Bone and Soft Tissue Tumours Flashcards
What is a sarcoma?
A malignant tumour arising from connective tissue
How do sarcomas spread?
Spread along fascial planes is common
Haematogenous spread to lungs most common metastasis
Some subtypes also spread to regional lymph nodes
What is the most common type of soft tissue tumour?
Lipoma
What signs should make you suspicious of a malignant tumour?
- Deep tumours of any size
- Subcutaneous tumours >5cm
- Rapid growth, hard/craggy mass
When is a swelling concerning?
- Rapidly growing
- Hard, fixed, craggy mass
- Non-tender to palpation
- May be painless
- Recurred after previous excision
What features of a tumour increase the likelihood of it being metastatic?
Risk increases:
- When the tumour is deeper
- When the tumour grade is higher
- The longer the tumour has been present
When is radiotherapy effective?
Up to six months after surgery but should be started as soon as wound has healed
What are the characteristics of giant cell tumours?
Histologically benign
Can metastasise
Can be highly locally destructive
What are the different tumour-like lesions?
Simple bone cysts
Fibrous cortical defects
What are the most common primary malignant bone tumours in young and old populations?
Most common in young patients is osteosarcoma
Most common in older patients is myeloma
How does a bone tumour usually present?
Progressive pain with no abnormality on examination
Night pain will eventually develop, at which point the tumour may be palpable
What is the first line investigation in suspected bone tumour?
X-ray
What features on an x-ray indicate benign disease?
- Clear margins
- Surrounding rim of reactive bone
- Cortical expansion can occur with aggressive bone lesions
What features on x-ray indicate malignant disease?
- Less well defined zone of transition between lesion and normal bone (permeative growth)
- Cortical destruction (should make you suspicious of malignancy)
- Periosteal reactive new bone growth occurs when the lesion destroys the cortex.
- Codman’s triangle, onion-skinning or sunburst pattern
When can CT scans be helpful in bone tumours?
When assessing ossification and calcification
Can also give information on the integrity of the cortex
Helpful in staging of disease
When are isotope bone scans helpful?
- Staging for skeletal metastasis
- Multiple lesions
What are the disadvantages of isotope bone scans?
- Frequently negative in Myeloma
- Benign also demonstrate increased uptake
What are the advantages and disadvantages of MRI?
Advantages:
- Size, extent, anatomical relationships
- Accurate for limits of disease both within and outside bone
- Specific for Lipoma, haemangioma, haematoma or PVNS.
Disadvantages:
- Non-specific for benign vs. malignant
What should be done before biopsy?
- Bloods
- X-rays of affected limb and chest
- MRI of lesion
- Bone Scan
- CT Chest, abdo & pelvis
What is the diagnostic investigation in both bone and soft tissue tumours?
Needle core biopsy
What are the cardinal features of a malignant primary bone tumour?
- Increasing pain
- Unexplained pain
- Deep-seated boring nature
- Night pain
- Difficulty weight-bearing
- Deep swelling
What are the clinical features of osteosarcoma?
- pain
- loss of function
- swelling
- pathological fracture
- joint effusion
- deformity
- neurovascular effects
- systemic effects of neoplasia
What are the most common tumours that spread to the bone?
- Lung
- Breast
- Prostate
- Kidney
- Thyroid
- GI tract
- Melanoma
What parts of the skeleton are most commonly affected by secondary bone metastases?
Vertebra Proximal femur Pelvis Ribs Sternum SKull
What scoring system is used to assess risk of pathological fracture in someone with bone cancer?
Mirels scoring system
