Introduction Malignant chondrogenic lesions can occur in two forms primary chondrosarcoma which includes low-grade, high-grade, de-differenitated chondrosarcoma clear cell chondrosarcoma (see below) mesenchymal chondrosarcoma (see below) secondary chondrosarcoma arises from benign cartilage lesions including osteochondroma (<1% risk of malignant transfomation) multiple hereditary exostosis (1-10% risk of malignant transfomation) enchondromas (1% risk of malignant transfomation) Ollier's disease (25-40% risk of malignant transfomation) Maffucci's (100% risk of malignant transfomation) Age & location typically, chondrosarcomas are found in older patients (40-75 yrs) there is a slight male predominance most common locations include the pelvis, proximal femur, scapula tumor location is important for diagnosis as the same histology may be diagnosed as benign in the hand but malignant if located in the long bones Grade 85% of chondrosarcomas are grade 1 or 2 15% of chondrosarcomas are grade 3 or dedifferentiated chondrosarcoma de-differentiated chondrosarcomas are high grade lesions which develop from low grade chondroid lesions Prognosis axial and proximal extemity lesions have a more aggressive course histologic grade correlates with survival Grade I: 90% survival Grade II: 60-70% survival Grade III: 30-50% survival De-differentiated chondrosarcoma: 10% survival increased telomerase activity in chondrosarcoma, as determined by reverse transcriptase-polymerase chain reaction (RT-PCR), has been shown to directly correlate with the rate of recurrence Chondrosarcoma sub-types clear cell chondrosarcoma malignant immature cartilaginous tumor accounting for <2% of all chondrosarcomas most common in 3rd and 4th decades of life commonly presents with insidious onset of pain presents as an epiphyseal lesion and can be mistaken for low-grade chondroblastoma locally destructive with potential to metastasize mesenchymal chondrosarcoma chondrosarcoma variant which presents with a biphasic pattern of neoplastic cartilage with associated neoplastic small round blue cell component occurs in younger patients than typical chondrosarcomas may occur at several discontinuous sites at presentation and can occur in the soft tissues treatment includes neo-adjuvant chemotherapy followed by wide surgical resection Presentation Symptoms pain is the most common symptom may present with slowly growing mass or symptoms of bowel/bladder obstruction due to mass effect in the pelvis 50% of de-differentiated chondrosarcomas present with a pathologic fracture Imaging Radiographs lytic or blastic lesion with reactive thickening of the cortex low-grade chondrosarcomas show similiar appearance to enchondromas with additional cortical thickening/expansion and endosteal erosion high-grade chondrosarcomas show cortical destruction and a soft tissue mass intra-lesional "popcorn" mineralization may be seen described as rings, arcs, and stipples of mineralization de-differentiated chondrosarcomas radiographically show a lower grade chondroid lesion with superimposed highly destructive area consistent with the high grade transformed dedifferentiated chondrosarcoma MRI or CT helpful to determine cortical destruction, marrow involvement, and the soft tissue involvement Bone scan is usually very hot in all grades of chondrosarcoma Histology Chondrosarcoma needle biopsy is not indicated for cartilage tumors due to difficulties with diagnosis it is often difficult to determine malignancy based on histology alone chararcteristic histology low-grade chondrosarcomas show few mitotic figures with a bland histologic appearance enlarged chondrocytes with plump multinucleated lacunae high-grade chondrosarcomas show hypercellular stroma consisting of characteristic "blue-balls" of a cartilage lesion which permeate the bone trabeculae enchondromas of hand, Ollier's disease, Maffucci's disease, periosteal chondromas, and chondrosarcoma may all have similar histology De-differentiated chondrosarcomas characterized by a bimorphic histology low grade chondroid component high grade spindle cell component (similiar histology to osteosarcoma, fibrosarcoma, MFH) Treatment Operative intra-lesional curettage indications Grade 1 lesions treatment of grade 1 lesions located in the pelvis or axial skeleton is controversial many authors recommend wide excision of all chondrosarcomas (even grade 1) if located in the pelvis wide surgical excision indications grade 2 or 3 lesions some say grade 1 lesions in pelvis historically, there is no significant role for radiation or chemotherapy in typical intramedullary chondrosarcoma wide surgical excision combined with multi-agent chemotherapy indications mesencymal chondrosarcoma the role of chemotherapy in de-differentiated chondrosarcoma is very controversial Differentials & Groups Malignant lesion in older patient(1) May have similar chondrogenic histology Sacral lesions in older patients Treated with wide resection alone (2) Chondrosarcoma • • • • Metastic disease • • Lymphoma • • Myeloma • • MFH • • Secondary sarcoma • Enchondroma / Olliers / Marfuccis • Periosteal chondroma • Osteochondroma (MHE) • Parosteal osteosarcoma • Adamantinoma • Chordoma • • Squamous cell(3) • • ASSUMPTIONS: (1) Older patient is > 40 yrs; (2) assuming no impending fracture (3) assuming no squamous cell metastatic disease IBank Location Xray Xray CT B. Scan MRI MRI Histo(1) Case A scapula Case B femur Case C pelvis Case D tibia Case E prox femur Case F prox. humerus Case H pelvis (dedifferentiated) Case I femur (dedifferentiated) (1) - histology does not always correspond to case