<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A malignant neoplasm usually arising from bone.</n0:def-definition><n0:def-source>CDISC</n0:def-source></n0:ComplexDefinition><n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A malignant bone-forming tumor of osteocytes. Osteoid may be present only focally. This term may be used for small biopsy specimens for which adequate tissue is not present for definitive classification.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>
<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A usually aggressive malignant bone-forming mesenchymal tumor, predominantly affecting adolescents and young adults. It usually involves bones and less frequently extraosseous sites. It often involves the long bones (particularly distal femur, proximal tibia, and proximal humerus). Pain with or without a palpable mass is the most frequent clinical symptom. It may spread to other anatomic sites, particularly the lungs.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>