1. ORTHOPAEDIC PATHOLOGICAL SPECIMEN AND HISTOLOGY

2. DESCRIBING GROSS SPECIMEN
A: Identify the part:
 Knee / prox. femur/ prox. tibia/ pelvis /scapula.
 Epiphyseal / Metaphyseal / Diaphyseal.
 Physeal plate visible? – Immature pt.

3. B:Describe the abnormality:
 Nature: solid / soft & friable /cystic / varigated
 Matrix: bony / cartilaginous / fibrous
 Secondary changes: central necrosis/ hemorrhage
/ cystic change
 Cortical destruction, periosteal elevation
 Intramedullary spread
 Tumor margin / capsule: well defined / illdefined
 Extension: into soft tissue / joint; invasion /
infiltration to surrounding tissue

4. C: Give provisional diagnosis.

5. Epiphyseal Diaphyseal Metaphyseal Chondroblastoma Giant cell tumor
Ewing’s sarcoma
Myeloma,
Fibro sarcoma,
Reticulum cell sarcoma
Adamantinoma
Fibrous dysplasia
Osteoid Osteoma
Metaphyseal
Most others
Ewing’s sarcoma
Myeloma
Osteoid osteoma
Ewing’s sarcoma
Myeloma
Fibrous dysplasia
Majority
Chondroblastoma
Giant cell tumor

6. Central Cortical Eccentric Enchondroma Unicameral bone cyst
Round cell tumors
Cortical
Osteoid osteoma
Eccentric
Most other tumors
Enchondroma
Unicameral bone cyst
Round cell tumors
Majority

8. GIANT CELL TUMOR  Age: 20-40.  Epiphyseal location
Incidence : 5% of all bone neoplasm
Sex : F:M = 2: 1
Bone Involved : Long tubular bones
Distal femur  Prox tibia  Distal radius –
UE Humerus  UE fibula  LE Ulna
 Epiphyseal location
(After epiphyseal closure)
 Common location: around knee (50%),
distal radius
 Xray: Geographic lytic lesion, thinned &
ballooned out cortex.
Gross pathology:
 Large red - grey - brown tumor
 Soft & friable
 Areas of cystic degeneration / necrosis &
blood filled cavities

9. Soap bubble appearance

10. HISTOPATHOLOGY:
•Uniform oval mononuclear stromal
cells : mesenchymal origin
•Appear to grow in a syncytium
•Numerous osteoclast-type giant
cells: reactive with centrally placed
uniform size nuclei (40-100)
•Necrosis, hemorrhage, hemosiderin
deposition and reactive bone
formation
•Relatively few mitotic figures in
relation to the dense cellularity of the
tumor

11. Includes the tumors which show giant cells in histology-
GIANT CELL VARIANTS
Includes the tumors which show giant cells in histology-
A. ABC
B. Brown tumor
C. Chondromyxoid fibroma, chondroblastoma
D. Desmoplastic fibroma
E. Epulis – Giant cell reparative granuloma
F. Fibrous dysplasia, non ossifying fibroma
G. Giant cell rich osteosarcoma
H. Benign fibrous histiocytoma 

12. Physiological: Megakaryocyte
Giant cell……
Physiological: Megakaryocyte
Pathological
 Langhans : fused epitheliod cells. Peripherally arranged 7-21 nuclei. TB,
histoplasmosis, sarcoidosis, other mycobacteria
 Foreign body: fused macrophages. Numerous nuclei scattered in
cytoplasm
Aschoff : Rheumatic heart disease
Reed Sternberg: Hodgkin’s lymphoma
Touton : xanthoma, xanthogranuloma, dematofibroma
Viral: Warthin Finkeldy (measles), resp syncitial virus, parainfluenza
Tumor 

13. Prominent cellular atypia
Features of malignant changes :
Size and number of giant cells decrease
Stroma shows : Heterogenicity as : Crowding, Plumping up, Increased chromatin, Increased mitotic figures.
Vascularity increases
Grading of GCT (Jaffe):
Stromal cells
Giant cells
Grade-1 or conventional GCT
Stroma less
Large number
Grade-II or Borderline GCT
Prominent cellular atypia
Decrease in number
Grade-III or fully malignant
Sarcomatous stroma
Sparse

14. Enneking’s Staging of Benign GCT
Campanacci’s Radiological Grading
Grade I – Cystic lesion
Grade II – Cortex thin but not perforated
Grade III – Tumour extended into surrounding soft tissue
Enneking’s Staging of Benign GCT
Stage I
(Latent)
10-15%
No symptom, Pathological #s may occur
Stage II
(Active)
70%
Benign, symptomatic, Pathological #s may occur
Stage III
(Aggressive)
Benign but rapidly growing, cortex perforated

15. Treatment (Grade-I and Grade-II)
Only curettage.
Curettage + bone grafting.
Curettage + bone grafting + liquid nitrogen (cryosurgery).
Extended aggressive curettage + Phenol / argon beam coagulation / bone cementing.
Grade-III – Resection + Reconstructions
Resection : En Block (Joints lost)
* Role of Radiation in GCT- spine/pelvis
( rads for 5-6 wks)

16. Giant Cell Tumour

17. Giant Cell Tumour
Giant Cell Tumour

18. OSTEOSARCOMA
 Bimodal age distribution: Primary 10-20, secondary
 75% around knee
 Bone forming tumor arising from bone
 Several subtypes –
 By location (Central or Juxtacortical)
Degree of differentiation: well to dedifferentiated
Histologic variance:
osteoblastic/chondroblastic/fibroblastic/telangictatic/small cell
 Associated with Retinoblastoma (rb gene), Li Fraumeni
syndrome (p53 gene), Rothmund Thomsen syndrome.

19. most of the medullary cavity of the metaphysis and proximal diaphysis
GROSS PATHOLOGY:
 Metaphyseal
 Tan-white solid tumor fills
most of the medullary cavity
of the metaphysis and
proximal diaphysis
 Expanding & infiltrating
through the cortex, lifts the
periosteum (Codman’s
triangle) and forms soft tissue
masses on the side of the bone
 Areas of hemorrhage and
central necrosis.

20. population- large hyperchromatic nuclei, mitotic figures
HISTOPATHOLOGY:
 Pleomorphic and anaplastic cell
population- large hyperchromatic
nuclei, mitotic figures
 Abundant fibrous/ chondroid
matrix
 Formation of pink homogenous
osteoid by neoplastic cell:
characteristic.
 The neoplastic bone has a coarse,
lacelike architecture but is also
deposited in broad sheets or as
primitive trabeculae.
 Osteoblastic, chondroblastic or
fibroblastic types
 Osteoclast-like giant cells may
be present

21. Ewing’s Sarcoma

22. CHONDROSARCOMA juxtacotical, dedifferentiated  Age: 30-60
 Primary or Secondary ( Enchondromatosis [Ollier 50%,
Maffucci 100%], diaphyseal aclasis 20%, osteochondroma 0.25%)
 Pelvis (30%), Femur (20%)
 Types: Conventional, mesenchymal, clear cell,
juxtacotical, dedifferentiated
 Most common malignant bone tumor of hand

23. GROSS PATHOLOGY: /somewhat translucent glistening tissue.
 Large bulky tumor
 Made up of lobules of gray-white
/somewhat translucent glistening tissue.
Tumor permeating throughout the
medullary cavity, growing through the
cortex, and forming a relatively well-
circumscribed soft tissue mass.
At center – necrotic/liquefied/cystic.
Gelatinous appearance secondary to
myxoid changes in matrix.
May show calcification.
The adjacent cortex is thickened or
eroded, and the tumor grows with broad
pushing fronts into the surrounding soft
tissue. 

24. cartilaginous matrix; well, moderate or poorly differentiated.
HISTOPATHOLOGY:
• Tumor cells produce
cartilaginous matrix; well,
moderate or poorly
differentiated.
• May have only minor or
focal atypia
• Intracytoplasmic hyaline
globules common in low
grade tumors

25. EWING’S SARCOMA GROSS PATHOLOGY: also pelvis, rib, scapula
James Ewing 1921
GROSS PATHOLOGY:
 Diaphyseal in long bones;
also pelvis, rib, scapula
 White tan grey mass like
brain; or red like red currant
gelly if hemorrhagic
 With necrosis & hemorrhage
 Cortical destruction
 Invasion to soft tissue,
no capsule

26. packed undifferentiated small round blue cells like
HISTOPATHOLOGY:
Homogenous & densly
packed undifferentiated
small round blue cells like
lymphocytes; regular nuclei,
infrequent mitoses, scant
clear cytoplasm. •
• Abundant glycogen: PAS +
diastase digestible
• Rare Homer- Wright
pseudorosettes (7-8 tumor
cells arranged in a circle
about a central fibrillary
space)

27. D/D : Small Round Cell Tumor
 Ewing’s: mic2 overexpression - CD99/013 . t(11;22)(EWS-FLI-1). NSE +
 PNET (Primitive neuroectodermal tumor): CD99/013. S100,
chromogranin, synaptophysin; > 20% Homer Wright rosettes
 Lymphoma (reticulum cell sarcoma, NHL): CD 45, LCA
 Small cell carcinoma: keratin, synaptophysin, chromogranin
 Mesenchymal chondrosarcoma
 Neuroblastoma: neurofilament. S100, chromogranin, synaptophysin.
 Alveolar rhabdomyosarcoma: actin, desmin, vimentin, MyoD1,
myogenin
 Leukemia

28. Osteochondroma – GROSS PATHOLOGY: thin Sessile / Pedunculated
most common benign bone tumor
AGE: during growth period
SEX: Male
SITE Attachments near metaphysis
OSTEOCHONDROMA
GROSS PATHOLOGY:
 Mushroom shaped
 Cartilage-capped bony outgrowth
 Cartilage cap usually regular and
thin
Sessile / Pedunculated
Pedunculated : attached to skeleton
by bony stalk; medullary cavity of
the osteochondroma and bone are
in continuity
Diaphyseal aclasis: multiple
heriditary exostosis
Trevor’s disease: Epiphyseal side
osteochondroma 

31. Painful osteochondroma:
 Fracture
 Bursitis
 Malignant transformation: fluffy calcification in the
cartilage cap, thickness of cartilage cap > 1 cm.
Radiology
Treatment

32. CHRONIC OSTEOMYELITIS
 Sequestrum is the necrotic
bone that is embedded in the
pus/infected granulation
tissue.
 Involucrum is the new bone
laid down by the periosteum
that surrounds the sequestra.
 Cloaca is the opening in the
involucrum through which
pus & sequestra make their
way out.

33. Types of sequestrum….. Tubular: long bone Annular: amputation stump
Ring: around pin tracts
Flake, coke, rice grain: tubercular
Button: histiocytosis
Feathery: syphilis
Match stick: sickle cell
Coloured: fungal
Black: gun shot
Bombay: exposed bone after open fracture 

34. TUBERCULAR SPONDYLITIS (POTT’S) SPINE
 Paradiscal
 Loss of height
of vertebra
 Caseating
necrotic tissue
 Bone necrosis;
sequestra
 Sclerosis

35. Acute osteomylitis is most commonly caused by
a)staphylococcus aureus
b)H. influenzae
c)Streptococcus
d)Salmonella
e) Pseudomonas

36. Earliest site of bone involvement in hematogenous osteomyelitis
a)Metaphysis
b)diaphysis
c)Epiphysis
d) Physis
e)Point of entry of nutrient artery

37. Complications of acute osteomyelitis
a)malignancy
b)fracture of the affected bone
c)sepsis
d)chronicity

38. The most common organism causing osteomyelitis in drug abusers is
a)E coli
b)pseudomonas
c)Klebsiella
d)Staph aureus

39. Giant cell tumour is located in the?
a) Epiphysis b) Metaphysis c) diaphysis d) all of the above

40. Soap bubble appearance is seen in which of the following tumours?
a) Osteosarcoma b) Chondrosarcoma c) Osteoclastoma d) Ewings sarcoma

42. A 15 year old boy is injured while playing cricket
A 15 year old boy is injured while playing cricket. X-rays of the leg rule out of a possible fracture. The radiologist reports the boy has an evidence of aggressive bone tumour with both bone destruction and soft tissue mass. The bone biopsy reveals a bone cancer with neural differentiation. Which of the following is the most likely diagnosis?
a) Chondroblastoma b) Ewing‘s sarcoma c) Neuroblastoma d) Osteosarcoma

43. Both Ewing sarcoma and peripheral neuroepithelioma belong to the Ewing family of tumors and are considered neural tumors .
Unlike neuroblastoma, these neural tumors are not derived from the sympathetic system, and catecholamine metabolites are not excreted in the urine .
In vitro, these tumors show neural differentiation and have neural features. Results with neuron-specific enolase and S-100 protein testing are positive.
electron microscopy reveals neural structures such as neurites and dense-core granules. Glycogen granules are present, and alkaline phosphatase is absent.

44. Neuroblastoma (NB) is the most common extracranial solid cancer in childhood and the most common cancer in infancy
It is a neuroendocrine tumor, arising from any neural crest element of the sympathetic nervous system (SNS).
It most frequently originates in one of the adrenal glands, but can also develop in nerve tissues in the neck, chest, abdomen, or pelvis.

46. CHONDROBLASTOMA
Although it can affect people of all ages, it most often appears in males younger than 25 years old.
Biopsy and hematoxylin and eosin (H&E) staining under high light microscopy magnification show numerous chondroblastic cells embedded in a highly mesenchymal cartilaginous matrix.
Chicken-wire calcification in a latticelike pattern surrounding the tumor cells is present in 30% of chondroblastomas.

47. Malignant tumour of mesenchymal cells characterized by formation of osteoid is description fit for ?
a) Osteosarcoma b) Chondrosarcoma c) Osteoclastoma d) Ewings sarcoma

48. Secondary osteosarcoma can be caused after?
a) Pagets disease b) fibrous dysplasia c) multiple enchondromatosis d) All the above

49. Causes of secondary osteosarcoma:
1- Radiation
2- Bone Diseases:
a) Pagets disease
b)Hereditary multiple osteochondroma
c)Enchondromatosis
d) Fibrous dysplasia
3- Inherited Cancer Syndromes:
a) Li–Fraumeni syndrome
b) Rothmund-Thomson syndrome
c) Hereditary retinoblastoma
d) Bloom syndrome
e) Werner syndrome
f) Diamond-Blackfan anemia

50. Most common site of metastasis in Osteosarcoma is ?
a) Lungs b) Heart c) Brain d) Liver

51. True statement about involucrum and sequestrum:
a) Involucrum is a piece of dead bone
b) Sequestrum is a sheath of new bone formation
c) Sequestrum is surrounded by involucrum
d) Involucrum is surrounded by sequestrum

52. Pulsatile tumor is seen in
1. Osteosarcoma 2. Osteoclastoma 3. Ewings 4. Chondrosarcoma

53. Pulsating Tumors of the Bone
*Primary tumors that may present as pulsating lesions :
1- Telengiectatic Osteogenic sarcoma
2- Angioendothelioma/Angiosarcoma of bone
3- Aneurysmal bone cyst
4- Giant cell tumor (rarely)
*Secondaries/Metastases that may present as pulsating lesions :
1- Metastasis from Renal cell carcinoma
2- Metastasis from Thyroid carcinoma

54. Ewings sarcoma is believed to arise from :
a) Aberrant cartilage rests b) Endothelial cells of bone marrow c) Mesothelial cells d) Periosteocytes

55. Which of the following malignant tumours is radio resistant?
A. Ewing’s sarcoma B. Retinoblastoma C. Osteosarcoma D. Neuroblastoma

56. Most radio resistant tumors are:
Malignant melanoma
Osteosarcoma
Pancreatic carcinoma

57. All the statements are true about exostosis, except
A. It occurs at the growing end of bone B. Growth continues after skeletal maturity C. It is covered by cartilaginous cap D. Malignant transformation may occur

58. Which of the following conditions is least likely to present as an eccentric osteolytic lesion:
A. Aneurysmal bone cyst B. Giant cell tumour C. Fibrous cortical defect D. Simple bone cyst

59. 7 year old child presents with a lesion in upper tibia
7 year old child presents with a lesion in upper tibia. X-ray shows radiolucent area with Codman’s triangle and Sunray appearance. Diagnosis is :
a) Ewing’s sarcoma b) Osteosarcoma c) Osteoid osteoma d) Chondrosarcoma

60. Sunray appearance” on x-rays is suggestive of :
1. an osteogenic sarcoma.
2. a chondrosarcoma.
3. a metastatic tumor in the bone.
4. an Ewing’s sarcoma.

61. The Codman triangle may be seen with aggressive lesions:
1- osteosarcoma
2- Ewing sarcoma
3- osteomyelitis
4- active aneurysmal bone cyst
5- giant cell tumour
6- metastasis
7- chondrosarcoma (especially juxtacortical chondrosarcoma)
8- malignant fibrous histiocytoma

63. Chondroblastomas most commonly occurs in ?
a- epiphysis b- diaphysis c- metaphysis d- medullary cavity

64. Most common benign tumour of the bone ?
a- giant cell tumour b- simple bone cyst c- osteochondroma d- enchondroma

65. Onion peel appearance on x ray is seen in?
a- osteosarcoma b- ewings sarcoma c- osteoclastoma d- osteochondroma

66. Which of the following is not a benign tumour ?
a- chondroma b- chordoma c- osteochondroma d- enchondroma

67. Most common site of osteogenic sarcoma ?
a- femur upper end b- femur lower end c- tibia upper end d- tibia lower end

68. Turn - o - plasty is used in the treatment of which of the following tumours ?
a- osteosarcoma b- osteoclastoma c- osteochondroma d- osteoblastoma e- chondrosarcoma

69. Which of the following is the least commonly affected site for chondrosarcoma?
a. Pelvis b. Proximal Femur c. Proximal Humerus d. Hands and Feet

70. A 30-year-old man has pain about his left knee that he says has been worsening "for weeks". On physical examination the left knee appears larger than the right, and there is tenderness to palpaption. A radiograph reveals a 7 cm lytic lesion involving the epiphyseal region of the distal femur with a "soap bubble" appearance. The lesion is curretted, and histologically there are numerous multinucleated cells in a stroma with plump to spindle shaped mononuclear cells. Which of the following is the most likely diagnosis? A Osteosarcoma B Chondrosarcoma C Malignant fibrous histiocytoma D Giant cell tumor E Tuberculosis

71. THANK YOU