1. 1 © 2015, Elsevier Inc., Heymann, Bone Cancer, Second Edition Chapter 32 Imaging of Bone sarcomas

2. 2 © 2015, Elsevier Inc., Heymann, Bone Cancer, Second Edition FIGURE 32.1 (A) Lateral radiograph of the femur with an aggressive, destructive osteoid producing lesion with associated ossification of only the raised edge of the periosteum inferiorly at the right of the image, creating a Codman’s triangle appearance in a patient with an osteosarcoma. (B) Frontal radiograph of the tibia-fibula with sunburst periosteal reaction involving the proximal fibular diaphysis with periosteum radiating outward like rays of the sun, and this was another case of osteosarcoma. (C) Lateral radiograph of the knee with a lytic lesion in the distal femoral diaphysis with surrounding sclerosis and associated multilamellated, or multilayered, periosteal reaction which is best demonstrated anteriorly. This was related to osteomyelitis.

3. 3 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.2 Coned down radiograph of the distal femoral diaphysis with a lytic, permeative pattern of destruction and ill- defined margins, a sign of an aggressive underlying bony process. This patient had osteomyelitis.

4. 4 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.3 (A) Frontal radiograph of the right shoulder with fluffy, cloud-like osteoid mineralization of an osteosarcoma overlying the lateral inferior scapula. Contrast that with with the classically described “rings and arcs” chondroid mineralization of an enchondroma seen in the proximal humerus on a frontal radiograph of the left shoulder in (B).

5. 5 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.4 Coronal T1-weighted image of the left humerus with normal high signal (bright) fatty marrow inferiorly with an abrupt transition to an abnormal intermediate signal (relatively darker) marrow more superiorly, and this demonstrates well how reliable MRI is to show marrow abnormalities. This was an osteosarcoma.

6. 6 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.5 (A) Oblique radiograph of the foot with some osseous hypertrophy at the inferior calcaneus with adjacent soft tissue thickening. Mineralization of the soft tissue thickening is difficult to appreciate on the radiograph. (B) Corresponding axial CT image of the foot which nicely demonstrates chondroid mineralization in the soft tissue with a classic rings and arcs pattern. This was a chondrosarcoma in an unusual location.

7. 7 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.6 Frontal whole body image from a Tc-99m MDP bone scan with increased activity in the proximal left femur, which corresponded to a patient’s primary osteosarcoma. Physiologic activity is present in the growth plates of this skeletally immature patient and also in the kidneys and bladder. No abnormal foci of increased activity was noted on this bone scan to suggest metastatic disease.

8. 8 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.7 This figure shows a fused frontal image from a PET/CT with increased metabolic activity corresponding with lymph nodes in the left pelvis and more subtle increased activity corresponding with lesions in the right iliac bone, acetabulum, lumbar spine, and mid-left femur in this patient with multifocal Ewing’s. Contrasted with the Tc-99m MDP bone scan, PET/CT allows for better localization of abnormal hypermetabolic osseous and soft tissue lesions because of the routine use of fused images.

9. 9 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.8 (A) Frog leg view of the left femur with a lytic, permeative appearance involving the distal portion of the visualized femoral diaphysis. Corresponding pelvic and thigh coronal T1 and T2 MRI images in (B) and (C) respectively show the extent of marrow involvement with a large area of abnormal decreased T1 signal and increased T2 signal extending from the left femoral neck to the distal diaphysis. Note the additional lesions with similar signal characteristics in the proximal right femoral diaphysis and right acetabulum in this patient with multifocal Ewing’s.

10. 10 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.9 Frontal (A) and lateral (B) radiographs of the left knee demonstrating an osteoid producing lesion in the distal femoral metaphysis with aggressive periosteal reaction seen on the lateral radiograph anteriorly. The correct diagnosis of osteosarcoma was suggested prospectively based on this radiographic appearance. Corresponding T1-weighted coronal (C) and axial (D) images show the intermediate signal mass in the distal femur with destruction of the cortex medially seen on the axial image. Note again that the coronal image demonstrates how the entire length of the femur and adjacent joints must be imaged to look for skip metastases, which this patient did not have.

11. 11 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.10 Frontal (A) and oblique (B) radiographs of the tibia-fibula with an expansile, lytic lesion in the proximal fibula with associated cortical destruction. (C) shows an associated T1 coronal MRI image demonstrating an intermediate T1 signal mass with cortical destruction in the proximal fibula. Corresponding axial T2-weighted image in (D) shows classically described fluid-fluid levels within this lesion, and a post-contrast axial fat saturation image in (E) demonstrates soft tissue enhancement throughout this mass. Cortical destruction and soft tissue mass are again features favoring telangiectatic osteosarcoma over aneurysmal bone cyst, and this turned out to be a telangiectatic osteosarcoma.

12. 12 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.10 Frontal (A) and oblique (B) radiographs of the tibia-fibula with an expansile, lytic lesion in the proximal fibula with associated cortical destruction. (C) shows an associated T1 coronal MRI image demonstrating an intermediate T1 signal mass with cortical destruction in the proximal fibula. Corresponding axial T2-weighted image in (D) shows classically described fluid-fluid levels within this lesion, and a post-contrast axial fat saturation image in (E) demonstrates soft tissue enhancement throughout this mass. Cortical destruction and soft tissue mass are again features favoring telangiectatic osteosarcoma over aneurysmal bone cyst, and this turned out to be a telangiectatic osteosarcoma.

13. 13 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.11 (A) An oblique plain film of the tibia-fibula with osteoid mineralization at the medial aspect of the proximal tibial diametaphyseal region. Note the lucent line, or cleavage plane, between the osteoid mineralization and adjacent tibial cortex. This was a parosteal osteosarcoma. (B) shows a corresponding axial CT image, which shows a narrow zone of attachment of mass to the adjacent tibial cortex with an adjacent cleavage plane.

14. 14 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.12 (A) A frontal radiograph of the left hip with cortical thickening along the proximal femoral diaphysis with associated saucerization of the superficial cortical surface with aggressive, very subtle hair-on-end periosteal reaction extending medially from the cortex. This was a periosteal osteosarcoma. Corresponding axial T1 and T2 images in (B) and (C) respectively show associated mild signal abnormality in the medullary canal, but it is not in direct continuity with the primary tumor suggesting that this represents reactive marrow changes as opposed to true marrow invasion. Lack of marrow invasion was confirmed pathologically at resection.

15. 15 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.13 (A) A frontal radiograph of the proximal tibia with a mixed lytic and sclerotic lesion in the proximal tibial metadiaphyseal region. There is associated cortical thinning laterally. Although the appearance resembles fibrous dysplasia on the radiograph, corresponding coronal T1-weighted MRI image (B) shows associated cortical destruction laterally, which is not a feature of fibrous dysplasia and therefore suggests the diagnosis of low-grade central osteosarcoma, which was confirmed at pathology.

16. 16 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.14 A frontal pelvic radiograph (A), axial CT image (B), axial T1 (C) and T2 (D)-weighted MRI images which demonstrate a chondrosarcoma arising in an osteochondroma. Note the complete loss of a normal cortical shell, widespread chondroid calcification, and associated infiltration of the medullary cavity which is best seen medially, all suggesting malignant degeneration. There is corroborative evidence with a cartilage cap measuring greater than 2cm.

17. 17 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.15 (A) A frontal radiograph of the pelvis with a vague lytic lesion in the right acetabulum. Corresponding coronal T1-weighted MRI image (B) shows an extensive intermediate signal T1 lesion involving the entire right acetabulum and iliac bone. Corresponding coronal T2-weighted image (C) shows corresponding lobular areas of high T2 signal, suggestive of cartilage. This was a low-grade chondrosarcoma.

18. 18 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.16 Frontal pelvic (A) and right hip frog leg view (B) radiographs with a lytic lesion in the right acetabulum. Corresponding coronal T1-weighted MRI image (C) shows an intermediate signal lesion in the right acetabulum with cortical breakthrough and soft tissue extension medially and inferiorly. Corresponding coronal T2-weighted image (D) shows sharp demarcation between lobulated high T2 signal representing cartilaginous tissue in the acetabulum laterally and intermediate T2 signal representing a high-grade sarcoma in the medial acetabulum with associated cortical destruction and soft tissue extension. This was a dedifferentiated chondrosarcoma with spindle cell sarcoma.

19. 19 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.17 (A) A lateral radiograph of the sacrum with sclerosis of the distal sacrum and coccyx. Notice the pre-sacral region is not well evaluated on radiograph when compared to subsequent sagittal T1 (B), post-contrast T1 (C), and T2 (D)- weighted MRI images which demonstrate a mass arising from the sacrococcygeal region with osseous destruction and anterior extension into the soft tissues. There is heterogeneous increased signal on pre-contrast T1- and T2-weighted images with post- contrast enhancement. This was a chordoma.

20. 20 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.18 (A) A sagittal T1-weighted MRI image with an intermediate signal marrow replacing lesion in the S3 vertebral body. Corresponding sagittal CT image (B) shows vague sclerosis in the S3 vertebral body without cortical destruction. This patient had no history of malignancy, and the clinical decision was made to forego biopsy with a working diagnosis of benign notochordal cell tumor. Appropriate management in this case is serial follow-up with imaging.

21. 21 Copyright © 2013 Elsevier Inc. All rights reserved. FIGURE 32.19 Frontal (A) and lateral (B) radiographs of the tibia-fibula with overlying cast demonstrating lytic, linear lesions which are primarily cortically based extending over a length of the mid-tibial diaphysis. More superiorly, it has somewhat of a soap-bubbly appearance. This was an adamantinoma in a patient who presented with a pathologic fracture.