Extraskeletal masses are chondrosarcomas. Central chondrosarcoma is a chondrosarcoma that originates from within the bone. The main symptom is deep pain that is not intense and non-persistent. In the progressive stage of the tumor, large spherical extraosseous masses may form. There are distinct sites of predilection, in order of predilection, for the femur (especially proximal), pelvis, proximal humerus, scapula, and proximal tibia. The other bones of the trunk, the radius, the ulna, the foot, and the hand are the less frequent sites (chondrosarcoma is more common in the hand and less common in the trunk bones). Chondrosarcoma is a malignant tumor that originates from cartilage tissue. They are less common than osteogenic sarcomas. There are two types of tumors, primary and secondary, the latter can be malignant from chondrosarcoma and osteochondroma, which is one of the reasons for the later age of onset. The tumor is mostly seen in adults, rare under 30 years old, and the incidence gradually increases after 35 years old. It is more common in males than females. The central type occurs in the medullary cavity, the periosteal type occurs in the periosteum, and a few other tumors may occur in the soft tissue. The tumors are usually found in the long bones of the limbs and pelvis, but also in the vertebrae, sacrum, clavicle, scapula and foot bones. Most chondrosarcomas are secondary to benign cartilage tumors such as endophytic chondrosarcoma and osteochondroma. The types are more complex and sometimes cause diagnostic difficulties. According to the development process of the tumor, it can be divided into two types: primary and secondary. The former has early age of onset, high malignancy, rapid development and poor prognosis, while the latter is a malignant transformation of benign tumors such as osteochondroma and chondrosarcoma, with late onset, slow development and slightly better prognosis, accounting for 4% of chondrosarcomas. Central chondrosarcoma in the long bones usually originates from one end of the diaphysis or the epiphysis, and since the patient is usually an adult whose growth cartilage has disappeared, the tumor often invades the epiphysis and sometimes the joint; central chondrosarcoma originating from the middle part of the diaphysis is rare, and at the time of diagnosis, the tumor may have invaded 1/3, 1/2 or more of the entire long bones; central chondrosarcoma of the pelvis usually occurs in the area around the acetabulum (iliac bone, sciatic bone, or pubic bone); central chondrosarcoma of the shoulder is more likely to occur. Central chondrosarcoma of the pelvis is found in the periacetabular region (ilium, sciatic or pubic bone); central chondrosarcoma of the scapula is found in the rostral-articular glenoid region. Chondrosarcoma of the pelvis and scapula can also invade large portions of the bone.