Chondrosarcoma

A chondrosarcoma is a cancer that derives from the cells that create cartilage. Although they are quite rare, they make up about 30% of all cancers that affect the skeletal system, although they most commonly appear on the pelvis and shoulder. They can present at any time from childhood to old age. They are very difficult to treat as they are resistant to both radiation therapy and chemotherapy.
The symptoms of a chondrosarcoma are prosaic and include pain in the back or thighs, bladder dysfunction and edema. Many patients are asymptomatic. They are usually diagnosed when they are seen on X-rays or a CT Scan.
Chondrosarcomas are graded based on how fast the cells grow and how differentiated the cell types are. A stage 4 chondrosarcoma has almost certainly undergone metastasis with a very poor prognosis. The cancer usually metastasizes to the lungs.
Because of the rarity of the condition, any treatment is usually reserved for specialized hospitals that deal with sarcomas. Surgery is the usual treatment, and can include the removal of large amounts of bone. Because they do not respond well to follow up treatment, recurrence is common and further monitoring is necessary.
Chondrosarcoma at Wikipedia