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)

Fifty-seven patients undergoing chemotherapy for osteosarcoma underwent evaluation with magnetic resonance (MR) imaging to identify changes related to a good or poor response. Spin-echo MR images obtained after preoperative chemotherapy were compared with images obtained before treatment. Histopathologic examination of each resected specimen was used to quantify the response. An increase in tumor volume and increased or unchanged edema were predictive of a poor histopathologic response (predictive values, 85%-92%). Decreased or unchanged tumor volume and a decrease in edema were poor predictors of a good response (predictive values, 56%-62%). Improved tumor demarcation, an increase in the size of areas of low signal intensity, and a decrease in joint effusion occurred independently of histopathologic response in almost half of the patients. With a subjective interpretation of MR images, poor respondents can be identified if an increase in tumor volume or no decrease in the amount of edema is seen. Subjective criteria do not contribute to the identification of good respondents.
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PMID:Osteosarcoma: chemotherapy-induced changes at MR imaging. 153 5

The computed tomographic (CT) scans and medical records of 35 patients with proven benign soft-tissue masses of the extremities were reviewed to assess the contribution of CT in the evaluation of such masses. CT demonstrated the mass in all 35 cases and was able to provide a specific diagnosis in 28 (80%); 25 prospectively, three retrospectively. Correct diagnoses made using CT included hematomas (five), synovial cysts (seven), myositis ossificans (six), fatty tumors (four), aneurysms (three), pseudoaneurysms (two), schwannoma (one), and abscess (one). The CT appearance of a hematoma depends on its age. Synovial cysts are near-water-density masses, often associated with a small joint effusion. Myositis ossificans can be differentiated from parosteal osteosarcoma by virtue of its characteristic zonal ossification. Lipomas are recognized on noncontrast scans by the characteristic low attenuation of fat, while aneurysms and pseudoaneurysms are best diagnosed on postcontrast scans. In seven cases (20%) a specific diagnosis could not be made on the basis of the CT scan. However, in these cases CT delineated the extent of the mass and demonstrated its relation to surrounding structures; this anatomic information was helpful in planning surgical excision or percutaneous biopsy. The authors conclude that CT is a valuable noninvasive imaging method for the evaluation of soft-tissue masses of the extremities.
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PMID:CT of benign soft-tissue masses of the extremities. 660 49

The effects of preoperative chemotherapy for osteosarcoma of the extremities were investigated with MR imaging. Forty-six patients affected with high-grade osteosarcomas of the extremities underwent MRI before and after two cycles of preoperative chemotherapy. At the end of treatment all tumors were resected and the rate of tumor necrosis was assessed on histologic sections. The MR images obtained before and after treatment were compared. Decreased tumor size, perilesional intramedullary edema and more marked lesion outline correlated well with positive histologic response to preoperative chemotherapy. Soft tissue edema and joint effusion did not change significantly and no clear correlation with histologic response was observed. Decreased signal intensity on T2-weighted images is likely to indicate response to chemotherapy. Likewise, poor response correlated with unchanged/increased signal intensity. Therefore, MRI appears a useful means to evaluate chemotherapy-induced changes in osteosarcomas of the extremities.
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PMID:[Osteosarcoma: magnetic resonance imaging of the effects of preoperative chemotherapy]. 833 28