Radiology of Bone Tumours

Property of Department of Orthopaedics, Faculty of Medicine, University of Zagazig

1. Radiology of B one T umors By Tarek A. ElHewala Lecturer of Orthopaedic Surgery Faculty of Medicine – Zagazig University

2. (1) Location of the lesion (2) Extent of the lesion (3) What is the lesion doing to the bone? (4) What is the bone doing to the lesion? (5) Hint as to its tissue type / matrix X-rays - the question need to ask:

3. A. Location Location and age of patient most important parameters in classifying a primary bone tumor. Simple to determine from plain radiographs.

4. Location

5. EPIPHYSEAL Chondroblastoma Clear cell chondrosarcoma Giant cell tumor Aneurysmal bone cyst Geode ( subchondral cyst) Infection Eosinophilic granuloma Location in Longitudinal Plane DIAPHYSEAL Adamantinoma Leukemia, Lymphoma, Reticulum cell sarcoma Ewing sarcoma Metastasis Osteoblastoma / osteoid osteoma Nonossifying fibroma METAPHYSEAL Nonossifying fibroma (close to growth plate) Chondromyxoid fibroma (abutting growth plate) Solitary bone cyst, ABC, GCT Osteochondroma Brodie abscess Osteogenic sarcoma, chondrosarcoma

6. Location in Transverse Plane Central: Enchondroma Eccentric: GCT, CMF, osteosarcoma Cortical: osteoid osteoma , NOF Parosteal : osteochondroma , parosteal osteosarcoma

7. Specific Location BONE TUMOR COMMONEST SITE SBC Proximal humerus > prox. Femur ABC, GCT, Osteosarcoma Lowerend femur > upper end tibia Enchondroma Metaphysis of small bones of hand & feet Osteochondroma Distal femur> prox. Tibia > prox. Humerus Chondroblastoma Proximal humerus> prox femur Ewing’s Femur > fibula > tibia Adamantinoma Mandible > tibia Myeloma Vertebra Fibrous dysplasia Ribs > Upper femur > Tibia > lower femur Osteoid osteoma Femur > tibia Chordoma Sacrum > clivus ( spheno occipital) > anterior vertebral body Ivory osteoma Frontal sinus Chondromyxoid fibroma Tibia > femur Chondroblastoma Pelvis > femur Osteoblastoma Posterior spine

8. Cysts and cyst like lesions of bone

9. Patterns of bone destruction: Lytic Sclerotic B: What is the lesion doing to the bone? PERMEATIVE GEOGRAPHIC MOTHEATEN Poorly demarcated lesion imperceptibly merging with uninvolved bone Long zone of transition Areas of destruction with ragged borders. Less well defined / demarcated lesional margin Longer zone of transition Well-defined smooth / irregular margin Short zone of transition

10. Margin between tumor and native bone is visible on the plain radiograph. Slowly progressive process is “walled-off” by native bone, producing distinct margins . Rapidly progressive process destroys bone, producing indistinct margins . MARGIN

11. Radiographic Margins Margin types 1A, 1B, 1C, 2, and 3 least aggressive 1A, to most aggressive 3 Aggressive lesions destroy bone. Aggressiveness increases likelihood of malignancy. BUT, not all aggressive processes are malignant. AND, not all malignant diseases are aggressive.

12. Margins: 1A,1B,1C increasing aggressiveness A well circumscribed lesion with a narrow zone of transition

13. 1A: sclerotic margin simple cyst (UBC) enchondroma FD chondroblastoma GCT chondrosarcoma (rare) MFH (rare)

14. 1B: well-defined, non-sclerotic GCT enchondroma chondroblastoma myeloma, metastatsis CMF FD chondrosarcoma MFH

15. 1C: lytic, ill-defined margins chondrosarcoma MFH osteosarcoma GCT metastasis infection EG lymphoma

16. 2: “motheaten” myeloma, metastases infection EG osteosarcoma chondrosarcoma lymphoma Multiple scattered holes that vary in size & seem to arise separately

17. 3: “permeative” Ewing EG infection myeloma, metastasis lymphoma osteosarcoma Poorly demarcated from normal, numerous elongated holes/slots in cortex, run parallel to long axis of bone

18. Limited responses of bone Destruction : lysis ( lucency ) Reaction : sclerosis Remodeling : periosteal reaction Rate of growth determines bone response slow progression, sclerosis prevails rapid progression, destruction prevails B. Reaction of bone to tumor

19. Periosteal Reaction Periosteal reaction must mineralize to be seen on X ray ( 10 days – 3 weeks) Configuration of periosteal reaction Nature of inciting process Intensity Aggressiveness Duration

20. Periosteal Reaction Thick, uninterrupted long standing process, often non-aggressive stress fracture chronic infection osteoid osteoma Spiculated , lamellated aggressive process tumor likely

21. Codman Triangle periosteal reaction tumor advancing tumor margin destroys periosteal new bone before it ossifies Codman Triangle

22. Sunburst Appearance

23. C: Tumor Matrix “Matrix” is the internal tissue of the tumor Most tumor matrix is soft tissue in nature. Radiolucent ( lytic ) on x-ray Cartilage matrix calcified rings, arcs, dots (stippled) enchondroma , chondroblastoma , chondrosarcoma Ossific matrix osteosarcoma

24. Osteochondroma Exostosis : well defined bony projection growing away from physis Cartilage maybe calcified if lesions are large / malignant change

25. Osteoid osteoma Nidus : a tiny radiolucent area If in diaphysis  surrounded by dense bone and thickened cortex Metaphysis  less cortical thickening Double density sign on bone scan – increased uptake in nidus and decreased uptake in reactive sclerotic zone (also seen in Brodie’s abcess ) Lytic nidus surrounded by sclerotic bone in CT Centre of nidus may be calcified

26. Well demarcated osteolytic lesion sometimes containing flecks of calcification Less reactive bone than osteoid osteoma Bone scan - intense activity Osteoblastoma

27. Cystic radiolucency on the diaphysial side of the growth plate Cortex may be thinned and bone expanded with well defined thin sclerotic margin May have pseudo- loculated appearance secondary to irregular cortical thinning and thin septal ridges Falling fragment sign typical and the lesion is never wider than epiphysial plate Bone scan cold or minimal activity unless fractured Simple bone cyst

28. Gross honey comb lesion Often eccentrically placed Does not extend to the joint (unlike GCT) Warm to hot on bone scan Aneurysmal bone cyst

29. Usually well defined geographic lytic lesion in the epiphysis/ metaphysis extending up to the joint surface without marginal sclerosis Junction with normal bone often poorly defined Cortex thinned and sometimes ballooned Bone scan warm to hot Giant cell tumor

30. Fibrous cortical defect Margin well defined, sometimes scalloped and often sclerosed

31. Geographic Well marginated Multilocular appearance Inter cortical osteolysis - single or multiple bubble like areas Non-ossifying Fibroma

32. Ground glass appearance typical Shepherds crook deformity of proximal femur Variable appearance with expansion of cortex Fibrous Dysplasia

33. Scalloped erosions on endosteal surface May have flecks of calcification Enchondroma

34. Rounded or oval rare area Usually eccentric ally placed May cross the growth plate Sharp outline and sclerotic rim Scalloped margin and thin cortex Chondromyxoid fibroma

35. Well defined area of rarefaction eccentrically placed in the epiphysis or across the growth plate No reaction in surrounding bone 50% show central calcification, 50% show linear periosteal reaction Bone scan increased uptake at margins Chondroblastoma

36. Multiple loose bodies Synovial Chondromatosis

37. Large osteolytic lesion in the midline May contain flecks of calcification Marked bone destruction Chordoma

38. Diffuse osteopenia with multiple osteolytic lesions dispersed throughout skeleton. Brown Tumor

39. Characteristic honey comb appearance in diaphysis Cortical thinning with expansion Adamantinoma

40. Vertical striations without bone expansion and coarse trabecular appearance (corduroy appearance) Hemangioma

41. Mottled lytic defect usually no sclerotic rim May destroy cortex Usually endosteal or periosteal reaction Lesions in flat bones and ribs appear punched out May appear loculated due to sparing of large trabeculae Spinal lesions- collapse (vertebra plana ), which may heal Eosinophillic granuloma

42. Mottled or moth eaten lesion diffusely involving bone Lytic destruction common, often the cortex is perforated Onion skin appearance - layers of periosteal new bone are said to be characteristic May form Codman’s triangle Ewing’s sarcoma

43. Variable with combination of bone destruction and bone formation Sun ray spicules / sun burst appearance and Codman’s triangle may be evident Cortical breach common Adjacent soft tissue mass Joint space rarely involved 25% Lytic 35% Sclerotic 40% Mixed Telangiectatic type- purely lytic Osteosarcoma

44. Variable appearance with 60 - 70% have calcification and 50% have sub periosteal new bone May be a large cystic lesion with cortical destruction and central calcification, endosteal scalloping and cortical expansion; annular, punctate or comma shaped calcification Chondrosarcoma

45. Bone often mottled or moth eaten with extension into soft tissue Osteolytic lesion may be surrounded by reactive bone Destructive appearance radiologically Usually little periosteal reaction Fibrorosarcoma

46. METASTATIC BONE DISEASE Osteolytic commonest - cortical destruction with little or no periosteal reaction; Lungs, Kidney, Adrenal, Thyroid, Uterus Osteoblastic deposits – Prostate, Bladder, Testis, Breast and Bowel secondaries . Also carcinoid lung tumors, lymphoma Mixed- Breast, Lung, Ovary, Cervix Lymphoma deposits may resemble prostatic deposits, i.e. sclerotic secondaries Lytic , expansile , with soft tissue mass- RCC, thyroid X-Ray- at least 50% loss of bone to produce lysis on X-ray, Loss of single pedicle produces a “winking owl sign”. CT scan, MRI

47. Osteolytic bone metastases: breast carcinoma shows multiple osteolytic bone lesions.

48. Osteoblastic bone metastases

49. Mixed pattern bone metastases:

50. Early - vague mottled lucent areas Diffuse destructive lytic lesion with little periosteal reaction Usually combination of patchy sclerosis and mottled destruction Hogkins disease - typical appearance of ivory vertebrae Lymphoma

51. May be generalised decrease in bone density Multiple punched out defects Little bony reaction around lesions Solitary lesion = plasmacytoma ; multilocular expanding lytic lesion in a red marrow area Frequently cold on bone scan Myeloma

52. Thank You