Bone and Soft Tissue Tumours

Question 1

What is a sarcoma and describe their spread?

Answer 1

Malignant tumour arising from connective tissue

Spread along fascial planes

Haematogenous spread to lungs

Rarely to regional lymph nodes

Question 2

Describe bone tumour prevalence

Answer 2

Benign skeletal tumours common

Malignant skeletal tumours rare

Bony secondaries common

Bone tumour in patient >50 likely to be metastatic

Question 3

What are some bone forming tumours?

Answer 3

Benign

• osteoid osteoma
• osteoblastoma

Malignant
- osteosarcoma

Question 4

What are some cartilage forming tumours?

Answer 4

Benign

• enchondroma
• osteochondroma

Malignant
- chondrosarcoma

Question 5

What are some fibrous tissue tumours?

Answer 5

Benign
- fibroma

Malignant

• fibrosarcoma
• malignant fibres histiocytoma (MFH)

Question 6

What are some vascular tissue tumours?

Answer 6

Benign

• haemangioma
• aneurysmal bone cyst

Malignant
- angiosarcoma

Question 7

What are some adipose tissue tumours?

Answer 7

Benign
- lipoma

Malignant
- liposarcoma

Question 8

What are some marrow tissue tumours?

Answer 8

Malignant

• Ewing’s sarcoma
• lymphoma
• myeloma

Question 9

What are some tumour-like lesions of bone?

Answer 9

Benign; simple bone cyst, fibrous cortical defect

Question 10

What are the commonest primary malignant bone tumours?

Answer 10

Osteosarcoma in younger patient

Myeloma in older patient

Question 11

Describe the pain associated with bone tumours

Answer 11

Activity related

Progressive pain at rest and night

Benign may present with activity related pain if large enough to weaken bone

Question 12

What investigations are carried out for bone pain/tumouors?

Answer 12

Plain X-rays; most useful for bone lesions

Calcification; synovial sarcoma

Question 13

What is myositis ossificans?

Answer 13

A condition where bone tissue forms inside muscle or other soft tissue after an injury

Question 14

What is a phlebolith?

Answer 14

Small, local, usually rounded calcification within a vein

Often occur with haemangioma (relatively rare benign tumour of vascular origin)

Question 15

Describe the appearance of inactive bone tumours on x-ray

Answer 15

Inactive

• clear margins
• surrounding rim of reactive bone
• cortical expansion can occur with aggressive benign lesions

Question 16

Describe the appearance of aggressive bone tumours on x-ray

Answer 16

• less well defined zone of transition between lesion and normal bone (permeative growth)
• cortical destruction = malignancy
• periosteal reactive new bone growth occurs when lesion destroys cortex

Question 17

Describe the use of CT in bone lesions

Answer 17

Assessing ossification and calcification

Integrity of cortex

best for assessing nidus in osteoid osteoma

Staging; primarily of lung mets

Question 18

Why use isotope bone scans?

Answer 18

• staging of skeletal metastases
• multiple lesions
• frequently negative in myeloma
• benign also demonstrate increased uptake

Question 19

Why use MRI in bone assessment?

Answer 19

• size, extent, anatomical relationships
• accurate for limits of disease both within and outside bone
• specific for lipoma, haemangioma, haematoma
• non specific for benign v malignant

Question 20

What should be carried out prior to bone biopsy?

Answer 20

Bloods, X-Ray affected limb and chest, MRI lesion, bone scan, CT chets, abdo and pelvis

Question 21

What are the cardinal features of malignant primary bone tumours?

Answer 21

• increasing pain
• unexplained pain
• deep-seated boring nature
• night pain
• difficulty weight-bearing
• deep swelling

Question 22

What are examples of malignant primary bone tumours?

Answer 22

Osteosarcoma
Ewing’s sarcoma
Chondrosarcoma

Question 23

What is the most common cancer to start in bone?

Answer 23

osteosarcoma

Question 24

Clinical features of osteosarcoma

Answer 24

• pain (CARDINAL)
• loss of function
• swelling; generally near end of long bone
• pathological fracture
• joint effusion
• deformity
• neurovascular effects
• systemic effects of neoplasia

Question 25

Describe the pain in osteosarcoma

Answer 25

cardinal feature Increasing pain; impending # (esp in lower limbs) Analgesics eventually ineffective Not related to exercise DEEP BORING ACHE, worse at night

Question 26

What is the imaging technique of choice for osteosarcoma?

Answer 26

MRI; very sensitive Good for showing - intraosseous and extraosseous extent of tumour - joint involvement - skip metastases - epiphyseal extension Determines resection margins

Question 27

Describe treatment for bone tumours

Answer 27

Chemo Surgery; limb salvage possible in most cases Radiotherapy

Question 28

What are suspicious signs in a soft tissue tumour?

Answer 28

- deep tumours of any size - subcut tumour >5cm - rapid growth, hard, craggy, non-tender - rapidly growing swelling all patients with suspected malignancy should be referred to specialist tumour centre

Question 29

What are the commonest primaries which metastasise to bone?

Answer 29

``` Lung Breast Prostate Kidney Thyroid GI tract Melanoma ``` ALSO liver

Question 30

How can you prevent pathological fracture?

Answer 30

Early chemo Prophylactic internal fixation Embolisation Aim for early painless weight bearing + mobilisation

Question 31

What is the scoring system for fracture risk assessment?

Answer 31

Mirel's scoring system Score 1; - upper limb - mild pain - blastic lesion - <1/3 size Score 2; - lower limb - moderate pain - mixed tumour - 1/3 to 2/3 size Score 3 - peritrochanter location - functional pain - lytic lesion - >2/3 size

Question 32

What are blastic lesions?

Answer 32

lesions which fill bone with extra cells

Question 33

What are lytic lesions?

Answer 33

lesions which destroy bone material