Bone Pathology II Neoplastic Bone Lesions

1. Bone Pathology IINeoplastic Bone Lesions Richard Anderson, MD President, Associated Pathology Consultants, S.C. Edward Hospital & Elmhurst Memorial Hospital Clinical Instructor, Department of Pathology, UIC College of Medicine Chairman of the Board, Heartland Blood Centers UIC M2 Pathology - 2004

2. Bone-Forming Tumors • Benign • Osteoid Osteoma • Osteoblastoma • Malignant • Osteogenic sarcoma

3. Osteoid Osteoma • Signs/Symptoms: • Pain, characteristically more intense at night, relieved by NSAIA and eliminated by excision • Vertebral lesions may cause scoliosis • Age: • 10-30 years • Sex: • M > F (2:1) • Anatomic Distribution: • Nearly every location, most frequent in femur, tibia, humerus, bones of hands and feet, vertebrae and fibula • Over 50% of cases in femur or tibia • Metaphysis of long bones

4. Central radiolucent nidus with or without a radiodense center; surrounded by thickened sclerotic bone

6. Central hemorrhagic nidus surrounded by dense rim of sclerotic bone

7. Nidus contains interlacing network of osteoid and bony trabeculae with variable amount of mineralization, lying in vascular fibrous tissue

9. Osteoid Osteoma • Ancillary Testing: • N/A • Prognosis/Treatment: • Surgical excision is treatment of choice • Recurrence unlikely with complete excision

10. Osteoblastoma (Giant Osteoid Osteoma) • Signs/Symptoms: • Pain • Gait disturbances • Age: • 80% of patients < 30 years • Sex: • M >> F (3:1) • Anatomic Distribution: • Predilection for vertebral column • Metaphysis of long bones

11. Osteoblastoma (Giant Osteoid Osteoma) • Radiographic Findings: • Similar to osteoid osteoma, though much larger (up to 11.0 cm) • Gross and Microscopic Findings: • Similar to osteoid osteoma, though much larger nidus • Ancillary Testing: • N/A • Prognosis/Treatment: • Curettage followed by bone grafting • If incompletely removed, tumor may recur • Malignant change to osteosarcoma has been rarely reported

12. Osteogenic Sarcoma (Osteosarcoma) • Most frequent primary malignant bone tumor • Malignant cells must produce osteoid • Most tumors arise de novo, though others arise in the setting of: • Paget’s disease • Previous RT • Previous chemo (especially alkylating agents) • Fibrous dysplasia • Osteochondromatosis • Chondromatosis • Chronic osteomyelitis

13. Osteogenic Sarcoma (Osteosarcoma) • Signs/Symptoms: • Pain and swelling • Pathologic fracture is uncommon • Age: • Peak in 2nd decade with gradual decrease thereafter • Sex: • M > F • Anatomic Distribution: • 50% arise around the knee • Metaphysis of long bones

21. Osteogenic Sarcoma (Osteosarcoma) • Microscopic Findings: • Tumor cells produce osteoid or calcified osteoid • Osteoblastic, chondroblastic or fibroblastic types • Osteoclast-like giant cells may be present

26. Cartilage-Forming Tumors • Benign: • Chondroma • Osteochondroma • Chondroblastoma • Chondromyxoid Fibroma • Malignant: • Chondrosarcoma

27. Chondroma • Benign tumor of mature hyaline cartilage • Most within bone (enchondroma) • 2 syndromes characterized by multiple chondromas: • Ollier’s disease • Multiple enchondromas, usually unilateral • Maffucci’s syndrome • Multiple enchondromas associated with soft tissue hemangiomas • Both disorders have 25% risk of malignant transformation to chondrosarcoma • Enchondroma is the most common tumor of the bones of the hand

28. Chondroma • Signs/Symptoms: • Usually asymptomatic lesions; pain with pathologic fracture • Age: • Evenly distributed • Sex: • F > M • Anatomic Distribution: • 50% of lesions within small bones of hands and feet (mostly the phalanges)

29. Localized central lytic lesion surrounded by sharp rim of sclerosis; cortex usually not involved, though may be thin

32. Ollier’s disease

33. Composed of mature lobules of hyaline cartilage with foci of myxoid degeneration, calcification and endochondral ossification; may be quite cellular

34. Chondroma • Ancillary Testing: • N/A • Prognosis/Treatment: • Solitary chondromas of long or flat bones need no treatment • If fracture occurs, treat with curettage and bone grafting • Recurrence unusual

35. Osteochondroma • Most frequent benign bone tumor • Probably not a true neoplasm, but rather a tumor produced by growth of aberrant foci of cartilage on the surface of bone • Autosomal dominant disorder of osteochrondromatosis with risk of malignant transformation to chondrosarcoma

36. Osteochondroma • Signs/Symptoms: • Palpable mass of long duration • Pain from compression of regional structures • Age: • 60% of patients < 20 years • Average age 10 years • Sex: • M > F • Anatomic Predilection: • May occur in any bone; usually metaphysis of long bones (lower end of femur, upper end of humerus and upper end of tibia are most frequent)

37. Projection with cortex continuous with underlying bone; may be pedunculated; cartilaginous cap with frequent calcification

41. Osteochondroma • Ancillary Testing: • N/A • Prognosis/Treatment: • Surgical removal only for pain or cosmetic reasons • Lesion cured by complete removal; if recurs, suggests the lesion was probably a low grade chondrosarcoma

42. Chondroblastoma • Rare benign tumor • Most common primary epiphyseal tumor in children • Signs/Symptoms: • Local pain and swelling; tumors 1.0 to 7.0 cm • Age: • 2nd decade of life • Sex: • M > F • Anatomic Distribution: • Epiphysis of long bones • 40% in distal femur or proximal tibia

43. Chondroblastoma Lytic lesion of epiphysis with thin sclerotic rim; thinning without destruction of cortex

44. Cellular lesion with polyhedral chondroblasts; giant cells and areas of calcification may be seen; mitoses common

45. Chondroblastoma • Ancillary Testing: • N/A • Prognosis/Treatment: • Curettage with bone grafting • May recur locally if not completely removed

46. Chondromyxoid Fibroma • Rare benign tumor • Signs/Symptoms: • Pain and swelling • Age: • 2nd and 3rd decades • Sex: • M > F • Anatomic Distribution: • Metaphysis of long bones, though may abut the epiphysis • 30% of tumors in tibia

47. Eccentric, sharply defined radiolucency in metaphysis of long bones; may destroy cortex

48. Zones of cartilage, fibrous and myxoid tissue; few benign giant cells

49. Chondromyxoid Fibroma • Ancillary Testing: • N/A • Prognosis/Treatment: • En bloc resection • Curettage is associated with 25% rate of recurrence

50. Chondrosarcoma • Signs/Symptoms: • Local swelling and pain • Age: • Adulthood (60% between 30-60 years) • Rare in childhood • Sex: • M > F • Anatomic Distribution: • Trunk, shoulder girdle, upper ends of femur and humerus