Sarcoma [Disease/Finding] Osteosarcoma [Disease/Finding] N0000002678 Osteosarcoma 1022808 M0019439 Sarcoma, Osteogenic Osteosarcoma 21708004 A sarcoma originating in bone-forming cells, affecting the ends of long bones. It is the most common and most malignant of sarcomas of the bones, and occurs chiefly among 10- to 25-year-old youths. (From Stedman, 25th ed) C5534 Osteosarcoma Tumor C0029463 D012516 Neoplasms, Bone Tissue [Disease/Finding]