<unk>  is the second most common malignant primary tumor of bone. it is most frequently diagnosed in patients in their 4th and 5th decades of life.Men are slightly more affected with<unk>  than women. There is no racial predilection to<unk> . Jaffe and Lichtenstein first described<unk>  in 1948.<unk>  may be classified based on histological findings and location. The exact pathogenesis of<unk>  is not fully understood. Multiple genes have been implicated in pathogenesis of<unk> . Cytogenetic analysis of<unk> s revealed that structural abnormalities of chromosomes 1, 6, 9, 12 and 15 and numerical abnormalities of chromosomes 5, 7, 8 and 18 are most frequent associated. Anomalies associated with chromosome 9(9p12-22) are more commonly seen in central<unk> s. Germline mutations in the exostosin (EXT1 or EXT2) genes, TP53 or pRb pathway, isocitrate dehydrogenase-1 and isocitrate dehydrogenase 2 genes and gene encoding the receptor for parathyroid have been implicated. On gross pathology, greyish-white lobulated mass, necrosis, calcification, and mucoid degeneration are characteristic findings of<unk> . On microscopic histopathological analysis abnormal cartilage, increased cellularity, and nuclear atypia are characteristic findings of<unk> .<unk>  may be divided into three grades based on cancer cells morphology under microscope and growth rate of tumor. There are no established causes for<unk> . Common risk factors in the development of<unk>  are benign cartilage tumors such as enchondromas, osteochondromas, multiple exostoses, Ollier's disease, and Maffucci's syndrome.<unk>  must be differentiated from other diseases such as chondroma, enchondroma, osteochondroma, and osteosarcoma. Complications that can develop as a result of<unk>  are metastasis and recurrence. The prognosis of<unk>  correlates with the grade and stage of the lesion at the time of diagnosis.<unk>  is associated with a 5 year survival rate of 70%. The presence of grade 3 lesions are associated with a particularly poor prognosis. Biopsy is the gold standard test for the diagnosis of<unk> . Open biopsy is carried out for<unk> . The tumor is then staged based on Enneking system for<unk> . The most common symptoms of<unk>  include pain and swelling in the area of tumor. Patients with<unk>  usually appear lethargic and emaciated. Physical examination of patients with<unk>  is usually remarkable for palpable mass, tenderness and decreased range of motion. On x-ray,<unk>  is characterized by lytic lesion, intralesional calcification, endosteal scalloping, and cortical remodeling. On CT scan<unk>  is characterized by matrix calcification, endosteal calcification, cortical breach, and heterogenous contrast enhancement. On MRI,<unk>  is characterized by low to intermediate signal on T1, very high intensity in calcified portions on T2, and moderate to intense contrast enhancement on T1 contrast. Bone scan shows very hot uptake in all grades of<unk> . Chemotherapy and radiotherapy are indicated for<unk>  as adjuvant therapy or palliative treatment in surgically inaccessible areas. Surgery is the mainstay of treatment for<unk> . Adjunctive chemotherapy and radiation may be required. Recurrence rate depends on the grade of<unk> .
Chondrosarcoma
Fibrosarcoma
Chondroma
Osteoblastoma
Liposarcoma
Dermatofibrosarcoma
Synovial sarcoma
Chondromyxoid fibroma