a brief summary of bone tumours

1. BONE
TUMOURS
GENERAL FEATURES,
CLASSIFICATION AND MANAGEMENT

2. Introduction
 It is defined as those conditions of the skeletal system that are neoplastic or could be
mistaken for a neoplastic condition based on radiological and/or pathological
evidence.
 Overview-
 Diverse in morphology and biological potential
 Most bone tumours are benign lesions
 Most lesions are seen in <30 years of age
 Location in the bone gives important diagnostic information
 More common benign lesions typically present as incidental findings(not painful and stable
size)
 Painful lesions and those that grow relatively fast (weeks/months) are likely to be malignant
 A pathological fracture can be the first sign of a tumour.

3. GENERAL CONCEPTS OF TUMOUR
 Growth and behaviour:
Most neoplasms grow progressively in all directions and tend to retain a spherical size.
Certain lesions tend to grow asymmetrically, causing an elongated appearance in bone,
like Ewing’s sarcoma, angiosarcoma
 Pseudocapsule:
It's a capsule made up of compressed tumour cells that surround the tumour
This capsular zone is often involved microscopically with tumour, and the surgical
procedure that violates this capsule is likely to leave residual cancer cells

4. GENERAL CONCEPTS OF TUMOUR
 True capsule:
Surrounds a benign lesion
Composed of compressed normal cells and mature fibrous tissue
 Compartment:
Refers to anatomical structure or space surrounded by a natural barrier, a muscle
compartment is surrounded by fascia
Intracompartmental: bone tumour within the cortex
Extracompartment: when bone tumour destroys the cortex and spreads into the
surrounding soft tissue

5. GENERAL CONCEPTS OF TUMOUR
 Skip metastasis:
High-grade sarcomas can break through the pseudocapsule and metastasise within the
same compartment
Intraosseous-embolisation of tumour cells within the marrow sinusoids
Transarticular-occur via periarticular venous anastomosis

6. CLINICAL PRESENTATION
 PAIN LESS BONY MASS :
The most common differential in the adolescent age group is Exostosis. In Exostosis,
growth of the lesion may parallel normal skeletal growth.
Although solitary exostosis rarely undergoes malignant transformation, a history of
recent growth in a previously dormant bony mass should provoke further investigations
 PAINFUL BONY MASS:
Benign latent or active bone tumours are usually not painful unless there is a fracture,
except for osteoid osteoma, which has a well-defined pain syndrome.
Pain associated with bone tumours is usually malignant.
Aggressive and malignant bone tumours are also known to produce proteinases that
stimulate pain

7. CLINICAL PRESENTATION
 SOFT TISSUE MASS:
Patient can present with soft tissue mass with or without bony lesions.
Time since the mass or rapid increase in size of lump is also important
Benign tumours usually do not have an associated soft tissue mass
Associated soft tissue mass is a feature of malignant and aggressive lesion
Some non neoplastic lesion also present as soft tissue component eg:osteomyelitis
Here the associated mass is usually poorly defined and the fatty layers appear
obliterated
Soft tissue extension in malignant process extends through the broken cortex but the
tissue plane are usually intact

8. CLINICAL PRESENTATION
 SOFT TISSUE MASS:
A bony lesion associated with a soft tissue mass should prompt the question, which
came first: is the soft tissue lesion an extension of a primary bone tumour, or is it a
primary soft tissue tumour invading bone?
Ewing sarcoma exhibits a large soft tissue mass accompanying a small primary bone
malignancy.
Primary soft tissue tumours adjacent to bone usually destroy the neighbouring
periosteum without eliciting a periosteal response.
Neurofibromatosis is associated with one or more soft tissue masses
Maffucci syndrome: multiple enchondroma with soft tissue haemangioma
In primary bone there is a prompt periosteal reaction when they grow into the cortex
and then extend into soft tissue

9. CLINICAL PRESENTATION
 BONE TUMOURS AS INCIDENTAL FINDING:
Patient suffers from either a minor injury or symptoms related to non-neoplastic
musculoskeletal pathology.
Most commonly seen with the knee and shoulder because these two sites are
associated with benign latent lesions
 PATHOLOGICAL FRACTURE:
The cause of the fracture is weakening of the bone through circumferential erosion of
the endosteal cortex.
It can be associated with malignant or aggressive bone tumours or even a benign active
lesion in the paediatric age group # and is mainly associated with UBC, non-ossifying
fibroma, fibrous dysplasia-

10. NUMBER OF LESION:
 Benign lesions tend to involve multiple sites, as in polyostotic fibrous
dysplasia, enchondromatosis, multiple osteocartilaginous exostoses,
hemangioma and fibromatosis
 Primary malignancy such as osteosarcoma, Ewing’s sarcoma, fibrosarcoma,
rarely present as multifocal disease
 Multiple malignant lesions usually indicate metastatic disease

11. SITE OF LESION/AGE OF PATIENT
 AGE: most musculoskeletal tumours occur in a specific age range
• When tumors do occur outside of their typical age group, they may not appear
in the usual locations or may have a different radiographic appearance.
• In simple bone cysts (so-called unicameral bone cysts), Before skeletal
maturity, they usually arise in the proximal humerus or proximal femur.
• After skeletal maturity, however, they may be found in the calcaneus,
scapula, or pelvis, among other places; with aging, they may look somewhat
unconventional on radiography.

12. AGE OF PATIENT

13. SITE OF LESION IN VERTICAL PLANE

14. SITE OF
LESION IN
TRANSVERSE
PLANE

15. SITE OF LESION
 In transverse plane:
1. Central: Enchondroma, simple bone cyst,
2. Eccentric: GCT, osteosarcoma, chondromyxoid fibroma
3. Cortical: non-ossifying fibroma, osteoid osteoma
4. Parosteal: parosteal osteosarcoma, osteochondroma
 In longitudinal plane:
1. Diaphyseal: Ewing’s, osteoid osteoma, Mets, Admantinoma, Fibrous dysplasia
2. Ephyseal: Chondroblastoma, GCT, ganglion of bone
3. Metaphyseal: Osteosarcoma, osteochondroma, aneurysmal bone cyst,
Enchondroma

16. RADIOGRAPHS
 Borders of the lesion:
Margin with sharp demarcation by sclerosis between the peripheral aspect of the
tumour and the adjacent host bone.
Margin sharp demarcation without sclerosis around the periphery of the lesion.
Margins which are ill-defined
 Slow-growing lesions are marked by sharply outlined sclerotic borders, and
this narrow zone of transition usually indicates that the tumour is benign
 Indistinct borders are typical of malignant or aggressive lesions. Metastasis
also lacks sclerotic borders, as does the giant cell tumour.
 If an intramedullary bone tumour is non-permeative and static or slow
growing, the host bone has an opportunity to respond to its presence by
producing a sclerotic rim of compact bone

17. RADIOGRAPHS
 On the other hand, the absence of a
sclerotic rim indicates that the tumour is
growing faster than the rate at which the
host bone can respond
 More well-defined margin, slower the
biological activity and likely to be benign
 Less well-defined margin, higher the
biological activity and
likely to be malignant

18. PATTERNS OF BONE DESTRUCTION
 Geographical destruction:
It is characterised by a uniformly destroyed area, usually with sharply defined borders.
The key X-ray feature is the visible zone of transition between the bone that has
undergone destruction and the completely intact bone.
It implies the growth rate of the tumour is slow
Eg: giant cell tumour

19. PATTERNS OF BONE DESTRUCTION
 MOTH EATEN DESTRUCTION:
 it is characterised by multiple 2-5 mm holes that have a tendency to
coalesce.
 The holes are pockets of cortical destruction, and the zone of transition of
each hole is ill-defined.
 It represents moderately aggressive tumours.
 Benign: OM
 Malignant: Metastatic disease, Myeloma

20. PATTERNS OF BONE DESTRUCTION
 PERMEATIVE DESTRUCTION:
 Characterised by multiple tiny holes which are less than 1 mm dimeter
 X-ray shows ill-defined, segmental loss of bone density.
 The small holes are the haversian system enlarged by enzymatic and/or
osteoclastic activity
 Benign: OM
 Malignant: Ewing’s sarcoma, Osteosarcoma

21. PATTERNS OF BONE DESTRUCTION

22. RESPONSE OF BONE TO TUMOUR
RIM OF HOST BONE SCLEROSIS:
 A complete rim of host bone sclerosis is one of the most
valuable radiological signs.
 If a lesion is not growing or the growth rate is extremely
slow, the bone around the periphery of the lesion usually
responds by forming a surrounding wall.
 This formation is a natural host response of the bone in an
attempt to contain the lesion.
 The stimulated bone around the periphery of the lesion
appears white on radiograph and can be referred to as
reactive host bone sclerosis

23. RESPONSE OF BONE TO TUMOUR
EXPANDED BONES:
 This occurs when a tumour or a tumour process grows
until the cortex is eroded by the osteoclastic
destruction stimulated by tumours.
 If growth is slow enough, then the periosteum lays
down a reactive new bone which keeps pace with the
growth of the tumour
 The smooth periosteal new bone actually becomes
new cortex and blends into the uninvolved cortex
above and below the lesion. This appears as an
expanded or balloon-like appearance
 80%- benign
 20%- malignant

24. RESPONSE OF BONE TO TUMOUR
PERIOSTEAL REACTION:
 It is a formation of new bone in response to injury or other stimuli to the
periosteum surrounding the bone.
 Any widening or irregularity of bone contour represents periosteal activity
 Can be INTERUPTED or UNINTERUPTED

26. RESPONSE OF
BONE TO TUMOUR
Uninterrupted periosteal reaction:
 represents a long-standing, usually
indolent, benign process
SOLID PERIOSTEAL REACTION:
 single solid layer or multiple closely
apposed and fused layers of new bone
attached to the outer surface of the cortex
 The resulting pattern is referred to as
cortical thickening
 The expansion of bone is a result of a
relatively slow bone-destroying process that
has evoked the removal of bone from the
endosteal surface of the cortex at a rate
balanced production of new bone on the
periosteal surface

27. RESPONSE OF BONE TO
TUMOUR
INTERUPTED:
 Commonly seen in malignant and some metastatic
lesions
 Eg: sun burst appearance, onion peel appearance,
codman’s triangle
CODMAN'S TRIANGLE:
 It is a triangular cuff of reactive periosteal bone at
the edges of a lesion caused by an expanding
mass. The apex of the triangle represents the most
peripheral aspect of the stimulated periosteum.
Base represents the border of the tumour or
tumourous lesion with splayed periosteum.
 Eg: osteosarcoma, GCT rarely
 Rapidly growing benign process like ABC OM

29. RESPONSE OF BONE TO TUMOUR
ONION SKINNING LESION:
 An episode of intramedullary tumour expansion with
necrosis or infarction, which leads to intense oedema
 This oedema penetrates the haversian system, lifting the
fibrous periosteum in convex manner. When this oedema
abates, the smooth raised periosteum is irritated or
stimulated to produce a sheath of bone.
 This cycle is repeated one or more times.
 Most commonly associated with
1. Ewing’s sarcoma
2. OM
3. Osteosarcoma of the shaft.
 In Ewing’s Sarcoma, layers tend to be thinner or finer
when compared to the latter two.

30. RESPONSE OF BONE TO TUMOUR
 PERPENDICULAR
PERIOSTEAL LESION:
[sunburst, spiculated,
wavy]:
 These lines probably result
from rapid continuous
lifting and periosteal
stretching.
 The periosteum is attached
to the cortex by
perpendicularly placed
Sharpey fibres along which
the irritated periosteum is
probably stimulated
to lay down bone

31. TUMOUR MATRIX
 Tumour new bone is the matrix of intercellular substance produced by certain
tumour cells that can calcify or ossify.
 Radiodense tumour matrix is of either osteoid (osteogenic tumours) or
chondroid (chondrogenic tumours) origin.
 A radiographic study of the matrix frequently can yield sufficient findings to
differentiate between chondroblastic and osteoblastic processes and may help
in distinguishing between lesions similar in appearance.

32. TUMOUR MATRIX
 Tumour cartilaginous matrix is more amorphous,typically
with calcifications.
 stippled or punctate,
 ring and arc
 flocculent / irregularly shap
 Composition of tumour tissue—
chondroid matrix. Both
enchondroma (A) and
chondrosarcoma (B) display a
typical chondroid

33. TUMOUR
MATRIX
 T
umour osteoid - presence of fluffy,
cotton-like densities within the
medullary cavity
• solid (sharp-edged)
• cloud
• ivory-like
 the presence of fluffy, cotton-like
densities within the medullary cavity
such in this case of osteosarcoma of
the distal femur (A), case of
osteosarcoma of the sacrum (B), or by
the presence of a solid sclerotic mass,
like in this case of parosteal
osteosarcoma of the femur (C).

35. Grading and staging of cancer
 These are two systems that determine the prognosis and choice of treatment.
 1. Grading is defined as the macroscopic and microscopic degree of
differentiation of a tumour.
 2. Staging: is defined as the extent of spread of the tumour within the
patient. Done by clinical examination, by investigations and by
pathological examination.

36. Broders grading
 Grade 1:Well differentiated (less than 25% anaplastic cells)
 Grade II : Moderately differentiated (25-50% anaplastic cells)
 Grade III : Moderately differentiated (50-75% anaplastic cells)
 Grade IV : Poorly differentiated or anaplastic (More than 75% anaplastic cells)

37. ENNEKING STAGING SYSTEM
 reliable, reproducible, and has prognostic importance for
musculoskeletal sarcomas, especially for those originating
in the axial skeleton.
 Enneking staging system applies only to mesenchymal
malignancies.

38. Enneking Staging System for benign
musculoskeletal tumors
 This classification is based on radiographic
characteristics of the tumour-host margin.
 It consists of three categories:
stage 1- latent,
stage 2 - active, and
stage 3 -aggressive.

39. STAGE 1 – LATENT :
 Intracapsular
 Usually asymptomatic
 Frequently, an accidental finding
 Low biologic activity
Radiography:
 Well-defined margins with a thick rim of reactive bone
 No cortical destruction or expansion
 Usually do not require treatment as they do not compromise the
strength of the bone
 Usually resolves spontaneously
Eg: non ossifying fibromma

40. STAGE 2 – ACTIVE
 Also intracapsular
 But actively growing
 Cause symptoms or lead to a pathological fracture
Radiography:
 Well-defined margins
 Expansion and thinning of the cortex present
 Have a thin rim of reactive bone
 Limited bone destruction
 Growth limited by natural barriers
 Negligible recurrence after marginal resection
 Treatment usually involves extended curettage
 EX: ANEURYSMAL BONE CYST

41. STAGE 3 – AGGRESSIVE :
 Extracapsular
 Aggressive bone destruction or soft tissue extension
Radiography:
 Ill-defined margins/ borders
 Growth not limited by natural barriers
 5% may have metastasis
 High recurrence after intracapsular or marginal resection
 Wide resection preferred
 EG: GIANT CELL TUMOUR

42. ENNEKING SURGICAL STAGING SYSTEM
FOR MALIGNANT MESENCHYMAL
TUMORS
 The surgical grade (G1, G2)
 Site (T1, T2)
 Presence or absence of metastasis (M0, M1)
 Stage III - any tumour with distant metastasis.
 Stage II - high grade
 Stage I - low grade
 Stage I and II are further subdivided into two subcategories (A, B) based
on the local extent of the tumour.
 The stage of the tumour dictates the extent of surgical resection and
margin

43. ENNEKING
SURGICAL
STAGING
SYSTEM FOR
MALIGNANT
MESENCHYMAL
TUMORS
GRADES:
low (G1) or high (G2) grade.
Low grade – G1
 Low risk for distant spread (< 25%).
 Low mitotic rates
 Low nuclear to cytoplasmic ratio
 Limited pleomorphism.
High Grade – G2
 Higher incidence of metastasis
 Mitotic figures are seen on histology
 Prominent nucleoli

44. LOCAL EXTENT/ SITE:
 Intracompartmental (T1) / extracompartmental (T2)
 Anatomical compartments have natural barriers, e. g. cortical bone, articular cartilage,
fascial septae, muscle origins, joint capsule, etc.
 The adequacy of the surgical margin is determined by this barrier between the plane of
resection and the tumour.
 determines the approach for the surgical procedure and feasibility for the desired surgical
margins.
 A localised tumour can be removed by a smaller margin
 High-grade lesions may require the use of adjuvant therapies to eradicate tumour cells that
would remain after surgical resection.

45. METASTASIS:
 The last major determinant in the surgical staging
system is whether or not the patient has
metastases to a distant site or the regional lymph
nodes[ stage III = metastatic disease].
 The presence of metastatic disease denotes a
poor prognosis.

49. Limitations of the Enneking surgical
staging system
 based on the natural evolution of mesenchymal tumours
 thus does not apply to tumours originating in either the
marrow or reticuloendothelial system.
 Including lymphomas,
multiple myeloma,
plasmacytoma,
Ewing’s sarcoma and other round cell
neoplasms,
metastatic carcinomas

50. TNM STAGING OF BONE TUMOURS
Primary tumour (T):
 TX Primary tumour cannot be assessed
 T0 No evidence of primary tumour
 T1 Tumour ≤8 cm in greatest dimension
 T2 Tumour>8 cm in greatest dimension
 T3 Discontinuous tumours in the
primary bone site
Regional lymph node (N)
 NX Regional lymph node cannot be
assessed
 N0 No regional lymph node metastasis
 N1 Regional lymph nodes metastasis
Definition of distant metastasis (M)
• M0 No distant metastasis
• M1 Distant metastasis
 M1a Lung
 M1b Bone or other distant sites
 Histologic Grade (G)
• GX Grade cannot be assessed
• G1 Well differentiated, low grade
• G2 Moderately differentiated, high grade
• G3 Poorly differentiated, high grade

51. AJCC PROGNOSTIC STAGING OF
BONE SARCOMA

53. WHO Classification of Bone Tumours
 WHO has recommended a widely accepted classification of primary bone
tumours based on histogenesis and histological criteria
1. Bone-forming tumours
2. Cartilage-forming tumours
3. Giant cell tumour
4. Marrow tumours
5. Vascular tumours
6. Connective tissue tumours
7. Other tumours
8. Tumour-like lesions

55. WHO Classification of Bone Tumours
BONE FORMING TUMOURS.
 BENIGN:
 Osteoma
 Osteoid Osteoma
 Osteo Blastoma
 MALIGNANT
 Osteo Sarcoma.
 Juxta cortical osteosarcoma
 Periosteal osteosacrcoma

56. WHO Classification of Bone Tumours
CARTILAGE FORMING TUMORS
 A. Benign
 Chondroma
 Osteochondroma
 Chondromyxoid fibroma
 Chondroblastoma
 B. Malignant
 Chondrosarcoma

57. WHO Classification of Bone Tumours
GAINT CELL TUMOR
 Classical benign type
 Malignant giant cell tumour
 Gaint Cell Tumor in paget disease of facial bones
 GCT in long bones occurring in non epiphyseal region
 Variants of Giant cell tumour
MARROW TUMORS
 EWINGS SARCOMA
 RETICULO SARCOMA OF BONE
 Lymphosarcoma of bone Myeloma

58. WHO Classification of Bone Tumours
VASCULAR TUMOR
 Benign
 Haemangioma
 Lymphangioma
 Glomus tumour
 MALIGNANT
 Angiosarcoma

59. WHO Classification of Bone Tumours
CONNECTIVE TISSUE TUMOURS
 Benign
 Desmoplastic fibroma
 Lipoma
 Malignant
 Fibrosarcoma
 Liposarcoma

60. WHO Classification of Bone Tumours
TUMOR-LIKE LESIONS
 Solitary bone cyst
 Aneurysmal bone cyst
 Ganglion
 Nonossifying fibroma
 Fibrous dysplasia
 Eosinophilic granuloma
 Myositis ossificans
 Brown tumour of hyperparathyroidism

61. WHO Classification of Bone Tumours
Other tumours
 Chondroma
 Admantinoma
 Naurilemmoma
 Neurofibroma

62. CLASSIFICATION depending upon site of
lesion in long bones
 Epiphyseal
Osteoclastoma. Chondroblastoma
 Metaphyseal
Osteoid Osteoma, Osteoblastomas, Enchondromas, Osteochondromas (exostosis), Bony
cysts, Osteogenic sarcomas
 Diaphyseal
Ewing's sarcomas, Multiple myelomas

63. Classification based on origin
 Primary bone tumors:
Are the tumours arising denevo from the bone. Divided into Osseous tumours and
Nonosseous tumours, and described previously
 Metastatic bone tumours:
includes metastasis from breast, thyroid, and lung. liver, prostate, urinary bladder and
uterine cervix in the bone.

64. Classification based on origin
 Tumour-like lesions include several non-neoplastic conditions that resemble
true neoplasms and have to be distinguished from tumours clinically,
radiologically and morphologically. These includes the following:
Solitary bony cyst (simple/unicameral bony cyst)
Aneurysmal bony cyst
Juxta-articular bony cysts
Eosinophillic granuloma
Fibrous dysplasia
Non-ossifying fibroma (Metaphyseal fibrous defect)
Brown’s tumour of hyperparathyroidism
Histiocytosis - X (Langerhan's cell histiocytosis)i)
Ganglion cyst of bone
Myositis ossificans

65. BENIGN VS MALIGNANT TUMORS

66. GENERAL MANAGEMENT
 Usually an incidental finding
 But may present as
Painless lump
Painful mass
Rapidly growing swelling
Or a sudden onset of pain in a painless mass
 Plain radiograph is the first investigation which reveals the bone tumour

67. GENERAL MANAGEMENT
 GENERAL PHYSICAL EXAMINATION:
Anaemia: myeloma
Café au lait skin patches: These are large brown skin patches with have smooth outer
border [coast of California) and are seen with patients with neurofibromatosis and
Jaffe Campanacci syndrome
Palpable lymph node: lymphatic metastasis is rare with musculoskeletal tumours
Dilated or engorged veins over the mass indicate underlying malignancy
 Systemic examination:
RS: chest examination to rule out secondaries in the lung

68. GENERAL MANAGEMENT
 Laboratory data:
 CBC: anaemia may be seen due to replacement of bone marrow by neoplastic cells
rule out infection and leukaemia
 ESR: Raised in Metastasis, Ewing's sarcoma, Lymphoma, Leukaemia
 Hypercalcaemia: indicates Metastasis, Myeloma, Hyperparathyroidism
 Increased alkaline phosphatase: ALP is raised in any osteoblastic activity
 Blastic metastasis, like prostate and breast
 Active Paget’s disease
 Hyperparathyroidism
 Growth spurt
 Eosinophilia: eosinophilic granuloma

69. Role of CT scan in Bone Tumours
 To determine intramedullary and extramedullary extension
 To know the relation between tumour and vital structure
 Evaluate the integrity of the cortex
 To differentiate solid and cystic lesions.
 Localise nidus in osteoid osteoma
 To detect a thin rim of reactive bone around an aneurysmal bone cyst
 Evaluate endosteal cortical erosion in chondrosarcoma
 To distinguish neoplastic mass and inflammatory mass. Neoplastic masses displace soft
tissue fat planes where whereas they are obliterated in inflammatory conditions.
 One entire length of the lesion, ie, one normal scan above and below the lesion,
should be scanned

70. Role of CT scan in Bone Tumours
 Overestimation of size may occur if oedema is present surrounding
the lesion, and underestimation of size may occur if paucity of
adipose tissue is present
 Contrast CT is better compared to plain CT, except in pulmonary
evaluation for metastasis, where plain is preferred
 CT is particularly helpful in tumours of the axial skeleton
 CT should be done before biopsy because post-biopsy haematoma may
be confused for tumour

71. Role of CT scan in Bone Tumours
 Disadvantages:
It doesn't differentiate benign from malignant
It involves radiation
It produces images in one plane
 To detect joint invasion CT and MRI are equally
accurate.

72. MRI
 It does not involve ionising radiation
 Most accurate method of determining the limits of disease
both within and outside the bone
 Directly visualizes the bone marrow content.
 Demonstrates intramedullary extension of neoplasm
 Identifies skip lesion
 It is capable of producing images in any desired plane

73. MRI
Features of malignancy on MRI:
 Mass with irregular border
 Non-homogeneous signal intensity with extra
compartmental extension“
 Peritumoural edematous reaction
 In case of soft tissue sarcoma, any mass situated deep to
the fascia and measuring more than 5 cm in its greatest
diameter is considered likely to be a sarcoma

74. CT VS MRI
Feature CT MRI
Bone cortex Excellent Good, but less than CT
Marrow involvement Limited Excellent
Soft tissue extension Moderate Excellent
Matrix mineralization
Excellent (detects
calcification/ossification)
Poor (signal void only)
Periosteal reaction Excellent Moderate
Vascular/Neuro involvement Poor Excellent
Skip lesions Poor Excellent
Radiation Present Absent
Availability/Cost Widely available, cheaper Less available, expensive

75. CT VS MRI
 CT = best for detecting
bone destruction,
calcification, and
surgical planning.
 MRI = best for tumour
staging, marrow and
soft tissue assessment,
and surgical excision
planning.

76. BONE SCAN
 The radionuclide bone
scan is an indicator of
mineral turnover
because there is
usually enhanced
deposition of bone-
seeking radio
pharmaceutical agents
in areas undergoing
change and repair.
 Bone scan is useful in
localising tumours and
tumour-like
lesions in the skeletal.

77. BONE SCAN
 Whenever there is altered metabolism in remodelling bone, increased
vascularity or increased mineralisation, the isotope uptake is enhanced
mainly in the reactive zone surrounding the lesion, esp. in conditions like
fibrous dysplasia, Langerhans cell histiocytosis and metastatic cancer in which
more than one lesion is encountered.
 Technitium 99 methylene diphosphate is the compound used along with a
gamma camera, wherein the compound is injected intravenously and images
are taken 3-4 hours later.

78. BONE SCAN
 Bone scan is mainly used:
 To detect skeletal metastasis from a primary elsewhere in the body
 To detect multiple lesions, like multiple osteochondromas, enchondromas
 In localising small lesions such as osteoid osteoma
 Although a bone scan is highly sensitive, its specificity is low.
 In most instances, it cannot distinguish benign from malignant lesions because
increased blood flow, with increased isotope deposition with increased osteoblastic
activity, takes place in both benign and malignant lesions

79. ANGIOGRAPHY
 It has a limited role
 It is used to demonstrate the vascular supply of
the tumour
 To localise the vessels suitable for preoperative
intra-arterial chemotherapy
 To demonstrate the area suitable for open biopsy,
as most vascular parts contain the most aggressive
tumours
 In highly aggressive tumours pre preoperative
angiography is used to suppress selective blood
supply by means of arterial embolisation
 Transcatheter embolisation is employed as a
definitive treatment in some benign vascular
tumour like haemangioma

80. POSITERON EMISSION
TOMOGRAPHY
 It is useful in staging, planning of
biopsy, and evaluating the response to
chemotherapy
 PET differs from other single-photon
radio nuclide scans in its ability to
correct tissue attenuation signal loss
and its relatively uniform spatial
resolution
 It observes the metabolism of
musculoskeletal lesions based on
observations og high glycolysis rates of
malignant tissue
 Whole body F-labelled 2- 2-fluoro 2-
fluoro-2-deoxy glucose PET scanning is
valuable in identifying primary
recurrent and metastatic cartilage
tumours

81. POSITERON EMISSION
TOMOGRAPHY
 The process produces biological
images based on the detection of
gamma rays that are emitted by
radioactive substances such as
FDG
 It detects primary and metastatic
tumours
 It is more sensitive than CT and
MRI
 But it has low specificity because
FDG may also accumulate in
benign aggressive, and
inflammatory lesions

82. BIOPSY
 Biopsy is a procedure to remove a piece of tissue in a sample of cells from the desired
area for microscopic amd cytological analysis
 It is the single most important step in staging, to determine histogical diagnosis and hence
plan the treatment
 Types: open or closed
 CLOSED:
 FINE NEEDLE ASPIRATION BIOPSY [FNAB]
 CORE NEEDLE BIOPSY
 TRUCUT BIOPSY
 In circumstances, for bone tumours to be accessible for FNAB and coree biopsy, soft tissue
extension or sufficient cortical destruction or both must be present
 The tumours that are predominantly sclerotic are not adequately sampled especially with FNAB

83. BIOPSY
 Open: excisional or incisional
 WEDGE BIOPSY: It’s the type of excisional biopsy wherein the lesion
identified at the time of surgical procedure is removed with a wedge of
normal surrounding tissue
 TIMING: If a biopsy sample is taken before a CT scan of a lesion, haemorrhage
induced by the biopsy can create the illusion of a malignant soft tissue mass
 Always biopsy should be done after clinical, laboratory and imaging studies
are complete, so that it helps in proper placement of biopsy incision and
avoids artefacts on imaging studies

84. BIOPSY
 Advantages of open biopsy:
More tissue is obtained for histologic and ultramicroscopic evaluation
Sampling errors are reduced. Chances of crushing of tissues are reduced.
Tumour host bone interface, which is important to differentiate enchondroma from
chondrosarcoma, osteoblastoma from osteosarcoma, can be obtained
Both cytological and tumour patterns are visible
 BIOPSY SITE:
Be small as feasible
Be placed longitudinally
Avoid major neurovascular structures

85. Definitive surgery after Biposy
 During biopsy, take a frozen section; if it confirms radiological diagnosis,
definitive procedure should be done immediately following biopsy.
 If diagnosis is doubtful- delay the definitive procedure till a firm diagnosis is
made

86. Indication of Primary Resection Without
Biopsy
 A subcutaneous lesion <5 cm may be marginally resected
primarily
 Benign bone lesions like osteoid osteoma,
osteochondroma, etc, which have characteristic X-ray
findings, can be resected
 Painful lesion in an expandable bone, such as the proximal
fibula, distal ulna, can be primarily dissected

87. 0NCO-SURGERY
 4 types of Excision
1. Intralesional or debulking or Currettage
of tumour
2. Marginal excision
3. Wide excision
4. Radical excision

88. Intralesional or debulking or Currettage of tumour
 Here, the dissection is within the tumour. It leaves behind
gross residual tumour tissue.
 It is done in symptomatic benign lesions.
 It’s contraindicated in malignant tumours unless it is
coupled with the use of an agent that destroys each and
every cell
 Eg: cryo surgery, wherein the tumour is frozen
with liquid nitrogen

89. MARGINAL EXCISION
 Here, the plane of dissection passes through the pseudo
capsule. This marginal margin is achieved when the
closest plane passes through the pseudo capsule
 This is adequate to treat most benign tumours and low-
grade malignant tumours
 It is contraindicated in high-grade malignancy because the
pseudo capsule often contains microscopic foci known as
satellite lesions, where marginal resection leaves behind
those satellites, leading to recurrence

90. WIDE EXCISION
 Here the plane of dissection passes in normal
tissue so that the entire tumour remains
completely surrounded by cuff of normal tissue.
Frequently combined with pre or post operative
adjuvant chemo or radiotherapy

91. RADICAL EXCISION
 It is a procedure in
which the tumour,
pseudo capsule,
reactive zone and
entire bone, as
well as possibly the
contiguous joint
apposing bone end
and muscle tissue,
are removed as a
single unit.

92. CURETTAGE
 Compared to local resection, it is associated with higher local recurrence but
often allows for a better functional result in many benign tumours
SURFACE CURETTAGE:
 It is done by making a large cortical window over the lesion, measuring about
the size of the lesion, to avoid leaving residual tumour
 The bulk of the tumour is then scooped out with large curettes
 Using a power burr cavity is then enlarged by 1-2 cm in each direction
 Finally, the cavity and the wound should be copiously irrigated to remove any
debris and tumour cells

93. CURETTAGE
EXTENDED CURETTAGE:
 It includes the use of adjuvants like liquid N2, phenol, PMMA, or thermal
cautery to extend the destruction of tumour cells
 It reduces the recurrence rate.
 Adjuvants:
 LIQUID NITROGEN is applied by direct pour technique and may be
associated with greater complications2.
 Phenol has relatively poor penetration into bone [<1 mm]
 3. The depth of necrosis in cancellous bone treated with argon beam
coagulation is approximately 4 mm.
 4. PMMA bone cement acts as an adjuvant through its heat
polymerisation. Can also be used as a filling agent in post-
curettage cavity

94. THANK YOU

97. Simple Bone Cyst
 Also known as unicameral
bone cyst
 Age: 1st to 2nd decade
 Site: Proximal humerus >
proximal femur > proximal
tibia
 When tumor lies nearer to
physis, it is called active
tumor and it migrates
towards diaphysis it
becomes inactive tumor.

98. Simple Bone Cyst
Description of a tumor
radiographs:
 Tumor location:
Metaphyseal/
diaphyseal, centrally
placed
 Destruction pattern: Lytic
 Margin of tumor: Well
defined
 Corticomedullary
delineation: Lost
 Status of cortex: Thinned
out

99. Simple Bone Cyst
 Matrix: Homogeneous
 Zone of transition: Narrow
 Periosteal reaction: Absent (present only with pathological fracture)
 Soft tissue extension: Absent
 Note: Fallen fragment sign in X-ray is a pathognomonic feature for a simple bone cyst
with fracture.
 presence of a gas bubble in most nondependent areas of a simple bone cyst, called the
rising bubble sign

100. GROSS
 If an intact cyst is removed
 Straw or clear fluid-filled large
intramedullary cavity
 Usually unilocular but may be
multilocular
 Thin and smooth cyst membrane
 In curettage specimens
 Multiple thin greyish or reddish
membranes admixed with blood
clots and bony fragments

101. Treatment
1) If small and low risk of fracture
• Some cases resolve spontaneously with age.
• Intralesional Steroid
An injection of Methylprednisolone Acetate into the lesion in several intervals
for a time span of 6-12 months.
Complications are infection, fracture or recurrence.
2) If the risk of fracture or a large lesion
• Curettage
• Bone grafting
It is performed after curettage. The empty cavity is transplanted with donor bone tissue, bone
chips or artificial material.

102. Aneurysmal bone cyst
 A vasocystic tumor formed following Arteriovenous malformation in
metaphysis (most accepted theory)
 Age: 1st to 2nd decade
 Site: Proximal humerus > proximal femur >proximal tibia > spinous process
 ABC of spinous process closely resembles osteoblastoma.

103.  Tumor location:
Metaphyseal/diaphyseal, eccentric
 Destruction pattern: Lytic,
expansile.
 Margin of tumor: Well defined
 Corticomedullary delineation: Lost
 Status of cortex: Thinned out or egg
shell
 Matrix: Homogeneous
 Zone of transition: Narrow
 Periosteal reaction: Present (solid-
soap bubble septation)
 Soft tissue extension: Absent
 Finger in the balloon sign possible
 Does not extend to the joint (unlike
GCT)

104. CT scan:
Well-delineated lytic lesion, usually
with a thin rim of reactive bone
Fluid-fluid levels are occasionally
visible
MRI:
Multiloculated cyst with
characteristic fluid-fluid levels
Isotope scan:
Peripheral uptake with central
photopenia imparts a doughnut-like
appearances

105. Gross
description
Spongy, multiloculated, hemorrhagic
lesion
Variable size
Irregular, sharply demarcated borders
with thin shell of reactive bone
Variable amount of solid component

106. Treatment
 Surgical treatment: Extended curettage and grafting with a bone graft substitute .
 Expendable bones : Marginal resection.
 Spine or pelvis:
Treated with preoperative embolization to minimize surgical blood loss.
Arterial embolization used as definitive treatment of aneurysmal bone cysts in locations
where curettage extremely difficult.
 The recurrence rate after curettage approximately 11 to 20%.
• Recurrence correlated with
age younger than 15 years,
centrally located cysts,
incomplete removal of the cystic cavity contents.
• Recurrent cysts treated with the same approach as the primary lesion.

107. Treatment
• Recurrence correlated with
age younger than 15 years,
centrally located cysts,
incomplete removal of the cystic cavity contents.
• Recurrent cysts are treated with the same approach as
the primary lesion.
Radiotherapy:
• Low-dose irradiation is an effective method of treatment.
• associated with rapid ossification
.• Not used routinely because of the potential for malignant transformation.

108. Osteochondroma
 WHO defined it as a cartilage capper bony projection on the
side of the bone.
 Also known as Extosis.
 It is the most common benign tumour of bone
 Age: 2nd decade
 M>F
 Not inherited
 Site: Distal femur > proximal tibia > proximal humerus

109. Osteochondroma
 Tumour location: Metaphyseal
 Size: 1-15 cms
 Direction of growth: Away from joint
 Stalk: Pedunculated or sessile
 Margin of tumour: Well defined
 Corticomedullary delineation: Intact
 Cortical part of tumor: It is continuous with cortex of parent bone
 Medullary cavity of tumor: It is continuous with medullary cavity of
parent bone

110. Osteochondroma
 Clinical Features:
 asymptomatic lesion
 Lumps and bumps
 Pain: can be due to
Mechanical irritation – due to pedunculated osteochondromas
Nerve compression - due to pedunculated osteochondromas
Fracture through the stalk- causes immediate and sharp pain
Malignant transformation- renewed growth of the lesion in
middle to late adulthood, coupled with pain

111. Osteochondroma
Associated with pseudo-aneurysm- during adult life cartilage
cap is partially or completely destroyed; the tip of protrubence is
sharp or has a beveled edge that approximates an artery and has
potential to erode the artery
Most commonly involved is popliteal artery
Can be associated with bursitis- known as exostosis bursata
Osteomyelitis rarely
Juxta-articular lesions may cause limitation of joint movements
Growth disturbances of an extremity

112. Osteochondroma Radiological sign of malignant
transformation in exostosis:
chondrosarcoma.
 Stippled calcification in
ŠŠ
cartilage
cap
 Margin of tumour becomes ill
ŠŠ
defined
 Soft tissue extension
 Cartilaginous cap size more
ŠŠ
than 2 cm in CT or MRI (normally
the thickness of cartilage cap is
more in children,i.e. up to 2
cm, than adults, i.e. in a few
millimetres.

113. Osteochondroma
GROSS FEATURES:
 Grey white tumour
 Broad or narrow base
 Mushroom shaped
 Section shows
cortical bone and
bone marrow
enclosed within
cartilagenous cap

114. Osteochondroma
HISTOPATHOLOGY:
 Hamartomatous
lesion with outer
mature cartilage
resembling
epiphyseal cartilage
 Inner mature
lamellar bone and
bone marrow

115. Osteochondroma
 Staging
 Osteochondromas can be staged under Musculoskeletal Tumour
Society(MSTS) grading
 Stage I- inactive or latent lesion
 Stage II- actively growing lesion
 Stage III- actively growing lesions that are locally destructive
 Most osteochondromas are stage I or stage II

116. Osteochondroma
 Differential diagnosis
 Juxta cortical myositis ossificans
The apparent tumour doesn’t blend with the host bone
 Periosteal chondroma/ Juxtacortical chondromas
Usually have a scalloped cortical defect with a sclerotic margin
 Chondrosarcoma arising in an osteochondroma
In skeletally mature individuals, enlargement of a solitary
osteochondroma, particularly one that is associated with progressive
discomfort, must make us suspicious of the possibility of malignant
transformation into a chondrosarcoma

117. Treatment
 * No treatment necessary for asymptomatic costeochondromas(Observation)
 If the lesion is causing pain or neurologic symptoms due to compression, it
should be resected at the base, and to should be done after skeletal maturity
 None of the cartilage cap or perichondrium should be left in the resection bed
or recurrence can occur.
 As long as the entire cartilage cap is removed, there should be no recurrence.
 Patients with many large osteochondromas should have regular radiographic
screening exams for the early detection of malignant transformation.

118. Ewing’s Sarcoma
• A malignant tumour of neuroectodermal
origin of bone marrow, in the diaphysis
with presence of chromosomal
translocation
• 95% patients have t(11.22)(q24;q12) or
t(21;22)(22;q12) translocations
• It is seen in 5% of all bone tumours, 6% of
all primary malignant bone tumours

119. Ewing’s Sarcoma
 AGE:
5 and 25 years
The peak incidence is during second decade of life
Although 20-30% cases are diagnosed in first decade
 SEX:
Males:females-1.3-1.5:1
 Skeletal distribution:
Any bone can be affected, but it demonstrates a predilection for trunk and long
bones(about 55%)
In the trunk , pelvis predominates, followed by scapula, vertebral column, ribs and
clavicle

120. Ewing’s Sarcoma
 Common Sites:
Most common is femur, followed by humerus, tibia and bones of forearm
 Metastases :
Strong potential to metastasize
Metastasis to lung and other bones
More than 10% of the patients presents with multiple bone metastases at initial
diagnosis
 Size :
Lesion ranges from 2 to 30 cms in maximal dimension
Usually, less than one-half of the bone length is macroscopically involved

121. Ewing’s Sarcoma
 Clinical presentation:
1. Local pain is the first symptom in approx. 50% of the patients,
although it is intermittent and mild at first, tends to increase
rapidly in severity over time, being worse at night
2. Swelling is commonly present ; rapidly growing and painful
3. Swelling is tense, elastic, hard rapidly increasing and
accompanied by heat
4. There are periods of remission with decreased size of tumour
and exacerbation with increased size of tumour over a period
of months to few years

122. Ewing’s Sarcoma
 Clinical presentation:
1. 5% cases presents with pathological fractures
2. Flu like symptoms such as malaise ,weakness and tiredness
3. Death usually occurs due to metastatic involvement of lungs
 Investigations
Hb reduced
Increased ESR, CRP and TC
Leukocytosis
Needle aspiration of Ewing’s sarcoma may grossly resemble pus

123. Description of a tumor radiographs:
Tumor location: Metaphyseal/diaphyseal
Destruction pattern: Permeative
Margin of tumor: Ill defined
Corticomedullary delineation: Lost
Status of cortex: Breached
Matrix: Heterogeneous
Zone of transition: Wide
Periosteal reaction: Present (continuous
lamellated periosteal reaction or onion peel
appearance, spiculated type— sun-burst
appearance and hair on end appearance)
 The Codman triangle is also present sometimes
Soft tissue extension: Present (massive soft
tissue)

124. Grey white, fleshy with extensive
involvement of medulla and cortex
with periosteal elevation
Soft friable necrotic area resemble
pus
Specimens are usually excised
after therapy, and show fibrosis,
hemorrhage and necrosis

125. MICROSCOPY:
Sheets of monomorphic small round, blue cells with
pale and indistinct cytoplasmic borders and small
hyperchromatic nuclei
pseudoRossette formation is characteristically seen
Tumours containing round blue cell( Mneumonic -
PEARL DOMS)
Primitive neuroectodermal tumour
Ewing sarcoma
Acute leukemia
Rhadbomyosarcoma
Lymphoma
Desmoplastic round cell tumour
Osteosarcoma
Mesenchymal chondrosarcoma
Small cell mesothelioma

126. Ewing’s Sarcoma
 Staging for Ewing’s Sarcoma(ENNEKING’S)
EW I – Solitary intraosseous (20%)
EW II- Solitary with extraosseous
extension(60%)
EW III- Multi-centric skeletal(10%)
EW IV – Distatnt mets

127. Treatment
 Highly radiosensitive
 Recurrence common
 Combination of local radiotherapy with systemic
chemotherapy - bring down recurrence.
 Surgery conservative, limb saving.

128. Treatment
 Radiotherapy:
Ewing's sarcoma is a highly radio sensitive and
radiocurabletumor
Main stay of local treatment
Preferred - surgically inaccessible tumours.
Pre or post surgery.
Local failures are common when soft tissue involvement is
present. Locally tumours will be controlled with 5000-
6000 rads.

129. Treatment
 CHEMOTHERAPY
For systemic treatment
Adjuvant / Neoadjuvant chemotherapy.
Multi-agent chemotherapy.
Current anti-cancer drugs are Doxorubicin,
cyclophosphamide, vincristine, actinomycin-D,
isofamide and etoposide

130. Treatment
 Surgical Management: Indications
Expendible sites
Lesions near major epiphysis
Failed radiation therapy
Large lesion with irreparable pathological
fracture

131. Surgery
 Choice made between radiation and surgery by staging the
disease, the need of the patient and the response to
chemotherapy and radiotherapy
 Debulking of the tumour limb preservation surgery has a
role
 Overall poor prognosis
 5 year survival rate is <10%
 Chemotherapy, radiotherapy with surgery- improves
survival rate 50-75% for 3-5 years

132. THANK YOU