Fig. 2

Radiologic appearance and morphological phenotypes of H3F3A mutant osteosarcomas. a Anteroposterior radiograph of the left wrist shows a lesion in the epi- and metaphysis of the distal radius (left). Histology revealed an osteoblastic osteosarcoma with pronounced nuclear atypia, brisk mitotic activity and a compact, extensive sclerosing osteoid matrix. b Lateral radiograph of the right knee shows a lesion in the distal femoral metaphysis with infiltration of the epiphysis and prominent extension into the soft tissue. The tumor was composed of pleomorphic, relatively plump and focally spindle-shaped tumor cells depositing osteoid in plaques (mixed osteoblastic/fibroblastic osteosarcoma). c Lateral radiograph of the right knee shows a lesion in the distal femoral meta- and epiphysis with subchondral extension and infiltration of the joint. The tumor (mixed osteoblastic/fibroblastic osteosarcoma) was predominantly composed of plump tumor cells producing coarse plaque-like osteoid. d Lateral radiograph of the right knee shows a lesion in the proximal fibula (caput fibulae). Histology revealed an osteoblastic osteosarcoma with highly pleomorphic tumor cells focally producing coarse and lace-like osteoid deposits. e Anteroposterior radiograph of the hip joint shows a lesion in the intertrochanter and subtrochanter region of the proximal femur. Histology revealed a mixed osteoblastic/fibroblastic osteosarcoma with coarse osteoid production. f X-ray imaging of the proximal tibia was not available in case 79,428. Histologically this bone lesion presented as osteosarcoma (mixed osteoblastic/fibroblastic subtype) with neoplastic bone production that was focally arranged in a coarse lace-like pattern. Foci with necrosis and dystrophic calcification were noted. White arrows indicate the corresponding lesion (a–e). Scale bars equal 50 µm (a–f)