A chondrosarcoma is a malignant tumor derived from cartilaginous cells. They are the second most common malignant bone tumor and have varied behavior and features. Chondrosarcomas are classified according to location with central chondrosarcomas originating within the intramedullary canal and peripheral chondrosarcoma arising outside the intramedullary canal. Primary lesions arise without a pre-existing lesion and secondary chondrosarcomas come from a lesion such as an enchondroma or osteochondroma.
Expect the first symptom to be dull pain and possibly some local swelling. The patient typically has these symptoms for one to two years before going to a doctor. A chondrosarcoma also may manifest as a pathologic fracture.
Use radiographs to initially diagnose a chondrosarcoma. It also may be supplemented with a Computed Tomography (CT) scan which is helpful for detecting calcification and confirming cortical scalloping in the case of central chondrosarcomas.
Perform a Magnetic Resonance Imaging (MRI) to determine the extent of central chondrosarcomas although it is less sensitive than a CT scan in detecting calcification within a tumor. An MRI also is useful in examining the cartilage gap in an osteochondroma that may develop into a secondary chondrosarcoma.
Evaluate the images to determine the malignancy of the tumor. Existing benign bone tumors should be monitored carefully for progression into a sarcoma. The degree of cortical destruction and the presence of a soft tissue mass are indicators of malignancy. A previously existing enchondroma that now shows the destruction of a calcified matrix also indicates malignancy.
Confirm the diagnosis with a biopsy. The biopsy is usually performed as an open surgical procedure and the bone sample's histological characteristics are determined.