grade 1 CS with focal grade 2 areas and extensive areas of necrosis. All but 1 grade 3 CS had ICV, the exception being a case of metastatic CS to the lung. Malignant chondrocytes of high-grade lesions stained strongly for vascular endothelial growth factor (VEGF), a potent angiogenic factor. The only high-grade tumors that did not express VEGF did not show ICV either. Enchondromas and grade 1 CS, most without ICV, did not express VEGE In summary, PCV are present in all categories of tumoral cartilage and the number increases with histological grade; ICV are found in high-grade lesions, and the exceptions show extensive necrosis; VEGF expression by malignant chondrocytes is seen in high-grade lesions almost exclusively, and among these in those lesions that showed intracartilage vessels. It is possible that PCV are involved in supporting tumor growth, whereas ICV might be involved in the acquisition of metastatic potential by cartilage tumors. VEGF expression is strongly associated with the presence of ICV.

Tumor-induced osteomalacia and symptomatic looser zones secondary to mesenchymal chondrosarcoma

Tumor-induced osteomalacia is a rare clinical entity that is associated with soft-tissue or skeletal tumors. We present a case report of a patient with a chest wall mesenchymal chondrosarcoma who presented with bone pain. The patient had skeletal changes in the femoral neck and fibula consistent with osteomalacia and laboratory values suggesting phosphate diabetes. The patient was treated with tumor resection and phosphate supplementation with reversal of the signs and symptoms of osteomalacia. Tumor-induced osteomalacia is vitamin-D-resistant and often reversed by complete removal of the tumor. Most commonly, the causative tumors are of vascular, mesenchymal, or fibrous origin. The osteomalacia is associated with bone pain, muscle weakness, and radiographic changes. Tumor-induced humoral factors have been implicated in causing the osteomalacia, but the definite etiology has yet to be determined. Current treatment includes complete tumor resection and electrolyte supplementation.