Radiological Basics of Bone Tumors

1. BONE TUMOURS
By Dr Shahid Manzur
Associate Professsor
Radiology Department
BVH

2. Bone Tumours
WHAT SHOULD YOU KNOW
•Understand the clinical algorithm
•Correlate clinical presentation with radiological features
•Understand the classification and types of bone tumours
•Comprehend the management of bone tumours
•Understand the necessity for a team-approach
•Correlate Pathological findings with clinical presentation
(Clinico-pathological correlation)

3. BONE TUMOURS
• rare but
• may result in amputation
• disfigurement and great physical challenge

4. Classification of bone tumours
Simple classification
A i. Primary
ii Secondary- more common
B i. Benign - oma
ii. Malignant - sarcoma

5. Primary Bone tumors are classified
according to the cell of origin

6. Histologic Type Benign Malignant
Hematopoietic (40%) Myeloma
Malignant lymphoma
Chondrogenic (22%) Osteochondroma Chondrosarcoma
Chondroma Dedifferentiated chondrosarcoma
Chondroblastoma Mesenchymal chondrosarcoma
Chondromyxoid fibroma
Osteogenic (19%) Osteoid osteoma Osteosarcoma
Osteoblastoma
Unknown origin (10%) Giant cell tumor Ewing tumor
Giant cell tumor
Adamantinoma
Histiocytic origin Fibrous histiocytoma Malignant fibrous histiocytoma
Fibrogenic Metaphyseal fibrous defect (fibroma) Desmoplastic fibroma
Fibrosarcoma
Notochordal Chordoma
Vascular Hemangioma Hemangioendothelioma
Hemangiopericytoma
Lipogenic Lipoma Liposarcoma
Neurogenic Neurilemmoma

7. Diagnosis of Bone Tumours
1. Age of patient
2. Location of tumour
3. Radiological appearance
4. Histological features

8. AGE(probably the most important clinical clue).
Age group Most common benign lesions Most common malignant tumors
0-20
non-ossifying fibroma
fibrous dysplasia
simple bone cyst
aneurysmal bone cyst
osteochondroma (exostosis)
osteoid osteoma
osteoblastoma
chondroblastoma
chondromyxoid fibroma
eosinophilic granuloma
Ewing's sarcoma
leukemic involvement
metastatic neuroblastoma
osteosarcoma,
Ewing's sarcoma,
21 - 40 enchondroma
giant cell tumor
chondrosarcoma
40 & above
osteoma
metastatic tumors
myeloma
leukemic involvement
chondrosarcoma
osteosarcoma (Paget's associated)
MFH
chordoma

9. SITE OF LONG BONE INVOLVEMENT
(most primary bone tumors have favored sites within long bones; this may provide a clue to
diagnosis).
Diaphyseal intramedullary lesions:
Ewing's sarcoma, lymphoma, myeloma.
Common for fibrous dysplasia and
enchondroma
Metaphyseal lesions centered in the
cortex:
Classic location for a non-ossifying
fibroma (NOF). Also, a common site for
osteoid osteoma.
Epiphyseal lesions:
Chondroblastoma (Ch) and Giant
Cell Tumor (GCT) are almost
invariably centered in the epiphysis.
Chondroblastoma is a rare tumor
seen in children and adolescents with
open growth plates. GCT is the most
common tumor of epiphyses in
skeletally mature individuals with
closed growth plates. GCT often
shows metaphyseal extension.
Metaphyseal exostosis:
Osteochondroma
Metaphyseal intramedullary lesions:
Osteosarcoma is usually centered in the
metaphysis. Chondrosarcoma and
fibrosarcoma often present as metaphyseal
lesions. Osteoblastoma, enchondroma,
fibrous dysplasia, simple bone cyst, and
aneurysmal bone cyst are common in this
location.
Diaphyseal lesions centered in
the cortex:
Osteoid osteoma

10. Radiological Features

11. Benign Tumours
Osteochondroma
Also known as an exostosis, is a cartilage –capped
out growth.
Men are affected three times more often
than women
Develop in bones of endochondral origin and arise
from the metaphysis near the growth plate of long
bones especially about the knee

12. Development over time of an osteochondroma
beginning with an outgrowth from the
epiphyseal cartilage

13. Clinically present as slow growing masses
Can be painful if they impinge on a nerve
or if stalk is fractured.
In many cases, they are detected as an
incidental finding.
Rarely they give rise to chondrosarcoma
Osteochondroma

14. Osteochondroma
of femur
The white arrows point to a mushroom-shaped, peduculated
bony excresence arising from the anteromedial aspect of the
distal femoral metaphysis, attached to the parent bone and
pointing away from the metaphyisis

15. Osteochondroma

16. Chondroma
Benign tumours of hyaline cartilage
May arise within the medullary cavity-enchondroma
May arise on the surface of bone – subperiosteal chondroma
Enchondromas are the most common
Located in the metaphyseal region of tubular bones
Most enchondromas are asymptomatic and detected
as incidental finding

17. Enchondroma of the phalanx with a
pathological fracture

18. Enchondroma with a nodule of hyaline cartilage
encased by a thin layer of reactive bone.

19. Osteoid osteoma and Osteoblastoma
Have identical histology
Osteoblastoma larger than osteoid
osteoma

20. Osteoid osteoma
< 2 cm in greatest dimension
Affects teenagers and adolescents
75 % of patients < 25 years
Affects cortex of femur or tibia
Painful lesion
Relieved by salicylate

21. Osteoid osteoma of
Femoral neck

22. Osteoid osteoma

23. 1. Compare and contrast:
Osteosarcoma
Chondrosarcoma
Giant cell tumor
Ewing's tumor
with respect to:
Histogenesis
age of group affected
location in the skeleton
histologic hallmarks
clinical behaviour
prognosis

24. Osteosarcoma (OS)
Most common primary malignant
tumor of the bone
Mesenchymal tumor
Cancerous cells produce bone matrix
75 % occur in patients younger than 20
years of age

25. Primary osteosarcoma arise in the
metaphysis of long bones of the
extremities
Secondary osteosarcomas occur in
older patients with Paget’s disease
More common in men than women
Common sites are distal end of femur
or proximal tibia
Osteosarcoma (OS)

26. Patients with Mutation of Rb gene are
predisposed to osteosarcoma
Concurrent trauma to bones and joints
In the elderly OS often arises from pre
existing bone diseases eg: Paget’s
disease of bone
Osteosarcoma (OS)

27. Clinical Presentation
Painful and progressively enlarging
masses
Spread through blood stream
The tumour breaks through the cortex
and lifts the periosteum
Often metastasizes to the lungs
Osteosarcoma (OS)

29. Osteosarcoma
on distal end of
femur
Cortex is
destroyed

30. Neoplastic osteoblasts forming osteoid

31. Chondrosarcoma
Frequency is about half of
osteosarcoma
Second most common malignant
matrix producing tumor
Mean age for chondrosarcoma is 43
years
Men are affected more than women

32. Chondrosarcomas
Commonly arise in the central
portions of the skeleton
including Pelvis, proximal femur, ribs,
sternum and shoulder girdle

33. Present as painful progressively
enlarging masses
Prognosis depends on size of tumor
Spreads to lungs and skeleton
Chondrosarcoma

35. Chondrosarcoma

36. Tumor has developed in the proximal
femur
Not destroyed the cortex
Has a bluish, glassy appearance ,
reminiscent of cartilage
Chondrosarcoma

37. Malignant neoplastic cells produce a chondroid matrix

39. The aggressiveness of chondrosarcomas can be predicted by their histologic grade. Grading system is based on three parameters: cellularity,
degree of nuclear atypia and mitotic activity.
Grade 1 (low-grade)
Very similar to enchondroma. However, the cellularity is
higher, and there is mild cellular pleomorphism. The nuclei are
small but often show open chromatin pattern and small
nucleoli. Binucleated cells are frequent. Mitoses are very rare.
Grade 1 chondrosarcomas are locally aggressive and prone to
recurrences, but usually do not metastasize.
Grade 2 (low-grade)
The cellularity is higher than in Grade 1 tumors. Characteristic
findings are moderate cellular pleomorphism, plump nuclei,
frequent bi-nucleated cells, and occasional bizarre cells.
Mitoses are rare. Foci of myxoid change may be seen. Unlike
Grade 1 tumors, about 10% to 15% of Grade 2
chondrosarcomas produce metastases.
Grade 3 (high-grade)
Characteristic findings are high cellularity,
marked cellular pleomorphism, high N/C
ratio, many bizarre cells and frequent
mitoses (more than 1 per hpf). These are
high grade tumors with significant
metastatic potential.

40. Giant cell tumour of bone (GCT)
Contains a profusion of multinucleated
osteoclast type giant cells
Relatively uncommon benign
But locally aggressive
Usually arises during 5th decade
Slight female predominance

41. Involve both epiphysis and
metaphysis
In adolescents limited to metaphysis
Common sites are distal femur and
proximal tibia
Giant cell tumour of bone (GCT)

46. Ewing sarcoma(ES)
Primary malignant small round cell
tumour
Ewing sarcoma has the youngest
average age at presentations (10-15 years)
Boys slightly more often affected than
girls

47. Pelvis is the most common site
usually arises in the diaphysis of
long bones especially femur
followed by tibia and humerus
Ewing sarcoma(ES)

48. Ewing sarcoma
of tibia from a
child

50. The following studies are required to support the diagnosis of ES and PNET:
Demonstration of t(11;22) or EWS-FLI-1 fusion transcript (present in both ES and PNET)
Immunostains(both ES and PNET are positive for CD99/O13. In addition, PNET shows positive staining with
neural markers)
EM (ES cells are undifferentiated and show prominent glycogen deposits; PNET shows neural
differentiation)

51. The pathways of spread include
Direct extension
Lymphatic or vascular dissemination
Intraspinal seeding
Ewing sarcoma(ES)

52. Secondary tumours of bone
Metastatic cancer to bone is
more common than primary
cancer of bone

53. 75% of bone metastasis originate from
Cancers of prostate
breast
kidney
lung
thyroid
Metastatic lesions are multifocal
Produce a lytic and or blastic reaction

54. Bone metastasis

55. Bone metastasis

56. Thanks