Bone and Soft Tissue Tumours Flashcards
What is a sarcoma and describe their spread?
Malignant tumour arising from connective tissue
Spread along fascial planes
Haematogenous spread to lungs
Rarely to regional lymph nodes
Describe bone tumour prevalence
Benign skeletal tumours common
Malignant skeletal tumours rare
Bony secondaries common
Bone tumour in patient >50 likely to be metastatic
What are some bone forming tumours?
Benign
- osteoid osteoma
- osteoblastoma
Malignant
- osteosarcoma
What are some cartilage forming tumours?
Benign
- enchondroma
- osteochondroma
Malignant
- chondrosarcoma
What are some fibrous tissue tumours?
Benign
- fibroma
Malignant
- fibrosarcoma
- malignant fibres histiocytoma (MFH)
What are some vascular tissue tumours?
Benign
- haemangioma
- aneurysmal bone cyst
Malignant
- angiosarcoma
What are some adipose tissue tumours?
Benign
- lipoma
Malignant
- liposarcoma
What are some marrow tissue tumours?
Malignant
- Ewing’s sarcoma
- lymphoma
- myeloma
What are some tumour-like lesions of bone?
Benign; simple bone cyst, fibrous cortical defect
What are the commonest primary malignant bone tumours?
Osteosarcoma in younger patient
Myeloma in older patient
Describe the pain associated with bone tumours
Activity related
Progressive pain at rest and night
Benign may present with activity related pain if large enough to weaken bone
What investigations are carried out for bone pain/tumouors?
Plain X-rays; most useful for bone lesions
Calcification; synovial sarcoma
What is myositis ossificans?
A condition where bone tissue forms inside muscle or other soft tissue after an injury
What is a phlebolith?
Small, local, usually rounded calcification within a vein
Often occur with haemangioma (relatively rare benign tumour of vascular origin)
Describe the appearance of inactive bone tumours on x-ray
Inactive
- clear margins
- surrounding rim of reactive bone
- cortical expansion can occur with aggressive benign lesions
Describe the appearance of aggressive bone tumours on x-ray
- 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
Describe the use of CT in bone lesions
Assessing ossification and calcification
Integrity of cortex
best for assessing nidus in osteoid osteoma
Staging; primarily of lung mets
Why use isotope bone scans?
- staging of skeletal metastases
- multiple lesions
- frequently negative in myeloma
- benign also demonstrate increased uptake
Why use MRI in bone assessment?
- 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
What should be carried out prior to bone biopsy?
Bloods, X-Ray affected limb and chest, MRI lesion, bone scan, CT chets, abdo and pelvis
What are the cardinal features of malignant primary bone tumours?
- increasing pain
- unexplained pain
- deep-seated boring nature
- night pain
- difficulty weight-bearing
- deep swelling
What are examples of malignant primary bone tumours?
Osteosarcoma
Ewing’s sarcoma
Chondrosarcoma
What is the most common cancer to start in bone?
osteosarcoma
Clinical features of osteosarcoma
- pain (CARDINAL)
- loss of function
- swelling; generally near end of long bone
- pathological fracture
- joint effusion
- deformity
- neurovascular effects
- systemic effects of neoplasia
Describe the pain in osteosarcoma
cardinal feature
Increasing pain; impending # (esp in lower limbs)
Analgesics eventually ineffective
Not related to exercise
DEEP BORING ACHE, worse at night
What is the imaging technique of choice for osteosarcoma?
MRI; very sensitive
Good for showing
- intraosseous and extraosseous extent of tumour
- joint involvement
- skip metastases
- epiphyseal extension
Determines resection margins
Describe treatment for bone tumours
Chemo
Surgery; limb salvage possible in most cases
Radiotherapy
What are suspicious signs in a soft tissue tumour?
- 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
What are the commonest primaries which metastasise to bone?
Lung Breast Prostate Kidney Thyroid GI tract Melanoma
ALSO liver
How can you prevent pathological fracture?
Early chemo
Prophylactic internal fixation
Embolisation
Aim for early painless weight bearing + mobilisation
What is the scoring system for fracture risk assessment?
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
What are blastic lesions?
lesions which fill bone with extra cells
What are lytic lesions?
lesions which destroy bone material
