Bone and Soft Tissue Tumours Flashcards
What is a sarcoma?
Malignant tumour that arises from connective tissue
How do sarcomas spread?
- Spread along fascial planes
- Haematogenous spread to lungs
- Rarely to regional lymph nodes (rhabdomyosarcomas, epithelioid sarcomas & synovial sarcomas)
What is a bone tumour in a patient over 50 likely to be?
Metastatic
Bone tumours: Malignant vs benign
- Benign tumours are common
- Malignant tumours are RARE
- Bony secondaries are common
Name some benign bone-forming tumours.
- Ostoid osteoma
- Osteoblastoma
Name a malignant bone forming tumour.
Osteosarcoma
Name some benign cartilage forming tumours.
- Enchondroma
- Osteochondroma
Name a malignant cartilage forming tumour.
Chondrosarcoma
Name a benign fibrous tissue tumour.
Fibroma
Name some malignant fibrous tissue tumours.
- Fibrosarcoma
- Malignant fibrous histiocytoma (MFH)
Name some benign vascular tissue tumours.
- Haemangioma
- Aneurysmal bone cyst
Name a malignant vascular tissue tumour.
Angiosarcoma
Name a benign adipose tissue tumour.
Lipoma
Name a malignant adipose tissue tumour.
Liposarcoma
Name some malignant marrow tissue tumours.
- Ewing’s sarcoma
- Lymphoma
- Myeloma
What are the features of giant cell tumours (GCT)?
Benign, locally destructive and can rarely metastasise
Name some benign tumour like lesions.
- Simple bone cyst
- Fibrous cortical defect
What is the incidence of primary bone tumours in the UK?
Per million population per year
- Osteosarcoma: 3
- Chondrosarcoma: 2
- Ewing’s sarcoma: 1.5
- Malignant fibrous histiocytoma: <1
What is the commonest primary malignant bone tumour in young patients?
Osteosarcoma
What is the commonest primary malignant bone tumour in older people?
Myeloma
What history do bone tumours present with?
- PAIN
- Mass
- Abnormal x-ray (incidental)
Describe the pain associated with bone tumours.
- Activity related
- Progressive pain at rest and night
How might benign tumours present?
-Activity related pain if large enough to weaken the bone (can occur in osteoid osteomas)
What should be noted on examination when someone presents with a bony mass?
- General health
- Measurements of mass
- Location
- Shape
- Consistency
- Mobility
- Tenderness
- Local temperature
- Neuro-vascular deficits
What investigations should be carried out?
- Plain x-rays (most useful for bone
- CT
- Isotope bone scan
- MRI (study of choice)
- Angiography
- PET
- Biopsy
How do inactive tumours appear on x-ray?
- Clear margins
- Surrounding rim of reactive bone
- Cortical expansion can occur with aggressive benign lesions
How do aggressive tumours appear 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 the lesion destroys the cortex. (Codman’s triangle, onion-skinning or sunburst pattern)
Give examples of what may be seen on x-ray?
- Calcification in synovial sarcoma
- Myositis ossificans
- Phleboliths in haemangioma
What is the role of CT in diagnosing bone and soft tissue tumours?
- Assessing ossification and calcification
- Integrity of cortex
- Best for assessing nidus in osteoid osteoma
- Staging - primarily of lungs
What role do isotope bone scans play in diagnosing bone and soft tissue tumours?
- Staging for skeletal metastasis
- Multiple lesions - osteochondroma, enchondroma, fibrous dysplasia & histiocytosis
- Frequently negative in Myeloma
- Benign also demonstrate increased uptake
What is the role of MRI in diagnosing bone and soft tissue tumours?
- Size, extent, anatomical relationships
- Accurate for limits of disease both within and outside bone
- Specific for Lipoma, haemangioma, haematoma or PVNS.
- Non-specific for benign vs. malignant
What may PET scans be useful in?
Investigating response to chemo
What is angiography used for?
- Pseudo aneurysms, AV malformations
- Embolisation of vascular tumours: renal, ABC
What work up must be carried out before biopsy?
Complete work up
- Bloods
- X-rays of affected limb and chest
- MRI of lesion
- Bone scan
- CT chest, abdomen and pelvis
How can we differentiate between benign and malignant?
- History
- Clinical findings
- Radiological features
- Biopsy – needle core vs. Open
- Treatment
- Reconstruction
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 the clinical features of bone tumours?
- Pain
- Loss of function
- Swelling
- Pathological fracture
- Joint effusion
- Deformity
- Neurovascular effects
- Systemic effects of neoplasia
What are the features of the pain associated with bone tumours?
- Cardinal feature
- Increasing pain with impending fracture (especially lower limb)
- Analgesics eventually ineffective
- Not related to exercise
- DEEP BORING ACHE WORSE AT NIGHT
What loss of function may occur with bone tumours?
- Limp
- Reduced joint movement
- Stiff back (especially child)
What are the features of swelling associated with bone tumours?
- Generally diffuse in malignancy
- Generally near end of long bone
- Once reaching noticeable size, enlargement may be rapid
- Warmth over swelling and venous congestion=active
- Pressure effects
What is a pathological fracture?
A fracture that occurs with minimal trauma, history of pain prior to fracture and underlying disease
What is the investigation of choice in bone tumours?
MRI scan
What are MRI scans very good at showing in bone tumours?
- Intraosseous (intramedullary) extent of tumour
- Extraosseous soft tissue extent of tumour
- Joint involvement
- Skip metastases
- Epiphyseal extension
What are the treatments for bone tumours?
Goal is to make free of disease
- Chemotherapy
- Surgery
- Radiotherapy
When is surgery used in the treatment of bone tumours?
- Limb salvage in most cases
- Consider involvement of neurovascular structures
- Pathological fractures
- Poorly performed biopsy
Where should patients with a soft tissue tumour that is suspected to be malignant be referred?
Specialist tumour centre
What are suspicious signs in soft tissue tumours?
- Deep (i.e. deep to deep fascia) tumours of any size
- Subcutaneous tumours > 5 cm
- Rapid growth, hard, craggy, non-tender
Beware of swelling which is…
- Rapidly growing
- Hard, fixed, craggy surface, indistinct margins
- Non-tender to palpation, but assoc. with deep ache, esp. worse at night
- BEWARE – may be painless
- Recurred after previous excision
Suspicious of malignant tumour (primary or secondary) until proven otherwise
How does the incidence of metastatic bone tumours compare to primary bone tumours?
Secondary bone tumour 25x more common than primary
How common are bone secondaries?
Bone most common site for secondary after lung and liver
Name a cancer which commonly spreads to the bone.
Breast
How do sites of bony metastasis vary?
Order of frequency
- Vertebrae
- Proximal femur
- Pelvis
- Ribs
- Sternum
- Skull
What are the 7 commonest primary cancers which metastasise to bone?
- Lung
- Breast
- Prostate
- Kidney
- Thyroid
- GI tract
- Melanoma
What does survival after pathological fracture depend on?
Type of tumours
- Bronchial cancer <1 year
- Breast with soft tissue mets 12-24 months
In general, approx. 50% of patients with pathological fractures will survive >6 m, & 30% 1 y
How are pathological fractures prevented?
-Early chemotherapy/DXT
-Prophylactic internal fixation
-+/- Bone cement
-Embolisation
-Only one long bone at a time
Aim for early painless weight bearing and mobilisation
-Fracture of non-WB skeleton can be treated conservatively but frequent refracture
What system is used for fracture risk in metastatic bone disease?
Mirel’s scoring system
What are the components of Mirel scoring system?
Site
- UL
- LL
- Peritrichanter
Pain
- Mild
- Moderate
- Severe
Lesion
- Blastic
- Mixed
- Lytic
Size
- <1/3
- 1/3-2/3
- > 2/3
What are the key points for metastatic bone disease according to the BOA working party?
- Prognosis is improving
- Never assume a lytic lesion is metastasis
- Metastatic pathological fractures rarely unite, even if stabilised
- Prophylactic fixation of long bone mets is generally easier for the surgeon and less traumatic for the patient
- Mirel scoring system
- High failure rate of fixation of path# around hip/proximal femur. Lower failure rate for cemented hip prosthesis
- Use traction and splintage while performing investigations and conducting MDT before fixing path#
- Decompression and stabilisation of spinal mets
- Constructs should be weight bearing and last the patient’s lifetime
- Solitary renal mets should be excised
- Each trauma group requires a lead clinician for MBD
- Use of MDT
What is the commonest soft tissue tumour?
Lipoma
How does the incidence of lipoma compare to sarcoma?
- <5cm 150:1
- > 5cm 20:1
- > 10cm 6:1
- Deep seated 4:1
What are the clinical features of soft tissue tumours?
- Painless
- Mass deep to deep fascia
- Any mass >5cm
- Any fixed, hard or indurated mass
- Any recurrent mass
What imaging study should be carried out for soft tissue tumours?
MRI
