Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fibrous orbital tumors present clinically and radiographically in a broad spectrum ranging from a benign mass, to locally aggressive tumor, to invasive malignancy. Pathologic analysis and diagnosis are often challenging, usually based on a combination of light microscopy, immunohistochemistry, and electron microscopic findings. Some light microscopic and immunohistochemical findings, however, are relatively characteristic. A storiform or cartwheel pattern and vimentin staining are characteristic of fibrous histiocytoma. A herringbone pattern is usually found in fibrosarcoma. A "patternless pattern" and CD34 staining is found most commonly in solitary fibrous tumor. CT and MR imaging findings, as well as clinical presentation, in fibrous orbital lesions are often difficult to distinguish from those of other orbital masses, although there may be useful clues. Benign fibrous lesions are usually well-circumscribed and may chronically remodel bone, whereas more aggressive malignant fibrous tumors tend to have infiltrating margins and may destroy bone on CT or MR imaging. With malignant fibrous masses, enhancement patterns on CT or MR imaging may be more inhomogeneous, with avascular or necrotic nonenhancing regions. At MR imaging, benign lesions tend to be homogeneous on T1, T2, and postgadolinium T1-weighted images, whereas malignant soft tissue lesions may change their pattern from homogeneous on T1-weighted images to heterogeneous with low signal septations on T2-weighted images. Low T2 signal comprising part or all of a fibrous lesion correlates with dense collagen fibers, with a less cellular matrix. Areas of hyperintensity on T2-weighted images correspond with a more cellular matrix of fibroblasts and other cells. Calcification within a tumor, however, may give a similar appearance. Thus, if a lesion has predominantly low signal on T2-weighted images, or less specifically has low signal septations, then a fibrous orbital lesion with high collagen content may be ranked higher in the differential diagnosis (see Figs. 2E and 3B). When T2 signal is intermediate-to-high, then one has a difficult time narrowing the differential diagnosis. Radiographically, distinguishing these lesions from other fibrous orbital lesions, as well as from other varieties of orbital masses, is difficult. Differential diagnosis of fibrous orbital masses includes all the fibrous lesions described in this article, in addition to schwannoma (Fig. 7), neurofibroma (Figs. 4 and 8), hemangiopericytoma (Figs. 9 and 10), rhabdomyosarcoma, meningioma, lymphoma, and metastasis (Figs. 11 and 12). A history of prior orbital irradiation for retinoblastoma or other tumors may raise the possibility of radiation-induced secondary tumors, such as MFH, fibrosarcoma, and osteosarcoma. Determining the extent of orbital involvement remains the primary goal of the radiologist. The final diagnosis still rests with the pathologist.
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PMID:Fibrous histiocytoma and fibrous tissue tumors of the orbit. 1002 37

The clavicle is frequently incorporated into the radiation field in the treatment of malignant tumors located in the head and neck. From 1954 to 1995, 499 pediatric patients were treated with moderate to high-dose radiation therapy to the head and neck at the University of Texas M.D. Anderson Cancer Center. The medical records of 312 of these patients were available and were reviewed. The period of observation ranged from 5 to 30 years. Five late radiation-induced abnormalities of the clavicle were encountered: osteosarcoma; osteochondroma; malignant fibrous histiocytoma; radionecrosis and impaired healing following trauma and radionecrosis and lysis. The doses of radiation therapy which induced the abnormalities varied from 35 to 60.5 Gy (median 34.75 Gy). The interval from radiation therapy to discovery of the complications varied from 6 to 11 years. Two patients died: one from malignant fibrous histiocytoma and another from a radiation-induced meningioma of the brain (which accompanied radionecrosis of the clavicle). We conclude that the incidence of radiation-induced abnormalities of the clavicle in pediatric long-term survivors is low (1.5%). However, some of the late sequela are potentially fatal. The clavicle should be considered a vulnerable bone to radiation therapy and should be monitored in long-term survivors of childhood cancer. The experience is compared to radiation-induced abnormalities recorded in the literature.
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PMID:The clavicle: a vulnerable bone in pediatric oncology. 1125 Nov 62

Low-affinity nerve growth factor receptor (p75) is a member of the tumor necrosis factor receptor family. It may modulate the binding of nerve growth factor (NGF) to the functional high-affinity receptor tyrosine kinase (trk) A. NGF is thought to be responsible for growth, apoptosis, and function of the nervous system. The presence of this receptor (p75) was determined in a large group of neural and nonneural tumors and fetal and adult tissues. One thousand one hundred fifty tumors were analyzed with monoclonal antibody for p75, along with selected normal fetal and adult tissues. Immunoreactivity for p75 was present in adult pericytes, perivascular fibroblasts, basal cells of several types of epithelia, perineurial cells, and dendritic reticulum cells. Additionally, a wide zone of subepithelial mesenchyme and skeletal muscle were positive in the first-trimester fetus, but were diminished or negative in the adult. Consistently positive nonneural mesenchymal tumors included dermatofibrosarcoma protuberans (DFSP), embryonal and alveolar rhabdomyosarcoma, synovial sarcoma, and spindle cell hemangio(endotheli)oma. Schwann cell tumors, ganglioneuroma, granular cell tumor, and malignant peripheral nerve sheath tumor (MPNST) were also p75 positive. Mesenchymal nonneural tumors that were variably positive (32% to 69%) for p75 included fibrosarcoma variants, solitary fibrous tumor, hemangiopericytoma, spindle cell lipoma, Ewing's sarcoma, mesenchymal chondrosarcoma, and malignant melanoma. Nervous system tumors such as paragangliomas, neuroblastoma, meningioma, and perineurioma and nonneural mesenchymal tumors, including extraskeletal osteosarcoma, benign fibrous histiocytomas, fibromas, alveolar soft part sarcoma, epithelioid sarcoma, smooth muscle and gastrointestinal stromal tumors, and angiosarcomas, were almost always negative for p75. Epithelial tumors that were consistently positive included mixed tumor and adenoid cystic carcinoma, whereas mesothelioma, adenocarcinomas, and most squamous cell carcinomas were negative. p75 is not a specific marker for nerve sheath tumors. It is present in a variety of other mesenchymal tumors including synovial sarcoma and in CD34-positive tumors such as DFSP, spindle cell lipoma, and hemangiopericytoma. The presence of p75 in nonneural tumors such as DFSP and rhabdomyosarcoma mimic its presence in early fetal mesenchyme and skeletal muscle, suggesting oncofetal expression in these tumors. p75 may be useful to distinguish DFSP from benign fibrous histiocytoma.
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PMID:Low-affinity nerve growth factor receptor (p75) in dermatofibrosarcoma protuberans and other nonneural tumors: a study of 1,150 tumors and fetal and adult normal tissues. 1156 28

A 20-year-old male presented with an osteosarcoma in the right parieto-occipital bone occurring as a painless occipital lump which had rapidly enlarged in the 6 months prior to admission. The neuroimaging appearance resembled intraosseous meningioma. Gross total resection of the tumor was achieved. The final histological diagnosis was osteosarcoma. Osteosarcomas of craniofacial region have a better prognosis than those of the skeletal bones, and distant metastasis is rare. Local recurrence is the most significant factor contributing to poor outcome. Complete excision with negative margins is the key to a better outcome. Adjuvant therapy may be an option in cases of incomplete excision. Advances in target chemotherapy may diminish the significant morbidity associated with these lesions.
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PMID:Osteosarcoma arising from the skull--case report. 1262 87

A case is reported in which the amputation of a leg for a sclerosing type of osteogenic sarcoma was followed five years later by a metastasis of similar appearance in the skull. This was excised but subsequent necropsy revealed multiple bony tumours in the lungs. The rarity of multiple osteogenic sarcoma is recalled as shown by a review of the literature. Although some are thought to be of multicentric origin owing to the short history, an early haematogenous spread cannot be excluded and this latter process had certainly occurred in the present case. The characteristic radiological appearances in the skull are stressed as being diagnostic. The differential points in the histological diagnosis of the condition, especially in the invaded part of the calvarium, are described and should help to exclude a meningioma or other bone tumours.
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PMID:Sclerosing osteogenic sarcomatosis. 1378 31

A 56-year-old woman presented with an intracranial osteosarcoma at the site of previous radiosurgery, manifesting as sudden onset of headache and left hemiparesis with aphasia. She had a previous history of stereotactic radiosurgery for an intracranial tumor under a diagnosis of falx meningioma. Computed tomography showed intratumoral and peritumoral hemorrhage at the right parietofrontal region. Gross total resection of the tumor with hematoma was performed. The histological diagnosis was osteosarcoma. Sarcomatous change is a rare complication of radiotherapy. This case illustrates that osteosarcoma may develop years after radiosurgery for benign brain neoplasm.
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PMID:Intracranial osteosarcoma after radiosurgery--case report. 1495 34

Periosteal osteoblastoma is an extremely rare bone-forming neoplasm located on the surface of cortical bone. Of the fewer than 30 cases of periosteal osteoblastomas found in the literature, 2 have been reported to be located in cranial bone, and these have not been documented in detail with clinical history, radiographic findings, macroscopic features, and microscopic findings. Although the differential diagnoses of periosteal lesions include parosteal and periosteal osteosarcoma, periosteal chondroma and chondrosarcoma, osteochondroma, osteoid osteoma, periostitis ossificans, and myositis ossificans, an important differential diagnosis both radiologically and pathologically of such a lesion in the cranium is meningioma. We report an unusual case of periosteal osteoblastoma located in the frontal cranial bone that was radiologically consistent with a meningioma. The differential diagnosis of metaplastic meningioma with differentiation toward bone is discussed.
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PMID:A rare case of periosteal osteoblastoma located in the frontal cranial bone. 1591 30

Primary meningeal osteosarcomas are rare tumors, with only 19 reported cases in the literature; only 4 of these, including the present case, are in pediatric patients. In this report, the authors present the case of an 8-year-old boy with a history of generalized tonic-clonic seizures who was found to harbor a meningeal osteosarcoma within the sylvian fissure. Initial working diagnoses included meningioma and glioma. After tumor enlargement and progressive symptoms, the patient underwent a large frontotemporal craniotomy and complete resection of the lesion, which recurred 6 and 12 months after the initial surgery and was surgically treated after each recurrence. The rarity of primary meningeal osteosarcomas can make their diagnosis difficult, and histopathological evaluation is mandatory for diagnosis. Because of their fast progression, they must be treated aggressively by means of surgery, chemotherapy, and radiotherapy.
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PMID:Primary meningeal osteosarcoma of the brain during childhood. Case report. 1837 10

A 53-year-old man presented with a rare meningioma associated with Werner syndrome. Screening brain magnetic resonance (MR) imaging with gadolinium had detected multiple homogeneously enhanced tumors in the right convexity and in the anterior and posterior thirds of the falx cerebri after surgery for osteosarcoma in his right leg at age 52 years. Ten months later, the right convexity tumor was removed because follow-up MR imaging detected tumor growth. The histological diagnosis was transitional meningioma. The postoperative clinical course was good and the patient remains healthy. Review of the literature found meningiomas associated with Werner syndrome occur about two times more frequently in men than in women, and typically in the fourth decade. Most meningiomas associated with Werner syndrome are benign, but are sometimes complicated with extracranial tumors such as sarcoma, thyroid carcinoma, and others. Patients with meningioma associated with Werner syndrome should be carefully followed up to detect the occurrence of other extracranial tumors such as sarcoma by brain MR imaging, echography, or body computed tomography.
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PMID:Meningioma associated with Werner syndrome--case report--. 1894 83

We report a case of post-radiation dedifferentiation of meningothelial meningioma into chondroblastic osteosarcoma. The tumor developed in a 61-year-old man, seven years after adjuvant stereotactical radiotherapy of recurring meningioma. Histologically, there was a continuous transition from atypical meningioma into chondroblastic osteosarcoma. The patient died three weeks after the surgery, without additional oncological treatment. To our knowledge, this case represents only the second reported case of post-radiation dedifferentiation of meningioma into osteosarcoma.
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PMID:[Post-radiation dedifferentiation of meningioma into chondroblastic osteosarcoma]. 1940 18


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