Bone and soft tissue tumours

Question 1

Example of benign bone forming tumor (2)

Answer 1

Osteoiod osteoma

Osteoblastoma

Question 2

Example of malignant bone forming tumor (1)

Answer 2

Osteosarcoma

Question 3

Example of cartilage forming tumour
Benign (2)
Malignant (1)

Answer 3

Benign - enchondroma, osteochondroma

Malignant - chondrosarcoma

Question 4

Example of fibrous tissue tumours
Benign (1)
Malignant (2)

Answer 4

Benign - fibroma

Malignant - fibrosarcoma, malignant fibrous histiocytoma (MFH)

Question 5

Example of vascular tissue tumors
Benign (2)
Malignant (1)

Answer 5

Benign - hemangioma, aneurysmal bone cyst

Malignant - angiosarcoma

Question 6

Example Adipose tissue tumor
Benign (1)
Malignant (1)

Answer 6

Benign - lipoma

Malignant - liposarcoma

Question 7

Example of marrow tissue tumours
Malignant (3)
Which is most common primary malignant bone tumor in older patients?

Answer 7

Ewing’s sarcoma *
Lymphoma
Myeloma

Question 8

Give 2 examples of benign tumor like lesions

Answer 8

Simple bone cyst

Fibrous cortical defect

Question 9

3 clinical features of pain in bone tumour presentation

Answer 9

Activity related
Progressive pain at rest
Night pain

Question 10

Describe radiographic features of myositis ossificans (4)

Answer 10

Extraosseus bone formation
Circumferential calcification
Lucent centre
String sign

Question 11

Inactive radiographic features (3)

Answer 11

Clear margins
Surrounding rim of reactive bone
Cortical expansion (in aggressive benign lesions)

Question 12

Agressive cancer radiographic features (6)

Answer 12

Codman’s triangle
Onion skinning
Sunburst pattern
Cortical destruction
Permeative growth of cancer - less well-defined border between lesion and normal bone
Periosteal reactive - new bone growth when lesion destroys cortex

Question 13

CT x bone tumours
Function (3)
Best for…

Answer 13

1. Assessment of ossification and calcification
2. Assessment of cortical integrity
3. Assessment of nidus in osteoid osteoma
   Best for staging esp lung mets

Question 14

In an isotope bone scan what is frequently negative?

Answer 14

MM

Question 15

Which 4 conditions is MRI specific for?

Answer 15

Lipoma
Hemangioma
Hematoma
PVNS - pigmented villonodular synovitis

Question 16

What is MRI unhelpful in determining with regards to bone tumours

Answer 16

Differentiating benign vs malignant

Question 17

What is PET scan useful for with regards to bone tumours

Answer 17

Assessing response to chemotherapy

Question 18

What are the 6 components of a full blood workup needed prior to a biopsy

Answer 18

FBC
ESR, CRP
Ca, phosphate, alkaline phosphatase
LFTs - to assess mets spread
Plasma protein electrophoresis -MM
PSA - prostate mets

Question 19

Investigation of bone tumours

State 6 imaging modalities

Answer 19

X-ray - affected site and lungs
MRI
CT - chest, abdo, pelvis
Isotope bone scan
PET
Biopsy

Question 20

What are the 5 cardinal features of malignant primary bone tumours?
3 describe the quality of the pain

Answer 20

Increasing, unexplained pain
Night pain
Deep-seated, boring pain
Difficulty weight-bearing
Deep swelling

Question 21

Osteosarcoma

6 Clinical features

Answer 21

Pain, swelling and warmth
Loss of ADL functions
Pathological fracture
Joint effusion
Deformity
Systemic effects - fever, weight loss

Question 22

Osteosarcoma

what’s the first choice of investigation and why? (5 reasons why)

Answer 22

MRI *
Because it is very sensitive to osteosarcoma
Can visualize:
1. Intraosseous and extraosseous soft tissue extent of tumour
2. Joint involvement
3. Skip mets
4. Epiphyseal extension
5. Determine resection margin

Question 23

What is a skip metastasis?

Answer 23

Defined as a lateral lymph node metastasis without central lymph node involvement

Question 24

Ewing’s sarcoma
Definition
Epidemiology gender and age group

Answer 24

Malignant small round blue cell tumour

Male > female and 10-20 yo

Question 25

Ewing’s sarcoma

Sites (6)

Answer 25

Pelvis 
Femur
Humerus
Ribs
Mandible
Clavicle

Question 26

Ewing’s sarcoma
Clinical features
- Systemic symptoms
- Focal symptoms

Answer 26

Systemic symptoms 
- Intermittent fevers
- Anemia
- Leukocytosis
- Increased ESR
Focal symptoms
- Localised pain
- Swelling
- Sporadic bone pain

Question 27

Ewing’s sarcoma
Aetiology
Surgical indications (2)

Answer 27

Translocation between Ch11 and Ch22
Surgery indicated in:
- Pathological fractures
- Poorly performed biopsy

Question 28

7 sites of bone metastatic disease

PBKTL

Answer 28

Lung
Breast
Prostate
Kidney
Thyroid
GIT
Melanoma

Question 29

3 red flags of soft tissue tumours

Answer 29

1. Deep tumors of any size
2. Subcutaneous tumours > 5cm
3. Rapid growth, hard, craggy, non-tender

Question 30

Pathogenesis of metastasis

Answer 30

1. Tumor invasion of normal stromal cells
2. Increased local pressure
3. Lymphovascular invasion resulting in dislodge emboli
4. NK cells, vascular turbulence destroy tumor emboli but some survive
5. Tumour emboli adhere to capillary bed of organ and tumor angiogenesis occurs

Question 31

Most primary bone malignancies are radio-resistant except for 4

Answer 31

Multiple myeloma
Lymphoma
Ewing sarcoma
Metastatic carcinoma

Question 32

Bone TB

5 diagnostic features

Answer 32

Hx - long hx of TB
Single joint involvement
Synovial hypertrophy
Marked muscle wasting
Periarticular osteoporosis