This document discusses osteosarcoma and giant cell tumor. It provides information on the location, causes, symptoms, investigations, classification, treatment and prognosis of osteosarcoma. It is a highly malignant bone tumor that most commonly affects teenagers. Treatment involves neoadjuvant chemotherapy, surgery (limb salvage or amputation), and additional chemotherapy. Giant cell tumor is a benign bone tumor that typically affects young adults near the epiphysis. Treatment focuses on curettage with adjuvants like PMMA to reduce recurrence.

1. Topic : Osteosarcoma &
Giant Cell Tumour
Moderator – Dr. Mahesh
Presenter – Dr. Karthik M V

4. Based on location
• Diaphysis
- Ewings’s sarcoma
- Osteoid osteoma
- Fibrous dysplasia
• Metaphysis
- Osteosarcoma
- Osteochondroma
- ABC, SBC
• Epihysis
- GCT
- Chondroblastoma

5. Osteosarcoma
• Most common Non hematologic primary malignancy of bone.
• Most commonly in the second decade of life.
• The incidence is slightly higher in males.
• Characterised by production of osteoid by malignant cells

6. • Highly malignant tumour arising from primitive mesenchymal bone –
forming cells.
• Any bone can be involved, but M/C site are – distal femur, proximal
tibia, proximal humerus.
• M/c site for metastasis is Lungs via blood stream.

7. Etiology
• Radiation exposure
• Genetic predisposition
- Hereditary retinoblastoma ( RB gene mutation)
- Li-Fraumeni syndrome (p53 gene mutation)
- Paget’s disease of bone.
- Bloom’s syndrome

8. • Age - peak incidence is during second decade of life.
12-25 years
• Sex - Male : Female (3:2)

9. Skeletal distribution
• Distal femur
• Proximal tibia
• Proximal humerus
Metaphyseal (89%) > Diaphysis (10%) > epiphysis (1%)

10. • Progressive pain is the most common symptom
• Deep, firm, fixed mass.
• Skin over swelling shiny with prominent veins.
• The motion of the joint is unimpaired, until muscle if
infiltrated by tumour.
• Painless mass is seen in low grade osteosarcoma

11. • Decreased range-of-motion (ROM) and functional limitation are features of
delayed neglected cases.
• Local warmth, telangiectasia, dilated veins and a bruit on auscultation may
be observed particularly in aggressive tumors.
• Sudden increase in pain indicates hemorrhage in tumor

12. Classification
• PRIMARY OSTEOSARCOMAS
 Conventional /classic osteosarcoma (high grade, intra medullary)
 Low-grade intramedullary osteosarcoma
 Parosteal osteosarcoma
 Periosteal osteosarcoma
 High-grade surface osteosarcoma
 Telangiectatic osteosarcoma
 Small cell osteosarcoma.

13. • SECONDARY OSTEOSARCOMA
Occurs at site of another disease process.
More common > 50 years.
Most commonly a/w premalignant conditions like paget’s disease,
previous radiation exposure, osteogenic imperfecta.
Most common in flat bones & diaphysis of long bones

14. Post irradiation osteosarcoma
• 3.5 – 5% cases of osteosarcoma
• Childrens treated with radiation therapy at high risk
• Loss of 3p is most frequently noted
• Radiologically there tumors are highly radiodense and sclerotic
• Poor prognosis.

15. Conventional osteosarcoma
• These high grade tumour
• Intra-medullary location
• Break through the cortex and form a soft tissue mass.

16. • Before fusion of epiphysis
- Physeal plate is intact, acts as barrier
• After fusion of epiphysis
- Tumour may extend into epiphysis, but articular cartilage bars
spreading into joint.

17. Investigations
• Radiological
Plain X-rays
MRI
CT
Bone scan
• Laboratory- Serum ALP
• Biopsy
• Angiogram

18. X-ray
Sclerotic
Lytic Mixed (most
common)

19. Radiological
• Sclerotic osteosarcomas (30%)
• Osteolytic osteosarcomas (25%)
• Mixed pattern (45%)
• The classical radiologic appearance is an
intramedullary combined lytic and sclerotic
lesion with cortical breach and bone-matrix
formation.

20. • Radiographic features are seen at metaphysis
of long bone eccentric growing away from
medullary canal to extra skeletal region
• Fine lines of increased density, representing
newly formed bone spicules radiates right
angle to the shaft called as Sunburst
appearance
• Skip lesions may be seen

21. • Lifting of periosteum by rapidly growing mass produces the
characteristic reactive bone formation “Codman’s angle” (Codman’s
triangle).
• Extension of the tumor through the periosteum may result in a so-
called “sunburst” or “hair on end” appearance.

22. Periosteal reaction may appear as the characteristic Codman
triangle.
Extension of the tumor through
the periosteum may result in a so-
called “sunburst” or “hair on end”
appearance.

23. • MRI
MRI is the modality of choice for defining the intramedullary extent
and surrounding infiltration by the tumor
Level of resection, skip lesions
CT
CT chest to detect lung metastasis

24. • Laboratory
Serum ALP is used as prognostic marker.
• Angiogram
To detect vascularity of tumour
Relationship of vessel to tumour
• Bone scan
Screening of metastasis and skip lesions

25. Gross appearance
• Colour reflects components
- Fibrous : white
- Ossesous : yellowish white
- Cartilagenous : bluish white
• Necrotic foci and cyst like cavitations are seen in
rapidly growing tumours.

26.  Arise from multipotent mesenchymal cells
 Mixture of osteoid, fibrous, cartilaginous, necrotic,
hemorrhagic, cystic areas
 Destruction of cortex
7
GROSS PATHOLOGY

27.  Metaphyseal, Central.
 Extension into medullary cavity and subperiosteal extension.
 Restricted by periosteum and epiphyseal plate, but eventually crosses it
 Reactive periosteal new bone formation
 Metastasis –lungs
8

28. Microscopic appearance
• Tendency of the osteosarcoma to grow in around vessels
(angiocentric) giving an overall “basketweave” pattern to tumor

29. Treatment
• Sarcoma spread along the path of least resistance
• Surgery alone shows survival rate less than 20%
• Modern chemotherapy has increased survival rate upto 60-70%

30. Surgery
 The main goal of surgery is to safely and completely
remove the tumor.
 Historically –amputation.
 Over the past few years - limb-sparing procedures have become the
standard, mainly due to advances in chemotherapy and sophisticated
imaging techniques
 Limb salvage procedures now can provide rates of local control and
long-term survival equal to amputation.

31. Decision???
If the tumor can be removed safely while retaining a viable
extremity, a limb sparing procedure may be appropriate.
Ifmajor nerves or blood vessels are involved, or if
complete tumor removal results in significant loss of
function, amputation may be a better choice.
Patient’s age, desired level of function, cosmetic
preference and long-term prognosis must also be
considered.

33. • Intra-lesional = plane of dissection goes
directly through the tumour
• Marginal= plane of resection through reactive
zone (inflammatory cells, edema, fibrous
tissue)
• Wide excision = entire tumour with normal
tissue also removed
• Radical = entire tumour along with its
compartment removed.

35. Limb salvage surgery
• Indications :
 StageIA StageIIA & StageIIIA (All intracompartmental
tumours)with good response to pre-operative chemotherapy
 Skin should be uninvolved and free
 There should be feasibility of keeping acuff of normaltissue surrounding
the tumour
 Upper extremity lesions are more suitable for limb sparingsurgery
 Tumours with good pre-operative chemotherapy response

36. Contraindications for LSS
1. Major neurovascular involvement.
2. Pathological fractures
3. Infection
4. Skeletal immaturity
5. Extensive muscle involvement.

37. Reconstruction of bone defect done by
• Autologous bone graft
• Allograft
• Endoprosthesis (most common)- replacing the removed bone with a
metal implant
• Rotationaplasty
• Custom made prosthesis

39.  compromise between amputation and limb
salvage
 used for osteosarcomas of the distal femur and
proximal tibia
 It is a procedure where the neurovascular structures
and distal aspect of the limb (leg) are retained, and
re-attached to the proximal portion after the tumor
is removed
Rotationplasty

40.  For functional purposes, the distal segment is turned 180degrees so that the ankle joint
functions as a knee joint,
thus converting an above-knee to a below-knee amputation in order for prosthetic use
to be maximized

42. • Amputation provides definitive surgical treatment whenlimb
sparing is not aprudent one.
• Common amputations in malignanttumours:
– Proximal humerus : fore quarter amputation
– Distal femur : hipdisarticulation
– Proximal tibia : mid thighamputation
Amputation

43.  Amputation involves removal of the limb with a
safe margin between the end of the retained
portion and the tumor
 It should not be viewed as a
failure of treatment, but rather as
the first step towards patient’s
comfortable and productive life.

44. Indications
1.Grossly displaced pathologic fracture
2.Encasement of neurovascular bundle
3.Tumor that enlarges during preop chemo and is
adjacent to neurovascular bundle
4.Palliative measure in metastatic disease
5.If the tumor has caused massive necrosis,
fungation, infection, or vascular compromise.

45. Chemotherapy
• Multi agent chemotherapy
• Doxorubicin, cisplatin, high dose methotrexate, etoposide
• Pre operative chemotherapy 3-4 cycles given ( neoadjuvant
chemotherapy) f/b surgery and subsequent postoperative
chemotherapy (adjuvant chemotherapy)

46. Advantages of Neo-adjuvant chemotherapy
– It controls micro metastasis and improves survival rate.
– Chemotherapy makes limb salvage surgery easier.
– Decreases tumor size and vascularity.
– The response to Chemotherapy can be evaluated after surgery

47. • Radioresistant
• Chemotherapy increases the susceptibility of tissues to irradaition.
• Postoperative radiotherapy is indicated in positive or close surgical
margins
• Palliative radiotherapy used in metastatic or incurable patients for
alleviation of local symptoms.
RADIOTHERAPY

48. • A portion of
tumour is
implanted in to a
sarcoma survivor
and removed after
14 days.
• Sensitized lymphocytes
from survivors are
infused in to patient.
These cells selectively
kill the cancer cells.
Immunotherapy

49. Prognosis
• Extent of the disease
• Pts with pulmonary, or skip metastasis have poor prognosis
• Grade of the tumour
• High grade tumour have poor prognosis
• Size of the primary lesion
• Large size tumours have worse prognosis then small size tumours
• Secondary osteosarcoma: Poor prognosis

50. Paraosteal osteosarcoma
• Most common type of surface osteosarcoma.
• Rare, low grade malignancy arising on the surface
invading medullary cavity at a later stage
• Most frequent position is posterior surface of
distal femur f/b proximal end of humerus
• C/F – localised painless swelling, mechanical
interfere with joint

51. • Slow growing tumour may have cartilaginous cap
• Radiologically - large, dense irregular exophytic
mass attached to parent bone by a wide base.
• CT is required to determine the intramedullary
involvement and “wrapping around” tendency of
the bone tumor.

52. • The histopathological appearance irregular osteoid seams surrounded
by spindle cells and scattered innocuous fibroblasts.
• Treatment – wide surgical excision
• chemotherapy is not employed (low grade tumour)

53. Periosteal osteosarcoma
• Surface osteosarcoma involving diaphysis of long
bone.
• Seen in 2nd decade of life
• Tibial shaft is the commonly affected region
• Rather than wrapping around the bone; they
project into the soft tissue as well circumscribed
mass.
• Radiographically, the lesions without any
intramedullary extension.
• Treatment is similar to that of conventional
osteosarcoma

55. Telangiectatic osteosarcoma
• Malignant bone aneurysm, hemorrhagic
osteosarcoma.
• Aggressive, may present with pathological
fractures.
• malignant bone-forming tumor characterized by
large spaces filled with blood with or without
septa.
• Radiologically, it is a purely lytic lesion
• Periosteal reaction seen.
• Grossly the tumor has a cystic appearance with the
spaces filled incompletely with blood.
• Rx – Chemotherapy with surgical excision

57. Giant cell tumour (Osteoclastoma)
• First described Cooper 1818
• Benign local aggressive osteolytic neoplasm.
• Primarily affects skeletally mature young adults
• large numbers of osteoclast-like giant cells, distributed uniformly in sheets
of neoplastic ovoid mononuclear cells
• Propensity to locally re-occur

58. • Constitutes 5% of bone tumours
• Skeletally mature young adults are commonly affected and peak
incidence is seen around 20–45 years of age.
• Slightly more often seen in females(1:1.5).
• The tumor commonly originates from the epiphyseal scar near
metaphyseo-epiphyseal junction.
• While most GCTB are benign, they rarely metastasize into the lungs.

59. • The primary areas of involvement are ends of long bones commonly
the
Distal femoral condyles
Proximal tibial plateau
Styloid process of distal radius
Proximal humerus.

60. History and physical examination
• Commonly presents with swelling, limited range of
motion, and pain because of the tumour’s proximity to
joint space.
• Patient complains of deep pain that is not related to
injury.
• These symptoms usually arise in the knee since the
epiphysis of distal femur or proximal tibia is the site of
tumour in over 50% of cases.
• In some cases patients have no symptoms, often being
found incidentally or as a result of pathological fracture

61. • EGG SHELL
CRACKING sensation
may be present (
thinning of cortex)
• Limitation of joint movement
and pathological fractures –
usually a late feature
• Metastasis – 1-5% lungs

62. histopathology
• On gross it appears to be a red friable
lesion sometimes extending upto the
articular cartilage from metaphysis to
epiphysis.
• EARLY LESION – Homogenous , friable,
reddish, brown mass.
• LATE LESION- blood filled areas

63. Microscopy
• Round to polygonal mononuclear
cells and multinucleate osteoclast
like giant cells
• Giant cells are uniformly scattered
• There’s no correlation b/w
histological appearance and
biological behaviour

64. Radiographic
• Lytic lesion near epiphysiso-metaphyseal
• Expansile
• Eccentric or central
• Multiple septa traverses the interior
produces “ soap bubble” appearance
• Cortical thinning
• No sclerotic margin
• No periosteal bone formation

65. staging
• Multiple classification systems for giant cell tumour of bone have been proposed to help with
staging:
• The campanacci grading is the most common and stratifies based on clinical and radiological
appearances:

66. ENEKING’S STAGING

67. Treatment
• Aim is to maximize functional preservation while minimizing the
chance of recurrence
• Extended curettage and adjuvant therapy
• Adjuvants- chemical cytotoxic agents
- physical agents
- heat cauterization, cryosurgery, high speed burr

68. • Local adjuvants such as aqueous zinc chloride, PMMA, 5% Phenol, Argon
beam coagulation, or cryotherapy have been utilised to reduce recurrence.
• The most established treatment with satisfactory recurrence is with PMMA
and phenol
• Bone cement has a tumor kill effect by exothermic reaction
• Methotrexate and Adriamycin in the bone cement to augment cytotoxic
effect

69. • Advantages of cementing:
Cytotoxic (exothermic)
Radiographic detection of recurrence is easier—as a clear lucent line
around the cement.
Good structural support and early weight bearing.
• Disadvantages of cementing:
Non biological & doesn’t get incorporated
Degeneration and crushing of articular cartilage

70. • Embolization
Large and unresectable (spinal, sacral, pelvic) tumours
Reduces the size of tumour and pain
Pre op embolization in an attempt to reduce intra operative bloodloss

71. Newer treatment
• DENOSUMAB: Is a monoclonal antibody that works binding to RANKL,
stopping it from activating its receptor, RANK.
• This action results in inhibiting the function and recruitment of osteoclast
like cells
• Denosumab is primarily for patients with the following situations:
- When expecting significant morbidity from initial surgery.
- Local recurrence
- Poor surgical candidates
- High risk locations
• Dosage- 120mg s/c- Day 1,7,14 then monthly

72. • Wide local excision for larger tumors can be done
followed by reconstruction using
1. Megaprosthesis (provide mobility but prone to
loosening and late failure)
2. Arthrodesis (stability but immobility)
Total serum acid phosphatase can be used as a
tumor marker for monitoring response to the
treatment of GCT

77. • Eccentric
• Expansile
• Ephysis
• Egg shell crackling
• Extended Curettagre

78. RECURRENCE OF LESIONS
• Patient should have radiograph of the primary tumor site and
the chest at 3months interval for 2 years
• 6months interval for next 1year and annually thereafter

79. Prognosis
• The overall prognosis of a giant cell tumour of bone is good,
though local recurrence can vary widely.
• A GCT located near the spinal cord carries a poorer prognosis and
has a high rate of local recurrence.
• Studies have found that 50% recurrence in intralesional curettage
without a local adjuvant.
• As mentioned earlier with usage of adjuvants retrospective studies
have demonstrated 13 to 22% recurrence rates.
• Rarely GCT can undergo a malignant transformation, which often
has a poorer prognosis.

80. Differential diagnosis/variants
• Aneurysmal bone cyst
• Unicameral bone cyst
• Chondroblastoma
• Chondromyxoid fibroma
• Non ossifying fibroma
• Fibrous dysplasia
• Brown tumour of hyper parathyroidism

81. Aneurysmal bone cyst
• They are locally destructive, blood filled reactive
lesions of bone and are not considered to be true
neoplasms.
• Most commonly in proximal humerus, distal femur,
proximal tibia and spine.
• Vertebral lesions, accounting for 20% of cases
• Most occur in patients younger than 20 years with a
slight female predominance.
• Patients may present with mild to moderate pain
present for a few weeks to months
• Rapid growth may occur and sometimes mimic a
malignancy

82. • Radiographs reveal an expansile lytic lesion that elevates the periosteum
but remains contained by a thin shell of cortical bone.
• eccentrically located in metaphysis
• CT is particularly helpful in delineating the cyst in areas of complex
anatomy.
• MRI is particularly useful in differentiating unicameral and aneurysmal
bone cyst through the presence of a double-density fluid level and
intralesional septations.

83. Unicameral bone cyst
• Developmental or reactive lesion than a tumour.
• First 2 decades of life; 2:1 Male predominance
• M.C proximal humerus and femur, in adults ileum and
calcaneum.
• Active during growing period and spontaneously resolve in
adulthood unless a pathological fracture occurs.
• Plain radiographs show a centrally located purely lytic lesion
with well marginated outline which is diagnostic for unicameral
bone cyst.
• Occasionally a thin cortical fragment fractures and falls to base of
lesion “ fallen fragment sign”

84. • Usually present in the metaphysis and they are considered active if they are within 1 cm of
the physis and latent when they are closer to the diaphysis.
• UBC are filled with yellow clear serous fluid unless a pathological fracture causes
haemorrhage into the bone.

85. chondroblastoma
• A rare neoplasm, typically occurs in patients 10
to 25 years old.
• Male to female predominance is 2:1.
• The tumour has a predilection for the epiphyses
of long tubular bones.
• Patients present with progressive pain that may
mimic a chronic synovitis.
• Radiographic findings usually is a well
circumscribed lesion is usually centred in an
epiphysis of a long bone, it can also be located
in the apophysis, like greater trochanter with
surrounding rim of sclerosis.
• CT can be helpful in detecting subtle areas of
calcification not seen on xrays.

86. Chondromyxoid fibroma
• Is a rare lesion of cartilaginous origin
• Most commonly seen between ages of 10 to 30 years old.
• Any bone can be involved but most common is proximal tibia.
• Most patients do complain of pain
• Radiographically it is a well circumscribed lesion with a rim of
sclerosis in the metaphysis of a long bone and may have bubbly
appearance but in contrast to other cartilaginous lesions,
radiographic evidence of intralesional calcification usually is
absent.

87. Non ossifying fibroma
• Nonossifying fibroma/ metaphyseal fibrous defects/
fibrous cortical defects/ fibroxanthomas are common
developmental abnormalities and are believed to occur
in 35% of children.
• Lesions in metaphyseal region of long bones between
ages 2 to 20 years old.
• Distal femur> Tibia>Fibula
• Appears as a well defined lobulated lesion located
eccentrically in the metaphysis, multilocular, sclerotic
scalloped borders, and erosion of borders are frequent
findings.

88. Fibrous dysplasia
• Developmental anomaly of bone formation that may exist in
monostotic or polystotic form.
• The hallmark is replacement of normal bone and marrow by
fibrous tissue and small, woven spicules of bone.
• Fibrous dysplasia can occur in epiphysis, metaphysis or
diaphysis.
• Fibrous dysplasia is associated with syndromes including
McCune-Albright syndrome(polyostoic fibrous dysplasia,
cutaneous pigmentations and endocrine abnormalities) ,
Mazabraud syndrome(fibrous dysplasia with
intramuscular myxomas)
• The radiographic appearance is characteristic, with lucent
area having granular, ground glass appearance with well
defined sclerotic rim.

89. Brown tumour of hyperparathyroidism
• Primary hyperparathyroidism is usually caused by
adenoma of the parathyroid gland.
• Secondary hyperparathyroidism can occur in
patients with chronic renal failure.
• In early stages, the skeletal change is only limited to
diffuse demineralisation only rarely does the change
become markedly focal and produce a “brown
tumour” which resembles a GCT.
• The diagnosis of hyperparathyroidism should be
established by determining serum calcium,
phosphorous, alkaline phosphatase and parathyroid
hormone levels, rather than histological
examination of focal lesion.

90. THANK YOU