Skeleton intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle. Cartilage is composed of specialized cells called chondrocytes that produce a large amount of extracellular matrix composed of Type II collagen (except Fibrocartilage which also contains type I collagen) fibers, abundant ground substance rich in proteoglycan, and elastin fibers. Cartilage is classified in three types, elastic cartilage, hyaline cartilage and fibrocartilage, which differ in the relative amounts of these three main components. Unlike other connective tissues, cartilage does not contain blood vessels. The chondrocytes are supplied by diffusion, helped by the
Chondrosarcoma themselves, both of which are directly linked to the propensity of the cancer to invade locally, and to spread widely to distant organs and sites in the body (called metastasis). Grade 1 chondrosarcoma grows relatively slowly, has cells whose histological appearance is quite similar to cells of normal cartilage, and have much less aggressive invasive and metastatic properties. Grades 2 and 3 are increasingly faster-growing cancers, with more varied and abnormal-looking cells, and are much more likely to infiltrate surrounding tissues, lymph nodes, and organs. Some, but not all, authorities and medical facilities assign a "Grade 4" to the most