Benign bone tumors

benign bone tumors

1. Benign Bone Tumors Dr. Debesh Shrestha 1 st year resident Department of Orthopaedics GMC

2. Bone tumors may be defined as a new growth arising in a bone or derived from cells which are components of skeletal tissue

3. Characters of benign tumor

4. Radiographic features

5. Benign bone tumors (Revised WHO classification 1994) Bone forming Osteoma Osteoid osteoma Osteoblastoma Cartilage forming Chondroma Osteochondroma Chondroblastoma Chondromyxoid fibroma

6. Fibrous tissue Fibroma Fibromatosis Giant cell tumors Benign osteoclastoma Vascular tissue Hemangioma Hemangiopericytoma Hemangioendothelioma

7. Other connective tissue Fibroma Fibrous histiocytoma Lipoma Other tumors Neurofibroma Neurilemmoma

8. Osteoid Osteoma 10% of benign bone tumors 2 nd – 3 rd decade of life M:F = 3:1 Lesion < 1.5 cm Predilection for lower extremity – femur/ tibia (half the cases) Malignant changes not documented

9. Clinical features Persistent pain Worse at night Relieved by NSAIDs (Aspirin) When lesion near joint– swelling, stiffness and contracture When lesion in vertebra– scoliosis

10. Diagnosis X-ray/CT Lesion is small (< 1.5 cm) central radiolucent nidus with surrounding bony sclerosis CT is the best to identify nidus Technetium bone scan Increased uptake by the nidus MRI Limited role Soft tissue changes and surrounding edema

11. Bony trabeculae surrounded by loose fibrovascular tissue

12. Treatment Medical treatment Percutaneous radiofrequency ablation Open surgical procedures

13. Medical treatment If patient is willing and symptoms adequately controlled NSAIDs Spontaneous healing in 3-4 years

14. Percutaneous radiofrequency ablation For lesions of pelvis and long bones CT guided core needle biopsy after which a radiofrequency electrode is inserted through the canula of the biopsy needle Temperature of tip -90 degrees for 6 mins Outpatient procedure Recurrence <10% Not indication for vertebral lesions and small bones of hands and feet (thermal injury)

15. Surgical management Curettage En bloc resection– low recurrence rate but rarely indicated in long bones (post operative fracture)

16. Burr-down technique Identify nidus by fluoroscopy Remove sclerotic bone overlying nidus by power burr Nidus removed using curet Cavity treated again with power drill to remove entire nidus Recurrence<10%

17. Osteoblastoma Giant osteoid osteoma Larger > 1.5 cm 3% of all benign bone tumors Young adults (10-25 years) M:F = 2:1 Site : Spine (most common), metaphysis / diaphysis of long bones, small bones of hands/feet

18. Clinical features Pain No night pain Not relieved by NSAIDs

19. Diagnosis X-ray Well demarcated osteolytic lesion May contain flecks of ossification Surrounding sclerosis (thin) CT scan: investigation of choice Radioisotope scan: increased uptake MRI : soft tissue and intraspinal extension

20. anastomosing bony trabeculae separated by loose fibrovascular stroma . 

21. Treatment Excision and bone grafting Local recurrence common Malignant transformation reported

22. Chondroma Benign lesions of hyaling cartilage Common Affects all age groups Any bone can be involved but mainly affects phalanges of the hands and feet Usually asymptomatic and discovered incidentally or after a pathologic fracture

23. Enchondromas : arise in the medullary cavity Periosteal / juxta -cortical chondromas : arise on the surface of the bone (rare)

24. Multiple enchondromatosis Ollier disease rare Multiple enchondromatosis Many cartilaginous tumors appear in the large and small tubular bones and in the flat bones

25. Maffuci syndrome Multiple enchondromatosis occuring in association with soft tissue hemangiomas Individual lesions are similar to solitary enchondromas They have a tendency to become malignant 25% of patients with Ollier disease are diagnosed with sarcomas by 40.

26. Diagnosis Radiography Benign appearing tumors Translucent Intralesional calcification– irregular (stippled/ punctate / popcorn) Small bones of hand hands and feet– considerable erosion and expansion of the overlying cortex

27. Long bones– deep endosteal erosion (>2/3 of the thickness of cortex) indicates a chondrosarcoma Associated soft tissue mass– indicates chondrosarcoma

28. Histology Consists of mature hyaline cartilage Proximally located enchondromas – hypocelluar ( hypercellularity / atypia in proximally located enchondromas indicates chondrosarcoma ) Enchondromas of hand, juxta -cortical chondromas and multiple enchondromatosis may be relatively hypercellular and mild atypia but still be benign

29. Treatment Solitary enchondromas observation and serial radiographs If asymptomatic and radiographically stable—no further intervention If symptomatic or lesion grows– extended curettage Recurrence is low

30. Multiple enchondromatosis More difficult Lesions are not treated individually Obvious deformities corrected by osteotomy Monitored indefinitely for malignant changes

31. Osteochondroma Common Development malformations rather than true neoplasms Originate within the periosteum as small cartilaginous nodules P roduced by progressive endochondral ossification of a growing cartilaginous cap

32. Growth of lesion parallels that of the patient and stops once skeletal maturity is reached Most lesions found during the period of rapid skeletal growth. Single lesion—90% Site– may involve any bone formed in cartilage usually found on metaphysis of long bone near the physis (distal femur, proximal tibia , proximal humerus )

33. Osteochondromas are of 2 types: Pedunculated (more common) Sessile Malignant degeneration– 1% for solitary osteochondroma and 5% for multiple osteochondromas

34. Rarely develop in a joint Trevor disease (dysplasia epiphysealis hemimelica ) refers to intra- articular epiphyseal osteochondroma

35. Clinical feature Asymptomatic mostly Discovered incidentally Mechanical symptoms Pathological fracture Neuropathies due to compression of nerve by tumor

36. Hereditary multiple exostoses Autosomal dominant Multiple osteochondromas in bones arising from osteochondral ossification Skeletal deformities and short stature Defect in EXT1/EXT2 genes

37. Diagnosis X-ray Eccentric bony outgrowth from metaphyseal region of long bone composed of cortical and medullary portions which are continuous with the cortex and medulla of the underlying bone Cap not visible Usually sufficient

38. Treatment Small asymptomatic lesions—observation Indications for surgical excision: Cosmesis Joint dysfunction Fracture Impingement of nerve, vessels, tendons Malignant change

39. Surgery Complete excision of osteochondroma including the perichondrium Recurrence if incomplete removal

40. Chondroblastoma Benign tumor of immature cartilage Occurs primarily in the epiphysis Usually proximal humerus , femur or tibia Age– around the end of growth period or in early adult life Male predilection

41. Clinical feature Constant pain over the joint Tenderness over the adjacent bone

42. Diagnosis Rounded, well demarcated radiolucent area in the epiphysis No central calcification Sometimes the lesion extends across the physeal line Occasionally the articular surface is breached

43. Large collection of chondroblasts surrounded by immature fibrous tissue Scattered giant cells seen

44. Treatment Lesion removed after the end of growth period options Marginal excision (less satisfactory) 2. Curettage 3. Alcohol or phenol cauterization Recurrence if incomplete resection

45. Fibrous dysplasia Developmental disorder in which areas of trabecular bone are replaced by cellular fibrous tissue containing flecks of osteoid and woven bone. May affect one bone (mono- ostotic ), one limb ( monomelic ) or many bones ( polyostotic ) Sites– proximal femur, tibia, humerus , ribs and cranio -facial bones

46. Clinical features Small single lesion asymptomatic Large mono- ostotic lesions– pain or pathological fracture Polyostotic disease– pain, limp, bony enlargement, deformity or pathological fracture Albright syndrome = fibrous dysplasia + cafe-au- lait spots + precocious puberty in girls Malignant transformation– 0.5% in mono- ostotic lesion and upto 5% in Albright syndrome

47. Diagnosis X-ray Radiolucent cystic areas in the metaphysis or shaft The lucent areas have a hazy or ground glass appearance (due to fibrous tissue) Weight bearing bone may be bent – shepherd’s crook deformity of proximal femur

48. Osteoid trabeculae  that are narrow, curvilinear or irregularly-shaped are arranged haphazardly in a background of dense fibroblastic stroma .

49. Treatment Small lesions– no treatment Large,painful and fracture– curet and graft Recurrence may occur

50. Giant cell tumor 5% of all primary bone tumors. Uncertain origin appear in mature bone Hardly seen before closure of nearby physis Most common site: distal femur, proximal tibia, proximal humerus , distal radius

51. Clinical features Young adult Pain at end of long bone Slight swelling (sometime) Hx of trauma not uncommon Pathological # 10-15% O/E: palpable mass with raised local temperature

52. Xray Radiolucent area eccentrically at end of long bone, bounded by sub- chondral plate Center has soap bubble appearance due to ridging of surrounding bone Cortex is thin and ballooned Appearance of cystic lesion in mature bone extending upto subchondral plate is characterstic .

53. Detail staging and extent of tumor can be done by CT and MRI (imp to establish if articular surface has been breached or not) Biopsy ; essential

54. Potential to transform into osteosarcoma Rarely metastasize into lungs

55. numerous  multinucleated giant cells  scattered in a background of  uniform mononuclear cells

56. Treatment Benign histology tumor: Curettege and stripping of cavity with burrs and gouges followed by swabing with hydrogen peroxide Aggressive: excision followed by bone grafting or prosthetic replacement.

57. Chondromyxoid fibroma May occur any bone, more on bone of lower limb Seen in adolescent and young adults Discovered on accident or after pathological # Malignant change rare

58. Xrays Very characteristic Rounded or ovoid radiolucent area placed eccentrically in metaphysis In children extend upto physis Endosteal margin may be scalloped but always bounded by dense zone of reactive bone extending tongue like towards diaphysis Cortex asymmetrically expanded

59. Patches of myxomatous tissue + island of hyaline cartilage + area of fibrous tissue

60. Treatment Excision Curettage followed by autologous bone grafting Risk of recurrence present Care taken to prevent damage to physis or nearby joint.

61. Simple bone cyst a ka solitary cyst or unicameral bone cyst Appear in childhood. Metaphysis of long bone: mostly in proximal humerus or femur It is not a tumor, Heal spontaneosly Never seen in adults. Discovered after pathological # or incidental finding on xray .

62. Xray Well demarcated radiolucent area in metaphysis often extending upto physeal plate Cortex may be thinned and bone expanded. Needle inserted into cyst on x-ray control; straw colored fluid filled will be withdrawn

63. Treatment Asymptomatic lesion can be left alone but cautioned to avoid injury Active cyst: aspiration of fluid and injection of 80-160mg methylprednisolone or autologous bone marrow If cyst enlarging with pathological #: clean cavity by curettege and packed by bone chips Recurrence with need of more than one surgery.

64. Aneurysmal bone cyst At any age ,more on young adults Any bone, more on long bone metaphysis Arises spontaneously or after degenaration or hemorrhage in some other lesion. Pain is most common complain Large cyst may cause visible or palpable swelling of bone . Malignant transformation does not occur

65. Xray Well defined radiolucent cyst Trabeculated and eccentrically placed In growing tubular bone, vertebrae and flat bones In adult may confuse with GCT Marked ballooning of bone end

66.   large cystic spaces separated by septa containing giant cells and spindle cells . The spaces may be filled with blood and lack an endothelial lining

67. Treatment Thoroughly curetted and packed with bone graft Recurrence common as graft resorbed In recurrence: packing with methylmethacrylate cement may be effective Occasionally heal spontaneously.

68. Osseus Hemangioma Consists of vascular channels (capillary/venous/cavernous) Usually middle aged patients Spine- common site Asymptomatic / back ache Treatment– embolization followed by operation Coarse vertical trabeculation “ corduroy appearance”

69. References Campbell’s operative orthopaedics Apley’s system of orthopaedics and fractures Turek’s orthopaedics applications and their applications www.webpathology.com www.radiologyassistant.com

70. THANK YOU