Bone & Joint Tumors

1. Bone & JointTumors

4. Periostal reactionsResponse to RAPIDLY growing lesions • Spiculated "hair-on-end" • Onion-skinning

5. Codman's triangle

6. Periostal reactionsResponse to SLOW growing lesions focal cortical thickening

7. I. Cartilaginous Tumors • Osteochondroma • Solitary Enchondroma • Chondrosarcoma

8. Osteochondroma • Osteocartilaginous exostosis • Most common benign tumors or tumorlike lesions of bone, • In almost any bone preformed in cartilage, particularly long tubular bones, • Presents as a solitary cartilage-capped bony outgrowth protruding from the bone surface near the metaphysis.

9. The most common location of an osteochondroma is in the region of the knee, • particularly the lower metaphysis of the femur or the upper metaphysis of the tibia. • occasionally in a flat bone • such as a rib, clavicle, ilium, or vertebra.

10. Pathology • A sessile or stalked, cartilage-capped, bony protusion which extends from the metaphysial region • Microscopically • bony protusion • a cap of mature cartilage

12. bony protusion • a cap of mature cartilage

13. Solitary Enchondroma • Central Chondroma • Composed of mature hyaline cartilage • Develops in the medullary cavity of a single bone • Third to sixth decades of life • average age : between 30 and 40 years.

14. The most common location is in the bones of the hand: • About one-third of all cases occur in the phalanges. • Sometimes: • the bones of the foot • long tubular bone (the humerus or femur) • pelvic bones • shoulder girdles.

15. Radiology: • A central, or slightly eccentric, well-circumscribed or "bubbly" radiolucent lesion, • finely or densely stippled with calcification.

17. Pathology: • Microscopically, small neoplastic cartilage cells with single small nuclei • May form lobules or facets • May be partially calcified

18. - lobules or facets • - partially calcified

19. Enchondromatosis (Ollier’s Disease)

20. Chondrosarcoma • A malignant cartilaginous tumor • The third to sixth decades of life (average age of 45 years) • Slightly more common in males than females

21. Chondrosarcoma may originate in the medullary cavity (central chondrosarcoma) • about 75% of cases or by malignant transformation of a preexisting enchondroma particularly in patients withenchondromatosis, • May originate in a juxtacortical location (peripheral chondrosarcoma) by sarcomatous change in the cartilage cap of an osteochondroma.

22. Location: • flat bones of the pelvis • the large limb bones • femur  25% • humerus • the ribs

23. Radiology: • Radiolucencies (irregular or circular or bubbly) • Calcification (granular or lobular radiopaque areas) • Destruction of the inner cortex, • Enlargement of bone contours, • Focal periosteal reaction, • Penetration of the cortex.

24. Chondrosarcoma

25. Chondrosarcoma

26. Chondrosarcoma

28. Microscopy • a lobular cartilaginous architecture, • highly cellular, • more than one nucleated cell per lacuna, • occasionally reveals tumor giant cells or clear cells, • with increasing grades of malignancy, has marked variation in nuclear and cellular size and shape.

29. Chondrosarcoma

30. II. Bone-Forming Tumors - Osteoid Osteoma - Osteoblastoma - Osteogenic Sarcoma

31. Osteoid Osteoma • A distinctive, small (<2 cm), solitary, benign, tumorlike lesion of bone • It is composed of osteoid tissue intermixed with woven bone and surrounded by reactive bony sclerosis. • Osteoid osteoma most often occurs in children and young adults. • A frequent presenting symptom of this condition is night pain, often relieved by aspirin, with localized tenderness in the painful area.

32. Osteoid osteoma is commonly located in a femur or tibia, • Radiology: • A representative x-ray picture • An osteoid osteoma shows a well circumscribed, small, round or oval, radioluscent or radiodense lesion (the nidus) • May be located in or near the cortex and surrounded by densely sclerotic bone.

33. Osteoid Osteoma

34. Microscopy • The nidus: • narrow trabeculae of osteoid or newly formed bone produced by osteoblasts + vascularized stroma • surrounded by a sclerotic mature bone.

35. Osteoid Osteoma

36. Osteoblastoma • Osteoblastomas are larger (> 2 cm) than osteoid osteomas • Mainly osteolytic • do not evoke reactive bone sclerosis • Higher recurrence rate (~10%) • Characterised by immature osteoid production • Commonly in the cancellous bone of the spine (posterior elements) and skull

37. Osteogenic Sarcoma • Osteosarcoma: a malignant tumor of bone • Most common primary bone tumor after myeloma

38. In young people under 20 years of age • Male / Female : 2/1 • Peak beyond 40 years of age: • Secondary to preexisting disease • Paget's disease (Paget's sarcoma) • Previous radiation (irradiation sarcoma) • Other conditions

39. Osteosarcoma may occur in any bone • The most frequent location is near the knee (~50-60% of cases) • most commonly in the distal end of the femur • the upper end of the tibia, • upper end of the humerus, • pelvis, • upper end of the femur. • Bone-forming cells produce alkaline phosphatase • The serum alkaline phosphatase is markedly elevated in many patients with osteosarcoma.

40. Radiology of a long bone usually show a large, ill-defined tumor. • The bone-producing (osteoblastic) lesion is located in the medulla near the metaphysis • Lifts up the periosteum (periostal reaction) • often producing "Codman's triangle", an angle between the outer cortex and the elevated periosteum, • Sun-rays pattern • Less common : • destructive (osteolytic) lesions with a "moth eaten" appearance of the cortex.

41. Osteosarcoma

42. Osteosarcoma Osteosarcoma

43. Osteosarcoma

45. Osteosarcoma: Lung mets

46. Microscopy • Proliferating malignant spindle- cell stroma • Osteoid or immature bone

47. Osteosarcoma

48. Osteosarcoma

49. III.Tumors of Other or Unknown Histogenesis • Ewing’s sarcoma • Giant Cell Tumor

50. Ewing's Sarcoma • A malignant, small, round-cell tumor of bone • Composed of uniform, densely packed, tumor cells with round nuclei and indistinct cellular borders • The histogenesis of Ewing's sarcoma remains controversial