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. Soft less frequent sites are other bones of the trunk, radius, ulna, foot, and hand (chondrosarcoma is commonly seen in the hand and less frequently in the trunk bones). Clinical and imaging data are more important than other tumors in the diagnosis of central chondrosarcoma. Cartilage tumors with the same histologic presentation can be benign or malignant and must be considered with reference to age, location, symptoms, imaging, bone scan, CT and other features. The preoperative diagnosis of central chondrosarcoma is often easy; however, the differential diagnosis involves a large number of tumors and tumor-like lesions. First, central chondrosarcoma must be differentiated from chondrosarcoma, especially the distinction between grade I central chondrosarcoma and borderline malignant chondrosarcoma. Chondrosarcoma occurs in children, stops growing in adulthood, and can remain unchanged for years unless a pathologic fracture occurs. Chondrosarcoma is painless, usually of moderate size, with no scalloped cortical bone, no interruption of cortical bone, and no soft tissue swelling. In short, chondromas often leave the cortical bone intact, except for small tubular bones located in the hand and foot. Because cartilage tumors of the hand are almost always benign, the diagnosis of central chondrosarcoma in this area must be made with caution and only when clinical, imaging, and histologic evidence of definite malignancy is present. Conversely, since chondrocytic tumors located in the trunk bone are often malignant unless other lesions have been demonstrated, the diagnosis of central chondrosarcoma in these sites should be thought of and extensive resection should be performed in suspicious cases. In multiple chondrosarcomas and chondromatosis, chondrosarcomas can grow to considerable size and continue to grow in adulthood, characterized by proliferative active histologic manifestations. Since the chance of their transformation into central chondrosarcoma is quite high, the possibility of central chondrosarcoma should be suspected in adulthood when the symptoms and images of chondrosarcoma change, and biopsy should be performed immediately to clarify the diagnosis. Typical (chondroblast type) osteosarcoma occurs in childhood and central chondrosarcoma is rarely present before puberty. Even in adults, the imaging and gross pathology of these two tumors are different, but the main difference lies in the histology. In osteosarcoma, osteogenic differentiation and direct production of bone-like material by tumor cells can certainly be found even if the tumor cells are mainly chondroblasts, and the malignancy of chondrocytes (grade IV) is higher in osteosarcoma than in central chondrosarcoma. However, in some rare cases, differential diagnosis with limited biopsy specimens is difficult, if not impossible, and in such cases it is advisable to repeat the biopsy with more specimens and specificity before deciding whether to treat with chemotherapy. The gross pathology of mucinous fibroma of cartilage can be identical to that of central chondrosarcoma. Histologically, the central lobulated cells of mucinous fibroma of cartilage can be misdiagnosed as grade I or II central chondrosarcoma, but the infantile occurrence, imaging, and typical histologic features of mucinous fibroma of cartilage are available for differential diagnosis.