four different types of osteosarcoma were investigated : case 1 was an atypical osteoblastic osteosarcoma , case 2 a small cell sclerosing osteosarcoma , case 3 a well-differentiated parosteal osteosarcoma grade i , and case 4 a highly malignant anaplastic osteosarcoma .
C0206642
parosteal osteosarcoma
C0029463
malignant